The Study On Toxic Effect Of Tenebrio Molitor L. By Composite Biological Extracts

Tenebrio molitor L. is one of the dominant storage pests which lives in warehouse. Theyeat whole grains、bran and fruit peel and many other things. They especially damage to thenatural fibers like braided fabric of rush mat and reed. It has caused great economic loss forthe rush mat of import and export commodities. This paper chose the macrofungus and plantsof Liaoning province and combined with the result of stability tests, and then mixed thescreened macrofungus liquid deep fermentation extracts and plant ethanol extracts by acertain proportion. Finally a new biological pesticide mixture has got—composite biologicalextracts. The result shows that：1. Using17families38species macrofungus’ liquid deep fermentation extracts toTenebrio molitor L. on toxicity test, chose the insecticidal efficiency achieved90%and aboveto do the stability tests. Finally, it screened2kinds of macrofungus with better stability andhigher insecticidal activity to Tenebrio molitor L.: Lepiota helveola Bres and Amanitapantherina (Dc.:Fr.) Schrmm.2. Using11families31species plant ethanol extracts to Tenebrio molitor L. on toxicitytest, chose the insecticidal efficiency achieved90%and above to do the stability tests. Finally,it screened2kinds of plants with better stability and higher insecticidal activity to Tenebriomolitor L.: Artemisia capillaris Thunb and Mentha canadensis L.3. Mixed the screened Lepiota helveola Bres’s liquid deep fermentation extracts andAmanita pantherina (Dc.:Fr.) Schrmm’s liquid deep fermentation extracts with Artemisiacapillaris Thunb’s plant ethanol extracts and Mentha canadensis L’s plant ethanol extractsby proportion of100:1. The maximal co-toxicity coefficient is the group of Lepiota helveolaBres’s liquid deep fermentation extracts mixed Artemisia capillaris Thunb’s plant ethanolextracts by proportion of100:1. The Co-toxicity coefficient to the6thinstar larvae of Tenebriomolitor L. is120.69; to adult stage of Tenebrio molitor L. is120.77.4. The LC50of the composite biological extracts to Danio rerio on toxicity test is342.3mg/L which belongs to low toxicity. Stomach toxicity is the main and obvious way toTenebrio molitor L.