Influence of Allelochemicals on Microbial Community in Ginseng Cultivating Soil

ObjectiveTo study the influence of allelochemicals such as benzoic acid, diisobutyl phthalate, diisobutyl succinate, palmitic acid, and 2,2-bis-(4-hydroxyphenyl) propane on the microbial community of ginseng cultivating soil.MethodsSoil samples were sprayed with five allelochemicals (100 mg/L) and their mixture (20 mg/L), respectively. Carbon metabolic ability variances were analyzed by Biolog method and genetic polymorphism variance was analyzed by RAPD method. The Nei's genetic diversity index and Shannon's information index were calculated.ResultsSignificant differences in carbon metabolic activity were found between allelochemical-treated soils and control. Further analysis indicated that although the carbon-utilizing ability and genetic polymorphism of soils treated with di-isobutyl phthalate, di-isobutyl succinate, and allelochemical mixtures were lower than those of the other treatments, genetic similarities of soils treated with di-isobutyl phthalate, diisobutyl succinate, and allelochemical mixtures were much higher than those of the other treatments.ConclusionAllelochemicals significantly declined the genetic diversity and carbon metabolic activity of microorganisms in newly reclaimed forest soil for ginseng cultivation.