Study On The Repellent Effect Of Different Plants And Extracts On Drosophila Melanogaster

Blueberry is a new fruit that combines nutrition and health functions.It has good economic benefits and high nutritional value.At present,blueberry is the main cash crop in many areas of Guizhou Province and has a good market development prospect.At the end of the 20^thcentury,Guizhou Province began to introduce and plant blueberries on a large scale.However,with the continuous expansion of blueberry planting scale,the occurrence of pests and diseases is becoming more and more serious.Drosophila melanogaster is one of the main borer pests in the mature stage of blueberry fruit,which seriously affects the quality and yield of blueberry.Therefore,the prevention and control of Drosophila melanogaster has become the main technical difficulty of each blueberry base.In this paper,20 kinds of non-host plants were used to measure the olfactory response of Drosophila melanogaster adults.After screening out the plants with repellent effect,using Soxhlet extraction method to extract the plant extracts and then measure the olfactory response of Drosophila melanogaster adults.At last,the GC/MS analysis was performed on the three plant extracts with the best repellent effect,and the repellent effect was verified further.This study identified the repellent effect of plants and their extracts on Drosophila melanogaster adults,and screened out the main chemical components.It is hoped that it can provide some research foundation for the development of biological pesticides for the prevention and control of Drosophila melanogaster in the future.The main findings are as follows:1.The repellent effect of 20 non-host plants on drosophila melanogaster adultsAccording to the repellent rate,the repellent effect of 20 non-host plants on female and male Drosophila melanogaster adults can be divided into three categories.In the first category,the average repellent rate is more than 30%,and the repellent activity level is II.This kind of plant has the best repellent effect,and including six plants.In the second category,the average repellent rate is less than 20%,and the repellent activity level is I.This kind of plant also has some repellent effect,but it is lower than the first category,and including eight plants.In the third category,the average repellent rate is less than 0.This kind of plant has no repellent effect on Drosophila melanogaster adults,and including six plants.2.The repellent effect of different plant extracts on drosophila melanogaster adultsCompared with natural plants,plant extracts have better repellent effect on Drosophila melanogaster adults.There was no significant difference in olfactory response of female and male Drosophila melanogaster adults to the same plant extract.Six plant extracts have strong repellent effect,and the average repellent rate of female and male Drosophila melanogaster adults was more than 50%.The order of average repellent rate of six plants was as follows:Artemisia argyi>Coriandrum sativum>Nicotiana tabacum>Allium sativum>Artemisia carvifolia>Tagetes patula.Coriandrum sativum,Nicotiana tabacum and Artemisia argyi plant extracts had the best repellent effect,and the repellent rate was as high as 80%.3.Principal component analysis of three optimal plant extractsAccording to the GC/MS analysis of Coriandrum sativum,Nicotiana tabacum and Artemisia argyi plant extracts.It was found that the chemical composition and relative content of the three plant extracts were very different.They are mainly aromatics,terpenes,hydrocarbons,esters,amides,and ketones.38 chemical constituents were isolated and identified from the Artemisia argyi extract,The relatively higher components were coumarin?37.27%?,phytol?9.98%?and oleamide?9.73%?.39 chemical constituents were isolated and identified from the Coriandrum sativum extract,The relatively higher components were oleamide?25.65%?,phytol?20.02%?and neophytadiene?5.6%?.20 chemical constituents were isolated and identified from the Nicotiana tabacum extract,The relatively higher components were 4,8,13-Duvatriene-1,3-diol?37.49%?,nicotine?15.30%?and oleamide?12.34%?.4.Comparison of the repellent effect of main component of plant extracts17 compounds with high relative content in 3 plant extracts were selected to test the repellent effect of Drosophila melanogaster adults.It was found that the olfactory response of Drosophila melanogaster adults to different compounds was different.Four compounds have no repellent effect on Drosophila melanogaster adults,which are attractive,The other 13 compounds have certain repellent effect on Drosophila melanogaster adults.However,docosanethiol,benzenamine and nicotine had the best repellent effect,and the repellent rate was over 80%.