棉铃虫致病菌BT－931菌株的应用研究

STUDIES IN THE APPLICATION OF DISEASE-PRODUCING BACILLUS THURINGIENSIS 931 STRAIN TOHELIOTHIS ARMIGERA

１９９２－１９９３年，作者从菏泽、聊城棉田采集的自然罹病死亡棉铃虫幼虫体内，分离到２个较高毒效的Ｂｔ菌株，编号为ＢＴ—９３１和ＢＴ—０２１，经室内毒力测定和田间药效试验表明，防效及保蕾效果接近或超过化学农药，菌药混剂３—５天平均防治效果达８７．０－９１．６％，增效作用显著。经１９９４年大田防治示范表明，利用ＢＴ—９３１菌剂。配合化学农药防治棉铃虫，具有成本低、保护天敌、持效期长、增产效益高等优点。本研究对菌剂的田间应用技术进行了试验示范。

In 1992～1993 two strains of higher toxical Bacillus thuringiensis were isolated from diseased larvae of Heliothis armigera collected in Heze and Liao cheng by us, numbered BT 931 and BT 921. The results of indoor bioassay on the on onfectivity and field control tests showed that the eontrol effect against Heliothis armigera and the protection effect for cotton flowef buds approached exceeded farm chemicals. By 3-5days,tho aver age control effect of mixture perscription of germ and pesticide Was 87.0-91.5% its synergistism was marked. The result of a large area field control demonstration in 1994 showed that thaking use of BT-931 germ dose and cooperating to use pesticide against Heiothis armigera had the merist of low cost,prttecting beneficial insect. Long effect and high ben and high ben efit of inerease production etc. We had proceeded the tests and demonStyations of field spplication technique of bacteria preparation yet.