丛枝菌根真菌对还田麦秆分解及玉米生物量的影响

Effects of arbuscular mycorrhizal fungi colonization on wheat-straw decomposition and maize biomass

通过盆栽试验探索接种丛枝菌根真菌摩西管柄囊霉(Funneliformis mosseae)对麦秆分解速率、土壤微生物量、分解酶活性和玉米生物量的影响。结果表明,培养90d,F.mosseae能与玉米根系形成共生系统,定殖率超过63%,秸秆还田同时接种F.mosseae菌剂显著提高了玉米根系干物质质量。与单独秸秆还田(对照)相比,接种F.mosseae菌剂并进行秸秆还田处理显著促进了麦秆的分解。培养90d,接种F.mosseae菌剂并进行秸秆还田处理的土壤微生物量以及与碳、氮、磷元素矿化相关的土壤纤维素酶活性、土壤蛋白酶活性和土壤碱性磷酸酶活性均显著高于对照。说明,接种F.mosseae菌剂并进行秸秆还田处理可以通过提高土壤微生物量和分解酶的活性,直接或间接地影响小麦秸秆的矿化过程,正向调节农田土壤生态系统中有机质的养分循环。

The effects of arbuscular mycorrhizal(AM)fungi(Funneliformis mosseae)colonization on the decomposition rate of wheat straw,soil microbial biomass,soil enzyme activities and maize biomass were conducted in a pot experiment.Results showed that after 90 days incubation,F.mosseae could form symbiotic system with maize roots,and the colonization percentage was over 63%.Wheat straw returning to field and inoculating with F.mosseae significantly increased root biomass of maize.The inoculation of F.mosseae significantly promoted the decomposition rate of wheat straw.After 90 days of culture,soil microbial biomass and the enzyme activities involved in soil carbon,nitrogen and phosphorus mineralization(cellulase,protease and alkaline phosphatase)under F.mosseae colonization treatments were significantly higher than those in the control.These results reflected that wheat straw returning to the field and inoculating AM fungi could directly or indirectly participate in the mineralization of wheat straw by increasing soil microbial biomass and soil enzyme activities,which could positively regulate the release of organic matter in farmland soil ecosystem.