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81.
针对现有茶叶病害识别方法病害信息挖掘不足导致识别准确率低的问题,该研究提出了一种基于二维离散小波变换(discrete wavelet transform, DWT)和MobileNetV3融合的茶叶病害识别模型CBAM-TealeafNet。为增强网络对病害频域特征的检测能力,将2D DWT获取的频域特征与bneck结构提取的深度特征融合,形成频域与深度特征融合的识别网络。为提高特征提取能力,在bneck结构中,嵌入卷积块注意模块 (convolutional block attention module, CBAM),为特征通道分配相应权重。为解决样本类别不平衡对识别模型性能的影响,利用焦点损失函数取代交叉熵损失函数以提高识别精度。经验证,CBAM-TealeafNet在5种不同茶叶病害上整体识别准确率达到98.70%,参数量为3.16×106,相对MobileNetV3,准确率提升2.15个百分点,参数量降低25.12%。该方法可为茶树叶部等作物病害轻量级识别研究提供模型参考。  相似文献   
82.
为探索化肥农药减施融合使用技术,设计肥料和农药两因素三水平试验,研究不同化肥农药减施组合对水稻主要病虫害发生及产量的影响。结果发现:减肥有减轻病虫发生程度的趋势,减药有加重病虫发生程度的趋势;减肥可显著影响水稻纹枯病、第4代稻飞虱、稻纵卷叶螟发生程度,减药可显著影响水稻纹枯病、第3和4代稻飞虱、稻纵卷叶螟发生程度,但两者均对稻瘟病、稻曲病、二化螟发生程度无显著影响。减肥30%时实测减产10.29%,对产量影响显著;减肥低于20%时,绿色助剂替代处理和生物农药替代处理实测产量比对照处理增产0.38%和2.49%,生物农药替代和绿色助剂替代均可作为化学农药减量的技术措施。  相似文献   
83.
应用以葡萄球菌A蛋白协同凝集试验(SPA-COA)为主要检测手段的鱼病诊断箱,于1995 ̄1997年在吉林,辽宁等7省进行现场检测试验。结果,61个渔场11个品种的516尾病鱼有菌生长的285尾,经SPA-COA鉴定阳性数为239尾,占有菌生长的83.86%,12个渔场5个品种1216尾假定健康鱼有菌生长的为28尾,经SPA-COA鉴定阳性数为22尾,占有菌生长的78.57%,认为本诊断箱适用于基  相似文献   
84.
运用茎尖培养、热处理结合茎尖培养、病毒唑结合茎尖培养、热处理加病毒唑结合茎尖培养4种方法,脱除西伯利亚百合品种CMV、LSV和LMoV病毒,分析了4种处理后的成苗率和脱毒率。结果表明:以热处理加病毒唑结合茎尖培养法效果最为明显。  相似文献   
85.
 ‘北红’葡萄新品种由‘玫瑰香’与‘山葡萄’杂交育成。浆果在北京地区9月底成熟。果粒圆形,蓝黑色,果粒质量1.57g,果穗质量160.0 g,浆果可溶性固形物含量23.8 %~ 27.0 %,含酸量0.89~1.26 %。早果性及丰产性强。抗寒、抗病能力特强。酿成的酒深宝石红色,酒体平衡,酒质上等。  相似文献   
86.
环境污染已成为当前蚕桑安全生产的最大危害,桑树病虫为害也呈趋重的态势。探讨了盐城市病虫危害、环境污染状况及其防制的主要做法和设想。  相似文献   
87.
Liquid chip technology is a novel biomolecular detection technology which integrates laser technology,flow cytometry,digital signal processing and traditional chemical technology.It is widely used in various immunological analysis and nucleic acid detection.Single and mutiplex analysis are supported,with protein and nucleic acid targets detected in a variety of detection methods in high throughput manner.It has advantages of high throughput,easy operation,wide range of application,good repeatability,high specificity,less sample needed,high sensitivity and stablility,and low cost.Therefore,they are gradually replacing the traditional detection and quantitative pathogen methods,such as Real-time fluorescent quantitative nucleic acid amplification detection system (qPCR),enzyme-linked immunosorbent assay (ELISA) and other detection methods.Animal infectious diseases seriously endanger the development of the breeding industry,futhermore,some zoonoses such as highly pathogenic avian influenza also pose a serious threat to human health.An efficient and sensitive diagnostic system will help to screen a large number of samples during the outbreak of infectious diseases and prevent the spread of infection.The development of liquid chip technology provides a new platform for high-throughput detection and disease prevention.In this review,the principle and advantages of liquid chip technology are briefly described.The research progress of liquid chip technology in the detection of animal infectious diseases,including pigs diseases,poultry diseases,rabbit diseases,dog diseases,rodent diseases and other animal infectious diseases are summarized.We believe that in the future,this technology will become an important analytical and testing tool in clinical diagnosis,basic research,new drug development,judicial identification,food health supervision,biological weapons prevention and other fields.The development of this technology will greatly promote the research and development of life science.  相似文献   
88.
Over the past 20 years,with the continuous promotion of the genetic improvement plan of dairy cow population and the continuous improvement of feeding technology,the intensive level and milk yield of dairy cow population in China are continuously improving.However,the reproduction data over the years showed that the more milk yield,the more obviously decline in reproductive performance,and the more prominent of the reproductive problems.The decline of fertility caused by high yield has become the bottleneck of the development of dairy industry in China and even in the world.In dairy farming,there are many factors that cause the reduction of reproductive performance of high-yield dairy cows,including genetic factors,environmental factors and disease factors.Recently,the influence of disease factors on reproductive performance of dairy cows has become more and more prominent.According to the location of the disease,the diseases can be divided into genital diseases and non-genital diseases.This paper discussed the relevant research data on the effects of different diseases on the reproductive performance of dairy cows in recent years,and focusing on the analysis of the molecular mechanism of diseases affecting the reproductive performance of dairy cows through the nervous system,reproductive endocrine system and humoral immune system.The prospect and thinking for the future research of diseases and reproductive performance of high-yield dairy cows were put forward to provide reference and theoretical basis for improving the reproductive efficiency and economic benefits of high-yield dairy cows in China.  相似文献   
89.
Objective To determine in Australian pig herds the accuracy of French protocols for risk factor assessment.
Procedure Data on health indicators and risk factors were collected for three syndromes, 'pre-weaning diarrhoea', 'post-weaning diarrhoea' and 'respiratory problems', using the French protocols. The protocols were used on 118 occasions in 32 Western Australian pig herds during 3 years (1988 to 1991).
Results There was a wide variation in pre-weaning performance, for example growth rate was 107 to 273 g/day (< 200 g/day in 33% of herds). Respiratory lesions at weaning were associated with poor pre-weaning performance. Post-weaning (21 days after weaning) growth rate was 114 to 408 g/day (< 250 g/day in 54% of herds). In the grower herds, 91% of herds had pneumonia, and growth rate was 439 to 625 g/day (< 550 g/day in 54% of herds). Pleurisy as well as pneumonia was associated with reduced growth rate. The risk factor most closely associated with respiratory health status was air volume per pig.
Conclusion Risk factors were most accurate at predicting the health status in post-weaning problems. A weaning weight of at least 7.9 kg and weaning age of 30 days optimised weaner performance. Stocking densities and shed designs providing at least 3 m3 air volume and 0.6 m2 floor space per pig throughout the growing phase should be considered for an improved respiratory health status. Australian pig sheds often do not provide a satisfactory environment for optimum health. The technique of risk factor assessment as an aid to the maintenance of health in pig herds is applicable in Australia, but further research is necessary to determine the most important Australian risk factors.  相似文献   
90.
摘要:针对大棚辣椒多年连续种植,导致大棚辣椒病虫害发生逐年加重、辣椒大幅减产、品质下降等问题,基于大棚辣椒主要病虫害发生特点及规律,通过试验和示范、推广,形成了1套以生态调控技术、生物防治技术、害虫诱杀技术和科学用药技术等为主要内容的全程绿色防控模式,并在生产中不断推广应用,病虫害防治效果达95%以上,化学农药使用量减少50%以上,农药残留合格率100%,提高了辣椒产量和品质,保证了农产品质量安全,生态效益显著;绿色防控区产投比(6.781)明显高于常规防控区(4.681),667 m2净收益较常规防控区高出4 111.0元,经济效益较好。  相似文献   
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