Based on meteorological and yield data of summer maize growth period in Huaibei City, Anhui Province from 1982 to 2021, the characteristics of climate change during the growth period of summer maize in the region and its impact on yield were analyzed using trend analysis, moving average method, and Pearson correlation analysis method. The results showed that (1) from 1982 to 2021, the study area had sufficient precipitation, heat, and sunshine resources during the growth period of summer maize, which met the growth and development of summer maize. (2) From 1982 to 2021, the changes in summer maize yield and meteorological yield in the study area showed a consistent downward trend, with significant interannual variations in yield and scattered distribution of meteorological yield. By analyzing the relative meteorological yield, it could be concluded that the typical years of summer maize yield deficit in this region were 1987, 1994, 2003, 2007 and 2014, mainly affected by meteorological disasters such as drought and waterlogging (including continuous rainy weather). (3) The diurnal temperature range and precipitation were the key meteorological factors affecting the yield of summer maize in study area, among which the diurnal temperature range during the milk ripening maturity period is significantly positively correlated with yield (P<0.01); The precipitation during the tasseling milk ripening period is significantly negatively correlated with yield (P<0.05); The average temperature, effective accumulated temperature≥10 ℃, and sunshine hours have no significant impact on yield. This article provides a reference for regulating the microclimate in the field and improving maize yield.

To investigate the effects of mixed substrates of cow dung-maize straw compost and vegetable garden soil on the growth and quality of potted garlic seedings, an experiment was conducted from August to November 2024 using compost (1∶1 volume ratio of cow dung and maize straw) and garden soil as materials, with pure vegetable garden soil as the control (CK). The compost and garden soil were mixed at volume ratios to form 6 treatments: T₁–T₆ at 1∶9, 2∶8, 3∶7, 4∶6, 5∶5 and 6∶4, respectively. The physicochemical properties of the substrates were measured, and samples were taken at 30, 60 and 90 days after sowing to determine growth indicators such as plant height and quality indicators such as soluble protein content in the leaves and pseudostems. The results showed that compared with CK, as the proportion of compost increased, the bulk density and pH of the substrate gradually decreased, while the total porosity, water-holding porosity and aeration porosity gradually increased. The height, pseudostem diameter and pseudostem length of garlic seedlings in each treatment were significantly increased, and the root activity and chlorophyll content showed an overall trend of first increasing and then decreasing. The contents of soluble protein, vitamin C and allicin were all relatively high. The growth and quality indicators of treated with T₃ were superior. At 30, 60 and 90 days, the plant height, pseudostem diameter, pseudostem length, leaf weight, pseudostem weight, total plant weight, root vitality, and chlorophyll content increased by 8.5%-22.4%, 51.0%-100.0%, 25.5%-58.4%, 13.0%-38.8%, 16.0% -29.0%, 15.6%-28.1%, 18.5%-36.4%, and 20.1%-31.2% respectively compared to the CK. The contents of soluble protein, vitamin C, and allicin in the leaves increased by 8.4% - 27.2%, 14.9% - 22.7%, and 37.0%-57.1% respectively compared to the the CK. The contents of soluble protein, vitamin C, and allicin in the pseudostem increased by 18.4%-24.0%, 15.7%-30.4%, and 18.9%-30.9% respectively compared to the CK. In conclusion, the mixed substrate of cow dung-maize straw compost and garden soil promotes the growth of garlic sprouts and the accumulation of photosynthetic products, improving their overall quality. The T₃ treatment (3∶7 volume ratio of cow dung-maize straw compost to vegetable garden soil) demonstrated the best results and can be applied in garlic seedlings cultivation.

【Objective】 Exploring the effects of conservation tillage and nitrogen application on soil carbon and nitrogen mineralization characteristics, as well as their impact mechanisms on maize photosynthetic characteristics and yield, in order to provide a basis for improving soil fertility and promoting maize production in arid areas of Northwest China.【Method】 This study conducted a two-year (2019-2020) maize field location experiment, with traditional tillage (CT) as the control, and set up three protective tillage measures (no tillage: NT; no tillage in wheat season and rotary tillage in maize season: OT; ridge cultivation with no tillage: RNT) and two nitrogen application levels (N0: 0; N2: 170 kg N·hm^-2), for a total of 6 treatments. The effects of conservation tillage and nitrogen application on soil nutrient content, carbon and nitrogen mineralization characteristics, maize photosynthetic physiological characteristics, and yield were investigated systematically. 【Result】 Conservation tillage and nitrogen application significantly increased soil nutrient content (P<0.05). Under N2 level, compared with CT treatment, NT, OT, and RNT treatments increased soil organic carbon (SOC), microbial biomass carbon (MBC), total nitrogen (TN), and microbial biomass nitrogen (MBN) content by 8.6%-24.7%, 18.9%-27.0%, 8.9%-20.2%, and 0.3%-24.9%, respectively. The application of nitrogen significantly increased the accumulation of soil carbon mineralization (C_min), nitrogen mineralization accumulation (N_min), and their mineralization rates. Conservation tillage further improved the soil carbon and nitrogen mineralization characteristics. C_min and N_min reached their maximum values under RNTN2 and OTN2 treatments, respectively, which increased by 4.0%-30.2% and 8.0%-52.4% compared with other treatments. Conservation tillage and nitrogen application significantly increased the net photosynthetic rate (Pn), transpiration rate (Tr), and stomatal conductance (Gs) of maize leaves (P<0.05). The Pn, Tr, and Gs of maize reached their maximum values in the OTN2 treatment for two years. The yield of maize in two years showed the order of OTN2>RNTN2>NTN2>CTN2>NTN0>CTN0, with the highest yields of 10.52 and 10.91 t·hm^-2, respectively, which increased by an average of 24.5% and 27.5% compared with other treatments. Based on structural equation modeling analysis, it was found that conservation tillage mainly increased soil nutrient content, promoted soil organic carbon and nitrogen mineralization, enhanced soil available nitrogen supply capacity, and thus promoted the enhancement of maize photosynthetic capacity, achieving maize yield increase. 【Conclusion】 In the arid northwest region, conservation tillage and nitrogen application were of great significance in promoting soil carbon and nitrogen mineralization, increasing maize yield, and maintaining soil productivity. It was recommended that no tillage in wheat season and rotary tillage in maize season combined with nitrogen application was the optimal management measures for increasing maize yield and efficiency.

To screen maize inbred lines with high combining ability for single plant grain weight and nitrogen fertilizer agronomic efficiency, using 15 inbred lines as materials, 56 hybrid combinations were constructed according to the NCⅡ mating design. Under low nitrogen stress, the general combining ability of inbred lines for single plant grain weight and nitrogen fertilizer agronomic efficiency were estimated, as well as the specific combining ability of hybrid combinations. The results indicated that the inbred lines with positive general combining ability effects for single plant grain weight were WZ14212, WZ1718-2, 1734A10, Z7A-21, 1734B325, 1735A2 and WZ853, with effect values of 3.97, 2.86, 2.55, 2.13, 1.14, 0.75 and 0.74, respectively. There were 8 hybrid combinations with the special combining ability effect values greater than 7, ranging from 7.46 to 10.64. The inbred lines showed positive general combining ability for nitrogen fertilizer agronomic efficiency were WZ14212, 1734A10, WZ853, 195-73, WZ1718-2 and 1735A2, with effect values of 9.96, 5.06, 4.63, 2.45, 1.78 and 1.55, respectively. There were 11 hybrid combinations with the special combining ability effect values greater than 10, ranging from 10.95 to 24.86. Correlation analysis showed that under low nitrogen stress, there was a significant positive correlation between the single plant grain weight of hybrid combinations and the general combining ability of the single plant grain weight with male parent inbred line, r were 0.2921^*; there were highly significant and significant positive correlations between nitrogen fertilizer agronomic efficiency of hybrid combinations and the general combining ability of nitrogen fertilizer agronomic efficiency with its diploid inbred lines, r were 0.3848^** and 0.3289^*, respectively; and there were highly significant positive correlations between both the single plant grain weight and agronomic efficiency of nitrogen fertilizer in hybrid combinations with their total combining ability effects, r were 0.9669^** and 0.9455^**, respectively. The results suggested that WZ14212, WZ1718-2, Z7A-21, 1734A10, 1734B325, 1735A2 and WZ853 could be inbred lines developing hybrid combinations with high single plant grain weight and nitrogen fertilizer agronomic efficiency in maize breeding programs.

In order to assess the suitability of MaizeSM crop model in Tumd Left Banner, a global sensitivity analysis method was employed to identify sensitive parameters of the model. Subsequently, localized model parameters were calibrated using maize variety data from experimental fields, meteorological observations, soil physical and chemical data, and field management records spanning 2010 to 2022. This calibration enabled accurate simulation and prediction of local maize growth processes and characteristics across different stages. Accuracy of simulation results was verified using actual yield and growth period duration indicators. The results showed that findings revealed nine sensitive parameters within the model, with k₁ (emerging-joining stage basic development coefficient) being identified as most sensitive while TR₁ (stem sheath storage transport efficiency parameter before flowering) exhibited minimal sensitivity. Strong correlations between simulated values for each growth period and actual values were observed, with normalized root-mean-square error (NRMSE) below 30% and root-mean-square error (RMSE) falling within an acceptable range. The crop model can simulate the local maize growth well. The crop model demonstrates good simulation performance for local maize growth. The localized maize growth simulation model, MaizeSM, with improved parameters, has enhanced the refined yield prediction based on station-scale agricultural meteorological services. This further strengthens the application capabilities of agricultural models in climate change impact assessment, operational services, and agricultural production in the Tumd Left Banner region. These advancements assist agricultural managers in formulating optimal planting strategies to achieve maximum production efficiency.

To clarify the interaction effects of planting density and N-fertilization rate of summer maize, the maize varieties ‘DH605’ and ‘MY73’ were used as experimental materials, 2 densities (67500 plants/hm², 82500 plants/hm² ) and 2 N-fertilization rate (210 kg/hm², 300 kg/hm²) were set to analyze the effects of density and N-fertilization on summer maize yield. The results showed that as the density increased, the effective number of ears increased, and yield increased by 18.0%, while the number of grains per spike and the number of grains per row decreased significantly; increasing N-fertilization rate could reduce the adverse effects of densification on maize plant yield and ear traits. The yield increased by 6.0%, the kernels per ear increased by 2.6%, and the leaf area per plant increased by 6.4%. Density and N-fertilization rate mainly affected the kernels per ear. ‘MY73’ had higher yield, better ear characteristics and leaf area under high-density and high N-fertilization rate conditions. It was found that the adverse effects of maize plant and population competition after increasing planting density could be regulated by appropriate increase of nitrogen fertilizer. Therefore, when the planting density of the two varieties increased to 82500 plants/hm², the N-fertilization rate of 300 kg/hm² was more likely to achieve high yield. The study is expected to provide some technical support for the synergistic improvement of summer maize quality and yield in western Henan.

In this paper, the evolution characteristics (spatiotemporal distribution, persistence, intensity, etc.) of summer high temperature days and heat waves in the middle of Hexi Corridor were studied, and the effects on the growth and yield components of maize during the critical period were analyzed, providing theoretical foundations for the development of early warning of high temperature events, risk prediction, maize flowering and yield forecasting services in the region. Based on daily maximum air temperature data from June to August at meteorological stations in the middle of Hexi Corridor from 1961 to 2023, linear trend, Mann-Kendall test and other methods were used to reveal the frequency, process, intensity characteristics and evolution of high temperature weather, and to analyze the effects on the growth traits and yield components such as 100-seed weight of maize, the local dominant crop. The results indicated that high temperature weather in the middle of Hexi Corridor mainly occurred in the desert oasis from late July to early August. An abrupt change of high temperature weather took place in the late 1990s. About the number of (hazardous) high temperature days and heat waves, big interannual changes, massive occurrences in a short time and an upward trend were discovered. There was a significant negative correlation between the number of high temperature days and the spike period. The intervals between tasseling and silking stages in years with more high temperature days were equal or shorter than the climatological normal. In years with more high temperature days in the jointing-booting stage, the tasseling-silking stages were simultaneous or delayed compared to climatological normals. The number of high temperature days during and after the flowering stage was significantly negatively correlated with 100-seed weight (R=-0.8495). For every additional day, the 100-seed weight decreased by 1.345 grams. Finally, it is proposed to establish an intelligent agricultural monitoring network to predict disasters, carry out experiments on high temperature meteorological applicable technologies and screen high temperature resistant varieties to cope with high temperature risk, so as to ensure high quality and high yield of maize.

To clarify the comparative advantage characteristics of corn planting regions in Yunnan Province, based on the corn planting region and yield data of 16 prefectures and cities in Yunnan Province from 2000 to 2020, production scale index, production concentration index, scale comparative advantage index, efficiency comparative advantage index, and comprehensive comparative advantage index were used to calculate and analyze. The results showed that: (1) the corn planting regions in Yunnan Province were concentrated in the northeast and south, especially in Qujing, Zhaotong, and Wenshan. (2) Qujing, Zhaotong, Wenshan, Pu'er, and Lincang had contributed the most to the total corn planting area in the province, which concentrated more than half of the total maize planting area in the province. (3) Qujing, Zhaotong, Wenshan, Dali, and Honghe had contributed the most to the province's corn yield, accounting for more than half of the total corn yield in the province. (4) The comparative advantage of corn production scale in Yunnan Province was generally on the rise, while the comparative advantage of corn production efficiency and comprehensive comparative advantage were generally stable. The comprehensive advantageous production regions had been formed in the northeast regions such as Zhaotong and Qujing, the southeast regions such as Wenshan, and the southwest regions such as Lincang, and the northwest regions such as Nujiang and Diqing. The scale comparative advantage accelerated the continuous enhancement of the polarization effect of comprehensive comparative advantage. In order to accelerate the high-quality development of the corn industry in Yunnan Province, it is necessary to continuously ensure policy support for advantageous corn planting regions, gradually tap into the production potential of corn planting comparative advantages, and appropriately reduce the proportion of corn in non advantageous corn planting regions.

To investigate the characteristics of the dynamic changes of root morphology of silage maize in different periods under the conditions of nitrogen and phosphorus rationing in the wind and sand area of Yulin, silage maize (Zea mays) ‘Dajingjiu 23’ was used as the research object. A two-factor test was set up for nitrogen and phosphorus fertilizers, with the nitrogen application of no nitrogen (N0, 0 kg/hm²), low nitrogen (N90, 90 kg/hm²), medium nitrogen (N180, 180 kg/hm²), medium-high nitrogen (N270, 270 kg/hm²) and high nitrogen (N360, 360 kg/hm²); and phosphorus was applied as no phosphorus (P0, 0 kg/hm²), low phosphorus (P90, 90 kg/hm²) and high phosphorus (P180, 180 kg/hm²). The biomass and root morphology of silage maize were measured at the trumpet stage, silking stage and harvesting stage. The results showed that the nitrogen-phosphorus rationing significantly promoted the longitudinal development of the root system at the trumpet stage, and the fresh weight, root length and surface area of the root system in the 10-20 cm soil layer increased by 73.9%-169.5%, 52.0%-136.4% and 75.1%-124.4%, respectively. Nitrogen-phosphorus rationing had a significant effect on the expansion of the shallow root system during the silking stage, with the fresh weight, dry weight and volume of the root system in the 0-10 cm soil layer increasing by 5.5%-69.3%, 3.9%-62.1% and 3.0%-91.4%, respectively. Nitrogen-phosphorus rationing effectively delayed root senescence at harvest, with increases of 28.5%-190.3% in fresh weight in the 10-20 cm soil layer, and increases of 50.0%-202.3% and 40.2%-158.8% in dry weight and volume in the 20-30 cm soil layer, respectively. The root indexes of each fertility stage showed that the fresh weight, dry weight, root length, surface area and volume of roots in the 0-20 cm soil layer were significantly better than those in the 20-40 cm layer. Through the comprehensive evaluation of the affiliation function, the optimal performance of the N180P180 program was observed, with the above-ground fresh and dry weights increasing by 24.7% and 44.7%, respectively, and the root development indexes showing a sustained gain. The fresh weights increased by 54.5%-91.1%, the dry weight increased by 28.5%-70.6%, the root length increased by 23.8%-70.8%, the total area increased by 52.1%-79.3%, and the total volume increased by 32.6%-98.9%, and a significant increase in the efficiency of nutrient uptake by the plant. In conclusion, the N180P180 dosage was favorable to promote the synergistic growth of maize above-ground and below-ground.

The study aims to investigate the effects of fertilization on yield, quality, fertilizer use efficiency in maize (variety ‘Fuhua 22’) and rapeseed (variety ‘Yunyouza 15’) and discharge amount of fertilizer pollution, providing scientific guidance for optimizing fertilizer management of major crops in the upper reaches of the Chishui River. A field experiment with five treatments was implemented, including control (CK), phosphorus-potassium (PK), nitrogen-potassium (NK), nitrogen-phosphorus (NP), and nitrogen-phosphorus-potassium (NPK), to assess their effects on crop yield, quality at maturity, fertilizer use efficiency, and discharge amount of fertilizer pollution. The results showed that the NPK treatment significantly increased rapeseed yield by 81.73% compared to CK, whereas the yield increases under nutrient-deficient treatments (PK, NK, NP) ranged only from 35.42% to 52.86%. In terms of quality, fertilization significantly increased the contents of fat, protein, oleic acid and erucic acid, but had no significant effects on palmitic acid, stearic acid, linoleic acid or linolenic acid contents. Similarly, maize yield under NPK treatment increased by 90.00% compared to CK, whereas the yield increases under nutrient-deficient treatments (PK, NK, NP) ranged only from 42.74% to 79.24%. In terms of quality, the NPK treatment exhibited the highest maize starch and protein contents, which increased by 4.94% and 60.47%, whereas nutrient-deficient treatments demonstrated comparatively smaller increments. In addition, the study also found that the nitrogen, phosphorus, and potassium utilization efficiencies of maize and rapeseed reached their highest levels under NPK fertilization conditions. Under NPK fertilization conditions, nitrogen and phosphorus pollution from maize and rapeseed fields were minimized, being significantly lower than those under nutrient-deficient treatments. In conclusion, balanced fertilization not only significantly enhanced crop yield and quality along with the fertilizer use efficiency, but also effectively mitigated agricultural non-point source pollution.

Using humic acid water-soluble fertilizer produced by Zhongcheng Guolian (Henan) Biotechnology Co., Ltd. as the test material, this study investigated the impact of foliar application of humic acid water-soluble fertilizers on the yield and yield factors of wheat and summer maize under different soil texture types in Shangqiu City. The paired test design was used, and the effects on economic benefits were also analyzed. The results showed that with foliar spraying of humic acid water-soluble fertilizer, the number of grains per ear, 1000-grain weight and both yield and economic benefits significantly increased. Statistical analysis revealed a highly significant increase in yield for both wheat and summer maize. The increase in yield and economic benefit varied across different soil texture types. For wheat, the highest yield increase and lowest yield increase rate occurred on silty soil. The highest increase rate and smallest yield increase were found on sandy soil. The order of net increase in economic benefit was silty soil> loamy soil> sandy soil. For summer maize, the yield increase ranking was silty soil> sandy soil> loamy soil, while the orders of increase rate and net increase in economic benefit were loamy soil> silty soil> sandy soil.

To explore the impacts of applying nitrogen, phosphorus and potassium fertilizers, as well as micro elements, on the yield and quality of black corn, black corn ‘SK9179’, ‘SK9176’ and ‘SK9115’, which were self-selected breeding, were taken as test materials, and a multi-point comparison and repeated test design was carried out. The effects of formula fertilizers with nitrogen, phosphorus and potassium ratios of 2:1:2 and 2:1:1， and the supplementary application of the micro elements zinc and boron on the yield and quality of black corn were investigated. Both the 2:1:2 and 2:1:1 NPK ratios were found to enhance the yield and quality of black corn, with the ratio 2:1:2 demonstrating the most favorable results. Applying 0.75% zinc sulfate at the ratio of 2:1:2, the yield of ‘SK9179’ black corn reached the highest 18223.5 kg/hm², and the anthocyanin contents in the corn kernels and cobs were as high as 0.40% and 1.68%, respectively. However, the combined application of zinc sulfate and borax was observed to decrease the yield and quality of black corn. An excessive amount of nitrogen in the soil had a negative impact on the accumulation of anthocyanins and the formation of yield in black corn. Therefore, it was recommended that during the cultivation of black corn, the application amount of nitrogen fertilizer should be reduced, while the application amounts of phosphorus and potassium fertilizers should be increased.

The experiment explored the effects of different row ratios of corn and peanut strip compound planting on the growth of two crops, aiming to find a suitable row ratio and provide theoretical support for field production. Taking‘Yamei 1’ corn variety and ‘Heyou 16’peanut variety as materials, the corn and peanut strip compound planting experiment was set up with six different intercropping row ratios of 2:4, 2:6, 2:8, 4:4, 4:6 and 4:8 and corn monoculture and peanut monoculture (recorded as: C₂P₄, C₂P₆, C₂P₈, C₄P₄, C₄P₆, C₄P₈, CK₁, CK₂). A random block design was adopted, each replicated three times, totaling 24 experimental cells. The SPAD value of leaves, plant agronomic traits, yield and other related indicators were measured during crop growth period. Compared with the monoculture, the yield per unit area of the two crops decreased to varying degrees, and the SPAD values of the leaves of the corn and peanut seedlings were not significantly different. Under the premise of the fixed number of corn planting rows, with the increase of the number of peanut planting rows in the middle and late stages of the growth period, the SPAD value of corn leaves, the actual yield and the SPAD value of peanut leaves, hundred fruit weight, hundred kernel weight, kernel rate and actual yield all showed an upward trend. The SPAD value, ear height, grain number per ear and seed rate of the 2-row corn planting belt were higher than those of the 4-row corn planting belt. The plant height, the first lateral branch length, the number of green leaves harvested, single kernel fruits, double kernel fruits, unfilled fruits and other indicators of C₄P₄ treatment were the highest. There was no significant difference in ear diameter and 100-grain weight of corn, but the four rows of corn planting belt significantly increased the bald tip length. Therefore, C₂P₈ (2 rows of corn and 8 rows of peanut) was suitable for the strip compound planting production of corn and peanut, and C₄P₄ (4 rows of corn and 4 rows of peanut) was the worst.

【Objective】 Common smut (Mycosarcoma maydis) is a major fungal disease affecting maize production in China. This study aimed to screen for resistant germplasm resources and analyze their physiological and biochemical responses to pathogen infection, providing scientific support for disease resistance breeding. 【Method】 A total of 425 maize germplasm resources were selected and systematically screened for their resistance to common smut. Sugar metabolism, oxidative stress responses, and photosynthetic parameters were analyzed to identify high-resistant, moderate-resistant, and susceptible inbred lines. WGA-AF488/PI staining was used to analyze the hyphal proliferation to reveal the disease resistance traits of different inbred lines. 【Result】 The study found significant annual differences in the disease index and incidence of common smut in 2021 and 2022, primarily influenced by temperature and precipitation. Principal component analysis showed that the disease index on day 4, 8, and 12 post-inoculation was a key indicator of disease severity, while the disease incidence at the grain filling stage (R2) and wax ripening stage (R4) revealed differences across growth stages. Additionally, 6 high-resistance inbred lines (e.g., Q319), 67 medium-resistance inbred lines (e.g., D599), and 171 susceptible inbred lines (e.g., M407) were identified. Sugar metabolism analysis showed significant differences in sucrose, fructose, and glucose contents across inbred lines with different disease resistance, indicating the critical role of sugar metabolism in the competition between the pathogen and the host. Oxidative stress analysis revealed significant increases in H₂O₂ and O^2- contents post-infection, with the high-resistant inbred line Q319 exhibiting the strongest OH^- scavenging capacity. SOD and POD activities were significantly increased on days 4 and 8 post-inoculation, with the SOD activity of D599 increasing by 114.98% on day 8 and the SOD activity of Q319 increasing by 96.08%. On day 12, the POD activity of D599 and Q319 increased by 164.27% and 160.91%, respectively, indicating strong antioxidant defense capabilities in resistant materials. WGA staining showed that hyphal extension was limited in Q319, primarily concentrated near the vascular bundles, suggesting strong cell wall defense. D599 exhibited intermediate hyphal expansion speed and range, representing moderate defense capacity, while M407 displayed extensive hyphal spread with large intercellular infection, indicating weak cell wall defense. Post-inoculation, the net photosynthetic rate of Q319, D599, and M407 decreased by 52.5%, 52.8%, and 100.2%, respectively, compared to the control group, with significant reductions in photosynthetic pigment content; however, the decline decreased from 4 to 12 d. 【Conclusion】 This study reveals significant differences in sugar metabolism, oxidative stress responses, antioxidant capacity, and photosynthesis among different maize inbred lines under Mycosarcoma maydis infection. The high-resistance inbred line Q319 exhibits strong disease resistance through low sucrose, high fructose and glucose metabolism, along with higher chlorophyll and carotenoid content and efficient antioxidant ability. The high-susceptible inbred line M407 shows increased sucrose accumulation and insufficient antioxidant response, resulting in significantly decreased net photosynthetic rate and transpiration rate, leading to increased disease susceptibility. The medium-resistance inbred line D599 displays intermediate photosynthetic function and pigment accumulation, with disease resistance between Q319 and M407.

To explore green and high yield cultivation technology for maize in the shajiang black soil region of Northern Anhui Province, a comparative experiment on summer maize with soil testing and formulated fertilization versus conventional fertilization was conducted, using the maize variety Hangxing 007 in the shajiang black soil area of Dayang Town, Qiaocheng District, Bozhou City, Anhui Province. The experiment included 6 treatments: conventional full-fertilizer plot (ONK), soil testing and formulated full-fertilizer plot (NPK), nitrogen-free plot (PK), phosphorus-free plot (NK), potassium-free plot (NP), and unfertilized control plot (CK). The study investigated the effects of different fertilization treatments on maize agronomic traits, yield, and fertilizer use efficiency.The results showed that the NPK treatment effectively improved maize agronomic traits, with higher plant height, stem diameter, and seed setting rate, reaching 272.1 cm, 2.2 cm, and 87.2%, respectively. The yields of the treatments, ranked from highest to lowest, were NPK>ONK>NK>NP>PK>CK, with the NPK treatment achieving the highest yield of 8 981.5 kg/hm⊃2;, a 3.74% increase compared to the ONK treatment. Regarding nutrient content in maize plants and fertilizer use efficiency, the NPK treatment exhibited higher nitrogen, phosphorus, and potassium content in maize stalks, as well as higher phosphorus and potassium content in grains. The nitrogen, phosphorus, and potassium fertilizer use efficiencies under the NPK treatment were 42.64%, 21.18%, and 44.07%, respectively. The economic benefits of NPK treatment was the highest, at 14 892.6 yuan/hm⊃2;, a 5.39% increase compared to the ONK treatment. The application of soil testing and formulated fertilization technology in the shajiang black soil area of the study area can enhance the efficiency of maize fertilizer utilization, and promote maize yield and increase income.

To study the water balance during the maize growing season in Liaoning Province based on the meteorological data and crop coefficients in Liaoning Province from 1963 to 2022, the SIMETAW model and climate diagnostic analysis methods were used to analyze the precipitation, water demand patterns, and water satisfaction status during the maize growing season in Liaoning Province. The impact of regional climate change on maize water demand was revealed, and the spatio-temporal evolution of effective precipitation and water demand during the maize growing season in Liaoning Province was studied. The research results showed that the effective precipitation during the whole growth period reached 481.6 mm. Among them, it was 347.4 mm in the west, 514.9 mm in the central and southern parts, and 636.8 mm in the east. The average water demand during the whole growth period of maize was 521 mm, showing no significant downward trend. The average coupling degree between precipitation and water demand during the whole growth period of maize was 0.715, that is, precipitation met 71.5% of the water demand, and the average water shortage was 28.5%. The guarantee rate of the coupling degree λ > 0.8 in the western region was only 28.3%. The maximum value of the coupling degree appeared in the east of Liaoning Province, followed by the central and southern parts of Liaoning Province, and the minimum value appeared in the west of Liaoning Province. The highest value of the coupling degree appeared during the flowering and pollination period, followed by the trumpet stage, and the lowest value appeared in the early growth stage and the maturity stage. In recent years, the coupling degree between precipitation and water demand in the early growth stage of maize has shown a significant upward trend. The coupling degree between precipitation and water demand in the early growth stage of maize is relatively low. Therefore, it is necessary to pay attention to the occurrence of drought, especially in the western part of Liaoning Province where water resources are scarce.

A critical challenge for global food security and sustainable agriculture is enhancing crop yields while reducing chemical N inputs.  Improving N use efficiency in crops is essential for increasing agricultural productivity.  The aim of this study was to evaluate the impacts of intercropping maize with leguminous green manure on grain yield and N utilization under reduced N-fertilization conditions.  A field experiment with a split-plot design was conducted in northwestern China from 2018 to 2021.  The main plots consisted of two cropping systems: maize–common vetch intercropping (IM) and sole maize (SM).  The subplots had three N levels: zero N application (N0, 0 kg ha^–1), a 25% reduction from the traditional chemical N supply (N1, 270 kg ha^–1), and the traditional chemical N supply (N2, 360 kg ha^–1).  The results showed that the negative effects of N reduction on maize grain yield and N uptake were compensated by intercropping leguminous green manure, and the improvements increased with cultivation years.  The integrated system involving maize–leguminous green manure intercropping and a reduced N supply enhanced N translocation from maize vegetative organs to grains and increased the nitrate reductase and glutamine synthetase activities in maize leaves.  The supercompensatory effect in maize leaves increased year by year, reaching values of 16.1, 21.3, and 25.5% in 2019, 2020, and 2021, respectively.  These findings suggest that intercropping maize with leguminous green manure under reduced chemical N input can enhance N assimilation and uptake in maize.  By using this strategy, chemical fertilizer is effectively replaced by leguminous green manure, thereby improving N use efficiency and maintaining stable yields in the maize-based intercropping system. 

To screen out the antagonistic bacteria of the maize stalk rot pathogen (Fusarium graminearum), pure culture techniques were used to isolate microorganisms from soil samples collected from 4 regions. Isolated strains were screened via plate antagonism assays, and the antagonistic strains were further characterized by their physiological and biochemical properties (including carbon source metabolism, enzyme activity, etc.) and subjected to molecular identification. The results indicated that there were differences in the diversity distribution of culturable microorganisms in the soils of the four regions, among which the microbial communities in the soils of various plots in Guangdong Province were more diverse. A total of 129 bacterial strains were isolated from the soil samples of the 4 regions, including 100 Gram-positive strains and 29 Gram negative strains, with most displaying rod-shaped morphology. Through plate confrontation assays, 11 bacterial strains with antagonistic activity against maize stalk rot were screened from the 129 isolates. Physiological and biochemical characterization revealed significant differences among the antagonistic strains in metabolic patterns, enzyme activities, and Gram properties, although some indicators (e.g., ONPG test, organic phosphorus solubilization test) showed high consistency. The results of phylogenetic analysis indicate that strains with strong antagonistic activity against maize stalk rot included Burkholderia cepacia, Pantoea, and Enterobacter hormaechei. Phylogenetic analysis demonstrated a close genetic relationship between Enterobacter hormaechei and Pantoea. In conclusion, this study successfully screened and identified strains of Burkholderia cepacia, Pantoea, and Enterobacter hormaechei, which exhibit strong antagonistic activity against maize stalk rot (Fusarium graminearum), showing potential for development as biocontrol agents.

This study aimed to reveal the influence of the morphology and internal structure of corn kernel on its breakage resistance, providing a theoretical basis for the selection and breeding of corn cultivars suitable for mechanical grain harvesting. ‘DH618’, ‘DK159’ and ‘HM1’ were selected as tested cultivars, the morphological and structural parameters of kernel were obtained by CT scanning while kernel breaking force was measured by static compression test. The kernel of ‘DH618’was the largest in length (6.85-14.03 mm), thickness (4.22-7.64 mm) and volume (74.16-313.79 mm³), the proportion of its embryos in kernel was also the highest (10.49%-11.26%). The kernel of HM1 had the largest grain width (5.71-8.75 mm) and the highest subcutaneous cavity ratio (1.26%-2.05%). The relationship between the morphology, structure of corn kernel and its mechanical properties was identified, which would provide an essential reference for the study of corn kernel’s characters and conduce to the selection and breeding of corn cultivars favoring mechanical grain harvesting.

This study investigated the ecological adaptability of different efficiency-enhanced DAP fertilizers in soil of Xinjiang, aiming to identify novel DAP fertilizers with lower nutrient content that promote the growth of maize in Xinjiang. The research provided a reference for the selection and application of DAP fertilizers for maize in Xinjiang, while also offered a basis for cutting-edge research on low-nutrient, high-efficiency fertilizers in the region. Using 64% DAP without additives (high-nutrient fertilizer) as the control, comparisons were made with low-nutrient fertilizers, including 57% DAP with additive (formula A), 57% DAP with additive (formula B), 57% DAP with additive (formula C), 57% DAP with additive (formula D), 57% DAP with additive (formula E), and 57% DAP with additive (formula F). The growth morphology, physiological indicators and biomass of maize under different treatments were measured, and statistical methods such as regression analysis were applied to evaluate the results. The results showed that the addition of efficiency-enhancing additives promoted root development in maize plants and improved physiological indicators such as chlorophyll content and plant height. Low-nutrient DAP fertilizers with additives showed a tendency to outperform high-nutrient DAP fertilizers in promoting maize growth. The effects varied among different additive formulations, with formula A, formula E, and formula F demonstrating the most significant promotion effects on maize growth.

The aim of this study is to investigate the effects of tillage practices on soil properties, aggregate stability and soil quality, providing references for improving soil fertility and yield in drip-irrigated maize fields in Xinjiang. A field positioning experiment was conducted in Areoletuohai Ranch, Bole City, Xinjiang from 2022-2023 with the maize variety ‘Jinli1702’ as the test material. Four tillage treatments were set up, including conventional tillage with plastic film (CT), conventional tillage without plastic film (BT), no-tillage (NT) and shallow tillage (ST). The changes in soil properties, aggregate fractions and maize yield were analyzed to evaluate the effects of tillage practices on soil quality and maize yield. The results showed that compared with CT, both NT and ST significantly increased >2 mm aggregate contents, mean weight diameter (MWD), geometric mean diameter (GMD), and R_0.25 (P<0.05), indicating improved soil aggregate stability. Under the CT, soil temperature and moisture content were significantly higher than that in the NT and ST. Soil bulk density ranged from 1.35 to 1.70 g/cm³, with NT and ST showing significantly higher levels of available phosphorus, total nitrogen and organic carbon compared to CT. The soil quality index (SQI) in NT and ST increased by 19.82% and 15.29%, respectively, compared to CT. Maize yield under NT and ST was significantly higher than under CT and BT, reaching 20.67 t/hm² and 19.84 t/hm², respectively. But, there were no differences in ear grain number across four treatments, while the thousand-grain weight of NT was significantly higher than that of the others (P<0.05). Mantel analysis revealed significant positive correlations between yield and aggregate stability indices (MWD, GMD, D and R_0.25), soil properties, and SQI. Structural equation modeling showed that tillage practices affected soil quality by altering soil aggregate stability and soil properties, thereby indirectly influencing maize yield. The results showed that the yield of NT and ST increased by 9.13 % and 4.75 % compared with conventional tillage in drip irrigation maize farmland in Xinjiang, which had a significant effect on soil structure stability, soil quality and maize yield.

In order to study the impact of climate change on the growth of spring corn in the Loess Plateau of eastern Gansu, the continuous 30-year climate factors and corn biological observation data from Xifeng in 1994-2023 were used to analyze facts of climate warming and humidification in eastern Gansu and their impact on corn by using linear regression, polynomial function, climate trend rate and other methods. The results showed that, over the past 30 years, the heat and precipitation during the growth period of spring corn in eastern Gansu had shown an increasing trend, while sunshine had shown a decreasing trend. The climate warming and humidification trend in the Loess Plateau of eastern Gansu was obvious, which had a significant impact on the growth and development of corn. Climate warming affected the growth cycle of corn, the sowing period of corn was delayed, the maturity period was advanced, the growth was shortened, and the planting boundary was expanded northward; climate warming and humidification made the growth height of corn, leaf area index, ear length, hundred grain, plant seed weight, theoretical yield and other indicators showed an increasing trend, and the positive effect of climate warming and humidification on the production of spring corn and agricultural in the Loess Plateau of eastern Gansu was significant. The yield of corn in the Loess Plateau of eastern Gansu was negatively correlated with average temperature, effective accumulated temperature and sunshine hours during the growth period, and was extremely significantly positively correlated with the precipitation during the growth period. The lack of water was the main limiting factor for the growth of crops in the Loess Plateau of eastern Gansu. Moisture affected the whole process of corn yield growth. The yield of corn was mainly affected by the amount and distribution of precipitation. In production, we should fully tap the potential of climate resources, adjust the planting, promote the scientific planting mode, introduce high-yielding and stress-resistant varieties, select the appropriate sowing period, dynamically increase or decrease the area of multiple cropping, water-saving irrigation, improve the disaster prevention and reduction system, control and prevent to improve quality and efficiency, and avoid harm to reduce the negative effects of climate change.

To further explore technical measures suitable for soil improvement in saline alkali land in the Yellow River Diversion irrigation area of Ningxia, the ‘Ximeng XM1618’ maize variety was used as the experimental material, and soil remediation agents with different dosage gradients were set up on the basis of unified base fertilizer for experimental study, including fertilizer (CK), fertilizer +150 kg/hm² soil remediation agent (T1), fertilizer +300 kg/hm² soil remediation agent (T2), fertilizer +450 kg/hm² soil remediation agent (T3), fertilizer +600 kg/hm² soil remediation agent (T4), the growth and development of maize and soil physical and chemical properties were comprehensively evaluated. The results showed that in terms of maize growth and development, T4 treatment had the highest relative growth rates of plant height and stem diameter, which were 25.47% and 51.43% higher than CK, respectively; in terms of chlorophyll content, both T3 and T4 treatments significantly increased the chlorophyll content of maize leaves throughout the entire growth period; in terms of soil physical and chemical properties, the soil pH and total salt content of T2, T3, and T4 treatments were significantly lower than those of CK; the soil organic matter (14.3 g/kg), total nitrogen (92 g/kg), available nitrogen (197 mg/kg), available phosphorus (71 mg/kg), and available potassium (222 mg/kg) contents of T4 were significantly higher than those of CK, increasing by 17.21%, 16.46%, 149.37%, 36.54%, and 96.46%, respectively; in terms of yield and economic benefits, with the increase of soil remediation agent dosage, maize yield had increased. The yield of T4 treatment (11 400 kg/hm²) was the highest, increasing by 23.69% compared to CK; the optimal comprehensive ranking in principal component membership function analysis was achieved through T4 processing. Considering the impact and benefits on the soil environment, it is recommended to apply 600 kg/hm² of soil remediation agent when planting maize in saline alkali land in the Yellow River Diversion irrigation area of Ningxia, which can effectively improve the soil environment of saline alkali land, increase maize yield and income.

To understand the yield and fertilizer use efficiency of maize under formula fertilization by soil testing conditions, the experiment established five treatments:soil testing and formulated fertilization (NPK), soil testing and formulated fertilization without nitrogen (PK), soil testing and formulated fertilization without phosphorus (NK), soil testing and formulated fertilization without potassium (NP), and no fertilization (CK). The maize yield, yield components, and total nitrogen, phosphorus, and potassium content under different fertilization conditions were measured, and nitrogen, phosphorus, and potassium fertilizer use efficiency as well as input-output ratio were calculated.The results showed that the NPK treatment had the highest values for ear number, kernel number per ear, 100-kernel weight, and actual yield, reaching 2 928.5 ears/666.7 m⊃2;, 567.8 kernels, 35.2 g, and 585 kg/666.7 m⊃2;, respectively. NPK treatment the total nitrogen, phosphorus, and potassium content in maize grains and straw were 9.20%, 3.42%, 5.53% and 10.10%, 3.80%, 14.4%, respectively. The nitrogen, phosphorus, and potassium fertilizer use efficiency reached 42.26%, 24.38%, and 48.32%, respectively. The input-output ratios for NPK, PK, NK, NP, and CK were 5.33, 4.15, 5.18, 5.25, and 4.58, respectively. These results indicated that the soil testing and formulated fertilization in this experiment effectively improved maize yield and production investment ratio.

The maize production practice in Anhui region was combined, to explore the occurrence patterns of high temperature in summer maize in the area, the impacts of high temperature heat damage on summer maize were summarized, and mitigation measures were constructed. The high frequency period of high temperature and heat damage in the research area was from June 1st to August 10th. High temperature stress can cause damage to the nutritional and reproductive growth of maize, manifested as weak plant growth, decreased photosynthetic capacity, Pollen inactivation, poor pollination and fertilization, obstructed grain filling, and decreased quality. The measures to alleviate high temperature damage to summer maize include actively selecting and applying heat-resistant varieties; adjusting the broadcast schedule to avoid exhaling during periods of frequent high temperatures; irrigation during high temperature period to improve the microclimate in the fields; lightly tap the male ear with a bamboo pole or use a drone to assist in pollination; spraying chemical regulators such as CaCl₂ to improve the heat resistance of plants. This article provides a reference for the high and stable yield of summer maize in relevant regions.

The parental sources, breeding process, variety characteristics, seed production techniques, and high yield cultivation techniques of maize variety Zhongxu No.1 were summarized and analyzed. This variety was cultivated with ZF428 as the female parent and ZX410 as the male parent. It was approved by the Anhui Provincial Crop Variety Approval Committee in 2024 (approval number: Wanshenyu 2024T004). This variety was planted in the north of the Huai River in Anhui Province, and had the characteristics of good field growth, excellent quality, strong resistance, and high yield. The key points of its seed production technology include selecting plots with good water conservancy conditions and flat terrain as seed production bases; strictly set up isolation zones through methods such as spatial and temporal isolation; staged impurity removal treatment to eliminate mixed seedlings in the field; adopting the method of touching the buds with leaves to remove the male spikes from the maternal plant; reasonably arrange the parent line ratio and sowing schedule; predicting the flowering period and adjust it using chemical and physical methods to ensure that the flowering periods meet; timely harvest and separate storage to prevent mixing. High yield cultivation techniques include selecting suitable plots for light, temperature, fertilizer, and water conditions for planting; sow at the appropriate time and sow content; adopting a single seed sowing machine to ensure reasonable seedling density; soil sealing and weed control before sowing, chemical weed control during the 3-5 leaf stage; apply sufficient basal fertilizer, apply timely topdressing during the bell mouth and pollination periods, and supplement zinc, boron, and other trace element fertilizers in moderation; timely irrigation and timely drainage of accumulated water in the fields; adopting appropriate pesticides to prevent and control pests and diseases such as ground tiger, maize borer, rust, etc.; harvest maize kernels promptly when the milk ripening line completely disappears. This article provides a reference for further promotion and planting of this variety.

Due to their sessile nature, plants require strong adaptability to complex environments, with stress tolerance often associated with trade-offs in growth and development (Major et al. 2020).  This antagonistic relationship between defense and growth has been interpreted as a competition for limited resources that are allocated to defense at the expense of growth, or vice versa. Recent studies have demonstrated that hormone-based signaling networks trigger transcriptional changes in key genes, leading to trade-offs between growth rates and stress defense (Huot et al. 2014).  Several genes involved in biotic and abiotic stress response have been identified.  These genes contain nonsynonymous variants that show convergent changes in allele frequency across different breeding eras in both China and the United States (Wang et al. 2020), which may reflect the selection of biotic and abiotic stress response genes during modern maize breeding.

Transcription factors (TFs) play vital roles in regulation of gene expression in plant cells, with specific key TFs exhibiting multifunctionality by coordinating various regulatory pathways to promote plant growth (Hufford et al. 2021).  Jasmonates (JAs) are identified among phytohormones for their significant roles in regulating various plant processes, particularly in defense mechanisms against pests. MYC2 is a central transcription factor that orchestrates the JA signaling pathway and defense responses in plants by regulating the expression of numerous genes (Du et al. 2022).  Although MYC2 has been extensively characterized in Arabidopsis, studies in crops have revealed the complexity of MYC2’s function, with reports addressing different aspects, such as growth in wheat (Li et al. 2023) or stress defense in maize (Ma et al. 2023).  However, lack of systematic understanding of the complex regulatory network of MYC2 in crops, particularly in maize constrain the further utilization of MYC2 and its downstream genes in maize genetic modification for breeding elite varieties.  Here, we reported that ZmMYC2 had undergone selection during domestication and modern breeding; it acts as a key regulator of the trade-off between development and defense gene expression in maize, elucidating its regulatory network, which holds significant importance in balancing yield and resistance.

Given that some resistance genes have been selected during modern breeding, we analyzed the history of ZmMYC2 over the processes of maize evolution and artificial selection.  According to maize Haplotype Map v3 (HapMap3) database consisting of 1164 modern maize accessions, 25 landraces, and 21 teosintes (Zea mays. parviglumis) (Bukowski et al. 2018), nucleotide diversity strongly decreased sharply at the promoter region (2000 bp upstream of transcription start site) of ZmMYC2 during breeding, while the coding region and 3’-downstream region of ZmMYC2 showed less dramatic changes in nucleotide diversity changes (Fig. 1-A).  Thus, we hypothesize that the genetic diversity within the promoter region of ZmMYC2 has decreased during the breeding process, with favorable variations being selected.  Moreover, the frequency of three polymorphisms underwent convergent changes during modern breeding in both the United States and China (Fig. 1-B–D).  These three polymorphisms constituted three principal haplotypes: pZmMYC2^Hap1, pZmMYC2^Hap2, and pZmMYC2^Hap3, of which the frequency of pZmMYC2^Hap1 showed an increasing trend during modern maize breeding (Fig. 1-E).  The rare haplotype pZmMYC2^Hap3 (n=4) emerged only during the breeding era of China in 2000.  LUC signal activity for pZmMYC2^Hap3 was significantly lower than that of the other two haplotypes in the promoter region (pZmMYC2^Hap1, pZmMYC2^Hap2) (Fig. 1-F–H), suggesting a differential regulatory potential among the haplotypes.  These data indicate that ZmMYC2 was under-selected during maize evolution and breeding processes of maize.  Next, we investigated the expression level of genome-wide association studies of ZmMYC2 based on 368 maize inbred lines using RNA-seq and genome resequencing data (Fu et al. 2013; Li et al. 2013).  The results showed a strong peak signal containing the genomic region of ZmMYC2 on chromosome 1 (Fig. 1-I).

To mine the genes downstream of ZmMYC2, we performed protoplast transient expression-based RNA-sequencing (PER-seq) analysis to facilitate the discovery of new downstream genes utilizing a consistent protoplast system (Zhu et al. 2023).  In total， 281.6 million clean reads were generated, among which an average of approximately 87% of reads were mapped uniquely to the reference genome (Appendices A and B).  The results demonstrated a significant increase in the expression level of ZmMYC2 in each of three replicates of the pRTL2-ZmMYC2-GFP (MYC2-GFP) construct, exceeding a 500-fold increase compared to the pRTL2-GFP-empty (GFP-empty) construct (Fig. 1-J).  Furthermore, upon analyzing differentially expressed genes (DEGs) with a false discovery rate (FDR) <0.05 as the threshold, it was found that 4480 unique DEGs of MYC2-GFP, among which 2,677 were up-regulated compared to GFP-empty (Appendix C).  These up-regulated genes are enriched in circadian rhythm, cell cycles, plant growth, and in response to stress, indicating that these genes are regulated directly or indirectly by ZmMYC2 (Appendix D-A–B).

Several potential candidate genes were selected in an unbiased manner based on their log₂(fold-change) ≥2.5 (Fig. 1-J).  Gene expression profiling analysis of ZmMYC2 and its potential targets revealed essential coincidence (Appendix E).  The interaction between MYC2 and targets observed in the PER-seq system, were further confirmed through expression quantitative trait loci (eQTL) analysis, dual-luciferase reporter assay (DLR), and electrophoretic mobility shift assay (EMSA).  Among the target genes, the members of cytochrome P450 (CYP) gene family are widely distributed in plants involving in various biological processes, such as detoxification of xenobiotics, secondary metabolites production, and terpenoid synthesis (Chakraborty et al. 2023; Sun et al. 2024).  Our results identified an unreported gene of cytochrome P450 family ZmCYP709H1 as a target of ZmMYC2.  Additionally, eQTL analysis of ZmCYP709H1 revealed a strong trans-eQTL signal in the region of chromosome 1, which contains the genomic region of ZmMYC2 (Fig. 1-K).  Subsequent validation through DLR and EMSA confirmed that ZmMYC2 interacts with the promoter region of ZmCYP709H1 and stimulates its expression (Fig. 1-L; Appendices F-A and G-A).  Moreover, the transcriptional activation effect of ZmMYC2 on the promoter of ZmCYP709H1 was suppressed by ZmJAZ8 (Fig. 1-L).  A recent report showed reduced expression of ZmCYP709H1 in three maize dwarf mutants compared to the wild-type, reflecting its potential role in regulating growth, particularly plant height.  This result supports our proposed function of the ZmMYC2-ZmCYP709H1 model (Gao et al. 2024).  Additionally, two other CYP genes, ZmBX5 and ZmBX6, were identified as potential downstream genes of ZmMYC2 that participate in benzoxazinoid synthesis, which is consistent with the findings of a previous study (Ma et al. 2023).  We further confirmed that ZmMYC2 can physically bind to the promoter region of these two genes and activate their expression (Appendix H-A–F).  Besides, the result showed that ZmMYC2 can activate ZmBRD1 expression, which is a member of the CYP gene family and responsible for the final step of brassinosteroid synthesis (Tian et al. 2019) (Fig. 4-A and B; Appendix I-A–D).

The AUXIN RESPONSE FACTOR (ARF) family consists of plant-specific TFs that are key regulators of gene expression in response to the plant hormone auxin (AUX), and participated in various developmental processes such as vascular tissue differentiation, root and shoot development, and environmental stimuli responses (Hagen and Guilfoyle 2002; Salmon et al. 2008).  However, little evidence has been found to support the regulation of ARF gene expression by the core factor ZmMYC2 in the JA signal transduction pathway in maize.  Our data showed that the expression of ZmARF3 was regulated by a trans-eQTL signal involving the gene region of ZmMYC2 (Appendix F-B).  In addition, ZmMYC2 can bind to the promoter region of the ZmARF3 gene and activate its transcription (Fig. 1-M; Appendix G-B).  Besides, MYC2 can activate expressions of senescence-associated genes in rice and wheat, which could be repressed by physical interactions with TaARF15-A1 (Li et al. 2023).  These data demonstrate the key role of MYC2 in regulating the stress resistance and growth of maize through the synergistic regulation of JA and AUX hormone signaling pathways.

Tonoplast intrinsic proteins (TIPs), a subgroup of the aquaporin family, are integral membrane proteins that are crucial for transporting water and small solutes across cellular membrane to maintain water balance (Chaumont et al. 2001).  We found that ZmTIP3c was activated by ZmMYC2 (Fig. 1-N; Appendices F-C and G-C), which supports the potential role of ZmMYC2 in jointly regulating drought stress and JA signal transduction.  The CER2 gene, which is a member of the ECERIFERUM family, is critical for the synthesis of epicuticular wax (Bourdenx et al. 2011; Zhao et al. 2024).  A recent study demonstrated that wounding-induced wax accumulation was primarily regulated by the JA signaling pathway in Arabidopsis, suggesting the potential of JA signaling in wax synthesis (Huang et al. 2024).  We identified ZmCER2 as a ZmMYC2 target (Fig. 1-O; Appendices F-D and G-D).  Additionally, we confirmed the upregulation of ZmCER2 in response to drought stress in five elite inbred lines representing distinct heterotic groups of maize (Fig. 1-P), as observed by previous studies (Zhang et al. 2018, 2020; Jiang et al. 2023).  The result indicates that the drought-induced trait of ZmCER2 can be observed across different genetic backgrounds, thus supporting the potential role of ZmMYC2 in modulating JA signaling and response to drought stress in maize mediated by ZmCER2.

In summary, our findings support the selection of ZmMYC2 during domestication and breeding, highlighting its critical role in regulating genes involving plant growth and development.  Collectively, our eQTL, DLR, and EMSA data successfully validated several targets (ZmCER2, ZmARF3, ZmBRD1 ZmTIP3c, ZmCYP709H1, ZmBX5, and ZmBX6) of ZmMYC2, that encode diverse proteins and participate in various metabolic pathways (Fig. 1-Q).  Of these, ZmCER2 was confirmed to be induced by drought stress and activated by ZmMYC2, suggesting that ZmMYC2 may play a role in the drought response by regulating synthesizing epicuticular wax.  These findings underscore the diverse functions of ZmMYC2 in maintaining the balance between plant development and defense-response, primarily via the JA signaling pathway.  Our data represent a foundation for the further function and mechanism elucidation of of ZmMYC2 and its “Yin-Yang” roles in regulating plant defense and growth (Fig. 1-Q).  Given the crucial role of ZmMYC2 in balancing development and resistance, further work is needed to confirm to unlock the full potentials of ZmMYC2 in mediating yield and resistance through JA signaling pathway by exploring the function of those downstream targets, which is a significant step toward crop precision breeding. 

Crude fat is an important nutritional component of maize kernels.  However, the genetic mechanisms underlying crude fat content in maize kernels remain elusive.  Previous studies used single-model genome-wide association studies (GWAS) with limited population sizes, which can result in false positives of loci and hinder the identification of functional genes.  Therefore, this study used a population consisting of 495 maize inbred lines, combined with 1.25 million single nucleotide polymorphisms (SNPs), and implemented GWAS using six models to identify quantitative trait nucleotides (QTNs) controlling crude fat content and to mine key genes.  The results revealed a wide variation in crude fat content (0.62–16.03%) and broad-sense heritability (96.23%).  In total, 744 significant QTNs were detected, with 147 co-located across different models, environments, and methods.  Based on the 147 co-located QTNs, candidate genes were searched at 50 kb up- and downstream intervals of each QTN.  We finally screened eight candidate genes (GRMZM2G169089, GRMZM2G117935, GRMZM2G002075, GRMZM2G368838, GRMZM2G058496, GRMZM2G090669, GRMZM2G001241, and GRMZM2G333454) related to crude fat content that exhibited high expression levels during kernel development in maize inbred line B73.  Notably, GRMZM2G169089, GRMZM2G117935, GRMZM2G002075, and GRMZM2G368838 are involved in the linoleic acid metabolic pathway, oil metabolism, kernel growth, and development in maize.  Furthermore, co-expression network analysis revealed that the eight candidate genes exhibited strong correlations with 30 known genes.  Proteins encoded by candidate genes interact with various other proteins and play an important role in oil content and oleic acid metabolism in maize kernels.  The best haplotypes of candidate genes might increase crude fat content without decreasing maize yield.  These results broaden the understanding of the genetic mechanism of crude fat content and facilitate marker-assisted selection for high-crude fat breeding programs for maize.

Southern corn leaf blight (SCLB) caused by Cochlibolus heterostrophus, is a widespread foliar disease that has a substantial impact on maize yield in the Huanghuaihai region of China. Pydiflumetofen (Pyd), a new succinate dehydrogenase inhibitor (SDHI), has been found as a promising fungicide for the efficient control of SCLB, however, resistance of C. heterostrophus to Pyd has not been studied well. Here, five Pyd-resistant mutants were generated through fungicide adaptation. Sequence alignment analysis revealed that these mutants primarily mutated in ChSdhB and ChSdhD, with 3 genotypes: ChSdhB^H277Y, ChSdhB^I279T and ChSdhD^H133Y, exhibiting two distinct categories of resistance: high resistance (HR) and moderate resistance (MR), which resistance factors (RF) is 214.22 and 44.33-53.67, respectively. These mutants were more pathogenic than the wild-type parental strains, but there was a significant reduction in mycelial growth rate and sporulation in the resistant mutants, indicating a significant fitness cost associated with resistance to Pyd. In addition, this study revealed a positive cross-resistance between Pyd and another SDHI fungicide cyclobutrifluram. However, no cross-resistance was found between Pyd and other classes of fungicide, including prochloraz, fludioxonil, iprodioneand pyraclostrobin. Homology modeling and molecular docking further confirmed that point mutation of ChSdhB^H277Y, ChSdhB^I279T, and ChSdhD^H133Y could reduce binding affinity between Pyd and its target subunits from −74.07, −74.07, −152.52 kcal mol^-1 to −3.90, −4.95, −9.93 kcal/mol, respectively. These findings not only provided valuable insights for managing SCLB caused by C. heterostrophus, but also enhanced our understanding of molecular mechanism underlying plant pathogen resistance to Pyd.

In order to clarify the occurrence pattern of pests, diseases, and weeds in the strip intercropping area of soybean and corn in the Huang-Huai-Hai region, and screen the optimal control plan, the experiment was conducted in Fangsi town of Yucheng County, Dezhou City, Shangdong Province. Using soybean ‘Qihuang 34’ and corn ‘Zhengdan 958’ as the test materials, this experiment designed to use different combinations of pesticides in each growth stage of soybean and maize for control, and the control effect of the combination on pests and weeds and the safety of soybean and maize were determined. The results showed that 35% fumediridinrustyl thiamethoxam microcapsule suspension seed coating, 30% pyraclostrobin pentazole suspension, 28% propylcyclamideazoxylamin suspension emulsion, 45% refined metolachlor and flumethachlor microcapsule suspension-suspension, 25% high-efficiency cyhalothrin microcapsule suspension and 15% azolamide and tick urea suspension were safe for soybean and corn at different growth stages. Before sowing of soybean and corn, 35% formethoxin and chlorfenaz microcapsule suspension seed coating agent were used, 30% pyraclostrobin pentazole suspension and 25% high-efficiency cyhalothrin microcapsule suspension were sprayed at the seedling stage, and 30% pyraclostrobin pentazole suspension was sprayed at the mature stage, and after spraying 30% pyraclostrobin pentazole suspension, 28% propylpyroxystrobin suspension emulsion, and 15% azolamide and tick urea suspension at the seedling stage, the control effect of soybean and corn disease was 41.72%-65.21%, and the pest control effect was 83.78%-88.16%. After sowing soybean and corn, 45% fine metolachlor microcapsule suspension and 33% refined metolachlor and propargylfluchlor microcapsule suspension-suspension were sprayed before seedlings, and the control effect of weeds in the field was 87.58%-90.77%. In summary, this combination of agents can effectively control the occurrence of pests and weeds in soybean and corn, and has no obvious impact on the growth of soybean and corn, and has high economic benefits.

In the banded compound planting pattern of soybean and maize, choosing the suitable field configuration is crucial to improve the soybean yield. In order to further explore the reasonable field configuration of soybean and maize, four types of configurations are set, namely 2M2S, 2M4S, 2M6S, 3M4S (M for corn and S for soybean). Using monoculture soybean (SS) and monoculture corn (SM) as controls, intercropping soybean yield, dry matter accumulation and distribution, and plant morphology were studied. The results showed that the yield of each corn was SM > 2M2S > 2M4S > 3M4S > 2M6S. The yield of intercropping corn was 3.22%-20.23% lower than that of single planting corn. The yield of intercropping soybean was 40.18%-60.5% lower than that of single cropping soybean. The yield of soybean in each configuration from high to low was SS > 2M6S > 2M4S > 3M4S > 2M2S. The yield of soybean in 2M6S configuration increased by 18.88%-51.47% compared with other intercropping configurations. In each intercropping configuration, with the increase of soybean rows, soybean SPAD, leaf area index (LAI) and stem thickness all increased, and the plant height decreased. The leaf SPAD content of 2M6S soybean increased by 0.55% to 7.63% compared with other intercropping configurations. The soybean leaf area index (LAI) of the 2M6S configuration was 9.02%-69.59% higher than that of other intercropping configurations. The soybean stem thickness of the 2M6S configuration was 4.76% to 23.94% higher than that of other intercropping configurations. Compared with monoculture soybean, the plant height increased by 17.52% to 37.50%, and the height of soybean strain in 2M2S configuration was higher than that in other intercropping configurations. The quantitative results of soybean agronomic traits and yields under different configurations of banded compound planting of soybean and maize can provide a basis for screening configurations.

The study aimed to explore the impact of the coupling of different cultivation and fertilization measures on the corn productivity of acidified soil in rocky desertification areas, providing a basis for the improvement of acidified soil and crop yield increase in rocky desertification areas. In 2023, a soil acidification improvement experiment was carried out in Muzhe Village, Xichou County, Wenshan Zhuang and Miao Autonomous Prefecture, Yunnan Province. The experiment included the following treatments: (1) fertilization measures: no fertilization (NK), chemical fertilizer (CK); (2) cultivation measures: intercropping of maize and soybean (INT); (3) coupling of cultivation and fertilization measures: technology integration (TI). There were 3 categories with 4 treatment measures in total to study the impact of the coupling of cultivation and fertilization measures on soil improvement, maize yield, maize nitrogen, dry matter accumulation and distribution, as well as the impact of environmental factors on maize yield. The results showed that at the harvest stage, the soil pH of TI, INT, NK and CK treatments were pH 6.12, 6.03, 6.02 and 5.97, respectively. The maize grain yields of TI, INT, CK and NK treatments were 10321.44, 9760.92, 8116.14 and 5732.18 kg/hm², respectively. The TI and INT significantly (P<0.05) increased the maize yield per unit area, while no fertilization significantly (P<0.05) decreased the maize yield. The proportion of grain nitrogen in above-ground nitrogen for INT, TI, and CK treatments was 50.25%, 50.91% and 57.39%, respectively. The proportion of grain dry matter in above-ground dry matter for INT, TI, and CK treatments was 49.19%, 51.40% and 54.13%, respectively. The trends of nitrogen distribution ratio and dry matter distribution ratio were the same for INT, TI, and CK treatments. The factors affecting crop yield were different at different growth stages of the crop. At the maize seedling stage, the factors affecting yield were nitrate nitrogen content, soil pH and ammonium nitrogen content, with explanatory degrees of 76.4%, 7.8% and 6.6%, respectively. At the vigorous vegetative growth stage of maize, the factors affecting yield were available phosphorus content and available potassium content, with explanatory degrees of 76.9% and 12.4%, respectively. At the reproductive growth stage of maize, the available potassium content, as a factor affecting yield, had an explanatory degree of 59.6%. The following conclusions could be drawn: (1) maize-soybean intercropping could increase the maize yield per unit area. The coupling of cultivation and fertilization measures could further increase the yield by increasing the proportion of dry matter distributed to grains, and could significantly increase the soil pH. (2) Intercropping would reduce the nitrogen transfer ratio of the above-ground vegetative organs of maize plants and weaken the contribution rate to grain nitrogen accumulation. Compared with intercropping, the coupling of cultivation and fertilization measures could increase the nitrogen transfer ratio of the above-ground vegetative organs of maize plants and the contribution rate to grain nitrogen accumulation. (3) Crops had different fertilizer requirements at different growth stages. Maize was sensitive to soil pH, ammonium nitrogen and nitrate nitrogen content at the seedling stage; it was sensitive to soil available phosphorus and available potassium content at the vigorous vegetative growth stage, and it was sensitive to soil available potassium content at the reproductive growth stage.

To investigate the trends of meteorological elements at different growth stages of maize in Shenyang and their impact on meteorological yield, the Mann-Kendall test was employed to analyze the mean values of four meteorological elements (i.e., air temperature, precipitation, relative humidity, and wind speed) during the sowing, jointing, tasseling-milk, and maturity stages and annual meteorological yield from 2000 to 2021. The impact of climate change on the meteorological yield of maize was studied. Results showed that there was no significant trend in air temperature during the sowing and jointing stages. Before 2017, there was a downward trend during the tasseling-milk stage, followed by an upward trend. Before 2008, there was an upward trend during the maturity stage, followed by a downward trend. Precipitation showed an upward trend during the sowing and tasseling-milk stages, while there was no significant trend during the jointing and maturity stages. The relative humidity showed no significant trend during the sowing stage, while it exhibited an increasing trend during the jointing, tasseling-milk, and maturity stages. The wind speed showed a decreasing trend in all four stages. In years with higher meteorological yields, air temperature and precipitation during the four stages were generally higher, relative humidity was higher during the jointing and tasseling-milk stages, and wind speed was slightly lower during the four stages. In years with lower meteorological yields, air temperatures were slightly lower during the growth stages except the sowing stage, precipitation was excessively high, relative humidity was slightly higher during the tasseling-milk and maturity stages, and wind speed was excessively low. Based on the Pearson correlation coefficient, the main influencing factors selected were precipitation and relative humidity during the sowing stage, wind speed during the jointing stage, precipitation during the tasseling-milk stage, and temperature and wind speed during the maturity stage. Based on the above factors and the random forest algorithm, a meteorological yield prediction model was constructed, which could effectively simulate the trend of meteorological yield. This study can provide the theoretical basis for maize industry management, risk assessment, and agricultural sustainable development in Shenyang.

In order to comprehensively understand the production characteristics and application value of the national approved maize variety ‘Xundan 996’, the high yield, stability and adaptability of ‘Xundan 996’ were statistically analyzed by means of yield average, coefficient of variation, high stability coefficient, and regression coefficient using the data of the regional test and production test in Huang-Huai-Hai summer maize area from 2019 to 2020. The results showed that the average regional trial yield and production trial yield of ‘Xundan 996’ were 10431.8 kg/hm² and 9904.5 kg/hm², increasing by 3.6% and 4.6% compared with the control‘Zhengdan 958’, respectively. In the 2-year regional test, the coefficient of variation of yield was 16.73% and 12.91%, both lower than the control. The high stability coefficients were 78.29% and 82.21%, respectively, which were both higher than the control. The regression coefficients were 0.9440 and 0.9398, which were both less than 1 and lower than that of the control. The yield increase rates were 64.1% and 82.1%, respectively. Meanwhile, the trial results indicate that ‘Xundan 996’ has good lodging resistance, disease resistance, and high temperature tolerance. Comprehensive analysis shows that ‘Xundan 996’ is a new maize variety with high and stable yield, wide adaptability, and strong stress resistance, which is suitable for large area planting in the summer maize area of Huang-Huai-Hai.

The application of organic fertilizers has become an increasingly popular substitution in maize production to reduce gaseous nitrogen (N) loss and soil degradation caused by inorganic fertilizers.  Organic fertilizer plays a key role in improving soil quality and stabilizing maize yields, but studies that refine different substitution rates remain poorly documented.  A field study was carried out in 2021 and 2022 based on a long-term trial initiated in 2016.  The experiment included five organic fertilizer N substitution rates with equal input of 200 kg N ha^–1: 0% organic fertilizer (T1, 100% inorganic fertilizer), 50.0% organic+50.0% inorganic fertilizer (T2), 37.5% organic+62.5% inorganic fertilizer (T3), 25.0% organic+75.0% inorganic fertilizer (T4), 12.5% organic+87.5% inorganic fertilizer (T5), and no fertilizer control (T6).  The average result of two years showed that T3 and T1 had the highest grain yield and biomass, respectively, and there was no significant difference between T1 and T3.  Compared with T1, 12.5, 25.0, 37.5, and 50.0% substitution rates (T5, T4, T3, and T2) significantly reduced total nitrogen loss (NH₃、N₂O) by 8.3, 16.1, 18.7, and 27.0%, respectively.  Nitrogen use efficiency (NUE) was higher in T5, T3, and T1, and there was no significant difference among them.  The organic fertilizer substitution directly reduced NH₃ volatilization and N₂O emission from farmland by lowering ammonium nitrogen and alkali-dissolved N content and by increasing soil moisture.  These substitution treatments reduced N₂O emissions indirectly by regulating the abundance of AOB and nirK-harboring genes by promoting soil moisture.  The 37.5% of organic fertilizer substitution reduces NH₃ volatilization and N₂O emission from farmland by decreasing ammonium nitrogen and alkali-dissolved N content and increasing moisture which negatively regulate the abundance of AOB and nirK-harboring genes to reduce N₂O emissions indirectly in rainfed maize fields on the Loess Plateau of China.

Planting density is a major limiting factor for maize yield, and breeding for density tolerance breeding has become an urgent issue.  The leaf structure of the maize ear leaf is the main factor that restricts planting density and yield composition.  In this study, a natural population of 201 maize inbred lines was used for genome-wide association analysis, which identified nine SNPs on chromosomes 2, 5, 8, 9, and 10 that were significantly associated with ear leaf type structure.  Further verification through qRT-PCR confirmed the association of five candidate genes with these SNPs, with the Zm00001d008651 gene showing significant differential expression in compact and flat maize inbred lines.  Enrichment analysis using the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) suggested that this gene is involved in the glycolysis process.  The analysis of the basic properties of this gene revealed that it encodes a stable, basic protein consisting of 593 amino acids with some hydrophobic ability.  The promoter region contains stress and hormone (ABA) related elements.  The mutant of this gene increased the uppermost ear leaf angle (eLA) and the first leaf below the uppermost ear (bLA) by 4.96° and 0.97° compared with normal inbred lines.  Overall, this research sheds light on the regulatory mechanism of ear and leaf structure that influence density tolerance and provides solid foundational work for the development of new varieties.

To popularize the soybean and corn strip intercropping technology in Western Yunnan, the key points of soybean and corn strip intercropping technology were introduced from the aspects of preparation before sowing, key points of sowing technology, field water and fertilizer management, crop control and topple prevention, field weeding, disease and pest control, harvest and storage. Before sowing should choose the convenient transportation, gentle terrain, conducive to irrigation of fertile soil, select a good weather for ploughing and loosening, deep ploughing 20-40 cm is appropriate; varieties with similar maturity and more synchronized growth and development are selected for planting. Sowing should be carried out in the season when the soil moisture and temperature are suitable, such as on-demand sowing and drill sowing. According to the characteristics of soybean and corn varieties, reasonable planting patterns are adopted, including 2-row corn and 2-row soybean, 2-row corn and 3-row soybean, and 2-row corn and 4-row soybean. In field water and fertilizer management, nitrogen fertilizer is the main fertilizer and phosphate fertilizer is the auxiliary fertilizer. Chemical control method is adopted to control the growth of corn and soybean. Field weeding management is carried out by chemical weeding and artificial weeding. In view of common root rot, corn borer, cotton bollworm, red fire ant and other diseases and pests of soybean and corn, comprehensive control measures such as physical control, biological pesticide control and ecological regulation are adopted. Adopt artificial or mechanical harvesting, timely harvest soybeans and corn, and timely drying, threshing, when the seed water content is less than 13%, packaging storage. This paper provides a reference for the further popularization of soybean and corn strip intercropping technology in the study area and related areas.

Based on the practice of strip intercropping of soybeans and corn in Hanzhong, Shaanxi Province, the soybean and corn strip intercropping technology from the aspects of pre-sowing preparation, sowing, field management, pest and disease control and so on were summarized and analyzed. In terms of preparation before sowing, corn varieties with strong resistance to dense planting, disease resistance, lodging and compact or semi-compact, and soybean varieties with strong shade resistance and lodging resistance are preferred. Sterilization of seeds such as coating, seed mixing or seed soaking. In terms of seeding, apply sufficient high quality decomposed farm fertilizer, combined with the application of compound fertilizer, according to the actual situation, in accordance with 3:2 or 4:2 model seeding, to ensure the seeding density. In terms of field management, closed weeding and post-seedling weeding are used to remove weeds. When the plants grew too well and the planting density is too high, plant growth regulator is applied to control the growth of the plants. In terms of pest control, the use of mechanical equipment for deep ploughing, turning the soil, or the use of insecticidal lamps in the adult insect occurrence period can effectively lure and kill pests, and select appropriate chemical agents for control according to the types of pests and diseases. In terms of harvesting, it should be harvest at the approprite in time and dry for storage. This paper provides references for optimizing planting layout and improving soybean and corn production performance in relevant areas.

Parental selection and breeding process of corn variety Bole 001 was introduced, and its cultivation and seed production techniques based on its planting characteristics in the Huang Huai Hai region were summarized. This variety is a high yield and stable corn variety with good comprehensive resistance, selected from dx35 as the female parent and L528A as the male parent. It was approved in 2023 with approval number National Approval Corn 20232124. This variety has the characteristics of good growth, excellent quality, good comprehensive resistance, and high yield. The key cultivation techniques include selecting suitable sowing areas; in the Huang Huai Hai region, the sowing is usually from June 5th to 15th; the planting density is more suitable between 67 500 and 70 500 plants/hm²; scientific fertilization and irrigation to ensure normal plant growth; combining soil sealing with stem and leaf spraying to prevent and control weeds in the field; comprehensive prevention and control of diseases and pests such as fall armyworm and rust on grasslands; harvest the seeds promptly when the milk line disappears and the unique luster appears. The key points of seed production techniques include the selection of seed production areas, reasonable sowing time and planting density, strengthened field management, timely removal of impurities and males, and harvesting, threshing. This article provides a reference for promoting the planting of this variety.

In response to the abnormal growth phenomena in corn planting in Funan County, Anhui Province, field investigations and analyses were conducted on some experimental sites in the study area to investigate the abnormal phenomena such as hollow stalks, bald tips, flower grains, and missing grains during the growth process of corn. The investigation found that abnormal climate, unreasonable sowing date selection, excessive planting density, and poor field management are the main reasons for the abnormal growth phenomena of corn. Therefore, measures have been proposed to reduce the incidence of abnormal growth phenomena, such as selecting a suitable broadcasting date, planting reasonably, strengthening fertilizer and water management, comprehensive prevention and control of diseases and pests, implementing a combination of manual assisted pollination and small scale unmanned aerial vehicle assisted powder dispersal, and timely late harvesting. This article provides a reference for improving the yield and overall benefits of corn cultivation.