摘要
为明确玉米大豆间作对草地贪夜蛾Spodoptera frugiperda发生为害及产量的影响,于2023年在广西壮族自治区南宁市设置两季的玉米单作、大豆单作、玉米2行大豆4行间作和玉米4行大豆4行间作共4种种植模式,采用直接观察法调查不同种植模式下田间草地贪夜蛾的百株虫量和玉米被害株率,并测定玉米和大豆的产量.结果表明:2023年草地贪夜蛾在下半年(9月1日-10月27日)比上半年(3月20 日-5月15日)发生更加严重.相较于玉米单作种植模式,上半年玉米2行大豆4行间作和玉米4行大豆4行间作种植模式的草地贪夜蛾百株虫量分别降低41.01％和41.21％,玉米被害株率也显著降低,土地当量比分别为1.35和1.26;下半年玉米2行大豆4行间作和玉米4行大豆4行间作种植模式下的草地贪夜蛾百株虫量分别降低10.11％和6.82％,玉米被害株率无显著差异,土地当量比分别为1.50和1.43.表明在草地贪夜蛾虫口密度相对小的情况下,玉米大豆间作能显著减轻草地贪夜蛾的发生为害;在产量上,玉米2行大豆4行间作和玉米4行大豆4行间作2种间作模式均表现为增产,前者优势更大.
Abstract
To clarify the effect of maize-soybean intercropping on the occurrence and damage of fall ar-myworm,Spodoptera frugiperda,as well as the yield,a study was established during two growing sea-sons in Nanning,Guangxi Zhuang Autonomous Region,in 2023.The experimental treatments included monocultures of maize and soybean,and intercropped systems with two rows of maize and four rows of soybean,and four rows of maize and four rows of soybean.The number of S.frugiperda larvae per 100 plants and maize damage rate were surveyed in the field by direct observation,and yields of maize and soybeans were measured.The results indicated that during the experimental period in 2023,the oc-currence of S.frugiperda was more severe in the second half of the year(September 1st to October 27th)compared to the first half(March 20th to May 15th).Compared to monoculture maize,the num-ber of S.frugiperda larvae per 100 plants in the intercropped systems with two rows of maize and four rows of soybean,and four rows of maize and four rows of soybean decreased by 41.01％and 41.21％,respectively.The maize plant damage rate was also significantly reduced,with land equivalent ratios of 1.35 and 1.26,respectively,in the first half of the year.In the second half of the year,the number of S.frugiperda larvae per 100 plants in the same intercropping systems decreased by 10.11％and 6.82％,re-spectively.There was no significant difference in the maize plant damage rate,and the land equivalent ratios were 1.50 and 1.43,respectively.This study suggested that under relatively low population densi-ties of S.frugiperda,maize-soybean intercropping can alleviate the occurrence and damage of S.frugi-perda.In terms of yield,both intercropping systems with two rows of maize and four rows of soybean,and four rows of maize and four rows of soybean showed increases,with the former demonstrating a greater advantage.
基金项目
国家重点研发计划(2021YFD1400700)
财政部和农业农村部:国家现代农业产业技术体系建设专项(CARS-02)
维普
万方数据