施用微生物菌剂对烤烟经济性状及其根际微生态变化的影响

以烤烟红花大金元为试验材料，在连作5年植烟土壤中施用微生物菌剂，发现该微生物菌剂提高了烤烟的产量、产值、均价和中上等烟比重，在一定程度上克服了烤烟的连作障碍，并初步对其可能的微生物机制进行分析。通过平板计数，发现微生物菌剂处理烤烟根际土壤的细菌、放线菌、真菌分别比对照高128．57％、191．43％、107．61％。BIOLOG 分析表明，施用微生物菌剂对烤烟根际土壤中以糖类、酚酸、氨基酸、胺类、羧酸衍生物为碳源进行生长的微生物有促进作用，且施用微生物菌剂处理的烤烟根际土壤微生物的 SIMPSON （J）指数、SHANNON （H）指数、SHANNON （H）均匀度指数、BRILLOUIN 指数、McIntosh （Dmc）指数均高于对照，表明微生物菌剂处理提高了土壤微生物功能多样性。微生物菌剂处理烤烟根际土壤中纤维素酶、多酚氧化酶、脲酶、脱氢酶和蔗糖酶活性分别比对照增加了52．44％、482．24％、16．28％、203．66％、56．40％，表明施用微生物菌剂有利于提高主要的土壤酶活性。综上所述，施用微生物菌剂改善了烤烟连作植烟土壤根际微生态，促进烟草生长，提高了烟草品质。

Effect of a Microbial Agent on Rhizospheric Microecology and Economic Traits of Flue-cured Tobaccos

Using Honghuadajinyuan （Nicotina tobaccum L.cv.）,an experimentation by adding a microbial agent to the soil for 5 consecutive years to determine the rhizospheric and economic effects on the tobaccos was conducted. The results showed that the treatment benefited the plant growth in general.It increased the yield,value and proportion of high quality tobacco.To some extent,the agent also alleviated the problems normally associated with the consecutive monoculture.The possible mechanism was,therefore,studied.The agar plate counts on the rhizospheric bacteria,actinomycetes and fungi in the soil were compared with the control to be higher by 128.57%, 191.43%,and 107.61%, respectively.BIOLOG analysis indicated that the average well color development （AWCD）of carbohydrates,phenolic acid,amino acids,amines and carboxylic acid were higher with the treatment than CK.Furthermore,the diversity indices on the microbes utilizing carbon sources,such as Simpson （J ）, Shannon index （H）,Shannon index （H）evenness index,Brillouin index and McIntosh index （Dmc）,suggested a robust microbial functional diversity existed in the rhizospheric soil of the flue-cured tobaccos with the treatment. Among the soil enzymes,the polyphenol oxidase,urease and dehydrogenase all showed significantly higher activities＆nbsp;than those of CK by 52.4%,482.2%,16.3%,203.3% and 166.3%,respectively.The activities of polyphenol oxidase and dehydrogenase all reached an extremely significant difference level.It was,therefore,concluded that the addition of the microbial agent could ameliorate the micro-ecological system and the rhizospheric nutrient equilibrium of the soil promote the growth,yield and quality of the tobaccos.