薇苷菊乙醇提取物对桔全爪螨种群的控制作用

研究薇苷菊(Mikaniamicrantha)乙醇提取物对桔全爪螨(Panonychuscitri)种群的控制作用,并比较其与常用杀螨剂哒螨灵的效果.在实验室用0 . 1、0 . 2、0 . 4g·L-13个浓度提取物分别喷布桔全爪螨卵、幼螨和若螨,除了0 1g·L-1浓度处理对卵没有效果外,该处理幼螨、若螨存活率以及另2个浓度处理3个螨态的存活率都显著下降.在非选择性试验条件下,用这3个浓度的提取物处理叶片饲养的桔全爪螨雌螨繁殖量显著减少,寿命也显著缩短.在田间用这3个浓度的提取物在2 0d内连喷2次,桔全爪螨卵、幼螨和若螨的存活率都低于对照,干扰作用控制指数分别为0 5 18、0 . 2 92、0 . 2 77,即对种群增长控制的效果分别为4 .8 2 %、70 . 8%、72 . 3% ,比15 %哒螨灵乳油2 0 0 0倍处理更有效控制桔全爪螨的田间种群.田间试验结果还表明,提取物处理的叶片比对照和哒螨灵处理的浓绿。

薇苷菊乙醇提取物对褐稻虱种群的干扰作用

应用扩展的均匀设计与生命表技术，评价薇苷菊乙醇提取物使用浓度、次数对褐稻虱种群的干扰作用。结果表明，薇苷菊乙醇提取物对褐稻虱成虫具有强烈的产卵驱避作用，干扰作用控制指数IIPC为0.300～0．500；对褐稻虱各龄幼虫具有较好的毒杀效果。同时建立干扰效果与这些因素之间的回归模型，其使用浓度与次数的不同组合，大多可将褐稻虱种群趋势指数，降至1．00以下，使用次数对防治褐稻虱的干扰作用大于使用浓度。

非嗜食植物提取物对桔全爪螨产卵的驱避性测定

The oviposition repellency of the alcohol extracts from 50 species of non-preferable plants and azadirachtin against citrus red mite (Panonychus citri) was determined using laboratory bioassays.In choice tests,the extracts from 42 of the 50 plant species and 1% azadirachtin (2000×) significantly reduced oviposition 1d after treatment.The repellency effect of the extracts from the 42 plant species was better than that of azadirachtin.Mikania micrantha extract had the best result,with an Interference Index of Population Control (IIPC) of 0.087 1 d after treatment,and significantly reduced oviposition for 9 d,while the extracts from Sesbania cannabina,Allium tuberosum,Paederia scandens,Duranta erecta and Dicranopteris pedata also had good effects,with an oviposition repellency of over 70% 1 d after treatment,and significantly reduced oviposition for 4～6 d.The effect became weaker as time went on.None of the extracts showed significant oviposition attraction.