Study On Distribution And Chemical Control Effect Of Pests And Weeds In Maize Farmland In Tongliao Area

In view of the production reality of serious pest control,high cost and low efficiency of chemical prevention and control and widespread occurrence of pesticide damage in the process of maize production in Tongliao area,the investigation on pest and weeds and study on chemical synergistic control effects of maize field in Tongliao area were carried out in Linjiaweizi village,Tongliao Economic and Technological Development Zone,Inner Mongolia Autonomous Region in 2021.The trail was adopted large-scale comparative design taking no control of weeding and insect as the control(CK),and three treatments of weeding control and no insect control(P1),pest control and no weeding control(P2)and control of weeding and insect(P3)were set respectively to investigate the diversity of weeds and insects and the effects of chemical control in order to provide theoretical reference for rational control of maize and high-yield and efficient planting in Tongliao area.The main results are as follows:1.Diversity and occurrence law of weeds and pests in maize field in Tongliao area.There are 11 families of weeds in maize field in Tongliao area,including Gramineae,Convolvulaceae,Solanaceae,Chenopodiaceae,Amaranthaceae,Amaranthaceae,Labiatae,Compositae,oleander,Asclepiadaceae,Polygonaceae and Malvaceae.The species of Gramineae weeds account for the highest proportion of farmland weeds,weeds are divided into monocotyledonous weeds and dicotyledonous weeds,most of which are monocotyledonous weeds;there are 10 main types of pests introduced into maize field in Tongliao area,including maize borer,armyworm,maize armyworm,Spodoptera litura,small land tiger,beet armyworm,maize aphid,maize winged planthopper,double spotted firefly leaf beetle and leaf mite,and most of them are harmful to maize stems and leaves.2.Effects of chemical synergistic control on maize growth and development in Tongliao area.With the development of growth period,plant height,stem diameter,leaf area index and dry matter quality of maize in different treatments showed a single peak curve trend of first increasing and then decreasing,which were all the largest in R1period.On the whole,the agronomic characters of maize in different treatments were P3>P1>P2>CK;at different growth stages,P3 was the best and CK was the worst.P1 was slightly better than P2 at seedling stage,but P2 was slightly better than P1 at late growth stage;The change trend of antioxidant enzyme activity in the later growth stage of different treatments was P3>P2>P1>CK,and it was more obvious in silking stage.3.Effects of chemical synergistic control on maize yield and benefit in Tongliao area.The maize yield of different treatments was P3>P1>P2>CK,in which the difference between P1 and P2 was not significant and CK was the lowest and significantly different from P3.The overall performance of effective panicles,grains per panicle and 1000 grain weight of different treatments was similar to that of yield;The performance of maize production investment and economic benefits of different treatments are consistent,with P3 as the highest,P1 as the second,P2 as the third,and CK as the lowest.Among them,P3 is 555 RMB/hectare,1380 RMB/hectare and 1830 RMB/hectare higher than P1,P2 and CK respectively.