Effects Of Aqueous Extracts Of Astragalus Membranaceus (Fisch.)Bge. On Plants, Insects And Fungi

Astragalus membranaceus (Fisch.) Bge. is a species of Leguminosae. Its roots are Chinesetraditional herb. The market requirement of the herb is quite large. As Chinese traditional medicinalmaterials, it's better to be harvested in 3-4 years after being planted. But now it is harvested in only 1-2years, it has bad influence on the quality of the medicinal materials. How to develop the value ofeco-economy and improve the investment return to ensure enough planting cycle and the quality ofmedicine, reduce the pollution ofA. membranaceus (Fisch.) Bge. planting, is becoming a question in theway of A. membranaceus (Fisch.) Bge. production.Based on the former researches, studied the allelopathy of the leaves,stalk and pericarp of A.membranaceus (Fisch.) Bge..Studied the influences on germination of plants, death rate of insect larvaand toxicity to fungi. Supplied theoretical basis for A. membranaceus (Fisch.) Bge. developing, such asactive substances researching, eco-economy developing, etc.By the studies on the influences of its aqueous extracts on plants, the results show the aqueousextracts of A. membranaceus (Fisch.) Bge. has allelopathy activity on other plants and itself, thetreatment must last enough time. The aqueous extracts of pericarp has the highest allelopathy activity ongermination of plants, leaves' in the middle, the stalk's has lowest activity. Its aqueous extracts of leavescan anti-germinate different plants. The germinating rate of Cruciferae, Leguminosae, Sterculiaceae andLiliaceae is 0. The germinating rate of Cucumis sativus L., Cosmos bipinnatus, and Zea mays Linn. isnot 0, but the value of germinating index, and activity index all descended. The allelopathy activity hasno obvious differences among the materials of the different planting years, different waterlogging timesand different temperatures. Solute potential has some influences on their germination rate, but theirinfluence is small.By the researches of allelopathy activity of its aqueous extracts on insects, found out it has obviousallelopathy activity on larvae of Tenebrio molitor Linnaeu. Waterlogged its larvae with pericarp, thedeath rate is 50ï¼…in 3rd day, and keep touching with the aqueous extracts of its leaves, the death rate is55ï¼…in 3rd day. Feeded them the food waterlogged with different aqueous extracts, it resulted in thelarva death, too. The death rate can be 45ï¼…, and the ecdysis rate be only 25ï¼…of the CK with thetreatment of its aqueous extracts of pericarp. But feeded them the food waterlogged with differentaqueous extracts, the ecdysis rate are higher than that of the CK. In the studies on the toxicity of its aqueous extracts on fungi, found that there can be selectivity inthe toxicity on fungi. By the treatment on four Aspergillus (Mich.) Link strains and three PenicilliumLink strains with its aqueous of the leaves, stalks and pericarps, found the aqueous extracts ofpericarp has some toxicity activity on Aspergillus penicilloides Speg, P. purpurogenum and P.corylophilum.