螺旋粉虱产卵蜡泌物对香蕉网蝽的拒食活性

螺旋粉虱产卵分泌物所圈定的叶片范围可阻碍一些植食性昆虫如香蕉网蝽的取食。本文采用叶碟法测定了螺旋粉虱产卵分泌物中的芳香酯类、酚类和烷烃类物质对香蕉网蝽5龄若虫的拒食活性。结果表明:在10mg·mL-1质量浓度下,邻苯二甲酸二丁酯表现出较强的拒食活性,其次为3,5-二(1,1-二甲基乙基)-4-羟基苯丙酸甲酯、邻苯二甲酸正辛酯和正十六烷,4,4’-亚甲基双(2,6-二叔丁基苯酚)则没有拒食活性;浓度梯度试验显示,邻苯二甲酸二丁酯对香蕉网蝽若虫的拒食活性随浓度增大而增强,拒食中浓度为0.929mg·mL-1;表明螺旋粉虱产卵分泌物中的芳香酯对一些植食性昆虫有很强的拒食活性,同时为植食性昆虫种间竞争关系提供了理论依据。

Antifeedant activities of female Aleurodicus disperses-secreted waxes against Stephanitis typica

The waxy spirals produced by female Aleurodicus dispersus during oviposition could be a chemical barrier against some herbivorous insects such as Stephanitis typica. In this paper, a laboratory leaf disc bioassay was conducted to study the antifeedant activities of aromatic esters, phenol, and hydrocarbon in the female A. disperse-secreted waxes against 5th-instar S. typica nymph. At concentration 10 mg·mL-1, the dibutyl phthalate in the secreted waxes had strong anntifeedant activity, followed by 3,5-bis (1,1-dimethylethyl)-4-hydroxy-benzenepropanoic acid methyl ester, di-n-octyl phthalate, and hexadecane, while 4,4′-methylenebis [2,6-bis (1,1-dimethylethyl)] phenol had no antifeedant activity. The antifeedant activity of dibutyl phthalate increased with its increasing concentrations, and the median antifeedant concentration against the S. typica was 0.929 mg·mL-1. The results implied that the aromatic esters from the waxy spirals exhibited significant antifeedant activity. These findings provided a new evidence for the interspecific interactions in phytophagous insects.