对悬浮离心法回收昆虫病原线虫方法的改进

AN IMPROVEMENT OF CENTRIFUGAL FLOTATION METHOD TO RECOVER ENTOMOPATHOGENIC NEMATODE FROM SOIL

本文对Ｓａｕｎｄｅｒｓ的悬浮离心回收线虫法进行了改进研究。保留第１次离心后上清液中含有的线虫，结果使小卷蛾线虫的平均回收率由３２．２％上升到６０．２％；离心处理对线虫的存活率及其对害虫的侵染率没有显著影响，但鞘的保持率有所降低。用浓度为２００ｇ／Ｌ盐液替代了浓度为４５４ｇ／Ｌ的糖液，对线虫回收率无影响。

This paper studied on the improvement of Saunders centrifugal flotation metho d to recover nematode from soil. The nematodes in the supernatant liquid from t he first spinning was counted. As a result the averaged recovery rate of Stei nernema carpocapsae rose from 32.2% (by Saunders method) to 60.2% (by the i mproved method). No remarkable adverse effect on nematode survival and infectiv ity to Carposina nipponensis larvae was observed after centrifugal treatmen ts; but the rate of nematode with cuticles was slightly reduced. The same reco very rate was obtained by using salt solution (200 g/L) instead of sucrose solut ion (454g/L) as flotation agent. The cost of centrifugal procedure by the impr oved method was reduced.