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.

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.

The strip intercropping model of soybean and corn can fully utilize the edge row advantage and reasonably coordinate the needs of soybean and corn plants for light, fertilizer, and water. The practice of strip intercropping of soybean and corn in Northern Anhui Province was combined, and its high yield cultivation techniques and promotion effects were summarized. High yield cultivation techniques include selecting suitable soybean and corn varieties; reduce plant spacing, ensure density, and choosing soybean corn planting model of 4:2 or 6:4; adopt fungicides, insecticides, etc. for seed coating treatment, and adhere to the “four suitable” sowing methods of suitable period, suitable soil moisture, suitable depth, and suitable formula; applying sufficient basal fertilizer and applying topdressing at the appropriate time; timely check and supplement seedlings, adopting the weed control method of “closed weeding+spraying on stems and leaves after seedlings”, and paying attention to isolation measures; adopting integrated agricultural, physical, biological, and chemical control techniques for disease and pest prevention and control; timely chemical control to prevent plant lodging; after soybeans and corn mature, appropriate machinery is used for harvesting. The research area was promoted the applied this model from 2022 to 2024, achieving the goal of “basically no reduction in corn production and one additional season of beans”. This article provides a reference for promoting the strip intercropping model of soybean and corn in Northern Anhui Province and related areas.

In order to clarify and grasp the meteorological conditions and risk level forecasting technology for the occurrence and development of spring maize leaf spot disease in Tuquan County, a coupled analysis was conducted using the meteorological conditions of air temperature, relative temperature, precipitation, and 2-minute wind speed in Tuquan County over the past 10 years (2014-2023) and agricultural production data such as the time, degree, and affected area of spring maize leaf spot disease occurrence in Tuquan County over the past 10 years (2014-2023) to establish a prediction model for maize leaf spot disease occurrence. The analysis showed that the overall changes in four meteorological elements in each township of Tuquan County from May to September 2014-2023 tended to be consistent; Since 2019, there had been an increase in the proportion of the area, which had remained at around 10%. Utilizing four meteorological factors to establish meteorological indicators for the occurrence and development of maize leaf spot disease, it is possible to predict the occurrence area of spring maize leaf spot disease through a predictive model based on the statistical values of perennial meteorological factors and the forecast conclusions of meteorological factors for the next year, providing a scientific prevention basis for agricultural production.

【Objective】In terms of the issues of yield instability and quality deterioration caused by improper water and fertilizer application, the effects of reduced irrigation combined with organic and inorganic nitrogen fertilization on the yield and quality of silage maize in arid irrigated regions of Northwest China were investigated, so as to identify optimal water and fertilizer management practices for achieving high yield and superior quality in silage maize cultivation in the irrigated areas. 【Method】 From 2021 to 2022, a field experiment based on two-factor split-plot design was carried out at the Oasis Agricultural Experimental Base of Gansu Agricultural University. The main factor was two irrigation levels, respectively, including I1 conventional irrigation reduction 20 % irrigation was 324 mm, and I2 conventional irrigation is 405 mm, and drip irrigation was used. The sub-factor included five different fertilization regimes: F1, 100% chemical nitrogen fertilizer; F2, 75% chemical nitrogen fertilizer+25% organic fertilizer; F3, 50% chemical nitrogen fertilizer+50% organic fertilizer; F4, 25% chemical nitrogen fertilizer+75% organic fertilizer; and F5, 100% organic fertilizer. The effects of different water and fertilizer management practices on the yield, grain quality, and stalk quality of silage maize were analyzed, and the comprehensive evaluation of the yield and quality of silage maize was performed using factor analysis.【Result】Reducing irrigation alone led to a decrease in the yield and quality of silage maize. However, the combined application of organic-inorganic nitrogen fertilizers helped to enhance the potential for simultaneously improving both yield and quality under reduced irrigation conditions. Notably, the combination of reduced 20% irrigation with 75% chemical nitrogen fertilizer+25% organic fertilizer (I1F2) demonstrated significant advantages. The I1F2 treatment significantly increased fresh and hay yields of silage maize, with fresh and dry grass yields improving by 9.9% and 12.7% over conventional irrigation combined with 100% chemical nitrogen fertilization (the control treatment, I2F1), respectively. Meantime, the I1F2 treatment was able to maintain a relatively high grain and stover quality of silage maize. Compared with I2F1, the I1F2 treatment increased protein and fat contents of grain by 17.4% and 20.5%, and increased essential amino acids content too, with phenylalanine, valine, leucine, isoleucine, tryptophan, threonine, lysine, and methionine rose by 17.4%, 13.9%, 19.4%, 17.9%, 23.1%, 30.0%, 44.5%, and 22.0%, respectively. The I1F2 treatment increased crude protein, crude fat, and soluble sugar contents in the stover by 13.9%, 19.1%, and 15.6% over I2F1, respectively, while decreasing neutral detergent fiber content by 13.5%, thereby improving relative feed value by 14.0%. Factor analysis also revealed that the I1F2 treatment had the highest composite applicability index, which was beneficial for increasing both the yield and quality of silage maize.【Conclusion】The combination of 20% reduced irrigation with 75% chemical nitrogen fertilizer+25% organic nitrogen fertilizer was the optimal water and nitrogen management practice for simultaneously enhancing both the yield and quality of silage maize in the Northwest irrigation areas.

【Objective】 The effects of different nitrogen forms on filling characteristics, grain quality and yield of summer maize were studied, so as to provide the scientific basis for selecting suitable nitrogen fertilizer types and improving the yield and grain quality of summer maize. 【Method】 The experiment was conducted in Taian, Shandong Province from 2022 to 2023. Denghai 605 (DH605) was selected as the experimental material, with a nitrogen application rate of 210 kg N·hm^-2. The experiment included five treatments: amide nitrogen (Urea, UREA), nitrate nitrogen (Calcium nitrate, NN), ammonium nitrogen (Ammonium chloride, AN), co-application of nitrate and ammonium nitrogen (1:1, HH), and urea ammonium nitrate solution with a blend of amide nitrogen, nitrate nitrogen, and ammonium nitrogen (2:1:1, UAN). The effects of different nitrogen forms on the yield and quality of summer maize were investigated by determining the grain filling characteristics, grain quality characteristics and grain capacity of summer maize. 【Result】Compared with the conventional application of amide nitrogen in UREA, both the maize yield and grain quality under NN decreased. The maize yield under AN increased, but the grain quality decreased. HH significantly increased maize yield without affecting grain quality. UAN significantly increased maize yield and improved grain quality. Over the two years, the highest maize yield achieved with the co-application of the three nitrogen forms, significantly increasing by 13.7% to 16.3% compared with UREA. The Next the highest maize yield were from AN and HH, which significantly increased maize yield by 5.2% to 6.8% and 7.3% to 10.6%, respectively, compared with UREA. The maize yield under NN decreased by 5.4% to 5.8% compared with UREA. Compared with UREA, the growth amount at the maximum filling rate (W_max) under UAN was enhanced by 6.3% to 9.7%, and the active filling period (D) was extended by 7.7% to 10.9%. Both AN and HH increased W_max and prolonged D, thereby promoting the accumulation of grain weight and increasing yield. The W_max, D, grain filling rate, and dehydration rate of NN were significantly lower than those in the other treatments. The crude protein content was lower with NN and AN, decreasing by 20.6% to 22.0% and 15.2% to 17.4% than that under UREA, respectively. The rude fat content with NN was significantly higher than that of other treatments, increasing by 23.6% to 30.9% than that under UREA. Compared with UREA, UAN improved grain quality, with total starch and amylopectin content increasing by 4.9% to 5.2% and 11.7% to 14.4%, respectively, compared with UREA, and the ratio of amylopectin to amylose increased by 31.0% to 39.1%. The amylose content decreased by 14.1% to 16.8%. The crude protein content of UAN increased by 11.7% to 24.1%. The grain bulk weight under UAN was significantly higher than that under other treatments. 【Conclusion】Compared with the conventional application of amide nitrogen, the treatment with nitrate nitrogen inhibited grain filling, reduced grain weight, and decreased yield. In contrast, ammonium nitrogen or the co-application of multiple nitrogen forms enhanced the grain filling process, increased grain weight, and thereby improved yield. Furthermore, compared with the application of a single nitrogen form, the co-application of three nitrogen forms could achieve a synergistic improvement in both yield and grain quality.

Maize root system plays a crucial role in the development of the aboveground plant and determines the yield through the uptake of water and nutrients in the field.  However, the genetic architecture of the maize root system is largely unknown mainly due to its complexity and the interactions between genotype and environment.  Using a high-throughput semi-automatic hydroponic platform with stable conditions, we comprehensively characterized the root system in a core population of 518 diverse inbred lines of maize.  Population structure analysis revealed that the panel has stratification and a linkage disequilibrium decay distance of less than 50 kb.  Based on genotyping with the high-density 600 K SNPs, we conducted a genome wide association analysis (GWAS) and identified nine SNPs and seven candidate genes significantly associated with 24 traits.  One candidate gene, GRMZM2G400533, is located at the upstream 5 kb region from the leading SNP (AX-91771718) and was significantly associated with primary root length and preferentially expressed in the primary root and crown root.  Expression of GRMZM2G400533 increased as the primary root developed but was negatively correlated with primary root elongation.  An analysis of candidate gene GRMZM2G400533 identified three functional variants and eight allelic haplotypes.  This study will broaden our understanding of maize root development and provide a theoretical basis for maize improvement through optimization of the root system.

【Objective】To clarify the molecular characteristics and the effectiveness of target traits of transgenic maize LD05 with composite insect and herbicide resistance, and to provide data basis, technical support and product reserve for industrial application.【Method】Using biological information analysis, we designed and modified the proprietary insect-resistant fusion gene m2cryAb-vip3A, and selected BC₄F₃, BC₄F₄ and BC₄F₅ generations of the newly created transgenic hybrid insect-resistant and herbicide-tolerant maize LD05 to carry out experimental research. Specific PCR and Southern blot were used to analyze the stability of genomic integration. qRT-PCR and ELISA were used to analyze the expression stability. The resistance to target pests was evaluated by bioassay and field trials, and the herbicide tolerance was tested by field spraying of glufosinate. 【Result】A new insect-resistant fusion gene m2cryAb-vip3A with independent property right was discovered and designed, and a multivalent insect-resistant and herbicide resistant maize transformant LD05 was created. The exogenous T-DNA was integrated into the maize genome in the form of a single copy. The qRT-PCR results indicated that m2cryAb-vip3A and bar were both expressed in various tissues and organs across three generations, and the variation trend of expression quantities was largely consistent. Specifically, the expression level of m2cryAb-vip3A was the highest in the leaves at the seedling stage of the three consecutive generations, with an average expression quantity of 36.73, while the expression level was the lowest in the cob at the mature stage, with an average of merely 0.91. The expression pattern of bar was similar to that of m2cryAb-vip3A, with the highest expression level in the leaves at the seedling stage, averaging 7.35, and the expression level decreased after the jointing stage. The ELISA results demonstrated that M2CryAb-VIP3A could stably accumulate in different organs and at different periods in the three generations, and the protein accumulation amounts in different generations were similar. Among them, the accumulation amount was the highest in the leaves at the seedling stage of different generations, all exceeding 19.67 μg·g^-1 fresh weight. The expression of the targeted protein at a relatively high level could be detected in different tissues of the PAT transgenic plants of three consecutive generations, and there was no significant difference in the expression quantity between different generations. Among them, the expression level was the highest in the leaves at the seedling stage of different generations, with an average content of 16.61 μg·g^-1 fresh weight, while the accumulation amount was the lowest in the roots at the mature stage, with an average content of 0.30 μg·g^-1 fresh weight. The bioassay result showed that the corrected mortality of Ostrinia furnacalis, Spodoptera fragiperda and Mythimna separata reached 100% after feeding on V5 maize leaf tissue of LD05 for 96 h, which was a high resistance level. The results of field trials showed that LD05 transformants had high resistance to Ostrinia furnacalis at V5 stage and silking stage, to Mythimna separata at V5 stage, and to Helicoverpa armigera at silking stage. The results of glufosinate tolerance test showed that transgenic maize LD05 could tolerate 4-fold glufosinate. Agronomic character investigation showed that there was no difference between transgenic maize LD05 and control maize Zheng 58.【Conclusion】A novel insect-resistant fusion gene m2cryAb-vip3A with independent property rights was developed, and a transgenic hybrid insect-resistant and herbicide-tolerant maize LD05 was created with clear molecular characteristics, genetic stability and outstanding functional traits.

【Objective】Increasing planting density is a key agronomic strategy to enhance maize yield; however, excessive density may result in an imbalanced population structure, reduced utilization efficiency of limited resources (e.g., light), and suppressed yield potential. Gene editing can optimize canopy architecture through targeted improvement of maize plant type, thereby enhancing adaptability to high-density planting and boosting yield. Elucidating the effects of plant type improvement on root-shoot characteristics, grain yield, and density response in spring maize, as well as the underlying mechanisms, will provide theoretical and technical foundations for optimizing plant type and achieving high-yield dense planting in spring maize.【Method】The field experiment was conducted at Gongzhuling farm in Jilin, China. In this study, two maize hybrids, includding Jingke 968 and the improved plant types Jingke Y968, were grown with 60 000 plants/hm² (D1), 75 000 plants/hm² (D2) and 90 000 plants/hm² (D3) in 2019 and 2020, respectively. The effects of two plant types of spring maize of the same genetic background on the root-canopy characteristics and yield of spring maize were studied.【Result】Under normal density conditions (D1), there were no significant differences in leaf area index (LAI), net photosynthetic rate (Pn), PAR utilization (PUE), dry matter accumulation and grain yield between the two different plant types spring maize cultivars. However, compared with Jingke 968, under D3 conditions, the improved plant type Jingke Y968 had a relatively high number of main roots (7.2%) and a relatively large weight of root dry matter (6.0%), which promoted the absorption of nutrients; furthermore, under D2 and D3 conditions, Jingke Y968 significantly improved the canopy structure of maize, so that the upper, middle and lower parts had relatively low leaf angles, higher leaf orientation and LAI, and the excellent canopy structure increased the Pn of mid-to-late ear leaves of (7.5% (D2) and 7.7% (D3)) and PUE (4.3% (D2) and 10.8% (D3)). The structural equation results showed that higher leaf direction values and LAI could positively and directly increase the accumulation of dry matter in the aboveground, thereby increasing grain yield (8.7% (D2) and 11.2% (D3)).【Conclusion】In summary, the improvement of plant type enabled Jingke Y968 to have higher main root number and larger root dry matter weight under high-density conditions, which was conducive to nutrient absorption in the underground part. Meanwhile, its leaves were more compact, Pn was significantly increased, PUE was effectively improved, and root-canopy characteristics were more reasonable, which promoted dry matter accumulation in the above-ground part. Thus, the relatively high grain yield could be obtained.

The aim of this study was to provide scientific guidance for the promotion and cultivation of new sweet-waxy maize varieties. In order to explore the effects of different planting densities on the yield and main agronomic traits, in this experiment, the sweet-waxy maize varieties ‘Guitiannuo 108’ and ‘Guitiannuo 189’ were used as experimental materials, and five density levels were set as 40000, 46667, 53333, 60000 and 66667 plants/hm², as well as two sowing dates in spring and autumn. The results showed that the yield per plant, ear length, ear diameter and stem diameter decreased with the increase of planting density; while the yield per unit area and cob tip bald length increased with the increase of planting density. Considering yield and economic benefits comprehensively, the reasonable planting density for ‘Guitiannuo 108’ and ‘Guitiannuo 189’ in Guangxi is 46667-53333 plants/hm².

This study aims to systematically summarize the application of maize live haploid technology in maize molecular breeding, with focus on exploring the selection methods, formation mechanisms, identification methods, doubling methods, and application in population improvement of maize live haploid high-frequency induction lines, providing reference and guidance for the large-scale application of live haploid breeding technology. This study used a literature review method to summarize the relevant research results and practical experience on maize haploid technology, and analyzed the advantages and disadvantages of various methods in practical applications. The research results indicated that maize live haploid technology played an important role in breeding excellent inbred lines and population improvement. Through high-frequency induction line breeding, a large number of excellent haploid plants had been successfully obtained; the identification and doubling methods effectively improved haploid formation and stability. The live haploid technology had shown significant doubling effects in population improvement, providing new ideas and methods for maize breeding. In summary, maize live haploid technology is an efficient and rapid breeding method with broad application prospects. In the process of corn breeding, combining live haploid technology can accelerate the pace of quality improvement and yield increase, providing strong support for the healthy development of the corn industry.

Based on the practice of belt shaped composite planting of soybean and corn,the advantages and key points of its planting technology were summarized and analyzed, the problems in the application of the technology were pointed, and specific application strategies were propoesd. The spatial layout of soybean corn strip intercropping is reasonable, which is conducive to improving land use efficiency, increasing crop yield, and improving the ecological environment. The key cultivation techniques of this model include planting model selection, variety selection, suitable sowing, reasonable fertilization, chemical weed control, chemical pest control, and mechanical harvesting. In terms of production, this model currently has issues such as differences in sowing and harvesting machinery, inconsistent occurrence of pests, diseases, and weeds, and inconsistent prevention and control agents; in this regard, it is proposed to strengthen cooperative research and development, accelerate the development of new specialized machinery, improve the adaptability of machinery, select corn varieties resistant to soybean herbicides, strengthen the development of new pesticides, and thereby pay attention to field management and assist in achieving double harvests in one field. This article provides a reference for further promoting the belt shaped composite planting technology of soybean and corn.

Summer corn Shangdan1967 was used as test material, 4 treatments were set up: no biochar (CK), biochar 10 t/hm² (T₁), biochar 20 t/hm² (T₂) and biochar 40 t/hm² (T₃). The effects of biochar on photosynthetic characteristics such as chlorophyll content (SPAD value), net photosynthetic rate; superoxide dismutase (SOD), peroxidase (POD) activity and other physiological characteristics,and yield were analyzed. The results showed that T₂ and T₃ treatments could increase SPAD value, net photosynthetic rate, and transpiration rate, and reduce intercellular CO₂ concentration, with statistically significant difference compared with CK (P<0.05). Biochar treatment could increase SOD and POD activities, and increased with the increase of biochar application amount, that was T₃>T₂>T₁>CK. The content of malondialdehyde (MDA) in ear leaves was decreased with the increase of biochar application, that was, CK>T₁>T₂>T₃. Biochar treatment increased the yield of summer corn, and the yield of T₁, T₂, and T₃ increased by 5.80%, 9.98%, and 16.88% compared with CK. In conclusion, the application of biochar can improve the photosynthetic performance of maize post-ear leaves, increase the antioxidant enzyme activity of ear leaves, delay the senescence of ear leaves, and thus increase corn yield, and the application rate of 40 t/hm² has the best yield increase effect.

The production practice of fresh corn was combined in the Ili River Valley region, Xinjiang, its high yield planting techniques and application prospects were summarized and analyzed. In terms of high yield cultivation techniques for fresh corn, including selecting high quality varieties with good adaptability and disease resistance; adjusting the sowing date and method based on local climate differences and crop varieties; fine soil preparation, using precise sowing techniques; reasonably plant closely according to the characteristics of different corn varieties, adopting spatial isolation, temporal isolation, or natural barrier isolation for planting isolation, fertilize and irrigate according to the needs of each growth stage of corn, and adopting ecological management, agricultural control, biological control, and physical induction control methods for green pest control; timely harvest and carry out preservation treatment. Fresh corn is widely used in the fields of agriculture, industry, and animal husbandry. Its high quality and efficient production is of great significance in ensuring food security, meeting market demand, increasing grow’ income, promoting agricultural modernization, and promoting industrial integration and development. This article provides a reference for high quality and efficient production of fresh corn in the Ili River Valley and related areas.

This study investigated the effects of combining controlled-release nitrogen (CRN) fertilizer on nitrogen absorption and utilization in spring maize, and to provide scientific evidence and technical guidance for optimizing fertilization strategies to achieve high yield and efficient nitrogen utilization in spring maize cultivation in eastern Sichuan. A field experiment was conducted to assess the changes in yield, nitrogen absorption, and nitrogen utilization under seven nitrogen management treatments. The treatments included no nitrogen application (CK), conventional nitrogen application (ON) and CRN fertilizer applied at 0% (NR0), 25% (NR25), 50% (NR50), 75% (NR75) and 100% (NR100) of the conventional nitrogen rate, with a 25% reduction in total nitrogen input in eastern Sichuan. The results showed that CRN fertilizer significantly enhanced both dry matter and nitrogen accumulation in maize. At the tasseling and silking stage, with the increase of the proportion of CRN fertilizer, the rates of dry matter and nitrogen accumulation initially promoted, then reduced. After the filling stage, a CRN proportion of ≥50% was most effective for both dry matter and nitrogen accumulation, with NR50 showing the highest values. CRN fertilizer also promoted the redistribution of nitrogen from vegetative organs to grains. However, as the proportion of CRN fertilizer increased, the contribution of nitrogen from vegetative organs to grains decreased. Furthermore, CRN fertilizer improved the yield factor composition and maize yield, with NR50 showing the most significant increase. Agronomic efficiency and partial factor productivity of CRN fertilizer were higher than those of conventional nitrogen application. NUE of NR50, NR75 and NR100 was greater than that of ON. In conclusion, a 25% reduction in total nitrogen application, combined with 50% CRN fertilizer and 50% urea, was the optimal fertilization strategy for improving nitrogen absorption, enhancing dry matter and nitrogen accumulation, and increasing both yield and nitrogen use efficiency in spring maize in eastern Sichuan.

To screen the excellent maize varieties suitable for planting in Lingbi County, Anhui province, 34 new corn varieties, such as Kangnongyu 8009, Zhongyu 303 and Siyougu No. 5, were used as experimental materials, growth period and disease resistance were recorded, and agronomic traits, such as plant height, yield and yield traits, such as 100 grain weight were measured and evaluated comprehensively. The results showed that the growth period of each variety was 99-105 days. In terms of resistance, stem rot and small spot of all varieties were grade 1, and some varieties were susceptible to rust and sheath blight. In terms of agronomic traits, plant height was 206.4-267.3 cm, ear position 67.2-103.4 cm, ear diameter 4.3-5.0 cm, row number of spike 12.4-17.6 rows, row number 29.0-36.1 grains, seed yield 88.0%-91.5%. In terms of yield and yield traits, the effective panicle was 67 500 panicles /hm², the 100 grain weight was 25.43-36.42 g, the number of grains per panicle was 378.96-603.94 grains, and the yield was 7 240.50-10 062.75 kg/hm². The 5 varieties of Longding 728, Pudan 12, Jiaxi 100, Weike 985 and Denghai 1875 had the best comprehensive performance and were suitable for planting in the study area and related areas.

Literature review combined with practice was used to analyze the advantages of promoting corn planting techniques, the practical problems encountered in the process were explored of promoting planting techniques, and optimization measures were proposed. The promotion of corn planting techniques is beneficial for improving corn yield, optimizing quality, and increasing farmers’ income; in the process of techniques promotion, there are mainly problems such as unsmooth promotion channels, lack of personalized services, and low acceptance of new technologies by farmers. Based on the existing practical problems, propose to improve the corn planting technology promotion service system, provide personalized technical services for corn planting, and enhance farmers’ awareness and understanding of new technologies and other agricultural technology promotion strategies. The promotion of corn planting techniques is of great significance for the sustainable development of corn planting industry. This article provides a reference for further promotion and application of corn planting techniques in relevant regions.

The corn industry in Huangshan City of Anhui Province had made some achievements in recent years, and the area and output had grown year by year. This article introduces the basic situation of the corn industry from 5 aspects: the natural conditions, the corn planting area and output of corn over the years, the corn planting area and output of corn in each district and county, the promotion of varieties and the promotion of technology. It analyzes the main problems in 5 aspects of natural conditions, planting level, scale level, socialized service level, and corn industry chain. Based on the above analysis, some strategies are put forward such as strengthening the construction of agricultural infrastructure, accelerating the introduction and promotion of new varieties，promoting green high-yield cultivation technology, cultivating social service organizations, strengthening the construction of regional public brands, and promoting the extension and supplement of industrial chain to provide a reference for the development of the corn industry in relevant regions.

To explore the effects of water-fertilizer integration technology on the characters and yield of close-planted corn, 4 treatments were set up in this experiment. Including high dense planting corn A with integrated water and fertilizer system for 4 times (T₁), high dense planting corn B with integrated water and fertilizer system for 4 times (T₂), high dense planting corn B with integrated water and fertilizer system for 4 times + chemical control at jointing stage for 1 time (T₃), and high dense planting corn B with integrated water and fertilizer system for 4 times without adding fertilizer + conventional fertilizer (CK). Temperature, agronomic traits such as plant height and green leaf rate, and economic characters such as number of grains per spike and weight of 100 grains were measured. The results showed that T₂ showed better agronomic traits, with higher plant height, ear position and leaf length and width. The green leaf rate, grain number per spike and unit yield of T₃ were significantly higher than those of other combinations, which were 93.25%, 565.8 grains per spike and 14 220 kg/hm², respectively. In conclusion, the application of water-fertilizer integration technology on close-planted corn can appropriately reduce fertilizer application, increase plant height, ear row number, row number and unit yield.

To promote the promotion and application of green prevention and control technology in the prevention and control of corn diseases and pests, the specific applications and prevention effects of agricultural prevention and control, physical prevention and control, biological prevention and control, and chemical prevention and control were studied by reviewing relevant literature and combining practice. The main measures for agricultural prevention and control include selecting corn varieties with strong adaptability, high-yield, and excellent quality; croping rotation with crops such as soybeans and wheat to reduce the occurrence of pests and diseases; utilizing the ecological complementarity between different crops, intercropping with crops such as potatoes and peanuts; reasonably controling the ratio of nitrogen, phosphorus, and potassium fertilizers, scientifically applying base and topdressing fertilizers to improve the stress resistance of corn; timely and moderate irrigation to maintain suitable soil moisture. Physical prevention and control mainly uses physical factors or mechanical equipment, such as insect-killing lamp and sticking traps, to attract and kill pests. Biological prevention and control mainly utilizes natural enemies and microbial agents for control. Chemical control is mainly applied in situations where diseases and pests are severe or biological control methods cannot effectively respond, through scientific and precise application of drugs to effectively control pests and diseases. The comprehensive application of green prevention and control technology can reduce the incidence of corn diseases and pests, improve yield and quality, it is an effective way to achieve sustainable corn production. This article provides references for achieving high-quality, efficient, and eco-friendly corn and other crops production.

Maize (Zea mays L.) is a monoecious grass species with separate male and female inflorescences which form the tassel and ear, respectively.  The mature ear inflorescences usually bear hundreds of grains, thus directly influence maize grain production and yield.  Here, we isolated a recessive maize mutant, tasselseed2016 (ts2016), which exhibits pleiotropic inflorescence defects and a reduction in grain yield.  These defects include loss of determinacy and identity in meristems and floral organs, as well as a lack of the lower floret abortion in maize ear, and the smaller grain size.  Using map-based cloning and allelic test, we identified and confirmed a microRNA gene MIR172e as the target gene controlling these related traits.  Furthermore, our evidence uncovered a new potential miR172e/ETHYLENE RESPONSIVE ELEMENT BINDING197 (EREB197) regulatory module which controls the abortion of lower floret in maize ear. Transcriptome analysis revealed that the mutation of MIR172e represses multiple biological processes, particularly the flower development and hormone-related pathways in maize ear.  Additionally, we found the mutation in the DNA sequence of MIR172e affects in RNA transcription, resulting in elongation blockage at the mutant site.  Our results reveal the function and molecular mechanism of MIR172e in maize inflorescences and grain yield, and this study deepens our knowledge of maize inflorescence development.

Foodstuff maize is an important part of the modern maize industry in Linzhi City, and its production and application are extremely wide. In order to find out the high yield and high efficiency planting methods, we used three sowing densities (6×10⁴, 9×10⁴ and 12×10⁴ plants/hm²), and set up three harvest times (1/3 milk-line, 2/3 milk-line and milk-line disappeared stages) under the sowing density of 9×10⁴ plants/ hm², to compare and analyze grain yield, bio-yield and other yield traits of three different maturity maize hybrids (very early maturity, early maturity and medium maturity). The results showed that the fertility period of maize of different maturity was extended when planted in Linzhi City. The yield potential of medium-maturing variety was higher than that of very early and early-maturing varieties. Because of the limited soil fertility in Linzhi City, the planting density should not be too high, and should be controlled within 6×10⁴ plants/hm² in mid-low yielding lands, and should not exceed 9×10⁴ plants/hm² in high yielding field. Due to the local temperature influence, the grain filling rate was slow. The grain maize should be harvested at the stage of the milk-line disappearance, while the best harvesting time for silage maize was at the stage of 1/3 milk-line. In Linzhi City habitat, variety maturity had the greatest effect on the yield of foodstuff maize, sowing density should not be too high, and harvesting time differed according to specific uses.