玉米抗螟性室内鉴定新技术──虫粪圈法

The Frass-ring Index to Evaluate the Maize Plant Resistance to Asian Corn Borer in the Laboratory

室内抗螟性离体鉴定，采用虫粪圈法测定根据粪圈系数大小确定玉米抗螟性的强弱，凡系数大，幼虫发育良好，虫体重，且田间心叶期鉴定验证，食叶级别亦高，抗螟性差．系数与幼虫体重、与田间食叶级别均是显著正相关。比室内离体鉴定幼虫秤体重法，简便易行．不需要电子天平，更具有广泛的实用性．

The maize plant resistance to Asian corn borer,Ostrinia furnacalis(Guenee),was evaluated by using the frass-ring index (FRI)after the larvae feeding on thelyophilized diet plugs absorbed with juice of whorl tissues of maize seeding for 10 days.The FRI was higher in the treatments with juice of susceptible maize than in that of resistant ones because of larger larvae developed and more frass produced surrounding theplugs absorbed juice of Susceptible materials. The results by the bioassay were significantly or high significantly positive correlation with that obtained from the field evaluation. This technique was more simple and practical than the larval weight method.