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以《中国期刊全文数据库》作为数据来源,采用文献计量学方法对1990~2010年烟粉虱研究文献的年份、核心期刊、文献主要产出单位、核心作者群分布情况进行统计分析,在总文献量534篇、第一作者343人中,确定了9位核心作者和8种核心期刊。 相似文献
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[目的]评估6种药剂对蓟马的防治效果。[方法]选用6种不同类型的药剂对芦笋蓟马进行大田药效试验,调查药前、药后虫口密度,计算虫口减退率和防治效果。[结果]0.3%苦生碱AS 60 mg/kg、6.0%乙基多杀菌素SC 600 mg/kg和2.5%多杀菌素SC 350mg/kg对蓟马的防效较好,达到90%左右,明显优于其他处理;10.0%双三氟虫脲EC 2 000 mg/kg的防效次之,达到80%左右,明显优于10.0%烯定虫胺AS 500 mg/kg和24.0%氰氟虫腙SC 2 400 mg/kg。[结论]0.3%苦生碱AS、6.0%乙基多杀菌素SC和2.5%多杀菌素SC分别以剂量60、600和350 mg/kg防治芦笋田蓟马,速效性好,持效期长,对芦笋安全,可在芦笋生产上推广使用。 相似文献
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为明确烟粉虱Bemisia tabaci MED隐种优势寄生蜂海氏桨角蚜小蜂Eretmocerus hayati ZolnerowichRose与浅黄恩蚜小蜂Encarsia sophia GiraultDodd对其控制效果的影响,在棉田尼龙纱网笼罩中释放烟粉虱之后,再分别单独释放海氏桨角蚜小蜂、浅黄恩蚜小蜂以及二者以不同比例组合(1∶1、1∶3、3∶1)释放,定期调查统计2种蚜小蜂对烟粉虱的寄生量和烟粉虱的种群动态。结果表明,相对于不放蜂对照,自首次放蜂后40 d开始,所有放蜂处理均能显著降低烟粉虱若虫种群密度,每100 cm~2叶片上均少于1.00头,但各处理间的烟粉虱种群密度无显著差异;海氏桨角蚜小蜂和浅黄恩蚜小蜂以3∶1比例组合释放的处理中对烟粉虱的寄生量最高,每100 cm~2棉花叶片上能达到4.25头。表明在棉田中对烟粉虱进行生物防治时,以初级寄生蜂海氏桨角蚜小蜂与复寄生蜂浅黄恩蚜小蜂为3∶1的比例释放,可以到达较好的控制效果。 相似文献
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Socio-Economic and Scientific Impact Created by Whitefly-Transmitted,Plant-Virus Disease Resistant Tomato Varieties in Southern India 下载免费PDF全文
John Colvin N Nagaraju Carlos Moreno-Leguizamon R M Govindappa T B Manjunatha Reddy SA Padmaja Neena Joshi Peter M Hanson Susan E Seal V Muniyappa 《农业科学学报》2012,11(2):337-345
Research carried out to assess the impact of open-pollinated Tomato leaf curl virus (ToLCV)-resistant tomatoes and hybrids on the livelihoods of resource-poor farmers in Southern India is described and discussed. Three high-yielding ToLCV-resistant tomato varieties were developed initially using conventional breeding and screening techniques involving inoculation by ToLCV-viruliferous whitefly, Bemisia tabaci. In 2003 and 2004, respectively, these varieties were released officially by the Karnataka State Seed Committee and the Indian Ministry of Agriculture through notification in the Gazette of India. From 2003 to 2005, eleven seed companies bought breeder seed of the ToLCV-resistant varieties and used them to begin breeding F1 hybrids from them. Socio-economic studies carried out to assess the benefits obtained from growing the ToLCV-resistant varieties found that farmers could gain up to 10 times the profit by growing the ToLCV-resistant varieties compared to the pre-existing ToLCV-susceptible varieties. Adoption of ToLCV-resistant tomatoes was also associated with reduced pesticide use. Extra income from tomato sales was prioritised by farmers to pay for children's education, better nutrition and medicines. In a joint effort with the commercial seed sector in India, a promotional field day was organised in 2007. As well as the three ToLCV-resistant varieties, 62 ToLCV-resistant hybrid tomatoes were exhibited during a farmer-field day by 17 commercial seed companies and several public institutes. Tomatoes with ToLCV-resistance are now grown widely in South India and seeds of the three open-pollinated varieties have been distributed to more than 12 countries. In 2007, a conservative estimate of the financial-benefit to cost of the research ratio was already more than 837:1. 相似文献
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Kontsedalov S Zchori-Fein E Chiel E Gottlieb Y Inbar M Ghanim M 《Pest management science》2008,64(8):789-792
BACKGROUND: The presence of certain symbiotic microorganisms may be associated with insecticide resistance in insects. The authors compared the susceptibility of two isofemale lines, Rickettsia-plus and Rickettsia-free, of the sweet potato whitefly Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae) to major insecticides from different chemical groups, including imidacloprid, acetamiprid, thiamethoxam, pyriproxyfen, spiromesifen and diafenthiuron. RESULTS: While the Rickettsia-plus and Rickettsia-free lines showed no differences in their susceptibility to imidacloprid and diafenthiuron, higher susceptibility of the Rickettsia-plus line to acetamiprid, thiamethoxam, spiromesifen and especially pyriproxyfen was observed. LC(90) values indicated that the Rickettsia-free line was 15-fold more resistant to pyriproxyfen than the Rickettsia-plus line. CONCLUSION: Findings indicate that the infection status of B. tabaci populations by Rickettsia is an important consideration that should be taken into account when performing resistance monitoring studies, and may help in understanding the dynamics of B. tabaci resistance, symbiont-pest associations in agricultural systems and the biological impact of Rickettsia on whitefly biology. 相似文献
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寄主植物对B型烟粉虱个体发育和种群繁殖的影响 总被引:2,自引:0,他引:2
同一原始种群B型烟粉虱[Bemisia tabaci(Gennadius)],分别在甘蓝、一品红、棉花、番茄和黄瓜连续隔离饲养大约20代后形成5种对应的烟粉虱种群,研究其在甘蓝上各虫态大小、存活率、发育历期、成虫寿命和平均产卵量等生物学参数。在(25±1)℃条件下,一品红种群烟粉虱的1、2、3龄若虫体长和宽均显著低于其他4个种群烟粉虱;发育时间以甘蓝和一品红种群烟粉虱(20.44、19.69d)显著高于番茄种群烟粉虱(19.13d);雌虫寿命以甘蓝种群烟粉虱显著低于一品红、棉花、番茄和黄瓜种群烟粉虱;平均单雌产卵量以一品红种群烟粉虱(169.30粒)显著高于其他4个种群烟粉虱;5个种群烟粉虱在甘蓝上的总存活率均无显著差异。 相似文献
90.