Abstract:This paper proposed a method for detecting apple at night based on YOLOv8n with fusion of image enhancement and transfer learning to address the issues of low recognition rate and poor real-time performance of apples in nighttime scenarios. Firstly， embedding a Zero-DCE module in the front-end of YOLOv8n enhanced images of apple at night， presented the contours and details of apples more clearly， and reduced the difficulty of recognizing images of apple at night. Secondly， using SPD-Conv for down-sampling enhanced the ability of the model to extract fine-grained features. On this basis， transfer learning training strategy was used to solve the problem of small sample size in the dataset of apple at night. The MS COCO dataset containing categories of apple was selected as the source domain dataset. In term of the target domain dataset in nighttime scenarios， Zero-DCE was used to increase its similarity with images of apple during the day and finely tune the model of target domain on the model of source domain. Experiments were conducted on the image dataset of apple at night based on the method above. The results showed that the model accuracy P， a recall R， and an average accuracy mean mAP@0.5：0.95 of method proposed was 97.0%，93.4% and 74.6%， being 2.3，1.9， and 4.3 percentages higher than that of the YOLOv8n original model. The inference speed of this model was 22 frames/s， meeting requirements of real-time detection. The results of the ablation experiment showed that the combined effect of image enhancement and transfer learning exceeded the sum of the effects when applied separately. The improved model performed better than the original model in dealing with complex situations including overlap， occlusion， green fruits， and dim lighting， and had good robustness.

Abstract:A real-time object detection method of pineapple ripeness based on improved YOLOv8 was proposed to improve the accuracy of mechanical harvesting of pineapples in planting areas with different ripeness and ensure the quality of pineapples. The improved model replaced the common convolutions in the backbone and neck parts of the original YOLOv8 model with depth-wise separable convolutions （DSConv） to streamline parameters of model to solve the problems of small object size， dense quantity， and light occlusion of picked mechanical pineapple picking in natural environments. Convolutional block attention mechanism （CBAM） module was introduced before feature fusion to prioritize important features and improve the accuracy of object detection. The original loss function CIoU of YOLOv8 network was replaced with the EIoU loss function to accelerate the speed of network convergence. The results showed that the mean of average precision （P_mA） of the improved model for detecting the pineapple ripeness was 97.33%. The P_mA of improved model was 5.53， 7.91， 4.38， and 4.66 percentage points higher than that of Faster R-CNN， YOLOv4， YOLOv5 and YOLOv7， respectively. The number of parameters of the algorithm model was only 16.8×10⁶ on the premise of ensuring the accuracy of detection. It is indicated that the improved model improves the accuracy and inference speed of recognizing pineapple ripeness， and has stronger robustness.

Abstract:The pineapple （Ananas comosus （L.） Merr.） picker with integrated clip needs to independently determine the cutting points in fruit stem of pineapple when picking in the field. Pineapple stems are easily obstructed by plant leaves and bracts， making it difficult to accurately identify the cutting points in fruit stem with a single method of image processing. A method for detecting the cutting points in fruit stem of pineapple based on the fusion of multi-sensor information was proposed. The length from the top of the pineapple crown bud to the bottom of the fruit was measured by combining a depth camera with multiple sets of photoelectric sensors and utilizing an improved YOLOv5 object detection algorithm to fuse RGB-D depth information. The changes in signal of photoelectric sensor were used to determine whether the pineapple picker has reached the top position of the crown bud. The top of the crown bud was used as the starting position to control the descent speed and time of the picker to ensure that the cutting blade installed at the bottom of the picker accurately reaches the cutting point of the fruit stem. The results of bench test showed that this method had a success rate of 85% in detecting the cutting points in real fruit stem of pineapple， meeting the accuracy requirements of detecting the cutting points in fruit stem of pineapple during the operation of pineapple picking robots. It will be of great significance for realizing the intelligent pineapple picking， and will lay a foundation for the subsequent development of pineapple picking robots in the field.

Abstract:This article proposed an improved YOLOv5s model to improve the accuracy of detecting plums （Prunus salicina Lindl.） with high occlusion and density in orchards and the lightweight. Firstly， a new Focus-Maxpool module was used to replace the down-sampling convolution in the backbone network， enabling the model to retain more feature information of small and highly occluded targets during down-sampling. Secondly， the weighted loss of focal loss and cross-entropy function was used as the classification loss of the model to improve its recognition ability for adhesive targets. Finally， several sets of detection experiments were designed to evaluate the performance of the model. The results showed that the average accuracy of the improved YOLOv5s model was better than that of YOLOv5s，YOLOv4，Faster RCNN，SSD，and Centernet. Compared with the detection results of the YOLOv5s model， the average accuracy， recall rate， and accuracy of the improved model increased by 2.84，9.53，and 1.66 percentages， respectively. The detection speed of the improved model reached 91.37 frames per second， meeting the requirements of real-time detection. It is indicated that the model improved has higher accuracy of detection and robustness in real orchard environments. It will provide data reference for studying fruit-picking robots and monitoring orchard environments.

Abstract:A improved Faster RCNN algorithm was proposed to solve the difficulties of identifying tea leaf diseases under the complex background of tea gardens. VGG-16 and MobileNetV2 networks were extracted by the features of optimized regional recommendation boxes and compared with ResNet50 network. ResNet50 with good performance of identification was selected as the backbone network to enhance the model's ability to extract features of tea leaf diseases under the complex background of tea gardens. The feature pyramid network （FPN） was integrated to improve the problem of missing detection of small targets and multi-scale lesions. The Rank and Sort （RS） Loss function was used to replace the loss function in the original Faster RCNN， which alleviated the impact of uneven sample distribution on the performance of model and further improved the accuracy of identification. The results showed that the mean average precision P_mA and the identification speed of the model improved was 88.06% and 19.1 frames/s. The average precision value of identifying algal spot， white scab， anthracnose and sooty mold was 75.54%， 86.84%， 90.42% and 99.45%， respectively. The average precision value of identifying with improved Faster RCNN algorithm was 40.98， 44.16， 13.9 and 2.43 percentages points higher than that with Faster RCNN algorithm. It is indicated that the method for identifying leaf diseases of tea based on the improved Faster RCNN algorithm can weaken the interference of complex background of tea garden and accurately identify leaf disease target of tea under the complex background of tea garden.

Abstract:Rapeseed is the second largest oil crop in the world and the most important source of edible vegetable oil in China. Rapeseed breeders have attempted to breed elite varieties through traditional breeding schemes for a long time. However， Brassica napus L. is an allotetraploid species that evolved from double diploidization after interspecific hybridization， and there is a significant amount of gene redundancy in its genome. Therefore， the efficiency of improving traits through traditional genetic methods including artificial hybridization selection and random mutagenesis is very low. In recent years， CRISPR/Cas9 technology has been widely used in studying gene function and targeted genetic improvement of polyploid rapeseed due to its unique advantages of high efficiency and simplicity. It is timely to apply CRISPR/Cas9 gene editing technology to Brassica napus L. for the rapid and efficient innovation of germplasm resource and genetic improvement. This article reviewed the progress towards the application of CRISPR/Cas9 system in studying gene function and genetic improvement of rapeseed， involving important agronomic traits such as yield， the content of oil， the composition of fatty acid， the tolerance of biological and abiotic stress. The limitations of gene editing in rapeseed and the directions for future development were discussed as well.

Abstract:183 maize inbred lines were planted in Guiyang according to a random block design to preliminarily study the genetic patterns of the content of crude protein， starch， neutral detergent fiber （NDF）， acid detergent fiber （ADF）， soluble sugar， and the in vitro digestibility of dry matter in maize. The content of crude protein， starch， NDF， ADF， soluble sugars， and the in vitro digestibility of dry matter in maize was determined. The Maize SNP 50 chip was used to genotype materials tested. Genome-wide association analysis （GWAS） with the mixed linear model （MLM） was performed. The results showed that 31， 61， 11， 36， 20， and 42 single nucleotide polymorphisms （SNPs） sites were identified to be significantly associated with the content of crude protein， starch， NDF， ADF， soluble sugars， and the in vitro digestibility of dry matter in maize （P<0.001）， with the explanation rates for phenotypic variation of 5.80%-11.40%，5.78%-11.38%，5.78%-7.85%，5.81%-10.37%，5.78%-7.35%，and 5.79%-11.33%， respectively. It was found that SYN6712， PHM1190.3， SYN7541， and PZE-104072386 belong to a pleiotropic locus. Among them， SYN6712， PHM1190.3， and SYN7541 on the chromosome 6 were significantly associated with the content of starch and the in vitro digestibility of dry matter， while PZE-104072386 on the chromosome 4 was significantly associated with the content of ADF and soluble sugars. The results of allele identification showed that the T/T genotype was an elite allele of SYN6712 and PHM1190.3， and candidate genes including Zm00001d03772， Zm00001d037386， Zm00001d037532， and Zm00001d051166 were identified. It will provide theoretical support for the further studies on the genetic mechanism of quality related traits in maize including the content of crude protein， starch， NDF， ADF and soluble sugars， as well as for the molecular markers assisted breeding.

Abstract:333 accessions of Saccharum spontaneum L. from Guangxi were used to mine the excellent wild genetic resources for sugarcane breeding. The data from 12 pairs of SSR primers and 28 phenotypic traits were used to construct the core germplasm and conduct association analysis of Saccharum spontaneum L. in Guangxi. The results of association analysis showed that 5 phenotypic traits including the stem diameter， the internode length， the color before exposure， defoliation and hairiness were significantly correlated with 8 SSR loci. The diameter of stem was significantly correlated with leaf length， leaf width， internode length， number of nodes and brix. There was a significant to extremely significant positive correlation between the 4 phenotypic traits including the plant height， stem diameter， internode length， and number of nodes. The brix was negatively correlated with stem diameter and internode length. Core germplasm sampling was subjected to gradient screening based on the proportion of total resources at 0.1， 0.2， 0.3， 0.4， 0.5， 0.6， 0.7， 0.8， and 0.9. When the sampling ratio reached 30% or more， it covered 100% allele. The results of evaluating genetic diversity and principal component analysis showed that the screened materials for constructing the core germplasm of Saccharum spontaneum L. had rich genetic diversity， and the principal component map drawn based on the core germplasm was consistent with the distribution map of the original germplasm. It is indicated that the core germplasm of Saccharum spontaneum L. constructed with 99 selected samples based on a sampling ratio of 30% has good representativeness by evaluating genetic diversity and principal component analysis.

Abstract:Diallyl disulfide （DADS） is a biologically active organic sulfide produced by the decomposition of allicin， which has a strong effect on inhibiting plant stress. The Chinese cabbage variety ‘Golden Kirin’ was used to study the effect of DADS on mitigating the autotoxicity of Chinese cabbage. 6 groups of treatments including CK1（1/2 Hoagland nutrient solution）， CK2（continuous cropping solution）， D1 （1 μmol/L DADS + continuous cropping solution）， D5 （5 μmol/L DADS + continuous cropping solution）， D10 （10 μmol/L DADS + continuous cropping solution）， D15 （15 μmol/L DADS + continuous cropping solution） were set up using hydroponic experiment， with 12 tissue culture bottles in each treatment and 4 seedlings cultured in each bottle. The effects of different concentrations of DADS on the growth， physiological and biochemical trait of seedlings under the autotoxicity of Chinese cabbage were investigated. The results showed that the application of different concentrations of DADS had an effect on promoting the growth of seedlings under the autotoxicity of Chinese cabbage， with D5 having the best effect of mitigating. Compared with CK2， D5 treatment significantly increased the fresh weight of aboveground and underground parts of seedlings， and root activity of Chinese cabbage by 19.42% and 23.40%， and 45.29%. The length of total root and the number of root tip increased as well， which mitigated the damage of autotoxicity effect on root structure； meanwhile， the content of chlorophyll in leaves was increased， which promoted the photosynthesis in turn. The content of osmoregulatory substances in seedlings of Chinese cabbage significantly increased， with the activity of antioxidant enzyme SOD， POD， and CAT increasing by 30.75%， 27.44%， and 17.68%， and the content of MDA significantly decreasing by 20.58%. The results of histological staining showed that the accumulation of hydrogen peroxide anion and superoxide anion was significantly reduced by D5 treatment. It is indicated that exogenous application of diallyl disulfide （DADS） can effectively mitigate the autotoxicity of exudates from the roots of Chinese cabbage by reducing the oxidative stress and promoting the growth of root. The most significant mitigating effect was observed when 5 μmol/L DADS was applied. It will provide a new method to mitigate the obstacles of continuous cropping caused by the autotoxicity and lay the foundation for the rational use of diallyl disulfide （DADS）.

Abstract:‘Dongshi Zaoyou’ pummelo and its hybrid offsprings，methods including magenta acetate staining and aniline blue staining，cross-pollination，and molecular markers were used to study the mechanism of seedlessness in ‘Dongshi Zaoyou’ pummelo.The results showed that the floral structure of ‘Dongshi Zaoyou’ pummelo was intact，with pollen vitality and germination rates of 94.80% and 86.20%，respectively.The self-pollination of ‘Dongshi Zaoyou’ pummelo showed incompatibility，while cross-pollination with ‘Shatianyou’ pummelo showed compatibility.A total of 164 F₁ hybrids were identified from 175 hybrid offsprings of ‘Shatianyou’ pummelo × ‘Dongshi Zaoyou’ pummelo with S₅/S₆ molecular marker genotyping，ruling out the possibility of male sterility in ‘Dongshi Zaoyou’ pummelo.The results of observation for two consecutive years showed that the mean fruit setting rates of stimulating parthenocarpy and natural parthenocarpy in ‘Dongshi Zaoyou’ pummelo was 13.04% and 25.56%，respectively.It is indicated that the main reason for the seedless development of ‘Dongshi Zaoyou’ pummelo is its self-incompatibility and certain ability to produce parthenocarpy.

Abstract:The pot flooding method was used to study the waterlogging tolerance of grapevine to mine and utilize the plant rhizobacteria and their functions. Cuttings of 1-year-old Kyoho grapevine were subjected to flooding stress for 21 days and recovery for 7 days after flooding. 16S rRNA high-throughput sequencing technology was used to sequence bacteria in soil， analyze the composition and structure of bacterial community， and study the effects of flooding stress on the composition of rhizobacteria community in Kyoho grapevine. The results showed that the abundance of rhizobacteria in Kyoho grapevine was the highest after 21 days of flooding， and the diversity of rhizobacteria in Kyoho grapevine was the highest after 14 days of flooding. The relative abundance of Thiobacillus increased significantly during the recovery period after stress. The results of functional prediction of root bacteria showed that there were significant changes in the metabolism of lipid， terpenoid and polyketide. It is indicated that short-term flooding stress promotes the production of metabolites in plants to change bacterial communities in response to stress， but prolonged flooding disrupts plant metabolism， leading to an increase in the abundance of potentially harmful bacterial flora and a decrease in beneficial bacterial flora in plants. It will provide theoretical basis for the mining and utilization of rhizobacteria and their functions.

Abstract:Chiral nanomaterials are a class of emerging materials with nanoscale chirality and biological stability， which have attracted widespread attention from researchers in fields including pharmacology， biology， and drug development. The methods of synthesizing chiral nanomaterials mainly include three types： chiral ligand mediated， self-assembly， and external field induction. Compared with chiral materials in nature， chiral nanomaterials synthesized exhibit unique optical properties including plasmonic circular dichroism， photonic circular dichroism， and effects of circularly polarized luminescence， which are mainly characterized by circular dichroism spectroscopy and circularly polarized luminescence spectroscopy. Based on these unique optical properties of chiral nanomaterials， researchers have studied the effects of chiral nanomaterials on cells. Chiral nanomaterials with selective antibacterial effects on gram-negative bacteria， Escherichia coli and Staphylococcus aureus， and selective antiviral effects on hepatitis B virus， tobacco mosaic virus and the reproductive and respiratory syndrome virus in porcine have successively been developed. This article briefly introduced the methods of synthesis， optical properties， and characterization of chiral nanomaterials. The effects of chiral nanomaterials on cells and the progress on studying the antibacterial and antiviral properties of chiral nanomaterials were systematically summarized. A summary and outlook were made on the current problems and future directions of developing chiral nanomaterials.

Abstract:The reduction of chemical fertilizer combined with applying biochar and straw is an effective way of realizing the green and sustainable development of agriculture in China. A field plot experiment was conducted to study the efficient management of nutrient resources and the utilization of straw resources in the lime concretion black soil areas. The effects of reducing chemical fertilizers combined with returning straw to the field and biochar on the yield of rice， nutrient absorption and carbon in soil in the region were investigated for 2 consecutive years. 5 treatments including no fertilizer （CK）， conventional application of chemical fertilizer （100% NPK）， 20% reduction of chemical fertilizer （80% NPK）， 20% reduction of chemical fertilizer plus straw returning （80% NPK+S）， 20% reduction of chemical fertilizer plus biochar （80% NPK+B） were set up. The yield and biomass aboveground of rice， the content of N， P and K in plant， the content of total organic carbon （TOC） and microbial biomass carbon （MBC） in soil were measured and analyzed. The results showed that 80% NPK+S or 80% NPK+B was beneficial for increasing the yield and biomass aboveground of rice， with the effect of 80% NPK+B more significant than that of 80% NPK+S. The average yield and biomass aboveground of rice treated with 80% NPK+B was 5.2% and 4.7% higher than that with 100% NPK， and by 7.9% and 7.2% higher than that with 80% NPK， respectively. The average yield and biomass aboveground of rice treated with 80% NPK+S was 3.4% and 3.0% higher than that with 100% NPK， respectively. There was no significant difference in the average yield and biomass aboveground of rice between the 80% NPK treatment and the 100% NPK treatment. The accumulation of N， P₂O₅， and K₂O nutrients in the aboveground parts of rice treated with 80% NPK+B significantly increased， 10.4%， 7.2%， and 20.0% higher than that with 100% NPK. 80% NPK+S treatment significantly increased the accumulation of nitrogen and potassium in rice， but significantly reduced the accumulation of phosphorus in rice at the same time. 80% NPK+B treatment or 80% NPK+S treatment was beneficial for improving the accumulation of total organic carbon in soil and significantly increasing the content of microbial biomass carbon in soil. Among them， the effect of biochar on increasing the content of total organic carbon in soil was better than that of straw， while the effect of straw on increasing the content of microbial biomass carbon in soil was better than that of biochar. Overall， 80% NPK+B treatment or 80% NPK+S treatment can increase or maintain the yield of rice， improve nutrient absorption capacity of rice， and facilitate the fixation of organic carbon in soil in the lime concretion black soil areas along the Huai River.

Abstract:Two types of cadmium （Cd） contaminated soils in Xichuan County，Henan Province were collected to study the feasibility of using bio-organic fertilizers to treat cadmium contaminated soils and the effectiveness of remediating heavy metal pollution in soil.6 treatments of fertilization including CK （without applying any materials），NPK （conventional application of NPK fertilizer），NPK+0.5% OF （conventional fertilization + 0.5% commercial organic fertilizer），NPK+1% OF （NPK + 1% commercial organic fertilizer），NPK+0.5% BF （NPK + 0.5% bio-organic fertilizer），and NPK+1% BF （NPK + 1% bio-organic fertilizer） were set up.The content of total cadmium in the soil，the chemical forms of cadmium in the soil，and the content of cadmium in the roots and seeds of maize were measured before and after planting.The results showed that the effect of NPK+1% BF was the best，and the content of available cadmium in two types of soil under NPK+1% BF decreased by 19.74% and 7.09% compared to that under NPK+1% OF.The application of organic materials reduced the content of cadmium in the weakly acid-extractable state in soil and increased the content of cadmium in the residual state.The content of cadmium in the weakly acid-extractable state in soil under NPK+1.0% BF decreased by 11% compared to that under CK，while the content of cadmium in the residual state increased by 16%.The application of organic materials significantly reduced the content of cadmium in the roots and seeds of maize，with the NPK+1.0% BF having the best effect.Compared with NPK treatment，the content of cadmium in roots and seeds of maize in soil I decreased by 34.41% and 31.59%，respectively.It is indicated that applying bio-organic fertilizers in cadmium contaminated soil can significantly reduce the content of available cadmium in the soil，promote the transformation of cadmium in the weakly acid-extractable state to cadmium in the residual state，and reduce the hazards of cadmium.The content of cadmium in roots and seeds of maize significantly decreases，and bio-organic fertilizer is superior to commercial organic fertilizer in terms of the comprehensive effect.

Abstract:Wuhan City was used to accurately evaluate the differentiation characteristics of canopy heat island intensity in highly complex megacity. A calculation method for canopy urban heat island intensity （CUHII） considering spatial differences in different urban areas was proposed. The characteristics of urban heat islands under different algorithms were studied with combining traditional algorithms based on the “urban suburban” dichotomy. Results showed that each area consistently exhibited urban heat island phenomenon under traditional algorithms， and the daily variation curve of CUHII was highly consistent. On the contrary， there was a significant difference in the daily variation of CUHII among different areas in the regional algorithm， and the Wuchang district with multiple large ecological spaces exhibited a sustained cold island phenomenon during the daytime. In addition， traditional algorithms identified cold and heat island centers that are relatively small and distributed around the periphery of the central urban area， while regional algorithms identified heat island centers that cover high-density development areas in the middle of the urban area in a belt shape， and the cold island centers are adjacent to large natural lakes in the Wuchang district. It is indicated that the algorithm proposed weakens the interference of uneven development of urban areas on the assessment of canopy heat island， which is conducive to in-depth mining of heat island characteristics and more accurate identification of areas that need priority intervention in urban thermal environment.

Abstract:The indicators for discriminating low-temperature and persistent rain at different growth stages of flue-cured tobacco were established to better defense against the adverse effects of low temperature and persistent rain disasters on the yield and quality of flue-cured tobacco in Hubei Province. The data of daily meteorology from 32 national meteorological observation stations in the tobacco planting areas of Hubei Province from 1975 to 2020 were used to in depth analyze the spatiotemporal distribution characteristics of seven disaster indicators related to the low temperature and persistent rain in the tobacco planting areas of Hubei Province. The results showed that three indicators including the average temperature during the process， the average daily precipitation， and the average total precipitation all followed an evolutionary pattern of low-high-low in terms of time， with the highest at the early stage of maturity and the lowest at the stage of root extension. The average number of days in the process was about 5 days. The average annual number of processes， the average annual days of process， and the frequency of disasters were the highest at the late stage of maturity and the lowest at the stage of vigorous growth. Among them， the frequency of disasters occurred 6 and 1 times every 10 years at these two stages， with a difference of nearly 6 times. In terms of space， there were consistent differences in temperature and precipitation between the north and south at different stages of growth. The tobacco growing areas in the northern had lower temperatures， while the tobacco growing areas in the southern had more precipitation with higher intensity. The average days of the process in the southern part was longer than that in the northern part at the stage of root extension and vigorous growth， while the opposite was true at the late stage of maturity. There was a significant spatial difference in the frequency of disasters. The frequency of disasters at the first three stage of growth in tobacco growing areas in the southern was higher than that in tobacco growing areas in the northern. The frequency of disasters at the late stage of maturity was equivalent to that in tobacco growing areas in the north and south， with an average duration of over 56% and an average duration of 5.7 days. It will provide a scientific basis for the planning of tobacco cultivation in Hubei and the defense against disasters of low-temperature and persistent rain.

Abstract:Breast cancer is one of the three most common cancers with the highest mortality rate in the world and poses a serious threat to human health.MicroRNA （miRNA），as a small molecule of gene regulation，can mediate cellular target genes to regulate the occurrence and development of breast cancer.In this paper，we classified miRNA according to their sources，reviewed the currently known functional properties of endogenous and exogenous miRNA （botanmin），and explored their regulatory mechanisms in breast cancer.At the same time，the potential targets of exogenous miRNA associated with breast cancer were predicted by bioinformatics，which provided a reference for their application in breast cancer therapy.

Abstract:Pig industry is an important component of animal husbandry industry in China.The domestic pig production mainly adopts self-breeding mode.The semen used in pig reproduction is usually fresh semen or diluted at room temperature， while semen cryopreservation technology can realize the long-term preservation of pig semen.Compared with cattle， mice and other species， the cryopreservation technology of pig semen needs to be further optimized and improved.In order to provide a theoretical reference for perfecting the freezing technique of pig semen and accelerating its large-scale application in pig production，this review summarized the development and main technological process of freezing and thawing of porcine semen， and the key factors affecting sperm motility after freezing and thawing， including semen collection， pre-cooling balance before freezing， addition of cryoprotectant agents， and cryopreservation methods.It also covered the physicochemical changes during the sperm cryopreservation process， such as physical structural damage， functional damage， and sperm anti-freezing mechanisms.Finally， the new methods to improve the cryopreservation efficiency of pig sperm were summarized and prospected， including nanotechnology treatment of semen and the study of cryopreservation biomarkers for sperm.

Abstract:The hardware facilities and technical methods related to non-contact measurement of pig body size have undergone significant changes with the advancement of technology in fields including visual sensors and computer vision.Visual perception needs to meet three-dimensional requirements，and corresponding equipment have been updated from black and white cameras to depth equipment.The types of equipment usually determine the basic implementation plan and technical methods，however，current studies in this field mostly focus on specific algorithm details，which is difficult to meet the requirements of practical engineering.This article focused on the types of visual sensors and outlined different engineering deployment solutions for non-contact measurement of pig body size.The methods of equipment use and the environment and methods of data collection were summarized.The five tasks of 3D point cloud technology in measuring pig body size were analyzed.The advantages，disadvantages and potential for improvement of current studies and solutions for combination with applications of practical engineering were reviewed.The difficulties in studies on combining deep learning with 3D point cloud technology were prospected.The results of comparison showed that depth equipment and 3D point cloud technology are the directions for future applications of engineering in this field.Deep learning-based point cloud segmentation，point cloud completion，key point detection and other technologies have good prospects of application.It will provide a reference for the subsequent studies on non-contact measurement of pig body size.

Abstract:Pseudorabies is an acute infectious disease of pigs, which is caused by the infection of pseudorabies virus(PRV). Pseudorabies is mainly prevented by vaccine, and PRV gene-deleted vaccine is the most widely used and effective. Since 2011, a new outbreak has occurred in many pig farms vaccinated with the Bartha-K61 vaccine and has spread to farms in most parts of the country, causing enormous economic losses to the development of our farms. The study found that the new outbreak was caused by PRV variants and showed that the commercially vaccine did not provide complete protection. Therefore, it is urgent to develop a new and efficient PRV vaccine.The prevalent strain JS18 of porcine pseudorabies virus was passaged with chicken embryo fibroblast （CEF） cells to obtain the attenuated vaccine with good safety and high immunogenicity for mutated strain of porcine pseudorabies virus. JS18-150 strain was obtained. Preliminary studies were conducted on the in vitro growth characteristics， safety， and immunogenicity of JS18-150 strain through PCR identification， sequencing， pathogenicity testing， and immunogenicity testing. The results showed that the gI， gE， and US9 genes of JS18 strain were deleted and the virulence of JS18-150 strain obtained was weakened after continuous passage on CEF. The adaptability on CEF of JS18-150 strain obtained was significantly improved. The growth kinetics of JS18-150 strain obtained was similar to that of the original JS18 strain. No clinical symptoms were observed in all piglets inoculated with 10^7.0 TCID₅₀ JS18-150 strain obtained， and the rectal temperature did not exceed 40.5 ℃. Inoculation with 10^6.0 TCID₅₀ JS18-150 strain obtained effectively protected piglets from the attacks of JS18 strain and HBZL05 strain. It is indicated that JS18-150 strain obtained has good safety for piglets and can be used as a candidate strain for the development of attenuated PRV vaccines.

Abstract:To investigate the changes of vascular endothelial barrier during exudative inflammation caused by Haemophilus parasuis （HPS） in pigs，primary pig vascular endothelial cells were infected with HPS.The effects on the expression of the Wnt/β-catenin pathway and its downstream target genes were detected by Western blot and fluorescence quantitative PCR，and the alterations in the structure of intercellular adhesion junctions were detected by indirect immunofluorescence and transendothelial electrical resistance assay.The results showed that HPS infection activated Wnt/β-catenin pathway in porcine endothelial cells，and induced nuclear translocation of β-catenin protein in the cytoplasm，resulting in the destruction of the adhesive junction structure composed of β-catenin and VE-cadherin at the cell membrane and the increase of cell permeability.Moreover，inhibition of the expression of VEGF gene downstream of Wnt/β- catenin pathway significantly suppressed the nuclear translocation of β-catenin and markedly restored the intercellular adherens junctions composed of β-catenin and VE-cadherin，which benefits the recovery of endothelial cell permeability.These results suggested that HPS infection disrupted intercellular adherens junctions and increased endothelial cell permeability by activating the Wnt/β-catenin pathway in porcine endothelial cells； meanwhile，the VEGF gene downstream of the Wnt/β-catenin pathway amplifies the Wnt/β- catenin pathway activity and cell damage induced by HPS infection through a positive feedback.

Abstract:The effects of tyrosine on the formation of melanin in Guyuan silky fowls were studied to investigate the characteristics of the distribution and deposition of melanin in Guyuan silky fowls， and the changes in the expression of melanin-related gene under different content of tyrosine in diet. 150 healthy Guyuan silky fowls at 4 weeks of age with no significant difference in body weight were randomly divided into 5 groups， with 3 replicates in each group and 10 chickens in each replicate. The content of tyrosine added in diet was 0， 0.2%， 0.4%， 0.6%， and 0.8%， respectively， and the fowls were fed until the end of 12 weeks of age. The electron microscopy was used to observe the characteristics of the distribution of melanin in different tissues of Guyuan silky fowls. The immunohistochemistry and fluorescence quantitative PCR method were used to detect changes in the expression of melanin-related genes in different tissues of Guyuan silky fowls. The results showed that there were melanocytes in the skin， trachea， and small intestine of Guyuan silky fowls， and most of them were differentiated and matured. TYR had a positive reaction in lung tissue， TYRP1 had a positive reaction in muscle and liver tissue， and MITF and CREB1 had positive results in lung， liver， small intestine， and breast muscle tissue. The expression level of MITF， TYR， and TYRP1 gene was linearly correlated with the content of melanin under different content of tyrosine in diet. It is indicated that the characteristics of melanin deposition in tissues of Guyuan silky fowls are related to the amount of melanin granules synthesized in the tissues， and TYR and MITF may be the main key regulatory genes during the synthesis of melanin. Adding tyrosine to the diet can promote the expression of melanin-related genes.

Abstract:To study the role of lipin1 （lpin1） gene in the repair of muscle injury in fish， taking Megalobrama amblycephala as the research object， in this study， the temporal and spatial expression of lpin1 gene and its expression change after muscle injury were detected by fluorescent quantitative PCR （qPCR） and whole embryo in situ hybridization （WISH）. The results showed that the ORF sequence of the M. amblycephala lpin1 gene was 2 694 bp， encoding 897 amino acids. Functional domain analysis showed that the Lpin1 protein had highly conserved Lipin-N， Lipin-mid and LNS2 （Lipin/Ned1/Smp2） domains. Phylogenetic analysis revealed that the M. amblycephala Lpin1 was closely related to those of Cyprinus carpio and Danio rerio. The results of qPCR showed that lpin1 was expressed at all stages during the embryonic development of M. amblycephala， and the expression level was the highest in the muscle of adult M. amblycephala. The results of WISH further revealed that lpin1 was specifically expressed in the head and body segments during muscle functioning stage and heartbeating stage. Compared with the uninjured group， the lpin1 expression was the highest at 48 h after mild injury and 216 h after severe injury， respectively， while the pax7 expression was the highest at 144 h after mild injury and 96 h after severe injury， respectively. The above results indicated that lpin1 gene may play an important role in muscle injury and repair of M. amblycephala.

Abstract:In order to screen Bacillus strains which are beneficial to largemouth bass， the Bacillus strains from the intestine of largemouth bass were isolated， their hemolysis， enzymatic activity， biofilm formation ability， sensitivity to various common antibiotics， tolerance to gastric and intestinal fluids， and in vitro antagonism against Nocardia were detected.These strains were added to the feed of largemouth bass and weigh gain and expression of inflammatory cytokine were detected.A total of 94 Bacillus strains were identified.Four Bacillus subtilis strains， K-3， K-12， K-13， and K-22， were selected based on their non-hemolytic and broad enzymatic activity.These four strains all formed strong biofilms and were sensitive to various common antibiotics.Strains K-3 and K-13 showed in vitro antagonism against Nocardia.The 2-hour survival rates of the four strains in artificial gastric and intestinal fluids were above 80%.After feeding for 42 days， the weight gain of largemouth bass of K-13 group was significantly higher than that of the control group， while protease and lipase activities in the intestines in K-12 and K-13 groups were significantly higher than that of the control group. In addition， compared with the control group， the expression levels of pro-inflammatory factors in the head kidney， spleen， and hind gut of the K-13 experimental group were down-regulated， while the expression levels of anti-inflammatory factor were up-regulated， indicating that K-13 has the potential to reduce intestinal inflammation in largemouth bass. Overall， the B. subtilis strain K-13 selected in this study has high safety， broad enzymatic activity， antagonism against Nocardia， and promotes the growth of largemouth bass， making it a potential probiotic additive for largemouth bass feed.

Abstract:A inflammatory model of RAW264.7 cell induced with lipopolysaccharide （LPS） was established in vitro to study the effects and mechanism of baicalin （BCN） against LPS-induced inflammatory injury in mice. The cellular phagocytic ability， nitric oxide （NO） release， and mRNA expression to inflammatory cytokines and TGF-β/SMAD2 pathways related genes were measured. Experiments in vivo were conducted using different concentrations of baicalin to establish an inflammatory model in BALB/c mice after 7 consecutive days of gastric lavage and intraperitoneal injection of LPS. The spleen index， subgroups and immune balance of T cell in mice were detected. RT-qPCR was used to determine the mRNA expression of inflammatory cytokines and TGF-β/SMAD2 pathways related genes in the spleen. Results showed that baicalin had no effect on inhibiting the proliferation of RAW264.7 cell within the range of 0-25 μg/mL. When the LPS concentration was 1 mg/mL， the survival rate of RAW264.7 cell was 54.55%. Different concentrations of baicalin enhanced the phagocytic ability（P<0.05） and reduced NO release （P<0.05） of RAW264.7 cells. The mRNA expression of inflammatory cytokines related genes increased （P<0.05） while the mRNA expression of TGF-β/SMAD2 pathways related genes decreased after LPS stimulation. The mRNA expression of above genes was reversed after intervention with baicalin. The spleen index of mice significantly increased（P<0.05） after LPS treatment， and different doses of baicalin groups improved this situation（P<0.05）. Results of flow cytometry showed that baicalin improved the differentiation of CD4⁺ and CD8⁺ cells stimulated by LPS， reduced the ratio of CD4⁺/CD8⁺， and restored the imbalance of Th17/Treg balance axis induced by LPS. It is indicated that baicalin alleviates the LPS induced inflammation in mice， and its mechanism may be related to the activation of TGF-β/SMAD2 signaling pathway， the inhibition of inflammatory cytokines expression， and the restoration of Th17/Treg balance axis.

Abstract:Four different pre-treatment methods including ultrasound （US）， ultrasound assisted enzymatic method （US+EM）， ultrasound assisted alkaline method （US+AM）， and ultrasound assisted hot-water method （US+WM） were used to study the effects of different desugaring pretreatment on the quality of red jujube crisps dried with hot air drying and instant controlled pressure drop.The color， texture， taste， and the content of main nutrients in the dried red jujube crisps were analyzed.The results showed that different ultrasound assisted desugaring pretreatment had a significant impact on the quality of red jujube crisps dried with hot air drying and instant controlled pressure drop.Compared with different desugaring pretreatment， the solid reduction rate of fresh jujube samples treated with US and US+EM was 2.53% and 3.36%， significantly lower than that with US+AM and US+WM.The content of polysaccharide in US+WM was the lowest with the best effect of desugaring， followed by US+EM treatment with hot air drying and instant controlled pressure drop of red jujube crisps.The US+EM with instant controlled pressure drop of red jujube crisps resulted in a high retention rate of flavonoid and the smallest loss of VC content.The results of electronic tongue showed that the taste of red jujube crisps pretreated with US+EM and dried with instant controlled pressure drop was best.It is indicated that ultrasound assisted enzymatic （US+EM） treatment reduces the content of sugar while retain the flavor and nutrients of red jujube crisps to the greatest extent.

Abstract:The peanut variety “Huayu 23” was used to study the effects of cold soaking temperature， cold soaking time， hot soaking temperature， and hot soaking time on the removal rate， damage rate， and moisture of peanut kernels to improve the quality of wet peeling of peanut kernels. The results showed that factors including cold soaking temperature， cold soaking time， hot soaking temperature， and hot soaking time had a significant impact on the removal rate， damage rate， and moisture of peanut kernels determined by the single factor experiment. It was found by the response surface test that the influencing degree of cold soaking temperature， cold soaking time， hot soaking temperature， and hot soaking time on the removal rate， the damage rate， and the moisture was in the order of cold soaking temperature>hot soaking temperature>hot soaking time>cold soaking time， hot soaking temperature>cold soaking temperature>hot soaking time>cold soaking time， and cold soaking temperature>hot soaking temperature>hot soaking time>cold soaking time. The parameters of pretreatment optimized with Design Expert V13 software were cold soaking temperature of 19 ℃， cold soaking time of 13 min， hot soaking temperature of 75 ℃， and hot soaking time of 20 s. The removal rate， damage rate，and moisture under the optimized parameters was 95.7%，11.3%，and 13.6%， with errors of 1.03%，4.13%，and 0.60% compared to the results of experimental verification. It is indicated that the optimization is reliable.

Abstract:In order to explore the application prospect of phage-derived peptide in food processing chain， SEYT4， a novel phage-derived peptide containing 37 amino acids was selected as the research object and its structural characteristics were analyzed. The common pathogenic bacteria in food processing chain were selected to carry out bactericidal tests under different temperature， salinity and pH to determine the bactericidal spectrum， bactericidal efficiency and bactericidal characteristics of SEYT4. The safety of SEYT4 was evaluated in C57BL/6 female mice， and the efficacy of SEYT4 in removing pathogenic bacteria from the food chain was investigated by simulating pathogen contamination in leafy vegetables and kitchenware. The results showed that： SEYT4 contained a hairpin shaped double α-helical structure with a molecular mass of about 4.5 ku and a theoretical isoelectric point of 9.69. It could eliminate most of the highly toxic and drug-resistant Gram-positive and Gram-negative bacteria with a bactericidal rate as high as 99.99%. It had high activity at different temperatures， and the bactericidal effect was better in neutral and weak alkaline environment but inactivated in high salt environment. There was no hemolysis effect on mice erythrocytes. In the artificial pollution model of coriander， pathogenic bacteria in leaves and washing buffer could be removed about 90.00%， and more than 99.00% of pathogenic bacteria on food contact surface could be removed. The results showed that bacteriophage peptide SEYT4 was a novel antimicrobial peptide with good bactericidal effect and high safety， which could effectively prevent and control the pathogenic bacteria contaminated in food chain and was expected to be a practical disinfectant in food processing chain.

Abstract:In order to solve the current problem of manual measurement data entry in aquatic transactions that is susceptible to tampering and loss， this study proposes a secure model for collecting and transmitting such data， based on blockchain technology. Firstly， a data collection platform based on Raspberry Pi is designed for automatic data collection and input； Secondly， secure the transmission and storage of collected transaction data through smart contracts and consensus mechanisms； Finally， based on blockchain technology， a set of aquatic transaction measurement data collection and transmission system is designed to achieve aquatic transaction measurement data collection and query functions， and a test environment is built based on the Hyperledger Fabric platform for verification. The results show that the data collection and transmission system based on blockchain technology can effectively complete data collection， ensuring data security during data transmission and storage. The data transmission rate can reach 100%， and the packet loss rate is lower than traditional transmission systems. The results indicate that the model proposed in this study effectively improves the security and reliability of data， enhances the efficiency of aquatic product transactions， and is more suitable for practical applications in aquatic product transactions.

Abstract:A vane type pellet feeder was designed to solve the problems of inaccurate feeding quantity of the feeder system for current cage breeder ducks and the low degree of controlling individual feeding amounts during feeding process adverse to the breeding and selection of breeder ducks. A three factor and three level orthogonal experiment was established based on the experimental factors of feed passage pitch， blade spiral lift angle and blade speed， and the coefficient of variation of feed discharge per unit time of the feeder as evaluation indicators by analyzing the feeding and discharging principles of the feeder and the parameters of its core working components. The order of influence and optimal combination of various factors based on actual breeding needs were analyzed. According to the results of simulation， the primary and secondary order of the influence of each parameter on the uniformity of the discharge was the passing pitch of feed， spiral rising angle of discharge blade， and the speed of blade. When the pitch of feed passed through a spacing of 9.0 mm， the spiral rising angle of discharge blade was 71.5°， and the speed of blade was 58.4 r/min， the minimum discharge coefficient of variation of the feeder was 18.66%. The results of a bench test conducted to verify the discharge performance of the feeder under the optimal combination of parameters showed that the coefficient of variation of the feeder discharge was 18.74%， the discharge speed was 109.26 g/s， and the relative error between the preset amount of discharge and the actual amount of discharge was 3.07%， meeting the feeding needs of caged breeder ducks.

Abstract:A co-rotating and double-spiral fertilizer feeder with a double distributing wheel was designed to solve the problem of uneven fertilization， resulting in low utilization efficiency of fertilizer in traditional fertilizer feeder. The theoretical discharge capacity of fertilizer and the parameters affecting the uniformity of fertilizer were determined through theoretical analyses. A Box-Behnken experiment with three-factor and three-level was conducted using the pitch， center distance， and blade height of the fertilizer distributing wheel as experimental factors， and the fluctuation coefficient of fertilizer uniformity and average axial speed as experimental indexes. The results showed that the effect of pitch on the fluctuation coefficient of fertilizer uniformity was extremely significant （P<0.01）， while the effect of center distance and blade height on the fluctuation coefficient of fertilizer uniformity was significant （0.01<P<0.05）. The effect of pitch， center distance， and blade height on the average axial speed was extremely significant. When the center distance， the pitch and the blade height of the fertilizer distributing wheel was 48 mm， 32.5-33.2 mm and 13.5-14.7 mm， the fluctuation coefficient of fertilizer uniformity was ≤10%， and the axial speed of the fertilizer was ≥30 mm/s， the optimal performance of the fertilizer feeder was achieved. Under the optimized parameter combination， the relative error between the fluctuation coefficient of fertilizer uniformity in the bench experiment and simulation experiment was 1.47%， and the relative error between the volume of fertilizer distributed in a single lap in the bench experiment and simulation experiment was 1.96%， indicating that the bench experiment and simulation experiment are in good agreement. At different speeds， the fluctuation coefficient of fertilizer uniformity in the co-rotating and double-spiral fertilizer feeder was reduced by an average of 64.21% and the average fertilizer volume distributed in a single turn was increased by 72.16% compared to the single-spiral fertilizer feeder， indicating that the optimized the co-rotating and double-spiral fertilizer feeder has good fertilizer uniformity and a large flow rate of fertilizer. It will provide a useful guide for designing a co-rotating double-spiral fertilizer feeder.

Abstract:A digital unmanned farming system for pig was developed based on the integration of machine vision， big data， the internet of things （IoT）， intelligent modeling， and database technologies to solve the problems including the low efficiency of production， manual removal of manure， large size of equipment， high consumption of power， and the low accuracy of perception data faced by the majority of pig farms in China. A demonstration base for applying digital unmanned systems in pig farming was established. The digital unmanned technologies including intelligent visual monitoring of pig farming， remote operating system terminals， digitalized remote environmental monitoring IoT perception and intelligent scientific decision-making， automatic operation reminders， and the application of IoT intelligent devices were completed. A comparative experiment between the artificial farming and the digital unmanned farming was conducted by establishing application scenarios. The results showed that the established system realized non-contact pig face recognition through RKNet combined with HAM mechanism， with the accuracy of the pig face recognition model of 99.26%， the precision of 99.20%， and the model size of only 1.52 MB. It was deployed in embedded systems. The application of digital unmanned systems in pig farming reduced the average daily working hours of farmer from 4 h to 2.5 h， increased the average daily growth weight of pigs from 1.21 kg to 1.72 kg， and reduced the average daily abnormal behavior of pigs by 36.4%. It is indicated that establishing a digital unmanned system for pig farming can improve the efficiency of farming pig， reducing costs of labor， and increasing the economic benefits of the pig farming industry.

Abstract:Chlamydomonas reinhardtii was used as a model organism to deeply study the function mechanism of leucine rich repeat （LRR） in the process of innate immunity in the organism.The physicochemical properties of CrLRR-1 protein including secondary structure， hydrophilicity， and immunogenicity were predicted and analyzed with bioinformatics.The CrLRR-1 specific peptide was artificially designed and synthesized， then coupled with keyhole limpet hemocyanin （KLH） to immunize New Zealand white rabbits.The results showed that the antiserum titer was determined to be 1∶512 000 by indirect ELISA.The CrLRR-1 protein polyclonal antibodies were obtained after sequentially purifying the antiserum with Protein A and antigen affinity.The antibodies prepared with immunoblotting and immunofluorescence detection specifically recognized the endogenous LRR-1 protein in Chlamydomonas reinhardtii， and the CrLRR-1 protein was mainly localized on the cell membrane.It is indicated that the polyclonal antibody against CrLRR-1 protein were successfully prepared and identified.