长孔点肋甲螨发生消长的研究

STUDIES ON THE POPULATION DYNAMICS OF PUNCTORIBATES LONGIPOROSUS BALOGH

长孔点肋甲螨主要在稻桩内越冬。雨水对该螨的冲刷作用可达80%。不同耕作措施对该螨的发生有很大影响,该螨在不同耕作田内的发生量为:免耕田>旱旋田>水旋田>旱旋水耙田>深耕田。该螨在不同水稻品种上的发生量也有差别,杂交稻(汕优63)上发生的螨量比粳稻(花寒早)上要高出20%。此外,该螨在7月上旬水稻分蘖期发生量达到高峰。

The population of Punctoribates longiporosus Balogh,a species ofMycobatidae abundant on paddy rice since 1970s in Sichuan and JiangsuProvinces,mainly overwinters in rice stubbles.80% of the mite pests can be washed away by rainfall.Its population density varied with dif-ferent farming systems.The mite density sequence in the fields withdifferent cultivations are as follows,non-tillage field>dry rotary-culti-vated field>water rotary-cultivated field>dry rotary-cultivated+wa-ter-harrowed field>deep ploughed field.There are also differences be- tween the mite densities on different rice varieties.The mite populationin hybrid rice(Shun You 63)field is 20% higher than that innon-waxy rice(Hun Han Zao)field.The density peak occurrs in theearly July.