鲁西南三种栽培模式棉田盲椿象的发生与危害

Occurrence and Damage of Mirids in Cotton Fields under Three Cultivation Types in Southwest Shandong Province

比较研究了鲁西南直播棉、蒜套棉、麦套棉三种种植模式棉田中盲椿象的种群数量和盲椿象对产量的影响。结果显示:两种晚播棉——蒜套棉和麦套棉的盲椿象种群数量显著高于直播棉,其中棉田盲椿象发生高峰期,蒜套棉和麦套棉未防区盲椿象百株虫量分别为直播棉未防区的4.56倍和4.45倍;8月份之前化学防治能够有效地控制棉田盲椿象的种群数量,盲椿象发生高峰期,防治区和未防治区的种群数量均在防治指标(20头/百株)之上;棉田播种时间越晚,减产幅度越大,麦套棉、蒜套棉和直播棉的减产幅度分别为38.4%、27.5%、22.1%。

The mirid populations and their effects on cotton yield were studied under the cultivation pattern of spring cotton, cotton interplanted with garlic and wheat in southwestern of Shandong Province. The results in- dicated that the population density under the pattern of cotton interplanted with garlic and wheat were significant- ly higher than that in spring cotton fields, and the occurrence peak of the two formers were 4.56 and 4.45 times of the latter＇ s respectively. Chemical control could well depress the mirid populations before August ; however, the mirid populations in the control and non -control cotton fields were all more than the control threshold （20 individuals per 100 plants） at the occurrence peak, especially in the interplanted cottons. The later the cotton planted, the more the yield loss was. The yield loss percentage of the cotton interplanted with wheat and garlic and the spring planted cotton were 38.4%, 27.5% and 22.1% respectively.