| In order to understand the resistance of main soybean varieties in Yanbian Prefecture to Tetranychus truncatus,and screen out high-efficiency acaricides,12 main soybean varieties in Yanbian Prefecture were used as materials.The relationship between the content of main nutrients and the occurrence of Tetranychus truncatus was analyzed by measuring the content of main nutrients in three periods of different soybean varieties.The survival conditions of Tetranychus truncatus were simulated to establish the breeding model of Tetranychus truncatus in 12 different soybean varieties Based on the laboratory and field experiments,two effective acaricides against Tetranychus truncatus were selected.The results are as follows:There were significant differences in the resistance of 12 soybean varieties to Tetranychus truncatus,among which the highest resistance was Henong 61 and Henong 69,while the lowest resistance was Henong 75 and Suinong 36.The contents of reducing sugar and starch were positively correlated with the occurrence of Tetranychus truncatus.Among them,the contents of reducing sugar and starch were significantly positively correlated with the occurrence of Tetranychus truncatus at flowering and pod setting stage,and the contents of soluble protein were also significantly positively correlated with the occurrence of Tetranychus truncatus at seed filling stage.There were significant differences in the growth,development and reproduction of Tetranychus truncatus among different soybean varieties.The lower or smaller the developmental duration,survival rate of nymphs,life span of adult mites,fecundity of female adult mites,intrinsic growth rate,net proliferation rate and peripheral growth rate,the more inhibitory effect on the growth,development and reproduction of Tetranychus truncatus.For example,soybean variety Henong 69 could inhibit the growth,development and reproduction of Tetranychus truncatus On the contrary,Jiyu401 inhibited the growth and development of Tetranychus truncatus.The longer the population doubling time and average generation duration were,the worse the adaptability of Tetranychus truncatus on soybean varieties was,and the worse the adaptability of Tetranychus truncatus on Henong 69 was.On the contrary,the stronger the adaptability was,and it was on Jiyu 401 the more adaptable you are.Among the 9 insecticides used in the experiment,6 insecticides with better efficacy were selected by the method of Petri dish leaf plate in the laboratory,and then3 insecticides with better efficacy were selected by pot experiment in greenhouse.Finally,avermectin was selected as the best insecticide with field control efficacy of96.16%,followed by bifenthrin with field control efficacy of 93.26%.Among the 12 soybean varieties,Henong 61 had the best resistance to mites,followed by Henong 69.The survival rate,fecundity,intrinsic growth rate,net value increment rate and weekly growth rate of nymphs of Henong 69 were lower than those of other main varieties,and the average generation cycle and population doubling time were longer than those of other varieties,followed by Henong 61.For the control of Tetranychus truncatus,Henong 69 and Henong 61 were the best choice.Abamectin is the first choice of insecticides in the occurrence of Tetranychus truncatus. |
