水稻品种和施肥时间对单季稻田中白背飞虱卵被寄生率的影响

Effect of rice variety and fertilization timing on egg parasitism of Sogatella furcifera in the single-cropping season rice field

为明确水稻品种和施肥时间对白背飞虱Sogatellafurcifera (Horv th)卵被稻飞虱缨小蜂Anagrusspp .寄生率的影响 ,采用产卵苗诱集法和田间双因子设计进行实验研究。与秀水 11水稻品种相比 ,协优 413品种上的白背飞虱卵块位置较高且卵块较大。诱集实验表明白背飞虱卵的被寄生率显著受用于诱集的产卵水稻品种的影响 ,在协优 413上所产卵的被寄生率(2 4% )显著高于秀水 11上的相应值 (12 % ) ,而不受由田间品种和氮肥施用时间组合而形成的诱集苗所置放的栖境条件的影响。田间种植的水稻品种对其稻株上的白背飞虱卵被寄生率的影响大于施肥时间 ,在卵高峰期 ,这种影响更为显著 ,协优413上的被寄生率 (17% )显著高于秀水 11上的相应值 (9% )。田间寄生率和诱集寄生率二者的反正弦平方根转换值间存在着极显著的直线相关。这些结果表明 。

To understand the effect of rice variety and fertilization timing on e gg parasitism of the white-backed planthopper, Sogatella furcifera (Homopte ra: D elphacidae) by parasitoids, experiments with “trap” rice plants of two varieti es (indica-japonica hybrid combination Xieyou 413 and japonica Xiushui 11) were set up in the habitats created by the combinations of the two rice varieties and fertilizations at two different dates in the single-cropping season rice plots in Hangzhou, China. The location of egg masses of S. furcifera laid in plant s of Xieyou 413 were higher and the clutch size of egg masses was larger than that o f those laid in plants of Xiushiu 11. The parasitism of S. furcifera eggs by Anagrus spp. (Hymenoptera: Mymaridae) was significantly affected by rice v arieties used as traps, but not by rice varieties and nitrogen fertilization timing in th e fie ld. The parasitism (24%) in Xieyou 413 as trap was significantly higher than tha t (12%) in Xiushui 11 as trap. The parasitism in the plants (Xieyou 413 vs X iushui 11: 1 7% vs 9%) grown in the field was more significantly influenced by rice varie ties than by fertilization timing. The results implied that rice variety was an impo rtant factor in enhancing the biocontrol of the planthopper. Additionally, the estimation of egg parasitism by trapping approach was significantly correlated with that by dissection of rice plants sampled from fields.