烟叶不同生育期病虫害防治要点分析

充分了解和掌握病虫害发生规律及传染途径,做到防重于治,科学、合理、安全使用农药,才能在病虫害防治方面取得明显效果。     

淡水养殖鱼类主要细菌性传染病快速诊断的研究——鱼病诊断箱的应用试验

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     

化学诱抗剂在控制甜瓜采后病害中的应用及其作用机制的研究进展

介绍了化学诱抗剂在甜瓜果实采后病害控制中的应用,分别从活性氧代谢、苯丙烷代谢、细胞结构及病程相关蛋白四个方面综述化学诱抗剂对甜瓜果实采后贮藏病害的作用机制,并重点从分子生物学层面对化学诱抗剂控制甜瓜果实采后贮藏病害作用机制的研究进行了展望,以期为防控甜瓜采后病害,延长其贮藏期提供理论基础和技术参考。     

有关鸡瘟病毒防治方法的讨论

鸡瘟是病毒引起的一种急性传染病。鸡瘟的季节一般在春季和秋季发生,它的传染比较迅速,如果没有进行及时的防控,流行起来,具有很高的死亡率。     

露地盆栽月季主要病虫害及绿色防控技术

露地盆栽月季在栽培过程中极易受黑斑病、白粉病、霜霉病、灰霉病、月季长管蚜、二斑叶螨、西花蓟马、花蓟马、月季叶蜂等病虫害侵染,使月季花期缩短,花朵变小,植株矮小,严重影响其观赏价值。本文着重论述露地盆栽月季主要病虫害及绿色防控技术。     

Applications of ionizing radiation for the control of postharvest diseases in fresh produce: recent advances

Postharvest diseases cause considerable losses to harvested fruits and vegetables worldwide. In addition to various treatments to control postharvest losses caused by pathogens, the global trend is shifting toward more ecofriendly alternatives safer to human health. Thus far, the main approach to postharvest disease control has mostly relied on the use of chemicals. However, the intense use of chemical fungicides has caused side effects such as environmental issues and evolution of fungicide‐resistant isolates. With increasing demand for the use of non‐chemicals, ionizing radiation has been investigated for application in many aspects of postharvest treatment, especially as an approach with significant potential for the control of postharvest disease. Recently, a number of more or less technologically advanced methodologies, e.g. irradiation combined with other types of treatments and induced disease‐resistance, have been developed to control postharvest diseases as well as to increase the quality and storage life of fresh commodities. Challenges for future application of irradiation in fresh produce are the cost, lack of irradiation facilities, lack of knowledge about optimal conditions for different commodities, and lack of acceptance of irradiated fresh produce. This review aims to document the advances in understanding of the effects of irradiation on postharvest disease, the possible modes of action, and the perspectives in commercial use.     

Lactococcus lactis,causative agent of an endocarditis valvularis and parietalis thromboticans in the allis shad,Alosa alosa (L.)

Since the 1940s, the anadromous allis shad, Alosa alosa (L.), has suffered population declines throughout its distribution range in Europe. In context of EU‐LIFE projects for the reintroduction of the allis shad in the Rhine system, a comprehensive study was started in 2012 to investigate infectious diseases occurring in allis shad. In course of the study, 217 mature and young‐of‐the‐year allis shad originating from the wild population from the Gironde–Garonne–Dordogne system (GGD‐system) and the Rhine system as well as 38 allis shad from the breeding population were examined by use of bacteriological and histological methods. In 2012 and 2014, an endocarditis valvularis thromboticans caused by a coccoid bacterium was detected in 16% and 25% of mature allis shad originating from the GGD‐system. Results of microbiologic examinations, including biochemical characteristics, matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS) and 16S rRNA gene sequence analysis, revealed Lactococcus lactis as causative agent of this infection. This is the first report of an endocarditis valvularis and parietalis thromboticans caused by Lactococcus lactis in fish. Possible sources of infection as well as the impact for the reintroduction programme are discussed.     

基于混合蛙跳算法的马铃薯病害图像分割优化

针对Otsu算法对直方图呈现多峰多谷的复杂马铃薯病害图像分割效果不佳的问题,结合混合蛙跳算法(shuffled frog leaping algorithm,SFLA)提出了一种Otsu-SFLA分割优化模型,将Otsu病害图像的分割结果作为SFLA算法的优化起点,进行复杂背景的马铃薯病害图像的分割优化,将马铃薯叶枯病、马铃薯晚疫病、马铃薯菌核病、马铃薯根腐线虫病、马铃薯灰霉病的病害图像作为分割对象进行分割,分割匹配率分别为97.0%、96.2%、96.9%、95.7%、94.8%,平均分割匹配率为96.1%,错误率分别为1.6%、1.1%、1.2%、1.1%、1.4%、平均错误率为1.3%,正确率分别为95.4%、95.1%、95.7%、94.6%、93.4%,平均正确率为94.8%,表明Otsu-SFLA模型可有效从复杂马铃薯病害图像中获取病斑区域。     

珍贵树种蚬木研究进展

通过对珍贵树种蚬木（Excentrodendron hsienmu）的相关研究进行综述,从生物特性、群落结构、生理活动、种子、苗木培育、栽培技术、病虫害防治等方面综合总结分析,提出该树种今后重点研究的方向。     

基于改进VGG卷积神经网络的棉花病害识别模型

为实现自然条件下棉花病害图像准确分类,提出基于改进VGG-16卷积神经网络的病害识别模型。该模型在VGG-16网络模型基础上,优化全连接层层数,并用6标签SoftMax分类器替换原有VGG-16网络中的SoftMax分类器,优化了模型结构和参数,通过微型迁移学习共享预训练模型中卷积层与池化层的权值参数。从构建的棉花病害图像库中随机抽取病害图像样本作为训练集和测试集,用以测试该方法的性能。试验结果表明:该模型能有效提取出棉花病害叶片图像的多层特征图像,并通过Relu激活函数的处理更能凸显棉花病害的边缘信息与纹理信息,分辨率为512像素×512像素图像在样本训练与验证试验效果最好。在平均识别准确率方面,本研究模型较BP神经网络、支持向量机、AlexNET、GoogleNET、VGG-16NET效果最好,达到89.51%,实现对棉花的褐斑病、炭疽病、黄萎病、枯萎病、轮纹病、正常叶片的准确区分。该模型在棉花病害识别领域具备良好的分类性能,可实现自然条件下棉花病害的准确识别。