Rice spikelet rot disease in China - 2. Pathogenicity tests, assessment of the importance of the disease, and preliminary evaluation of control options   总被引：2，自引：0，他引：2  

Shi-Wen HuangLing Wang  Lian-Meng LiuShao-Qing Tang  De-Feng ZhuSerge Savary 《Crop Protection》2011,30(1):10-17

In recent years, a rice panicle disease—rice spikelet rot, occurred seriously in large rice-growing area in China, causing the rice grains discolor, unfilled and deform. It does not only influence the rice yield, because of the colored pathogens and toxigenic, but also changes the appearance of the rice and reduces its quality. Spikelet rot disease influences on the rice production and market price, and causes harm to the safety and health of human and livestock. This paper makes effort to elucidate the occurrence, epidemic regularity of the disease, the pathogenicity of isolates. Fungicides to control the disease were preliminarily selected in lab and control efficiency test were conducted in field. The investigation results indicate that japonica varieties and their hybrid combination, tighten panicle varieties are easier to be infected by the disease than that of the indica rice varieties with loosen panicles. It was propitious to the disease occurrence and epidemic when rice late booting to flowering period met the overcast, rainy (high humidity) and warm (25-33 °C) climate. Indoor selection results showed that ketotriazole shows very good restraint effect on the pathogens. Seed treating with fungicide, spraying ketotriazole, carbendazim + thiram mixture or tricyclazole at later booting and/or flowering stage can reached over 70% control efficiency to the disease.  相似文献   

细胞传感器检测技术研究进展     

杨双  马军武 《安徽农业科学》2010,38(33):18673-18674,18677

细胞传感器以细胞作为敏感元件来研究信号识别、传导和指示的过程,可以用于细胞的信息功能及目的物质的检测,具有快速、敏感和特异的特点,已被广泛用于食品安全、农药残留、环境污染、病原微生物及生物安全检测等方面。笔者主要介绍了细胞传感器在病原体和毒素检测中的最新研究进展,分别叙述了现有的各类细胞传感器的元件构成和作用原理,并展望了细胞传感器未来研究和应用方面的发展方向。  相似文献   

三氯异氰尿酸对马铃薯连作障碍土壤微生物群落组成的影响     

周杨  石思雨  司友涛  马红亮  高人  尹云锋 《土壤》2022,54(4):756-762

采用盆栽试验,选择三氯异氰尿酸(TCCA)为土壤消毒剂,研究不同施用量TCCA对马铃薯连作障碍土壤微生物群落组成的影响。TCCA施用量设置分别为：0(CK),30 kg/hm²(S₃₀),60 kg/hm²(S₆₀)和120 kg/hm²(S₁₂₀)。结果表明：与CK处理相比,S₆₀和S₁₂₀处理显著提高土壤p H(P<0.05),分别提高0.15个和0.26个单位;显著增加土壤可溶性有机碳含量(P<0.05),增幅分别为30.4%和83.5%;显著提高土壤铵态氮含量(P<0.05),分别提高3.3倍和9.7倍。同时,S₆₀和S₁₂₀处理显著影响了土壤微生物优势菌属的相对丰度(P<0.05)。与CK处理相比,在门水平上,S₆₀和S₁₂₀处理下土壤变形菌门(Proteobacteria)的增幅达55.3%...  相似文献   

作物土传病害防控的健康微生物群落构建原理与实践     

蔡祖聪  黄新琦  赵军 《土壤学报》2023,60(5):1213-1220

植物-土壤反馈效应及农田生产特点决定了农田土壤生产力的不可持续性,因而必须采用适当的措施方可保持地力常新。施用化肥解决了农田土壤的养分贫化问题,极大地提高了作物产量,但激发了土传病原生物的活性,作物土传病频发成为制约集约化农业可持续发展的瓶颈问题。现有的研究成果表明,地上生物多样性与土壤微生物多样性紧密联系,植物提供的有机物质是连接二者的物质基础。单一作物种植的集约化农业提供给土壤微生物可利用的有机物质来源单一,导致土壤微生物多样性下降,削弱对土传病原生物致病性的抑制作用。本文提出,在作物生长过程中添加土壤有益微生物偏好利用的有机物质,激活土壤有益微生物,可能是维持集约化农业土壤生物健康,抑制作物土传病的有效途径。为此,有必要开展各种土壤微生物偏好利用的有机物质以及作物生长过程中如何施用有机物质的方法。  相似文献   

Grower perceptions of biotic and abiotic risks of potato production in South Africa     

《Crop Protection》2016

Growers' surveys took place in all sixteen potato growing regions of South Africa in 2013 and 2014. The agro-ecological climate of these regions is diverse and potato is produced in rainy or dry seasons, in winter or summer seasons, or year round. Growers were asked how often in ten years crops suffered more than 25% yield losses due to extreme weather events related to precipitation events such as hail, floods and droughts, and to temperature-related events such as frost and heat waves. Simultaneously they were asked their opinion about occurrence and severity of diseases caused by potato viruses, fungi and bacteria and pests such as nematodes, tuber moths, aphids and leaf miners. Weather related hazards resulted in losses over 25% virtually each year in the Gauteng growing region due to hail, frosts and floods; losses occurred less than once every five years, for example due to extremely high temperatures, in the Sandveld area where growers take a risk by producing potatoes in hot summers. Regarding the biotic factors, every pest or pathogen assessed was reported to occur on at least one farm in each growing region. Countrywide the lowest frequency of 50% was recorded for powdery scab whereas the insects tuber moths, leaf miners and aphids were reported most frequently, by between 88% and 98% of the growers. The complex of silver scurf and black dot resulted in the greatest yield losses in all growing regions, followed closely by tuber moth, early blight and the blackleg/soft rot disease complex. Yield losses due to potato virus Y, potato leaf roll virus and aphids were not reported as being very severe. When the growers' perceptions of severity of biotic factors were accumulated, significant differences between the regions appeared, with the Eastern Cape most prone with an accumulated score of 700 due to an array of pests and diseases, and the North–West with a score of only 50 mainly attributed to root knot nematodes. Growers were also asked how frequently biocides were applied to potato to control soil-borne organisms (nematicide and seed treatment), foliar fungi or insects. There were no significant correlations between frequency of biocide applications and severity of the disease as reflected in yield losses, most likely because growers use biocide applications as insurance against pests and diseases. This is common among crop farmers around the world. Although potato production in South Africa appears to carry more risks than production elsewhere, South African commercial potato growers are economically competitive when compared to growers in other areas of the globe, with comparable planting conditions and risks.  相似文献   

花壳辣椒病菌侵染对色素及活性氧水平的影响     

郑文宇  丁筑红  刘海  邓程  肖治柔 《西南农业学报》2013,26(3)

为探讨花壳辣椒病菌对采后辣椒色素及组织活性氧水平的影响,采用新鲜红辣椒(Capsicum annuum L.)接种“花壳”病菌株,跟踪辣椒色素变化并动态分析辣椒组织活性氧超氧阴离子(O2-)的产生速率、过氧化氢(H2 O2)、羟自由基(·OH)含量的变化.结果表明:花壳辣椒病菌组辣椒色泽发生明显褪变,辣椒O2-的产生速率和羟自由基的含量变化总体呈先下降后显著上升的趋势,出现单个低峰值；H2O2的含量变化总体呈先下降后上升,到达峰值后又有下降的趋势,其中,F101(lrpex lacteus)和F121(Cladosporium cladosporioides)病菌对辣椒组织活性氧的影响较其他病菌显著(P＜0.05).而对照组辣椒色素未发生褪变,活性氧水平总体变化微小,非花壳辣椒病菌组辣椒色素褪变以及组织活性氧水平变化程度低于花壳辣椒病菌组.该病菌侵染导致辣椒色素褪变,同时辣椒组织活性氧水平发生明显变化,不同花壳辣椒病菌对活性氧水平的影响存在差异.  相似文献   

Tree Diseases,Canopy Structure,and Bird Distributions in Ponderosa Pine Forests     

《Journal of Sustainable Forestry》2013,32(2):17-45

Abstract

We examined how canopy patterns at the landscape scale can influence bird community composition, abundance, or distribution. Our long-term goal is to determine how diseases and other small-scale disturbances that change canopy patterns influence bird distribution. Little is known about these relationships, partly because most measures of disturbance are based on timber production metrics. We developed a spatially dependent metric referred to as canopy closure roughness, which was significantly correlated to bird diversity on 4 ha sample plots, and used it to generate a spatial model showing the distribution of bird diversity at a resolution of 30 mover an area of 1 million acres (the entire Black Hills National Forest). Number of bird species per stand varied between 2 and 16. Number of species and bird diversity were positively related to intensity of tree cutting. Most common bird species were yellow-rumped warbler, dark-eyed junco, Townsend's solitaire, black-capped chickadee and red-breasted nuthatch. The spatial model of bird diversity showed clusters of high diversity at different locations within the forest. These methods may help lead to better tools for managing the linkages between specific disturbances and bird usage and enable more effective disturbance management by offering a platform for spatial planning.  相似文献   

Conservation education needs more parasites     

Elizabeth Nichols  Andrés Gómez 《Biological conservation》2011,(2):937-941

Formal training in conservation biology education is an important component of the suite of solutions to current environmental problems. As conservation biology textbooks underpin many conservation education programs at both undergraduate and graduate levels, the portrayal of conservation issues and coverage of specific biotic groups plays a potentially important role in guiding the training of the next generation of conservation professionals. Parasites represent the majority of species diversity on earth, play critical roles in ecology and evolution, and are often at higher risk of decline and extinction than their free-living counterparts. Yet parasites continue to receive scant attention from conservation scientists and educators. We searched the index of 77 English language conservation biology textbooks for parasite or pathogen related content, published between 1970 and 2009. When present, we categorized a textbook’s parasite content as positive, neutral or negative with respect to the author’s portrayal of parasite biodiversity. The vast majority (72%) of conservation textbooks either portray parasites uniquely as threats to conservation goals established for free-living species or do not mention parasites at all. While no single textbook can be expected to provide extensive treatment of conservation-related topics across all biological groups, we outline three reasons why parasites should feature more prominently in formal conservation education, and suggest several ways in which greater incorporation of these parasite topics could strengthen the teaching and practice of conservation biology.  相似文献   

苹果花叶病研究进展     

李春霞 《陕西农业科学》2021,(8):82-86

苹果花叶病是一种世界性的病害,在各苹果产区危害日趋严重,给苹果高产优质带来巨大影响。为了对苹果花叶病更加系统全面的认识,寻找更有效的防治方法与措施。笔者从苹果花叶病对生长结果、叶绿素含量、光合作用和细胞性态结构等方面的影响、花叶病的症状表现、果树病毒的检测方法、苹果花叶病病原种类及检测、花叶病的防治方法等方面进行综述。同时提出今后研究的方向。  相似文献   

玉米穗腐病研究进展   总被引：12，自引：0，他引：12  

任金平 《吉林农业科学》1993,(3):39-43,60

玉米穗腐病是世界性严重病害。据报道世界上引起玉米穗腐病的病原菌达数十种,串珠镰刀苗(Fusarium mouiliforme)是大部分国家和地区的优势病原菌。该病的发生与品种、气候条件、果穗着生状态,鸟及昆虫的取食等有关。在抗性鉴定中,牙签接种、注射接种和喷雾接种是目前最常用的按种方法,寄主与病原物之间存在着显著的相互关系,抗性属核遗传,附加基因效应明显,为不完全显性。培育和推广抗病品种是目前唯一有效可行的防治方法。  相似文献