华南双季稻区早稻收割和晚稻移栽对褐飞虱种群动态的影响

为了阐明华南双季稻区早稻收割和晚稻移栽对褐飞虱种群动态的影响,2011年在韶关市采用田间调查与卵巢解剖的方法研究了双季早稻、双季晚稻、田埂杂草上褐飞虱的种群动态及虫源性质。结果表明:早稻收割后,早稻上大量的褐飞虱1～2龄若虫被淘汰,3龄以上若虫及成虫不断转移扩散致使附近晚稻秧田和杂草上褐飞虱虫量突增;晚稻移栽之后,杂草及晚稻秧田的褐飞虱又向新插秧的晚稻进行转移,但成为有效虫源的虫量较少,因此,早稻收割和晚稻移栽对褐飞虱种群动态造成了极为不利的影响,晚稻秧田和田埂杂草可作为褐飞虱转移过程中的流动栖息场所,在褐飞虱虫量转移中起着一定的作用。

Effect of early rice harvesting and late rice transplanting on population dynamics of brown planthopper, Nilaparvata lugens (St(a)l) in South China double- cropping rice region

In order to illustrate the effect of early rice harvesting and late rice transplanting on the population dynamic of Nilaparvata lugens(Stl)(BPH) in South China double-cropping rice region,the population dynamics and characteristics of the pest between the double-cropping early-season rice fields,double-cropping late-season rice fields and ridge weeds in Shaoguan in 2011 were studied through systematic field survey and female ovarian maturity.The results showed that a large number of 1st-2nd instars nymphs of BPH were eliminated in early rice fields after double-cropping early-season rice crops harvesting in Shaoguan,while 3rd-5th instars nymphs and adult of BPH transferred in short distance to double-cropping late-season rice seedling fields and weeds,which could increase the population densities of BPH here.Small mount of BPH between the double-cropping late-season rice seedling fields and weeds migrated to the newly transplanting late rice fields after double-cropping late-season rice crops transplanting in Shaoguan.Therefore,early rice harvesting and late rice transplanting were not beneficial for the population dynamic of BPH,and the double-cropping late-season rice seedling fields and weeds played a role in the transferring process of BPH as a rest place.