Variability in response to toosendanin in a laboratory colony of<Emphasis Type="Italic">Trichoplusia ni</Emphasis>     

Jennifer H. Cameron  Murray B. Isman  Mahesh K. Upadhyaya 《Phytoparasitica》2007,35(2):119-122

Laboratory rearing of insects for scientific research ensures a constant supply of insects. However, laboratory colonies may diverge genetically and/or phenotypically from wild populations due to selection pressures in their artificial environment. This study examined how variation in a colony ofTrichoplusia ni influenced reproducibility over time of bioassays of toosendanin (a limonoid extracted from the bark ofMelia azedarach). In four of five experiments insect growth was reduced significantly (P=0.05) by the presence of toosendanin in the diet. The fifth experiment showed the same trend, but the effect was not significant. Mean larval mass of both control and treated insects also varied greatly among experiments. The considerable variability observed in this population highlights the importance of replicating experiments in time, and not just space, to confirm reproducibility of treatment effects. http://www.phytoparasitica.org posting Jan. 23, 2007.  相似文献   

A survey of the genera of<Emphasis Type="Italic">Microgaster</Emphasis> latreille and<Emphasis Type="Italic">Hygroplitis</Emphasis> thomson (Hymenoptera: Braconidae: Microgastrinae) from China     

Wei-An Xu  Hong-Yan Han 《Phytoparasitica》2007,35(1):86-99

The genera ofMicrogaster Latreille 1804 andHygroplitis Thomson 1895 from China are presented systematically in this paper. Thirty-two species ofMicrogaster and three species ofHygroplitis are known in China. Diagnosis, character variation, distribution and host of each species among the two genera are presented, including its host and distribution. Keys to the species ofMicrogaster andHygroplitis are given. http://www.phytoparasitica.org posting Dec. 19, 2006.  相似文献   

江苏省扬中杂草稻生物学特性初步研究   总被引：9，自引：1，他引：9  

杨杰  仲维功  陈志德  王军  汤陵华  闵思桂 《杂草科学》2007,(3):13-15

扬中杂草稻具备杂草稻的基本特性，又是一个具有遗传多样性的混合群体。扬中杂草稻具有较强的休眠性，但比稽稻等代表性的杂草稻弱。扬中杂草稻落粒性强，与稽稻等代表性杂草稻表现基本一致。亲和性研究表明，扬中杂草稻与广亲和品种02428（S5^n）正反交杂种F1结实率正常，而与籼稻特青和扬稻6号的杂种F1生育期超亲，在南京不能正常抽穗。与粳稻武运粳7号、粳稻品系27114的杂种F1表现为半不育。  相似文献   

用异丙隆防除麦田碱茅的研究     

杨照东 《杂草科学》2007,(3):43-45

50％异丙隆防除麦田碱茅的最佳施药时期为小麦2叶1心期，株防效达97．7％，鲜重防效达98．75％。随用药剂量的增加，防效提高，以1800g／hm^2效果最好，株防效达97．93％，鲜重防效达99．3％。不同时期宜选用不同剂量，播后苗前施药，宜选用1800g／hm^2，2叶1心期施药宜选用900g／hm^2，3叶1心期施药宜选用1500g／hm^2。  相似文献   

采用孢子萌发法测定化合物对黄瓜白粉病菌的生物活性   总被引：1，自引：0，他引：1       下载免费PDF全文

杨小军  ;倪汉文;杨立军;王少南;喻大昭 《植物保护》2007,33(1):75-77

接种黄瓜白粉菌后16 h的黄瓜叶片用透明胶带在子叶表面粘孢子取样的平均发芽率与用台盼蓝染色后在光学显微镜下调查的发芽率分别为83.7%和85.0%,t测验无显著差异,表明透明胶带取样的发芽率可以代表黄瓜叶片上白粉病菌孢子的发芽率。采用孢子萌发法和叶碟法分别测定了醚菌酯、植物源活性组分大黄素甲醚(P3D)对8个黄瓜白粉菌菌株的EC₅₀。统计结果表明:采用两种方法测定醚菌酯P、3D对黄瓜白粉菌的EC₅₀的相关系数的平方值分别为0.880、.99,表明两种方法的测定结果有很强的相关性;采用该孢子萌发法可评价化合物对植物专性寄生病菌如白粉菌孢子萌发的生物活性。  相似文献   

烟草环斑病毒DB-RT-Realtime PCR检测方法研究   总被引：1，自引：0，他引：1       下载免费PDF全文

郑耘  杨伟东  陈枝楠  李明福  章桂明  余道坚  张永江 《植物保护》2007,33(1):117-120

  相似文献   

秆野螟属(Ostrinia)系统进化与分类研究进展   总被引：5，自引：0，他引：5       下载免费PDF全文

杨瑞生  ;王振营;何康来 《植物保护》2007,33(2):20-26

秆野螟属(Ostrinia)昆虫全球分布20种,寄主广泛,在农业生产中具有重要的经济意义。由于该属地理分布广泛,形态特征复杂,寄主和生态区重叠严重,秆野螟属系统发育研究还存在很多问题尚未解决。本文综合中国秆野螟属分类概况,对目前应用于秆野螟属系统发育研究的各种性状,包括形态特征、性信息素(生殖隔离)以及分子水平的研究进展作了阐述,并针对秆野螟属研究内容的复杂性及其研究现状,提出了相关对策。  相似文献   

微卫星DNA标记及其在检疫性实蝇种群遗传学中的研究应用          下载免费PDF全文

伍祎  李志红  康芬芬  杨定  吴佳教 《植物保护》2007,33(4):1-6

微卫星DNA是一种广泛用于种群遗传学研究的分子标记技术,具有共显性标记、反应速度快、重复性好和结果可靠等特点。本文在概述微卫星标记的原理、特点、位点筛选和引物设计的基础上,系统分析了该技术在检疫性实蝇(小条实蝇属、果实蝇属等)种群遗传关系中的研究与应用。  相似文献   

Mottle necrosis of sweet potato caused by <Emphasis Type="Italic">Pythium scleroteichum</Emphasis> in Japan and varietal difference in susceptibility to the disease     

Motoaki Tojo  Ken Watanabe  Kenichi Kida  Yingjie Li  Shuhei Numata 《Journal of General Plant Pathology》2007,73(2):121-124

Severe mottle necrosis (Shirogusare-byo in Japanese) was found on mature tubers of sweet potato (Ipomoea batatas) in Ibaraki Prefecture in October 2004. The causal organism was identified as Pythium scleroteichum hitherto unknown in Japan. Sweet potato cultivar Purple Sweet Lord was more susceptible than cultivars Beniazuma, Benimasari, Koukei-14, and Tamayutaka to the pathogen at 25°C, while this difference in the susceptibility was not clear at 15°C.  相似文献   

<Emphasis Type="Italic">Spongospora subterranea</Emphasis> soil contamination and its relationship to severity of powdery scab on potatoes     

Takato Nakayama  Mitsuo Horita  Tadayuki Shimanuki 《Journal of General Plant Pathology》2007,73(4):229-234

We investigated soil contamination by Spongospora subterranea f. sp. subterranea (Sss) and disease severity of powdery scab in 29 potato fields in Hokkaido, Japan, using a hydroponic culture method with tomato seedlings as bait plants. The quantity of Sss infection on the roots of bait plants was evaluated using the polymerase chain reaction (PCR) and expressed in terms of the infection potential in the soil. The infection potential was positively correlated with the disease severity of harvested tubers, whereas the spore ball density determined using PCR had an indistinct relationship with disease severity. The infection potential can be useful in evaluating soil contamination and in applying countermeasures against powdery scab.  相似文献