关键词: 草本科植物, 根际土, 放线菌, 代谢产物

Abstract: The aim of this study was to investigate the effects of temperature on the rate of rhizosphere actinomycetes and the activity of actinomycetes in eight Chinese herbal medicine plants in Yuzhong campus of Northwest Minzu University,and to provide a preliminary study on the follow-up actinomycete screening.The glycerol arginine agar medium containing 75 μg/mL potassium dichromate and 2 μg/mL penicillin was used to pretreat the five different temperatures of 23,60,80,100 and 120 ℃.The effects of temperature on the number and species of actinomycetes were studied by plate coating method.The results showed that the effects of temperature on the number and species of actinomycetes were qualitatively detected by seven kinds of screening medium,and the physiology of functional enzyme producing bacteria was further explored by biochemical testing.The results showed that there were 9 strains of actinomycetes in 18 strains of actinomycetes,and the number and species of actinomycetes were different in different soils at different temperatures by 23,60,80,100 and 120 ℃.Amylase production,16 strains of protease,16 strains of urease,18 strains of catalase,12 strains of polyoxyethylene sorbitan monolaurate,14 strains of polyoxyethylene sorbitan fatty acid Esterase,7 strains of polyoxyethylene sorbitan monooleate,5 strains of tryptophanase and 5 cellulases.The different types of actinomycetes were different.The results showed that the activities of amylase,protease and esterase were an important source of enzyme,and the number of actinomycetes increased with the increasing of pretreatment temperature.The species of actinomycetes at different temperatures had no correlation with temperature,but the specific temperature will be used to screen specific bacteria,that is,some bacteria have a certain selectivity to temperature.

Key words: Herbaceae plants, Rhyme soil, actinomycetes, metabolite