不同鲜食玉米品种的抗螟性比较

Comparison of Borer Resistance of Different Fresh-eating Corn Varieties

为有效实施玉米害虫综合治理,对玉米品种之间的抗螟性差异进行比较,筛选具有抗螟性特征的玉米品种。在自然感虫状态下采用平行跳跃法分别记录玉米螟在玉米苗期、穗期、花粒期的危害状况,对17个鲜食玉米品种进行抗螟性鉴定,并对采用花叶指数测定玉米苗期抗螟性的可行性进行分析。结果表明,不同鲜食玉米品种百株受害率的动态变化规律基本一致,均在收获时受害株率达到最高峰。苗期抗螟性表现为高抗的玉米品种有4个:甜嘉糯1号、云糯4号、天紫23号、黑糯1号;穗期抗螟性表现为高抗的玉米品种有2个:甜嘉糯1号、天紫23号。花粒期云糯4号百株蛀孔数最低,为79.0个,夏王超甜百株蛀孔数最高,为243.3个。花叶指数与平均食叶级别极显著相关,花叶指数可作为鉴定玉米抗螟性的重要指标。甜嘉糯1号和天紫23号的抗螟性较好,可在螟虫发生危害严重的区域种植。

In order to effectively implement integrated control of corn pests,the differences of resistance to borer among corn varieties were compared to screen borer-resistant corn varieties.Parallel jump method was used to record the damage of corn borer at seedling stage,ear stage and flower-grain stage of corn under natural susceptibility.17 varieties of fresh-eating corn were identified for borer resistance,and the feasibility of mosaic index to determine borer resistance of corn at seedling stage was analyzed.The results showed that the dynamic changes of damaged ratio per 100 plants of different fresh-eating corn varieties were basically the same,and the damaged ratio reached the peak at harvest time.At seedling stage,there were four varieties(Tianjianuo 1,Yunnuo 4,Tianzi 23 and Heinuo 1)with high resistance to borers.At ear stage,there were two varieties(Tianjianuo 1 and Tianzi 23)with high resistance to borers.At flower-grain stage,the lowest number of borers per 100 plants was inYunnuo4(79.0),and the highest borer number of 100 plants was in Xiawangchaotian(243.3).The correlation between mosaic index and average leaf-eating grade was extremely significant.Mosaic index could be used as an important index to identify the resistance of corn to borers.Tianjianuo 1 and Tianzi 23 had better resistance to borers and could be planted in areas where borers seriously occurred.