Indoor Inhibitory Effect Of Tea Saponin On Cylas Formicarius And Field Control Effect

In order to expand the insect resistance spectrum of tea saponin,explore its control effect on sweet potato weevil and explore the potential of tea saponin as an insecticide for pest control.In this paper,Y-type olfactometer was used to measure the olfactory repellency rate of Cylas formicarius to tea saponin,selectivity method was used to determine the feeding repellency rate of Cylas formicarius to tea saponin,selectivity method was used to determine the antifeedant rate of Cylas formicarius to tea saponin-containing food,and artificial diet method was used to determine the development duration and adult longevity of sweet potato weevil under the influence of tea saponin.Field experiments were carried out to study the control effects of tea seed bran and tea saponin on Cylas formicarius.The results show that:1.Tea saponin did not produce significant olfactory aversion or olfactory attraction to the Cylas formicarius.However,tea saponin had a feeding avoidance effect on the sweet potato weevil.The feeding avoidance rate increased with the increase of tea saponin concentration,and the 6-hour avoidance rate was higher than that of 1-hour.At 6-hour,the feeding avoidance rates of 0.25%,0.5%,1.0%,5.0%,10.0%,20.0%were 40.67%,58.14%,77.77%,88.23%,95.00%and 97.65%,respectively2.Tea saponin had significant antifeeding effect on the Cylas formicarius,and the longer the feeding time was,the higher the antifeeding rate was.At 72 hours,the antifeeding rates of 0.25%,0.5%and 1.0%were 52.03%,63.01%and 67.54%,5%,10.0%and 20.0%respectively,97.14%,96.42%and 98.57%.3.The duration of eggs,larvae and pupae of Cylas formicarius was shortened under the influence of tea saponin,and the higher the concentration,the shorter the development duration,and it would lead to death.Under the action of 1.0%tea saponin,the larval development duration was the shortest,which was 4.01 days shorter than that of the control,and the larval mortality rate was the highest(53.33%).In addition,the longevity of adults was significantly shortened by 23.67 days compared with the control group after tea saponin intake.4.The effect of Tea Seed Bran and tea saponin on controlling weevil was significant.The control effect of tea seed bran root spraying was 98.46%,and that of tea seed bran root irrigation was 87.49%,which was slightly lower than that of tea seed bran,but there was no significant difference between them5.Tea saponin can enter the root tuber of sweet potato,and can be detected in the 1-1.5 cm part of the epidermis and epidermis,but not in the 1.5-3 cm partThe results of this study showed that tea saponin had a variety of effects on the behavior and development of Cylas formicarius,and had a good control effect.The conclusion of this study could be used to control and carry out more in-depth research on the control of Cylas formicarius,which not only expanded the insect resistance spectrum of tea saponin,but also excavated its potential properties,as well as to develop tea saponin the future.Insecticides provide ideas and theoretical basis.