玉米象〔Sitophilus　zeamais　(Mostchulsky)〕对小麦和玉米的危害研究

A Study on the Characteristic Harmfulness of Sitophilus zeamais (Motschulsky) to Wheat and Maize

本文介绍了玉米象〔Ｓｉｔｏｐｈｉｌｕｓｚｅａｍａｉｓ（Ｍｏｓｔｃｈｕｌｓｋｙ）〕在河南省农户家庭中危害储藏小麦（ＴｒｉｔｉｃｕｍａｅｓｔｉｖｕｍＬ．）和玉米（ＺｅａｍａｉｓＬ．）的发生规律及生活习性。玉米象在河南省每年发生４－５代，从四月上旬开始活动，七至九月份为活动高峰期，十月底进入越冬期。对小麦，在刚收获（七月份）和翌年五月开始进入玉米象危害期；对玉米则于翌年五月进入危害期。小麦和玉米经过十三个月的储藏，虫蛀率分别高达４５．６％和７０％；损失率分别达１６．５％和１８．５％，可见，玉米象危害之严重。结果表明，小麦和玉米的虫蛀率（Ｘ）和重量损失率（Ｙ）之间呈直线关系，回归方程为：小麦ｙ＝０．４３４２ｘ－２．３８５８（ｒ＝０．９９１７）；玉米ｙ＝０．２６２５ｘ＋０．０２９６（ｒ＝０．９９７０）。在一般情况下，相同的虫蛀率时，小麦的损失率大于玉米。结果表明，玉米象成虫虫口密度（Ｎ）与小麦虫蛀率（Ｘ）之间呈逻辑斯蒂曲线关系，即Ｎ＝３０００１＋ｅ４．２４９－０．０７２ｘ（ｒ＝０．

The habit and charateristics of living and the pattern of occuring were studied on Sitophilus zeamais (Motsch.) which infested wheat and maize stored at the store houses of farmers in Henan province, P. R CHINA. There were 4 and 5 generations in each year. The development of S. zeamais started in the middle of April. The infestation reached the high peak from July to September, and at October they got into in the winter stage .The infestation period of wheat by them was July ,just harvest time. That of maize was May of next year. When wheat and maize were stored up to 13 monthes, the infested rates were 45.6% and 70.0%, respectively, the weight loss rates were 16.5% and 18.5%, respectively. The results showed that the relationship between the infesting rates (X) and the weight loss rates (Y) was linear ,say ,wheat: Y=0.4342 X-2.3858;maize: Y=0.2625 X+0.029. The relationship between infesting rates (X) of wheat and the population density (N) ofS. zeamais adults was a logistic curve: