Scientia Agricultura Sinica

Yield Gain Analysis of Wheat Varieties in Sichuan from 2000 to 2020

LUO JiangTao, ZHENG JianMin, DENG QingYan, LIU PeiXun, PU ZongJun

Scientia Agricultura Sinica. 2024, 57(20): 3945-3956. doi:10.3864/j.issn.0578-1752.2024.20.001

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【Objective】Analyzing the yield and yield related traits of Sichuan wheat varieties from 2000 to 2020, providing reference for genetic improvement of yield in Sichuan wheat varieties. 【Method】From 2019 to 2022, a community trial design was used to measure the yield and related traits of 145 wheat varieties in Sichuan Province since 2001 to 2016, as well as 60 high-yield wheat varieties (Varieties with top yields in regional trials in Sichuan Province over the years) since 2000 to 2020. This data was used to analyze the trend of yield and yield related trait changes in Sichuan wheat cultivars cultivated from 2000 to 2020. 【Result】145 Sichuan wheat varieties from 2001 to 2016 have an average annual genetic gain of 37.20 kg·hm^-2 or 0.66% in yield. Grain number per spike and effective spike number per unit area showed an increasing trend, while thousand grain weight and plant height showed a decreasing trend. Correlation analysis showed that effective spike number per unit area was positively correlated with yield. Path analysis showed that the continuous increase of effective spike number per unit area (annual increase 0.42×10⁴/hm² or 0.13%) was the main factor for the increase of yield potential of high-yielding varieties. The average annual yield genetic gain of 60 high-yield wheat varieties from 2000 to 2020 was 61.10 kg·hm^-2 or 0.89%, the effective spike number per unit area showed an increasing trend, the plant height showed a decreasing trend, and the grain number per spike and thousand grain weight had almost no change. Correlation analysis shows that there was a significant positive correlation between yield and the number of effective ears per unit area. Path analysis showed that the continuous increase in effective spike number per unit area (with an average annual increase of 1.80×10⁴/hm² or 0.51%) was also a major factor in improving the yield potential of 60 high-yield wheat varieties in Sichuan from 2000 to 2020. 【Conclusion】The improvement and breeding of wheat yield heritage in Sichuan Province has made some progress, especially the improvement effect of high yield breeding is remarkable, and the yield level of wheat varieties in Sichuan Province is gradually increasing. The continuous increase in effective ears per unit area was the main factor for improving the yield potential of Sichuan wheat varieties. High grain number per spike and thousand grain weight are important foundations for high yield in Sichuan wheat, but their genetic improvement is in a bottleneck period. Increasing the effective spike number per unit area is the key to furtherly improve the yield of wheat in Sichuan.

Evaluation of High Temperature Tolerance and Selection of Sesame (Sesamum indicum L.) Cultivars at Full Flowering Stage Based on Principal Components-Cluster Analysis

RONG YaSi, LI Feng, ZHANG PengYu, WANG DongYong, SU XiaoYu, TIAN Yuan, GAO TongMei

Scientia Agricultura Sinica. 2024, 57(20): 3957-3973. doi:10.3864/j.issn.0578-1752.2024.20.002

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【Objective】To understand the effects of high temperature stress on the agronomic traits, yield, its components and grain quality of sesame, to accurately evaluate the high temperature tolerance level of different sesame varieties at full flowering stage, and to screen the high temperature tolerant sesame varieties.【Method】24 sesame varieties were treated with normal temperature (CK) and high temperature stress(H) at full flowering stage for 7 days. The agronomic traits such as plant height, initial capsule site, number of capsules per plant, number of capsules per capsule, 1000-grain weight, yield per plant and quality indexes such as water content, oil content and protein content were measured at maturity stage. The heat tolerance of different sesame varieties at full flowering stage was comprehensively analyzed and evaluated by means of principal component and cluster analysis.【Result】Different varieties, temperature treatments and interactions had significant effects on the indexes of sesame. After high temperature stress, compared with CK, the yield per plant, 1000-grain weight, number of capsules per plant, number of capsules per capsule, initial capsule site, capsule length and plant height of sesame decreased by 33.47%, 13.62%, 7.76%, 5.75%, 2.61%, 1.64% and 1.40%, respectively. Among which 1000-grain weight and yield per plant decreased the most, and the differences reached significant level. The difference of end length and protein content was no significant, which was 13.43% and 1.55% lower than that of the CK. The water content and oil content increased by 0.90% and 0.17% respectively compared with CK, and the difference was not significant. There is a certain correlation between the high temperature tolerance coefficients of different varieties and various indexes. The high temperature resistance coefficient was analyzed by principal component analysis, and five independent comprehensive indexes were established, and the contribution rates were 30.74%, 25.82%, 13.18%, 10.12% and 8.33%, respectively, reflecting 88.19% of the original information. The weight of each index was calculated by component matrix and eigenvalue, and the physiological comprehensive index model of high temperature stress (HTSPCI) was constructed. According to the cluster heat map analysis of high temperature tolerance coefficient of each individual index, 24 sesame germplasm resources were divided into 4 grades: high temperature resistant type, medium high temperature tolerance type, medium heat sensitive type and heat sensitive type, respectively. And the yield loss rate per plant (X6) of 6 high temperature resistant varieties was ≤9.50%, 6 medium high temperature resistant varieties was 9.50%<X6≤30%, 10 medium heat sensitive varieties was 30%<X6≤70% and 2 heat sensitive varieties was X6>70%.【Conclusion】High temperature treatment significantly affected the growth and development of sesame at full flowering stage. A comprehensive index model of high temperature stress was established by combining agronomic traits and quality indexes with principal components-cluster analysis, and 6 varieties with high temperature tolerance were selected, which could be used to evaluate the high temperature tolerance of different sesame varieties.

Oat Plant Height Estimation Based on a Dual Output Regression Convolutional Neural Network

ZHANG JianLong, XING WenWen, YE ShaoBo, ZHANG Chao, ZHENG DeCong

Scientia Agricultura Sinica. 2024, 57(20): 3974-3985. doi:10.3864/j.issn.0578-1752.2024.20.003

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【Objective】 Oat plant height affects the productivity per plant and the yield per unit area together with planting density. This study explores automatic, real-time, and precise methods for acquiring oat plant height in a field environment, aiming to provide technical references for the automated field management of oat. 【Method】 Firstly, an oat depth image acquisition system was built based on Intel RealSense D435 depth camera and LabVIEW software development platform. Taking Oat ‘Pinyan No. 4’ as the research object, 26 376 modeling data and 2 205 test data were obtained during the whole oat growth process. The average and highest plant height of oats in each depth image were measured with a scale. The quantity of modeling data and test data in each height range of oat plant was relatively balanced. The images were preprocessed by high restoration, grayscale and scaling. Each image was tagged with two labels, one for the average and one for the highest plant height of the oats in the image. Then, based on 8 classical convolutional neural network models, the last layer (classification layer) of each network model was removed, and two fully connected layers with single nodes and no activation function were added to construct the double output regression convolutional neural network estimation model. Mean square error (MSE) was used to evaluate the accuracy of each model in estimating oat plant height. Finally, based on the TensorFlow deep learning platform, Modified EfficientNet V2L was selected as the estimation model by 5-fold cross-validation using the modeling data. 【Result】 The generalization performance of Modified EfficientNet V2L model to estimate oat plant height was investigated using test data not involved in model training. The mean absolute error (MAE), root mean square error (RMSE) and mean relative error (MRE) to estimate oat average plant height were 2.30 cm, 2.90 cm and 4.4%, respectively. Meanwhile, the MAE, RMSE and MRE to estimate highest plant height was 2.24 cm, 2.82 cm and 4.1%, respectively. The average estimated time of the model was 52.14 ms. The accuracy of estimating crop plant height using this method was similar to that of existing methods. However, when estimating crop plant height used this method, once the estimation model was trained, the average and maximum crop plant height could be automatically estimated by inputting the pre-processed crop depth image, and the average estimation time could meet the real-time requirements of crop plant height acquisition. The relative errors in estimating average plant height and maximum plant height of oat showed a general decline trend with the increase of crop plant height. This might be because when crop plant height was low, the estimated results were more affected by soil fluctuation. The results of feature map visualization showed that the model could estimate plant height according to the height and contour of oat in depth image. Finally, an oat plant height estimation system was built based on 2023 Q1 version of LabVIEW software development platform. After depth camera acquiring oat depth images, the system could accurately estimate average and highest oat plant heights in real time without manual intervention, and the average estimation time was less than 0.1 seconds. The system could be used for crops irrigation and fertilization management. It could also be installed on the tractors to control the height of a sprinkler head during spraying, and to adjust the height of a cutting table during harvesting. 【Conclusion】 The depth image and double output regression convolutional neural network could be used to estimate oat plant height, and the accuracy could meet the production demand, so this method provided a basis for field management of oat crops.

Occurrence and Control of Migratory Pests

TANG Bin, LUO YanLin

Scientia Agricultura Sinica. 2024, 57(20): 3986-3988. doi:10.3864/j.issn.0578-1752.2024.20.004

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The Vibration Propagation Laws and Perception Behavior of Mating Calls of Nilaparvata lugens

WEI Qi, SHAN Yao, FENG ZeLin, HE JiaChun, LAI FengXiang, WAN PinJun, WANG WeiXia, YAO Qing, BIAN Lei, FU Qiang

Scientia Agricultura Sinica. 2024, 57(20): 3989-3997. doi:10.3864/j.issn.0578-1752.2024.20.005

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【Objective】The objective of this study is to explore the vibration propagation laws of mating calls of the brown planthopper (BPH), Nilaparvata lugens, and to provide the theoretical basis and practical guidance for the development and optimization of novel techniques for physical pest control.【Method】Simulating a paddy field scenario, using the root mean square (RMS) as the measurement index of vibration intensity, the PDV-100 digital laser vibrometer was applied to test and analyze the propagation and attenuation characteristics of vibrations generated by different types of loudspeakers (as vibration sources) in water, air, and on rice plants. Based on the principle of substrate-borne vibration in insects, a steel needle point-touch method was used to play back female mating calls at varying intensities, which aimed to test the response rate of males during their mating active period and determine the range of vibration intensity they could perceive.【Result】When the vibration source was placed in water or air, the vibration intensities of the sinusoidal waves on rice plants decreased with increasing distance within the range of 10 to 500 cm. However, except for the position 10 cm from the vibration source, there was no significant difference in vibration intensity between the two modes at other positions (60-500 cm). At 60 cm, the intensity decreased by 84.87% in water and 73.08% in air compared to that at 10 cm. Furthermore, the application of higher-power directional loudspeakers revealed significantly extended propagation distances of sinusoidal wave signals in the air. Vibration sources with 20 and 30 W output power were attenuated by 87.27% at 15 m and 66.72% at 20 m, respectively. The vibration intensity on rice plants when playing back pre-recorded female and male courtship vibration signals showed no significant difference and increased with the signal strength of the vibration source, following an exponential function relationship. Additionally, the response rate of N. lugens males to female signals of different intensities showed significant differences. When the vibration velocity ranged from 782.2 to 835.9 μm·s^-1, over 83% of male insects exhibited a calling response; however, when the vibration velocity was between 335.2 and 425.4 μm·s^-1 or lower, fewer than 47% of males responded.【Conclusion】The disruptive vibrational signals can propagate to rice plants through the airborne pathway, with greater vibration source intensity resulting in farther propagation distances. The vibration conduction characteristics of rice plants are similar at different growth stages, but rice stems conduct vibrations more effectively than leaves. The results of response tests of N. lugens adults to different vibration intensities can serve as a basis for evaluating the effectiveness of disruptive vibrational signals in controlling N. lugens in the future.

Effect of Rice Varieties on the Preference of Nilaparvata lugens to Rice Plants Infested by Chilo suppressalis

CAI YuBiao, ZHANG KunJie, WANG YaXuan, LAI FengXiang, HE JiaChun, WAN PinJun, FU Qiang

Scientia Agricultura Sinica. 2024, 57(20): 3998-4006. doi:10.3864/j.issn.0578-1752.2024.20.006

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【Objective】It has been reported that Nilaparvata lugens (brown planthopper, BPH) exhibits a preference of endangering rice plants infested by Chilo suppressalis (striped stem borer, SSB). However, it remains unclear whether this phenomenon is influenced by the developmental stage of N. lugens and the rice variety. This study aims to investigate the effects of rice varieties and developmental stages of N. lugens on the preference for C. suppressalis-infested rice plants, as well as how volatiles mediate this behavior, so as to provide a scientific basis for formulating green pest control strategies.【Method】Through indoor choice experiments, the attraction of different developmental stages of N. lugens (including 3rd-4th instar nymphs, newly emerged females, gravid females) to nine rice varieties, including Zhongzheyou 8, both damaged and undamaged by C. suppressalis, was observed. Based on these observations, representative varieties showing significant differences in attraction were selected for further analysis. RT-qPCR was used to detect changes in the expression of volatile synthesis-related genes in three rice varieties (Zhongzheyou 8, 9311, and Minghui 63) following pest infested.【Result】Among the nine rice varieties, different developmental stages of N. lugens consistently showed a preference for rice plants infested by C. suppressalis, although this preference varied among rice varieties. For instance, newly emerged female N. lugens exhibited a significantly higher preference for Minghui 63 compared to Yongyou 538. Gene expression analysis revealed a significant increase in the expression levels of volatile synthesis-related genes OsCAS, OsLIS, OsHPL3, and OsRCI-1 in response to C. suppressalis infestation. However, when different developmental stages of N. lugens were co-infested with C. suppressalis, the expression levels of these genes could either increase or decrease compared to plants infested only by C. suppressalis, with specific effects depending on the developmental stage of N. lugens.【Conclusion】The preference of N. lugens for rice plants infested by C. suppressalis was commonly observed across the nine tested rice varieties. However, significant differences in the degree of preference were noted among different developmental stages of N. lugens across these varieties. Notably, variations in preference among developmental stages of N. lugens were primarily observed in the selection of rice varieties Yongyou 538, Zhongzheyou 8, and Minghui 63 by newly emerged female. Infestation only by C. suppressalis or in conjunction with N. lugens resulted in increased expression levels of the genes OsCAS, OsLIS, OsHPL3, and OsRCI-1, indicating that pest infestation in rice plants can regulate the synthesis of rice volatiles, thereby influencing the host selection behavior of N. lugens.

Comparative Analysis of the Toll Receptor Gene Families in Three Species of Rice Planthoppers

ZHONG ZiChun, WU HongXin, ZHANG Jie, GUO YuJing, HE LiuYan, XU XiaoXia, JIN FengLiang, PANG Rui

Scientia Agricultura Sinica. 2024, 57(20): 4007-4021. doi:10.3864/j.issn.0578-1752.2024.20.007

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【Objective】The Toll receptor is one of the key effector factors in the Toll signaling pathway of the innate immune system in insects. This article aims to identify the Toll receptor genes of three types of rice planthoppers (Nilaparvata lugens, Sogatella furcifera, and Laodelphax striatellus), explore the potential functions of the Toll receptor in these three species, and investigate the interspecies differences, so as to provide a theoretical basis for the study of the immune development of rice planthoppers and for the control and prevention of these pests.【Method】Bioinformatics methods were used to identify Toll receptor genes from the genomes of three species of rice planthoppers, and the gene structure and characteristics, physicochemical properties and structural domains of the encoded proteins, chromosome localization and phylogenetic evolutionary relationships were analyzed. Artificial intelligence software AlphaFold 3 was used to predict the three-dimensional structure of Toll receptors and compare it with the known structures and functions of Toll receptors from other species to predict their potential functions and interspecific functional differentiation. Transcriptome data were used to quantitatively analyze the expressions of Toll receptor genes in different tissues and at different developmental stages.【Result】A total of 6, 7, and 6 Toll receptor genes were identified in the genomes of N. lugens, S. furcifera, and L. striatellus, respectively, all of which are distributed on chromosomes 1, 4, and 7, with a clear distribution pattern. The Toll gene family in the three species of rice planthoppers is distributed with one gene on chromosomes 1 and 4, and the rest on chromosome 7. The coding sequence lengths of the Toll receptor genes in the three species of rice planthoppers range from 2 676 to 4 158 bp, with the number of exons ranging from 1 to 7, and the encoded protein sequence lengths range from 891 to 1 385 aa, with molecular weights ranging from 103.31 to 158.25 kDa and theoretical isoelectric points ranging from 5.42 to 6.54. Phylogenetic development analysis showed that the Toll receptor gene family of the three species of rice planthoppers can be divided into six subfamilies, which are homologous to the Toll, Toll6, Toll7, Tollo (Toll8), and Toll9 of other insects. The comparison analysis of the extracellular structures predicted by AlphaFold 3 with those of Toll receptors from other species showed that two Toll receptors in the Toll receptor gene family of S. furcifera were potentially related to virus interactions, one in the Toll receptor gene family of L. striatellus, and none in the Toll receptor gene family of N. lugens. Transcriptome quantitative results showed that the Toll receptor genes in the three species of rice planthoppers were expressed in different tissues and at different developmental stages, suggesting that they may have different functions and participate in different divisions of labor.【Conclusion】A total of 19 Toll receptor genes were identified in three species of rice planthoppers, and their related structures and functions were analyzed and predicted. The study revealed potential differences in the roles played by Toll receptors in the development and immune response, particularly in virus immunity, within the insect body among these three species of rice planthoppers.

Effects of miRNA on Gene Expression of Sphingolipids Metabolism and Small RNA Analysis of Silencing NlSPT1 and NlSMase4 in Nilaparvata lugens

WANG Ni, SHI ZheYi, YOU YuanZheng, ZHANG Chao, ZHOU WenWu, ZHOU Ying, ZHU ZengRong

Scientia Agricultura Sinica. 2024, 57(20): 4022-4034. doi:10.3864/j.issn.0578-1752.2024.20.008

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【Background】Sphingolipids are the second major type of membrane lipids and mediate various biological processes as signal transducers, including cell growth, development, reproduction and apoptosis. Sphingolipid metabolism is tightly regulated by sphingolipid metabolizing enzymes to maintain the homeostasis of metabolism in vivo.aaaaa【Objective】The objectives of this study are to investigate the relative transcript levels of genes related to the sphingolipid metabolism pathway after silencing of the core components of microRNA (miRNA) biosynthesis pathway, NlAgo1, NlDicer1 and NlDrosha by RNA interference (RNAi), and analyze the differentially expressed miRNAs after silencing of serine palmitoyltransferase 1 (SPT1) and sphingomyelinase 4 (SMase4) gene combined with small RNA sequencing of Nilaparvata lugens, explore the role of miRNAs in the sphingolipid metabolism of N. lugens, and to provide a new molecular target for pest control.【Method】RNAi was performed with double stranded RNAs (dsRNAs) targeting NlAgo1, NlDicer1 and NlDrosha at 1 day post adult eclosion (1 PAE), respectively, and dsGFP was used as control. The ovaries at 5 PAE were dissected and β-actin was used as internal reference gene, the transcript levels of genes related to the sphingolipid metabolism pathway were detected by reverse-transcription quantitative PCR (qRT-PCR). miRNAs that may regulate the expression of NlSPT1 and NlSMase4 were predicated based on small RNA libraries combined with miRNA-target prediction software. Differentially expressed miRNAs after the silencing of NlSPT1 and NlSMase4 were identified and the target gene enrichment was analyzed by small RNA sequencing.【Result】RNAi-mediated silencing of NlAgo1, NlDicer1 or NlDrosha significantly up-regulated the expression of genes related to the sphingolipid metabolism pathway, including NlSPT1 and NlSMase4 in ovaries. Target gene prediction revealed 6 miRNAs and 13 miRNAs that could bind NlSPT1 and NlSMase4. The target genes of differentially expressed miRNAs that silencing NlSPT1 and NlSMase4 were significantly enriched in biological processes, including nuclear and protein binding, as well as metabolic pathways such as endocytosis, endoplasmic reticulum processing, MAPK signaling pathway, TOR signaling pathway, apoptosis, and lipid metabolism.【Conclusion】NlAgo1, NlDicer1, and NlDrosha-dependent miRNAs affect sphingolipid metabolism by influencing the expression of genes encoding sphingolipid metabolizing enzymes. The silencing of NlSPT1 and NlSMase4 induced changes in miRNA expression levels in N. lugens ovaries. These research results can provide a theoretical basis for pest control based on sphingolipid metabolism genes.

Survival Adaptability and Damage Potential of Spodoptera frugiperda in the Soybean-Maize Strip Intercropping

XIA Yang, HAN GuangJie, LI ChuanMing, LIU Qin, ZHANG Nan, HUANG LiXin, LU YuRong, XU Bin, XU Jian

Scientia Agricultura Sinica. 2024, 57(20): 4035-4044. doi:10.3864/j.issn.0578-1752.2024.20.009

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【Objective】This study aims to investigate the feeding metabolic characteristics and migration behavior of Spodoptera frugiperda on soybean and maize, as well as to clarify the feeding rules and potential damage risks of S. frugiperda in the soybean- maize strip intercropping.【Method】The host plants were Xudou 18 and Jiangyu 877, which were recommended for soybean-maize strip intercropping planting in Jiangsu Province. The effects of soybean leaves and maize leaves on feeding preference, growth, oviposition quantity, oviposition selectivity, digestive enzyme activity and digestive metabolism of S. frugiperda were determined by laboratory tests. Field inoculation experiment was conducted to investigate the migration distance and range of S. frugiperda over time under the “2+4” intercropping of maize and soybean, and the potential risk of damage was evaluated based on the migration dynamics.【Result】S. frugiperda exhibited a clear preference for feeding on maize leaves, with 63.89% of individuals selecting to feed on maize leaves, which was 1.77 times higher than the number of individuals that selected to feed on soybean leaves, and the difference was significant. S. frugiperda could complete its life cycle by feeding on both soybean leaves and maize leaves, but the larval development period of those feeding on maize leaves was 14.82 d, which was 2.54 d shorter than those feeding on soybean leaves. The single female fecundity of S. frugiperda feeding on maize leaves was 679.50 eggs, which was significantly increased by 26.58% compared to feeding on soybean leaves. Adult females preferred to oviposit on maize leaves, with the average egg mass number and single female oviposition of 5.67 masses and 521.67 eggs, respectively, which were 1.70 and 2.04 times higher than those on soybean, and the differences were significant. The lipase activity of S. frugiperda feeding on soybean leaves was 9.84 U·g^-1, significantly higher than that of those feeding on maize leaves (6.47 U·g^-1), while there was no significant difference in protease and amylase activities between the two. The approximate digestibility of S. frugiperda feeding on soybean leaves was 63.40%, which was significantly lower than that of those feeding on maize leaves (69.26%). However, there was no significant difference in food utilization efficiency, food conversion efficiency, and relative growth rate between the two. Field investigations after egg mass inoculation revealed that in the “2+4” strip intercropping pattern of maize and soybean, S. frugiperda primarily infested the maize plants, exhibiting “vertical migration” within the maize rows, and did not spread to the neighboring soybean plants.【Conclusion】S. frugiperda exhibited distinct differences in feeding adaptation and oviposition preference between soybean and maize, displaying a stronger preference and utilization ability for maize compared to soybean. Under the “2+4” strip planting pattern of maize and soybean, S. frugiperda primarily inflicted damage on maize. Therefore, in practical agricultural production, it is crucial to enhance monitoring and control measures for S. frugiperda, particularly during the critical growth stages of maize, to mitigate the risk of damage.

The Increasing Temperature Accelerated the Population Growth of Rhopalosiphum padi and Sitobion avenae by Wheat Rhizosphere Microorganisms

JIANG YaNan, QI FangJian, LI WeiWei, CHEN JuLian, TAN XiaoLing

Scientia Agricultura Sinica. 2024, 57(20): 4045-4056. doi:10.3864/j.issn.0578-1752.2024.20.010

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【Objective】Climate warming can affect the occurrence and damage caused by wheat aphids. Rhopalosiphum padi and Sitobion avenae as the main pests of wheat in the Huang-Huai-Hai region of China, their population development and reproduction are affected by warming. This study aims to investigate whether climate warming will change the wheat rhizosphere microorganisms, which would indirectly affect the development and reproduction of R. padi and S. avenae.【Method】At the Yuanyang experimental station in Henan Province, infrared radiation heaters were hung to simulate a temperature increased by 2 ℃, and the number of wheat aphids occurring was investigated after the wheat returned to the greening stage. During the wheat jointing stage, rhizosphere microorganisms were collected and then brought to the laboratory to obtain the mixed microbial solution. The population dynamics and age-stage two-sex life table of two aphid species were tested by irrigating wheat with mixed solution. The mixture of rhizosphere microorganism was irrigated, and then aphids were inoculated. The number of aphids was recorded after 5 consecutive observations. For life table experiments, individual aphid of two wheat aphid species was fixed onto the 2nd leaf of wheat using ecological boxes, and the molting, instar and mortality of nymphal aphid were observed and recorded every day. At the same time, the reproduction and mortality of adult aphid were also recorded.【Result】Under different treatments, the population dynamics of R. padi and S. avenae were increasing continuously. With increasing investigation frequency, the increase of aphids gradually increased with irrigating the rhizosphere microorganisms of the elevated field compared with that at the ambient field. Rhizosphere microorganisms in the elevated field significantly increased the total mean number of R. padi and S. avenae, and compared with S. avenae, the increase of R. padi was greater, which increased by 4.49 times of S. avenae. The results of the population life table showed that the rhizosphere microorganisms in the elevated field significantly shortened the mean generation time, population doubling time, preadult duration, and oviposition duration of R. padi, while significantly increasing its intrinsic rate of increase, finite rate of increase and offspring. In addition, rhizosphere microorganisms in the elevated field significantly improved the survival rates of S. avenae at all developmental stages.【Conclusion】Warming promotes the growth, development, and reproduction of R. padi, enhances the survival rate of S. avenae, and accelerates the population growth of both aphid species, respectively, by affecting rhizosphere microorganisms, which may lead to changes in the migratory behavior of the aphids. These findings provide initial insights into the outbreak mechanism of wheat aphids under climate warming, and offer valuable references for predicting and assessing wheat aphid occurrences under future climate warming.

AQPs Characteristics of Megoura crassicauda and Their Expression Changes in Response to High Relative Humidity Stress

SUN SiSi, MA Wu, SI HuiRu, WANG XianZhong, LIU Qiang, LUO YanLin, CHEN XiaoYuLong, TANG Bin

Scientia Agricultura Sinica. 2024, 57(20): 4057-4070. doi:10.3864/j.issn.0578-1752.2024.20.011

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【Objective】At present, crop pests are more adaptable to high relative humidity. Aquaporin (AQP) is a membrane protein that is necessary for insects to maintain water balance in the body. The objectives of this study are to screen two McAQP sequence structures by transcriptome sequencing through high relative humidity stress, clarify the AQP characteristics of Megoura crassicauda and the expression changes in response to high relative humidity stress combined with real-time fluorescence quantitative PCR (qRT-PCR) verification, and to provided a theoretical basis for further exploring the gene function of AQP.【Method】The environmental relative humidity (RH) of 60%, 75% and 90% were set to cultivate M. crassicauda. The growth and development were observed, the relative expression of genes and the content of related substances in the body were detected. Based on two McAQP sequences (named as McAQP X1 and McAQP X2, respectively) obtained from comparative transcriptome sequencing of M. crassicauda, the physicochemical property, sequence structure, and the homology with other insects were analyzed by bioinformatics methods. Finally, qRT-PCR was used to determine the relative expression of AQP X1, AQP X2, Vg and VgR under long-term stable high relative humidity stress and 24 h emergency high relative humidity stress.【Result】Compared with RH 60% and RH 75%, the fecundity of M. crassicauda under RH 90% was significantly reduced, but there was no significant difference in development duration and survival rate. With the increase of relative humidity, the water content of M. crassicauda decreased, and the special phenotype phenomena such as body color change and long wing appeared. The molecular weights of McAQP X1 and McAQP X2 are 33.89 and 28.94 kDa, the theoretical isoelectric points are 5.36 and 5.32, and the protein lengths are 308 and 272 aa, respectively. On the multistage structure, McAQP is arranged by six long alpha helices via counterclockwise rotation to form a barrel channel, whereas four monomers form a tetramer to exercise function. The relative expression of McAQPs quantified by qRT-PCR showed that both McAQP X1 and McAQP X2 were up-regulated with increasing relative humidity, which was generally consistent with the transcriptome sequencing results. Meanwhile, under long-term stable high humidity stress, both Vg and VgR were up-regulated under RH 75% and down-regulated under RH 90%. Under 24 h emergency high humidity stress, Vg expression level was down-regulated with increasing humidity, while VgR was up-regulated under RH 90%.【Conclusion】High humidity environment affects the reproduction, water content and body color of M. crassicauda. The aquaporin sequence structure in subfamily II is relatively conservative, without strong species-specific differentiation. NPA site is important for the function of aquaporin, and the asparagine residue plays a structural role for water molecules through the central channel. It is speculated that the expression change of AQPs may be an important means for M. crassicauda to cope with humidity changes.

Analysis of Population Dynamics and Migration Status of Ostrinia furnacalis Under Searchlight Trap and Ground Light-Trap

WANG LiLi, LUAN BingHui, WANG HongTao, WANG PeiSong, GAO XingXiang, LIU BaoYou

Scientia Agricultura Sinica. 2024, 57(20): 4071-4081. doi:10.3864/j.issn.0578-1752.2024.20.012

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【Objective】Ostrinia furnacalis is one of the most destructive migratory Lepidopteran pests, which seriously threatens the safety of maize production in China. The population dynamics and migration status monitored by ground light-trap and searchlight trap were compared and evaluated to provide a scientific basis for migration monitoring and early warning and control of O. furnacalis.【Method】Ground light-trap and searchlight trap were used to monitor the population of O. furnacalis in Yantai, Shandong from 2019 to 2023. Daily collection and statistics were carried out on the number of O. furnacalis from April 1 to October 31 each year. The population dynamics of O. furnacalis were analyzed by drawing monitoring curves. The up-lighting pattern of O. furnacalis was analyzed based on the percentage of daily trapped number to annual trapped number by ground light-trap and searchlight trap. The migration status of O. furnacalis was analyzed based on the phenomenon of “sudden increase and decrease” of migration insect populations and the ratio of the number of insects trapped by searchlight trap and ground light-trap.【Result】The number of O. furnacalis varied in different years and months, and the number trapped by searchlight trap was higher than that of ground light-trap. Pearson correlation analysis showed that there was no correlation between the annual total number of O. furnacalis trapped by ground light-trap and searchlight trap. The population dynamics of O. furnacalis monitored by ground light-trap and searchlight trap were basically consistent, but the peak of O. furnacalis trapped by searchlight trap was obvious, the start time was earlier than that by ground light-trap, and ended later. The up-lighting pattern of O. furnacalis was consistent between ground light-trap and searchlight trap, containing only three types: peak days, general occurrence days and non-occurrence days, and the peak day showed two peak stages with mid-July as the dividing point. O. furnacalis had two migration stages, with a low population and short duration from late May to late June, and a high population and long duration from late July to mid-September.【Conclusion】The population dynamics of O. furnacalis under ground light-trap and searchlight trap are consistent, indicating both methods are reliable for monitoring the dynamics of O. furnacalis. However, searchlight trap has more advantages in monitoring the early migration status of O. furnacalis because of its large number of insects, obvious peak of insects, early first peak appearance and long peak period. Searchlight trap can be used for timely monitoring the occurrence of O. furnacalis to prevent pest. The up-lighting pattern of O. furnacalis trapped by ground light-trap and searchlight trap is consistent with two peaks, so both traps can be used for monitoring. O. furnacalis migrates northward from late May to late June, and southward from late July to mid-September in Yantai. Therefore, monitoring and early warning and prevention can be strengthened in advance in the migration path to govern the migratory population of O. furnacalis.

Characteristics of phoD-Harboring Microbial Communities Under Long-Term Fertilization and Its Effects on Organic Phosphorus Fractions in Black Soil

SHEN WenYan, ZHANG NaiYu, LI TianJiao, SONG TianHao, ZHANG XiuZhi, PENG Chang, LIU HongFang, ZHANG ShuXiang, DUAN BiHua

Scientia Agricultura Sinica. 2024, 57(20): 4082-4093. doi:10.3864/j.issn.0578-1752.2024.20.013

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【Objective】The effects of long-term fertilization on the organic phosphorus (P_o) fractions and phoD-harboring microbial community characteristics in black soil were analyzed, as well as the response of P_ofractions to key microbial community characteristics was explored, so as to provide a theoretical basis for the efficient utilization of phosphorus in black soil and for the establishment of scientific fertilization strategies.【Method】Based on the long-term fertilization experiment started in 1989 in black soil, five fertilization treatments were selected: no-fertilizer (CK), nitrogen and potassium fertilizers (NK), nitrogen, phosphorus and potassium fertilizers (NPK), nitrogen, phosphorus and potassium fertilizers plus straw return (NPKS), and nitrogen and phosphorus and potassium fertilizers plus manure (NPKM). Soil samples collected from the 0-20 cm in 2018 were used for the study. Chemical sequential fractionation was performed to quantitatively analyze the P_o fractions. Illumina Miseq high-throughput sequencing platform and real-time PCR technology were used to qualitatively and quantitatively analyze the characteristics of phoD-harboring microbial community in soil. The relationships among phoD-harboring microbial community composition, P_o fractions and soil properties were comprehensively explored through correlation and variance partitioning analysis.【Result】(1) Except for NPKM treatment, there was no significant difference in total P_o content among different fertilization treatments, while there was a significant difference in the content and proportion in the total P_o of P_o fractions. Compared with CK, the content of labile P_o (LOP) and moderately labile P_o (MLOP) were significantly increased under NK and NPKM treatment, and the content of LOP and MLOP under NK increased by 108.7% and 27.5%, respectively, whereas that under NPKM treatment increased by 446.6% and 38.1%, respectively. Compared with the NPK treatment, the content of LOP and MLOP under the NPKS treatment were significantly reduced by 57.7% and 24.0%, respectively. (2) The fertilizer application with organic materials (NPKS and NPKM) changed the community composition of phoD-haboring microorganisms, but had no effect on their diversities. The NPKS treatment significantly increased the abundance of Pseudomonas, and the NPKM treatment significantly increased the abundance of Gemmatimonas. Meanwhile, the NPKS treatment also significantly increased the absolute abundance of phoD genes and alkaline phosphatase (ALP) activity. (3) Correlation analysis showed that there was a significant relationship among phoD-harboring microbial community composition, LOP and MLOP. Variance partitioning analysis showed that phoD-harboring microbial community composition individually explained 12.1% and 10.2% of the variations in the content and proportion of P_o fractions, whereas that were 58.5% and 58.7% jointly with ALP activity, and 67.5% and 64.7% jointly with soil organic matter (SOC), respectively. It could be seen that community composition and soil properties (ALP activity, SOC) jointly affected organic phosphorus components, and their impact effect was better than individual indicators.【Conclusion】Long-term fertilization applications altered phoD-harboring microbial community composition, which interacted with ALP activity and SOC explained changes in P_o fractions. Chemical fertilizer combined with straw could improve phoD-harboring microbial community characteristics and significantly increased alkaline phosphatase activity, thereby promoting P_o mineralization and improving the utilization efficiency of phosphorus in black soil.

Nitrogen Nutrition Diagnosis Method Based on Mobile Phone Image of Summer Maize Canopy

QI Xin, WANG Yang, HUANG YuFang, YE YouLiang, GUO YuLong, ZHAO YaNan

Scientia Agricultura Sinica. 2024, 57(20): 4094-4106. doi:10.3864/j.issn.0578-1752.2024.20.014

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【Objective】Convenient and accurate diagnosis of crop nitrogen (N) status is the key to achieve precise crop fertilization and rational utilization of N resources. In recent years, the application of digital cameras and other tools in crop nutrition diagnosis has attracted wide attention. In this study, the smart phone cameras were used to obtain maize canopy images, and nitrogen nutrition diagnosis technology based on mobile phone cameras was established and improved. The reliability of traditional image mean method and histogram method for nitrogen nutrition diagnosis was compared to find out the best model for nitrogen nutrition diagnosis of summer maize. 【Method】Based on the experiment of N fertilizer amount in the field, the canopy image of summer maize at jointing stage was obtained by smartphone camera. Six color indices, including G/R, G/B, NRI [R/(R+G+B)], NGI [G/(R+G+B)], NBI [B/(R+G+B)] and (G-R)/(R+G+B), were extracted from summer maize canopy images, and the histogram sensitive interval were established, respectively, to analyze their relationship with leaf N content and yield of maize. The determination coefficient (R²) and root mean square error (RMSE) were used to determine the relationship between the mean color index model and the histogram model. Mean absolute percentage error (MAPE) was used to simulate and estimate the stability and accuracy of leaf N content and yield in maize compared with different index models. Then, the N nutrition diagnosis model based on mobile phone camera acquisition of summer maize canopy images was established. 【Result】N application significantly affected leaf N content, yield, canopy image hue and vegetation coverage of maize. The peak b of the histogram changes with the increase of leaf N content. Compared with the mean color index method in canopy images, the index histogram method was suitable for N diagnosis among different varieties. The color index (G-R)/(R+G+B) histogram could better reflect crop coverage and overall color information. The index histogram also showed a good correlation with leaf N content and yield. Based on the neural network model to validate the accuracy evaluation indicators of the dataset, the MAPE and RMSE values of leaf N content and yield in maize in the exponential histogram model were lower than those in the exponential mean model, and the R² reached 0.753, which was greater than that in the exponential mean model. The validation results of the exponential histogram model showed a MAPE value of 5.80% and an RMSE value of 0.07, indicating high estimation accuracy and strong generalization ability. The results indicated that the color parameter index histogram of canopy images had higher accuracy and stronger robustness in estimating leaf N content and yield, and could effectively utilize the characteristics of maize leaf coverage, color, etc., with good stability.【Conclusion】Therefore, the neural network model established by using smartphones to obtain digital images of maize canopy and combining them with the color index histogram method of canopy images has good application effects and improves estimation accuracy. As a new method, it has good potential in rapid and non-destructive diagnosis of maize N nutrition and precise fertilization.

Effects of Combined Application Proportion of Cow Manure and Chemical Fertilizer on Soil Organic Carbon Pool and Enzyme Activity in Apple Orchard

ZHANG Yi, LIU Ying, CHENG CunGang, LI YanQing, LI Zhuang

Scientia Agricultura Sinica. 2024, 57(20): 4107-4118. doi:10.3864/j.issn.0578-1752.2024.20.015

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【Objective】This study aimed to study the effects of different proportions of cow manure and fertilizer on soil labile organic carbon components and carbon conversion related enzyme activities in apple orchard, and to reveal the mechanism of different fertilization methods on biological transformation of soil carbon pool, so as to provide the theoretical support for organic and inorganic scientific application and soil quality improvement in apple orchard.【Method】 Long-term positioning fertilization test was used as the platform. Six treatments were selected: no fertilizer (CK), 100% fertilizer (CF100), 25% cow manure with 75% fertilizer (CM25CF75), 50% cow manure with 50% fertilizer (CM50CF50), 75% cow manure with 25% fertilizer (CM75CF25), and 100% cow manure (CM100). Soil labile organic carbon components (particulate organic carbon, POC; microbial biomass carbon, MBC; readily oxidizing organic carbon, ROC) and carbon conversion related enzymes (α-D-glucosidase, AG; β-D-glucosidase, BG; Cellulase, CBH; Peroxidase, PER; Urease, UR) activity and other related indicators were measured.【Result】(1) The content of SOC, POC and ROC in soil increased with the increase of the proportion of organic fertilizer applied. CM50CF50 had the highest MBC content, which was 139.7% higher than that under CK. In the non-fertilized area, compared with CK, the POC content under CF100, CM25CF75, CM50CF50 and CM75CF25 decreased by 32.8%, 28.4%, 21.6% and 14.7%, respectively. The ROC content under CM50CF50 and CM75CF25 treatments decreased by 31.5% and 17.4%, respectively. The content of labile organic carbon in fertilized area was significantly higher than that in non-fertilized area under the same treatment. (2) Compared with CK, the α-D-glucosidase activity under CM25CF75, CM50CF50, CM75CF25 and CM100 was increased by 87.7%, 68.4%, 278.1% and 331.6%, respectively. The β-D-glucosidase activity under CM25CF75 was the highest (39.00 µg·g^-¹·h^-¹). Urease activity first increased and then decreased with the increase of organic fertilizer application ratio. The α-D-glucosidase and urease activities of soil in the non-fertilized area were also significantly increased. (3) The combination of organic and inorganic application significantly increased the soil POC/SOC and carbon pool management index (CPMI) of the fertilization area, and the carbon pool management index under CM25CF75, CM50CF50, CM75CF25 and CM100 treatments increased by 19.7%, 38.3%, 56.2% and 103.5%, respectively. The carbon pool management index of organic and inorganic combined application in non-fertilized area decreased significantly. Soil carbon pool management index in fertilized area was significantly higher than that in non-fertilized area under the same treatment. (4) Correlation analysis and principal component analysis showed that there was a significant positive correlation between labile organic carbon components and α-D-glucosidase activity in the soil in the fertilization area, and the increase of organic fertilizer ratio contributed more to the increase of soil labile organic carbon. The effect of fertilization treatment on the fertilized area was greater than that on the non-fertilized area.【Conclusion】 The effect of organic and inorganic combined application on soil improvement in fertilized area of apple orchard was greater than that in non-fertilized area. The combination of organic and inorganic application could increase the content of soil organic carbon and promote soil enzyme activity, which provided a theoretical basis for the sustainable management of soil ecological environment in apple orchard.

Effects of Soluble and Insoluble Dietary Fiber from Shatianyu Pulp on Gut Microbiota

WANG LuLu, ZHANG MingWei, YE JiaMin, ZHANG RuiFen, DENG Mei

Scientia Agricultura Sinica. 2024, 57(20): 4119-4129. doi:10.3864/j.issn.0578-1752.2024.20.016

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【Objective】 The effects of soluble and insoluble dietary fiber (DF) from Shatianyu (Citrus grandis L. Osbeck) pulp on gut microbiota were explored, so as to enrich the theoretical basis of fruits and vegetables DF in regulating gut microbiota, therefore guiding their precision nutrition processing. 【Method】In vitro fecal microbiota fermentation model was used to ferment soluble DF (SDF), insoluble DF (IDF) and total DF (TDF, IDF and SDF mixed according to their proportion in Shatianyu) for 24 h, respectively. The content of SCFAs in each fermentation broth was analyzed by gas chromatography. The structure of fecal microbiota in each fermentation group was analyzed by 16S rRNA sequencing. Microstructure of Shatianyu DF and their microbial attachment status were analyzed by scanning electron microscopy. Pearson correlation analysis was used to analyze the correlation among the relative abundance of bacteria and SCFAs content in fermentation broth.【Result】IDF, SDF and TDF in Shatianyu pulp all improved acetic and propionic acid content in fermentation broth. IDF and TDF group showed higher acetic and propionic acid content than those in SDF group, and IDF also improved butyric acid content. After 24 h-fermentation, IDF and TDF group showed similar microbial community composition on the OTU level, which was obviously different from those of SDF group. Many rod-shaped bacteria gathering in the cracks on SDF surface were observed, however, a large number of spherical or ellipsoidal bacteria gathering in the cracks and folds on IDF surface were found. LEfSe analysis revealed that SDF specifically induced the enrichment of Veillonellaceae, unclassified_k__norank_d__Bacteria and Butyricicoccus, while IDF specifically induced the blooming of Streptococcus, Faecalibacterium, Paraprevotella, Lachnospira, and TDF specifically induced the enri-chment of Prevotella, unclassified_p__Firmicutes, Lactobacillus and Turicibacter. Furthermore, the abundance of characteristic microbes in IDF and TDF group was significantly positively correlated with SCFAs content in fermentation broth.【Conclusion】It was different from the traditional view that IDF mainly played a role in promoting intestinal motility, and Shatianyu pulp IDF was also an important energy source of gut microbiota, which was more effective in regulating gut microbiota producing SCFAs than those of SDF. Thus, Shatianyu pulp IDF was a potential functional ingredient of healthy food for improving intestinal microecology.

Full-Length Transcriptomic Analysis of Chicken Pituitary Reveals Candidate Genes for Testicular Trait

MA JingE, XIONG XinWei, ZHOU Min, WU SiQi, HAN Tian, RAO YouSheng, WANG ZhangFeng, XU JiGuo

Scientia Agricultura Sinica. 2024, 57(20): 4130-4144. doi:10.3864/j.issn.0578-1752.2024.20.017

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【Background】Testis is an important reproductive organ of male animals, which has the function of producing sperm and secreting androgen. The quality of testis is directly related to reproductive performance. Testicular traits are regulated by multiple genes in the hypothalamic-pituitary-gonadal axis, but the molecular mechanism is still unclear. The variation coefficient of testicular traits was large in Ningdu yellow chicken, with poor reproductive performance consistency. 【Objective】 In order to explore candidate genes and key signaling pathways, full-length transcriptome sequencing was performed on pituitary tissues of six individuals with different testicular traits. The selection and breeding of testis traits was expected to develop local chicken breeding with these founding genetic basis.【Method】A total of seventy 22-week-old Ningdu yellow roosters were studied. Six individuals were randomly selected, including three individuals with large testicular and others with small testicular. Full-length transcript expression profile was constructed on pituitary tissue for each individual. Then the genes or transcripts were selected with high expression or different expression between two groups of individuals. Gene function enrichment analysis was also performed for these differentially expressed genes or transcripts. Six genes were randomly selected to verify the gene expression level. Referred to known marker genes in pituitary cells, screening the differentially expressed genes or transcripts were carried out corresponding to the marker genes in the eight kinds of cells. The correlation was analyzed between testicular traits and these genes or transcripts and also those with high expressional level.【Result】In six pituitary tissues, 21 834 genes and 29 355 full-length transcripts were detected. Among them, 332 genes and 229 transcripts were differentially expressed between the two groups. KEGG pathway analysis showed that differentially expressed genes or transcripts were mainly concentrated in apelin signaling pathway, and glycerophospholipid metabolism. Five marker genes of the gonadotropin cell were identified related to part of testicular traits, including NFASC (neurofascin) and its transcript XM_015298904.2, TESC(tescalcin) and its transcript XM_025155510.1, ONT.20974.4 (one transcript of follicle stimulating hormone beta), RLN3 (relaxin 3), ONT.1176.4 (one transcript of NADH: ubiquinone oxidoreductase subunit B2). Four genes were also identified related to part of testicular traits, including EGR1 (early growth response 1) as one of the marker genes in the lactotrophs, TMSB4X (thymosin beta 4, X-linked) and C1H12ORF57(chromosome 1 open reading frame) as the marker genes of the folliculo-stellate cells, CHGB (chromogranin B) as one of the marker genes in the thyrotrophs. Two highly expressed genes were identified related to part of testicular traits, including TMSB4X and HSP90AA1 (heat shock protein 90 alpha family class A member 1). FSHB and EGR1 were found as node genes in the gene interaction network.【Conclusion】Preliminary functional analysis showed that EGR1, TMSB4X, FSHB and RLN3 were the key genes in testicular trait regulation. MAPK, neuroactive ligand-receptor interaction and GnRH signaling pathway played the key role in the regulation of testicular traits.

Effects of Aflatoxin B1 on Influenza Virus Replication, Organ Damages and Intestinal Microbiota Disorder of Swine

ZHAO WenShuo, ZHANG JinLong, YAO ZhaoRan, SONG YuQi, LÜ Shun, LIU YingXue, YUAN CongCong, SUN YuHang

Scientia Agricultura Sinica. 2024, 57(20): 4145-4160. doi:10.3864/j.issn.0578-1752.2024.20.018

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【Background】 Aflatoxin B1 (AFB1) is a secondary metabolite produced by Aspergillus parasiticus, which is widely found in contaminated food and feed all over the world and is considered one of the major risk factors affecting human and animal health. The swine influenza virus (SIV) is currently one of the most widespread viruses in the world, and its replication is susceptible to environmental and nutritional factors. However, the relationship between AFB1 contamination in feed and SIV infection is not clear.【Objective】The objective of this study was to investigate the effects of AFB1 exposure on SIV replication, organs damage and intestinal microbiota, so as to lay a foundation for the study on the mechanism of mycotoxin poisoning, and also provide a reference for exploring the reasons for the increase in susceptibility to other infectious diseases. 【Method】 In this study, thirty-two male piglets were randomly divided into 4 groups (8 piglets in each group), the low-pathogenic SIV virus dilution was inoculated on the first and fourth day of the trial, and established a piglet model of SIV infection (the natural host of SIV). AFB1 was freshly diluted daily and and given 0, 10, 20 and 40 μg·kg^-1 (feed) AFB1 to piglets for 21 days. The piglets were weighed before feeding at 7, 14 and 21 days, respectively, and used a variety of technologies to assess the effects of dietary AFB1 exposure on the weight gain, SIV replication, organs index, autopsy changes, and pathological characteristics, On this basis, the expression of nucleoprotein (NP) of SIV in the lungs were further analyzed by Western blotting and the changes of intestinal microbiota were detected by 16S rRNA, thereby elucidate the effect of AFB1 exposure on SIV infection, organ damage, and intestinal microbiota. 【Result】The results showed that piglets exposed to 40 μg·kg^-1AFB1 had significantly lower weight gain (P<0.01), the expression of NP and lung index of SIV were significantly higher (P<0.01), and the spleen index was significantly lower than those exposed to 0 μg·kg^-1AFB1 (P<0.01); The results of autopsy showed severe spleen, liver and lung damage in piglets exposed to 40 μg·kg^-1 AFB1; HE-stained also showed similar results, compared with the SIV control group, 40 μg·kg^-1AFB1 treatment group showed congestion in the spleen, the red and white pulp were not clear; the liver tissue was hemorrhage, inflammatory cells were infiltrated; the small alveoli of the lungs fused into large alveoli with irregular morphology, the alveolar interstitium was thickened, and the inflammatory cell infiltration was increased; in addition, the intestinal villi were irregularly shaped, the connective tissue was loose, and there was lymphocytic infiltration. The results from 16S rRNA sequencing showed that the exposure to 40 μg·kg^-1 AFB1 significantly increased the relative abundance of Actinomycetota and Clostridium in the intestinal tract of piglets, and decreased the abundance of Lactobacillus and Bacteroidetes. 【Conclusion】Taken together, our results suggest that AFB1 exposure can reduce the body weight gain, promote SIV replication, aggravated the damage of lung tissue and other organs, and cause intestinal microbiota disorders, which provided a theoretical reference for the study of the toxic mechanism of AFB1.

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