Toxic Reaction Of Trialeurodes Vaporariorum To Toxic Macrofungi

Trialeurodes vaporariorum Westwood is a serious threat to many kinds of fruits and vegetables in China.The study identifies the known macrofungi collected in Liaoning Province,Henan Province and some areas of Xinjiang;breeds the mycelia of the tested toxic macrofungi by submerged fermentation to produce crude toxin with insecticidal effect,and conducts toxicity tests on the adults and 1st instar nymphs of whitefly in greenhouse.We obtain the ideal insecticidal effect,the findings are the following:1.Among identified 116 macrofungi,including 23 toxic macrofungi and 93 non-toxic macrofungi.The paper chooses the above 23 toxic macrofungi to manufacture the crude toxin,and tests pre-experiments for the adults of Trialeurodes vaporariorum.The experimental results show that 23 toxic macrofungi have toxic effects on them,in which the crude toxins of 5 macrofungi,Amanita pantherina(DC.: Fr.)Schrmm.,Amanita virosa Lam.: Fr.,Anellaria semiovata,Amanita subjunquillea,and Russula emetica(Schaeff.: Fr.)Pers.ex S.F.Gray,all have higher lethality(up to 90 %)to the adults of Trialeurodes vaporariorum.2.The crude toxin of the above 5 toxic macrofungi are used to kill the adults of the Trialeurodes vaporariorum.The results show that their 24-hour half lethal concentrations are 48.469mg/mL,40.830mg/mL,51.861mg/mL,42.208mg/mL and 46.419mg/mL,respectively,in which the crude toxin of Amanita virosa has the best killing effect on the adults of Trialeurodes vaporariorum.3.The crude toxin of the above 5 toxic macrofungi are used to kill the 1st instar nymphs of the Trialeurodes vaporariorum.The results show the 24-hour semi-lethal concentrations of the crude toxin are 40.955mg/mL,38.414mg/mL,44.066mg/mL,37.552mg/mL and 46.671mg/mL,respectively,in which the crude toxin of the Amanita subjunquillea has the best toxicity to the 1st instar nymphs of Trialeurodes vaporariorum.4.We also test the stability for light and heat of the crude toxins of 5 toxic macrofungi,finding 3 strains,Amanita pantherina,Amanita virosa,and Amanita subjunquillea,have better stability.The crude toxins of the above 3 toxic macrofungi are paired,the ratios of each group being 1:1,2:1,and 1:2,respectively,to obtain 9 mixed crude toxins,and use them to do the 24-hour toxicity test on the adults of whitefly in greenhouse.The results show that the 9 groups of mixed crude toxins own different degrees of additive effect for the poisoning,of which mixed crude toxin with the best insecticidal effect is mixed crude toxin of the Amanita virosa and Amanita subjunquillea(the ratio of 2:1),and its half lethal concentration for tested adults is 36.842mg/mL and its co-toxicity coefficient 112.032;For the first instar nymphs tested,the 24-hour half lethal concentration is 34.113,and its co-toxicity coefficient 111.761.However,the LC50 value of the mixed crude toxin to Danio rerio at 72 h is 2222mg/mL,indicting it belongs to low toxicity.5.The co-control of mixed crude toxin and sticky yellow plate on Trialeurodes vaporariorum is not as strong as cypermethrin of 1000 times liquid,but its killing is obviously better than that of mixed crude toxin alone.The paper's purpose is to develop a highly effective insecticide from toxic macrofungi for killing Trialeurodes vaporariorum and friendly for environment,to make up for the environmental pollution and food safety problems caused by the chemical pesticide residues and difficult degradation.