水稻主要病虫害综合防治研究

A RESEARCH ON INTEGRATED PEST CONTROL ON RICE

多因子试验结果表明:水稻纹枯病、稻瘟病、稻螟粘虫稻苞虫的发生危害程度、蜘蛛数量消长、绒茧蜂茧块密度和水稻产量等,均与稻田管理措施中的水、肥、密和杀虫剂、杀菌剂的施用次数,存在显著的非线性数量关系。根据试验结果进行模拟、优化组合,获得了五套成都平原水稻主要病虫害综合防治技术措施。经田间验证从控制主要病虫的总体生态效果、技术经济投入和产出的利润分析排序表明,综防措施优于传统化学防治。与对照相比,可减少氮肥用量20～45％、杀虫剂50％以上,降低投入74.85～130.05元/hm^2;增加纯收入122.1～486.9元/hm^2。同时,综防区蜘蛛密度平均增加1.44倍;绒茧蜂茧块数提高11.61～28.90倍。

Results from multi-factor experiments showed that indices of six main rice pests which included injury levels of rice stem borers Chio suppresalis, Tryporyza incentulas indices of rice sheath disease Rhizoctonia solani and rice blast Pyricularia oryzae, population of army worm Leucaoia venalbo and parasitic bees (spp.) as well as rice yield were closely relative to each of the experimental factors which were amount of nitrogen application, density of transplanted rice seedlings, depth of irrigation water and numbers of insecticide and fungicide. Consequently, five optimal combinations of controlable measures for integrated pest control on rice have been selected by simulating. Results of analyses of data tested in fields demostrated that ecologic control effects on the pests, costs and prof its of the combinations were obviosly superior to conventional chemical control. Comparison of chemical control, the new methods reduced amount of nitrogen and pesticide applied by 20~45% and over 50% respectively, decreased tatol costs by 74.85~130.05%yuan/ hm2 and increased net return by 122.10-486.90 yuan/hm2, populations of spiders and cocoon masses of parasitic bees by 1.44 and 11.61-28.90 times respectively.