This study aims to assess the salt tolerance of perennial rice varieties (lines) ‘PR23’, ‘PR24’, ‘PR25’, ‘PR26’, ‘PR101’, ‘PR107’, and ‘PR109’, and to screen out elite salt-tolerant germplasm. The experiment employed NaCl solutions at concentrations of 0, 50, 100, 150, and 200 mmol/L to conduct salinity stress treatments on perennial rice varieties (lines) and the parent ‘RD23’. The vitality parameters (seedling height, root length, fresh weight, dry weight, etc.) and salt tolerance coefficients of varieties were determined under different NaCl concentrations. Principal component analysis (PCA) and the membership function method were used to comprehensively evaluate the salt tolerance performance of the varieties (lines). The results showed that: (1) significant differences in salt damage levels among varieties (lines) were observed when NaCl concentration reached 150 mmol/L. Among all the phenotypic traits associated with salt stress, except for root length, all other traits under the 150 mmol/L NaCl treatment showed significant differences from the control group (P < 0.05), establishing this concentration as the optimal level for screening salt tolerance in perennial rice during the seedling stage. (2) PCA of the relative values of salt tolerance traits under the 150 mmol/L NaCl treatment generated membership function values. Combining with the principal component variance contribution rate weight, the comprehensive evaluation D value was obtained, showing that ‘Yun Da 107 (PR107) ’exhibited the strongest comprehensive salt tolerance ability at the seedling stage, while ‘PR101’ showed the weakest salt tolerance capacity. Other varieties (lines) had intermediate salt tolerance levels. This study provides high-quality germplasm resources for rice salt tolerance breeding and lays the foundation for future improvements in rice salt tolerance. This study not only identifies elite salt-tolerant rice germplasm resources through phenotypic and genotypic assessments, laying a foundation for genetic improvement of rice salt tolerance, but also provides critical data support for further research on salinity stress tolerance mechanisms.
The distribution characteristics of trace elements in wheat were analyzed in order to provide scientific basis for scientific regulation of trace element content in wheat and cultivation of new wheat varieties. The distribution characteristics of trace elements, including iron ( Fe ), manganese ( Mn ), copper ( Cu ) and zinc ( Zn ) in different organs of wheat at maturity stage were analyzed by using wheat varieties popularized in large area in northern Henan as experimental materials. The content of Fe in wheat plants ranged from 42.31 to 80.66 mg/kg, the content of Mn ranged from 212.11 to 604.89 mg/kg, the content of Cu ranged from 12.31 to 16.35 mg/kg, and the content of Zn ranged from 48.77 to 87.08 mg/kg. The variation coefficients of Fe, Mn, Cu, Zn contents in roots, stems, leaves, glume and grains of wheat plants showed different rules. The order of Mn enrichment ability of different organs of wheat was leaf > root > grain > stem > glume, and the order of Cu and Zn enrichment ability was root > grain > leaf > stem > glume. The order of Fe, Cu and Zn transport capacity of wheat organs was grain > leaf > stem > glume, and the order of Mn transport capacity was leaf > grain > stem > glume. The order of enrichment ability of trace elements in wheat roots, stems, glume and grains was Zn > Cu > Mn > Fe, and the order of enrichment ability of trace elements in leaves was Mn > Zn > Cu > Fe. The transport capacity of trace elements Cu, Mn, Zn in stems, leaves and glume of wheat was greater than that of Fe, and the order of transport capacity of trace elements in grains was Zn > Cu > Fe > Mn. The results of correlation analysis showed that there was a significant interaction between trace elements. The distribution of trace elements in wheat plants in northern Henan showed a vertical distribution pattern. The enrichment ability of trace elements in roots, leaves and grains was strong, and the transport ability of trace elements in leaves and grains was strong.
This study aimed to identify suitable maize varieties for maize-soybean strip intercropping promotion in the hilly areas of Chongqing. Using 24 maize varieties and the soybean variety ‘Yudou 11’ as experimental materials, with a 4:2 row ratio configuration of soybean to maize, the agronomic traits, yield and component traits of different maize varieties were compared, as well as the yield and component traits of soybeans under maize-soybean strip composite planting. The results revealed significant variations in maize plant characteristics under the intercropping system, with coefficient of variation (CV) reaching 74.13% for barren plants and over 100% for lodging rate, indicating substantial genotypic differences. Grain yield showed significant positive correlations with ear diameter, kernels per row, 100-kernel weight, bulk density and kernel length (P<0.05), while demonstrating highly significant negative correlations with barren plant rate and a significant negative correlations with ear tip barrenness. Path analysis showed the direct path coefficient for grain yield in ear length (0.484), kernel rows per ear (0.272), and 100-kernel weight (0.334) had direct positive effects on grain yield. The yield of 'Xianyu 1171', 'Keda 202', 'Jindan 9', 'Sanxiayu 23' and 'Jingyu 719' in all aspects of the performance was better, which were 10790.65 kg/hm2, 10034.5 kg/hm2, 9780.23 kg/hm2, 9595.40 kg/hm2 and 9442.72 kg/hm2, respectively, with an increase of 45.31%, 35.13%, 31.7%, 28.73% and 26.54%, respectively compared to the control. Significant differences were observed in the yield and yield components of 'Yudou 11' when intercropped with different maize varieties. Except for 'Jingyu 719' (618.84 kg/hm2), soybean yields intercropped with other maize varieties showed reductions compared to the control. Among them, the reductions in soybean yield were relatively lower when intercropped with 'Xida 889', 'Xianyu 1171', 'Yudan 32', 'Aiheyu 058', 'Rongyufengzan', and 'Sanxiayu 23', with reductions of 2.86%, 6.41%, 7.09%, 7.15%, 8.54%, and 8.7%, respectively. Comprehensive analysis identified 'Xianyu 1171', 'Sanxiayu 23', and 'Jingyu 719' as optimal varieties, which demonstrated superior agronomic performance, higher maize yields, and minimal negative impacts on soybean productivity, and making them suitable for maize-soybean strip intercropping systems in Chongqing's hilly regions.
To investigate the influence of different plastic film mulching on sweet potato growth, three cultivars, ‘Yanshu 25’, ‘Hami’, and ‘Long 9’, were used as test subjects. The effects of black film mulching, white film mulching, and black and white film mulching on the main agronomic traits and yield of sweet potatoes were studied. The results demonstrated that plastic film mulching improved all measured agronomic traits and yield to varying degrees, with the most significant enhancements observed under black-white composite film and black film mulching. Compared to the non-mulching control (P<0.05), black-white film mulching treatment increased the yield of ‘Yanshu 25’ and ‘Hami’ by approximately 20%. Across the three cultivars, the yield improvement followed this order: black-white film > black film > white film > no mulching. Correlation analysis between agronomic traits, quality, and yield revealed that branch number per plant, marketable rate, and dry matter content showed significant correlations with aboveground fresh weight, while yield was significantly correlated with underground fresh weight. The response to different mulching treatments varied among sweet potato cultivars, which may be attributed to intrinsic crop characteristics and their adaptability to environmental conditions. This study shows that black and white plastic film mulching significantly improves the yield and quality of sweet potato, and has important application prospects.
This research focused on optimizing the parental row ratio and developing suitable field cultivation techniques for hybrid rapeseed production, aiming to provide a theoretical foundation for advancing hybrid breeding technology. The experiment utilized a sterile line (716A) × restorer line (13R) hybrid combination in a two-factor split-plot design, to test six different parental row ratios along with two bolting-stage treatments (topping and non-topping).The results demonstrated that different parental row ratios significantly influenced both agronomic traits and seed production yield in rapeseed. Under single-row paternal line arrangements, seed yields followed the order: T12M1 > T13M1 > T14M1, whereas dual-row paternal configurations exhibited a different hierarchy: T26M1 > T24M1 > T28M1. The bolting-stage topping treatment significantly influenced rapeseed agronomic traits. Compared with the non-topped plants, topped specimens showed average reductions of 9.01% in plant height, 60.03% in effective branching height, 31.19% in primary branch number, and 25.02% in silique number on primary branches. Conversely, secondary branches demonstrated average increases of 28.08% in branch number and 50.52% in silique production. However, the total silique number per plant decreased by 7.03% on average, likely because the increased silique production on secondary branches failed to compensate for the reduction in primary branches. This was accompanied by an average decrease of 6.06% in seeds per silique, ultimately resulting in a 4.98% average reduction in hybrid seed production yield. Based on comprehensive evaluation of all indicators, the T26M1 treatment achieved the highest yield. In conclusion, under the experimental conditions set in this study, when the parent row ratio was configured at 2:6 and no bolting removal was applied to the female parent during the bud and bolting stage, both the seed production yield and economic benefits of rapeseed reached their optimal levels.
Seedling cultivation based on ebb-and-flow irrigation mode is a new type technology with water-saving, fertilizer-reducing and efficient-improving characteristics, in which ebb-and-flow parameters play a key role. To clarify the appropriate ebb-and-flow parameters in tobacco seedling cultivation, this study conducted a uniform design experiment on irrigation interval frequency, nutrient concentration, and liquid supply height. Both main effect analysis and comprehensive contribution rate analysis showed that irrigation interval frequency had the greatest impact, followed by nutrient concentration and liquid supply height. The interaction effects were significantly greater than the single factor main effect. The ridge regression model was optimized with irrigation interval frequency of 30.50 h/time, nutrient concentration of 153.94 mg/L, and liquid supply height of 3.84 cm, which could stably obtain the best seedling. Furthermore, the ebb-and-flow parameter for optimization management plan were irrigation interval frequency of 28.8-30.5 h/time, nutrient concentration of 153-154 mg/L, and liquid supply height of 3.8-3.9 cm, respectively.
To explore the law of water and salt transportation under different improvement modes of saline-alkali land in the Yellow River Delta, this study innovatively adopted a combination of continuous dynamic monitoring ( June-November 2024 ) and multi-factor ( soil-groundwater-drain ) comprehensive analysis. Taking Kenli District of Dongying City as the research area, the response mechanism of water and soil environment in the process of saline-alkali land improvement was systematically studied through field fixed-point sampling. The results showed as follows. (1) Under the condition of subsurface pipe drainage, the soil total salt content in the rice-improved area decreased by 82.81%-91.73% at the end of the growth period, which was significantly higher than that in the rain-fed area (71.79% -81.54%). (2) Following the conversion to rice cultivation, the soil pH increased, and salt leaching led to a pH increase of 6.55%-13.10%, showing a typical 'desalination and alkalization' feature; Notably, except for HCO3-, there was a significant correlation observed between other ion indicators, total salinity and soil pH. (3) The total salt content of groundwater was driven by irrigation-precipitation coupling, showing a trend of increasing first and then decreasing. The buried depth from July to September was generally <1.2 m, and the water quality from August to November (total salt content >2g/L) exceeded the standard of farmland irrigation and should not be directly used for farmland irrigation. The results of this study can provide some theoretical and technical support for the regulation and control of soil salinization in the Yellow River Delta.
To explore the changes of microbial community structure in tobacco-planting soil after application of silicon-rich soil improvement fertilizer and the effects of functional flora on soil nutrients and yield and quality of flue-cured tobacco, the root soil of flue-cured tobacco variety ‘K326’ was used as the experimental material, and the silicon fertilizer of 75 kg/hm2 was supplemented under the condition of conventional application of organic fertilizer as the base fertilizer, and the local conventional fertilization scheme was used as the control. By recording the agronomic traits of tobacco plants in the field and the economic traits of tobacco leaves, the Illumina Mi Seq high-throughput sequencing was used to measure the fungi, bacteria genes and conventional physical and chemical properties of tobacco root soil in the two treatments. The results showed that the soil available phosphorus, organic matter content and pH, agronomic traits of tobacco plants and economic traits of flue-cured tobacco leaves treated with silicon-rich soil improvement fertilizer were significantly higher than those of the control treatment. There was no significant difference in the classification level of fungi and bacteria between the two treatments. Ascomycota, Basidiomycota, Actinobacteriota, Proteobacteria and Firmicutes were the main fungi and bacteria. At the genus level, Fusarium, Saitozyma, Chaetomium and Sphingomonas were the dominant genera in the silicon-rich soil improvement fertilizer treatment, and unclassified_k__Fungi was the unique genus in this treatment. Among them, Chaetomium, Saitozyma, unclassified_c__Sordariomycetes, Bradyrhizobium and norank_f_JG30-KF-AS9 showed a significant positive correlation with soil nutrients. Effective nitrogen content and pH were greatly affected by fungal microorganisms, and organic matter was greatly affected by bacterial microorganisms. The richness of fungal species in the root soil of tobacco plants treated with silicon-rich soil improvement fertilizer was lower than that of the control treatment, and saprotroph fungi were the main fungal types. The bacterial species richness and KO number were significantly higher than those of the control treatment. The results showed that the application of silicon-rich soil improved fertilizer could not only increase the yield and output value of flue-cured tobacco, but also supplement soil fertility and regulate soil acidity, and slow down the acidification degree of sandy soil. In this study, the effects of soil improvement fertilizer on acidified sandy soil in high altitude area were compared from the perspective of soil microbial structure and function prediction, in order to provide scientific reference for the scientific and reasonable application of agricultural production fertilizer and the production of microbial fertilizer in similar areas.
The objective of this study is to explore the agro meteorological conditions and suitable climatic zoning of rice cultivation under the complex mountainous terrain of Zhijin County. The correlation between rice meteorological yield and meteorological factors was analyzed by mathematical statistics, the key meteorological factors affecting the growth and development of rice were screened out, a localized rice meteorological yield forecast model was established, and the forecast results were tested. At the same time, according to the meteorological data and disaster weather data, combined with various disaster indicators, the zoning map of rice planting suitability in Zhijin County was comprehensively drawn. The result showed that eight meteorological factors, including average temperature and sunshine hours in late May, precipitation in late June, precipitation and sunshine hours in mid-July, average temperature and precipitation in early August, and precipitation in early September, had the best correlation with the growth and development of rice in Zhijin County. The average forecast accuracy of the established localized forecasting model is more than 90%, and the forecast results are credible, which is suitable for localized yield forecasting. The zoning map of rice climate suitability showed that the climate of southern and western townships in the central part of Zhijin County was the most suitable for rice planting, while the suitability of rice planting in the northern and eastern towns was poor. The prediction model established in this study has good prediction ability for rice yield in Zhijin County. The generated climate suitability zoning map clearly reveals regional differences, which can provide an intuitive decision-making basis for optimizing local rice planting layout, avoiding meteorological disaster risk and improving yield level.
Agricultural carbon reduction and sink increase is a key strategy to cope with climate change. Straw returning is one of the most effective methods for sequestering carbon in soil. However, the conventional straw returning methods currently used in China are often associated with the occurrence of soil-borne diseases and pests, and their carbon sequestration performance lacks stability. Therefore, this study innovatively proposed the synergistic returning mode of Traditional Chinese Medicinal Residues (TCMR) and straw, aiming to clarify its synergistic mechanism, which using TCMR to effectively inhibit soil-borne pests and diseases caused by straw returning, and synergistically optimize soil nutrient structure, so as to improve carbon sequestration efficiency. This study mainly used the method of literature review and case analysis to systematically sort out the current situation of soil application of TCMR and its impact on crop growth, and focused on evaluating the potential of this synergistic returning mode in alleviating greenhouse gas emissions and enhancing farmland soil carbon sink capacity. The results showed that the combined application of TCMR and straw could significantly increase soil organic matter content, effectively improve acidified and saline-alkali soil, and promote crop yield and quality. As a major producer of straw and Chinese medicinal materials, the promotion of this technology can realize the large-scale resource utilization of two kinds of agricultural solid wastes and provide an innovative path for waste recycling. Their combined capacity for carbon emission reduction, carbon sequestration, and soil improvement is also of significant importance for achieving China’s “dual carbon” goals and promoting the sustainable development of agriculture, with the potential to simultaneously enhance crop yields and improve ecological quality.
To expand the application of attapulgite in the fertilizer field and enhance its added value, this review summarized the modification methods of attapulgite and its application research progress in fertilizers, to provide references for developing new fertilizers with low cost and high efficiency. The structural characteristics of attapulgite, common modification methods(thermal activation, acidification, surface organic modification, etc.), and their mechanisms were outlined. Emphasis was placed on analyzing the application effects, mechanisms, and existing challenges of modified attapulgite in various fertilizer systems, including slow-release fertilizers, controlled-release fertilizers and soil conditioners. Finally, future research directions for attapulgite-based functional fertilizers were prospected.
This study investigated the efficacy of agricultural and forestry biochar in mitigating chromium (Cr) toxicity in artificially contaminated soil through a 40-day passivation treatment. Biochars derived from different biomass sources and pyrolysis temperatures were applied to the contaminated soil at varying ratios for pot experiments with coriander. Soil and plant samples were collected and analyzed at 0, 7, 14 and 21 days after cultivation to assess Cr immobilization and bioavailability. The results demonstrated that rice straw biochar pyrolyzed at 200°C for 4 h exhibited the highest efficiency in reducing Cr toxicity, and the effect was the best at an 8% application rate. The acid-extractable Cr content in the soil decreased by 99.8% after 7 days, while the leaching concentration of Cr (VI) dropped from an initial 175.08 μg/g to undetectable levels. Furthermore, Cr was effectively stabilized in the soil, significantly inhibiting its accumulation in the roots, stems and leaves of coriander. These findings indicated a substantial reduction in both Cr toxicity and mobility. Risk Assessment Code (RAC) analysis confirmed that the environmental risks associated with Cr contamination were markedly reduced after 7 days of treatment with 4% and 8% rice straw biochar. The study highlighted that agricultural and forestry biochar could facilitate soil remediation by converting Cr into residual and less bioavailable forms, thereby reducing soil toxicity. Additionally, this approach supports the sustainable reutilization of agricultural and forestry biomass.
Freeze-thaw cycling is a distinctive natural phenomenon prevalent in cold climate zones, including high-latitude and high-altitude regions. The periodic fluctuations in hydrothermal conditions associated with freeze-thaw processes exert substantial impacts on the physicochemical properties and biological characteristics of environmental media, particularly soils. These effects manifest through both direct and indirect mechanisms: freeze-thaw actions directly modulate soil microbial activity while simultaneously influencing microbially-mediated soil processes. Within the context of black soil farmland ecosystems, freeze-thaw cycling plays a pivotal role in nutrient cycling dynamics, thereby significantly affecting crop cultivation and growth. To elucidate the nutrient cycling processes in agricultural soil ecosystems within freeze-thaw affected black soil regions, it is imperative to account for the influence of freeze-thaw actions. This paper systematically synthesized relevant domestic and international research findings, with particular emphasis on analyzing advancements in understanding how freeze-thaw processes affect soil microbial community structure and function, as well as soil enzyme activities. Furthermore, we examined the effects of freeze-thaw frequency and intensity on soil properties. The insights derived from this review provide theoretical foundations for the sustainable utilization and management of black soil resources in Northeast China under freeze-thaw climate conditions.
The study aims to evaluate the effects of three afforestation methods on soil organic carbon (SOC) and provide a scientific basis for ecological restoration and carbon sequestration management in sparse forest lands. In Qingtian County, Zhejiang Province, three afforestation approaches were implemented: single-species, two-species and multi-species (five species) plantations, followed by a comprehensive soil property analysis. The results showed that compared with single-species and two-species afforestation, multi-species afforestation significantly increased SOC content. Correlation analysis demonstrated that SOC levels were significantly associated with soil total nitrogen and available nitrogen. Multi-species afforestation enhanced SOC content in sparse forest lands through three synergistic mechanisms: increasing organic carbon input, improving soil nitrogen and potassium availability, and elevating soil enzyme activity. These findings advance scientific guidance for ecological restoration and carbon sequestration management in sparse forest lands, while underscoring the critical role of soil carbon-nitrogen-potassium coupling dynamics and microbial enzyme activity in soil carbon cycling.
To optimize the pesticide application parameters of plant protection drones, this study systematically evaluated the effects of different water application rates on the control efficacy against rice sheath blight and the economic benefits, aiming to provide a scientific basis for precise drone-based pesticide application. Using the DJI T40 drone, field experiments were conducted in Songjiang District, Shanghai, from 2023 to 2024. Three water application rate gradients (30, 45, and 67.5 L/hm2) were set, with pesticides applying at the jointing and heading stages of rice, and the control efficacy in terms of diseased plant rate and disease index was monitored. (1) At the jointing stage, there were no significant differences in control efficacy among the gradients (diseased plant control efficacy: 85.57%-87.68%; disease index control efficacy: 89.86%-91.34%). (2) At the heading stage, the control efficacy at 30 L/hm2 was significantly lower than that at other gradients (P< 0.05), while there was no significant difference between 45 L/hm2 and 67.5 L/hm2 (P>0.05). In 2023, the diseased plant control efficacy ranged from 79.71% to 91.99%, and the disease index control efficacy ranged from 89.47% to 94.95%. In 2024, 7 days after pesticide application, the diseased plant control efficacy was 78.86%-95.01%, and the disease index control efficacy was 85.30%-94.93%; 15 days after application, the diseased plant control efficacy was 73.17%-93.12%, and the disease index control efficacy was 77.38%-92.46%. (3) In terms of economic benefits, the operation efficiency showed a decreasing trend with the increase of water application rate (30L: 4.0 hm2 /h→67.5 L: 2.67 hm2 /h), and the control cost increased by 71.4% with the increase of water application rate (from 1050 to 1800 yuan per application). A differentiated water application strategy is recommended: since the water application rate at the jointing stage has no significant impact on the control efficacy, 30 L/hm2 is recommended (balancing efficiency and cost); as the water application rate at the heading stage has a significant impact on the control efficacy, 45 L/hm2 is preferred (balancing control efficacy and economy).
Annexins (Anx) are a class of calcium-dependent phospholipid-binding proteins with unique domains, which play regulatory roles in cellular life activities and are associated with various diseases. This study mainly reviews the structure and classification of Anx, with a focus on the research progress of its immune response mechanisms in important zoonotic helminth infections such as Angiostrongylus cantonensis, Taenia solium, Echinococcus granulosus, Taenia multiceps, and Schistosoma. These studies revealed that Anx participated in immune evasion and promoted the survival of worms in the host through various mechanisms such as anticoagulation, regulation of immune cell apoptosis, and interference with the host coagulation system. It is of great biological significance and application value to deeply understand the mechanism of Anx in zoonotic helminthiasis and provide a theoretical basis for the development of new diagnostic targets, treatment strategies and vaccine design.
Lactic acid bacteria, as beneficial microorganisms, are of great significance in ensuring food safety, improving quality, and promoting health in the food industry. To clarify the mechanism of action of lactic acid bacteria in ensuring food safety and explore effective ways to enhance their application efficiency, this study summarizes current research on lactic acid bacteria in alleviating microbial contamination and degrading toxic and harmful substances, and discusses the feasibility of improving the growth efficiency of lactic acid bacteria and the quality of fermentation products by optimizing medium components (including the selection and combination of carbon sources, nitrogen sources, minerals, and growth factors). Meanwhile, it analyzes the current challenges in balancing production costs with meeting consumers' demands for food safety, nutrition, and flavor. Future research will focus on developing economical and efficient composite medium systems to strengthen their role in enhancing the food safety functions of lactic acid bacteria. This study aims to provide a theoretical reference for the selection and research of raw materials for food-applied lactic acid bacteria culture media.
To investigate nutritional quality changes law of dual-purpose sweet potato varieties during storage and provide theoretical guidance for further utilization (processing, consumption, etc.), this experiment used three varieties 'Shangshu No.19', 'Luoshu No.11' and 'Luoshu No.16' as test materials. Statistical trait data were collected during storage, and nutritional quality data were obtained using colorimetric methods. Statistical software was employed for data analysis. The results showed that a significant negative correlation existed between marketable tuber rate and dry matter consumption rate (coefficient of determination: 0.99874). Moisture consumption rate showed significant annual variations (P<0.01). Trends in nutritional quality indices varied complexly among varieties during storage. Ash content and crude protein content exhibited a highly significant positive correlation (coefficient of determination: 0.9819), while no unified correlations were observed among other quality indices. Dry matter consumption rate serves as a relatively precise indicator for evaluating sweet potato storability. For industrial starch extraction, targeted cultivar selection is required based on specific storage duration requirements. The complex dynamics of nutritional quality in dual-purpose sweet potatoes during storage warrant further investigation.
In recent years, the application of deep learning algorithms in the field of image recognition has gradually expanded into agricultural production, particularly in the area of crop disease detection. Leveraging transfer learning techniques within deep learning, a method for identifying corn leaf diseases based on an improved MobileNetV3 model has been proposed. Pre-trained weights from the ImageNet dataset were transferred to the target dataset, and the model was further optimized. During the optimization process, the original SE (Squeeze-and-Excitation) module was replaced with a CBAM (Convolutional Block Attention Module) attention module, and dilated convolutions were introduced into the convolutional layers to increase the receptive field. After training, an optimal model for corn leaf disease identification was obtained. After applying transfer learning, the model's accuracy on the training set increased from 96.30% to 98.20%, with an improvement of 1.9 percentage points. With further optimization, the accuracy reached 99.09%, demonstrating improved classification performance. This enhancement not only retains the lightweight characteristics of MobileNetV3 but also significantly boosts the performance of corn leaf disease identification.
In order to conduct a dynamic analysis of the fishery resources in Poyang Lake, a study on the resource status of Coilia nasus and its environmental carrying capacity under extreme low water levels was carried out. Based on the fishery resource survey data, the length-based Bayesian biomass estimation method was used to obtain the relevant parameters of Coilia nasus population, and the Ecopath model was applied to estimate its environmental carrying capacity under extreme low water levels. The results showed that the average L∞ of Coilia nasus in Poyang Lake was 374 (368-381) mm; the resource status index E (F/Z) was 0.067, far less than 0.5; the ratio of current biomass to original biomass (B/B0) was 0.89 (0.225-2.6), which was greater than 0.5; from 2018 to 2022, L∞ and B/B0 showed an upward trend, while the ratio of fishing mortality to natural mortality (F/M) showed a downward trend, indicating that the resources of Coilia nasus showed a recovery trend after the fishing ban. The Ecopath model revealed that environmental carrying capacity of Coilia nasus in Poyang Lake was 5.03 t/km2 (approximately 1136.78 t), while its current biomass was 2.83 t/km2 (approximately 639.58 t). Currently, the overall resources of Coilia nasus in Poyang Lake are in an undeveloped state. The environmental carrying capacity has restricted the population growth of Coilia nasus to a certain extent, but there is still a large growth space for its population. The results of this study provide a scientific basis for the sustainable management of Coilia nasus resources and the protection of the entire lake ecosystem in Poyang Lake.
