人工接种堆肥和自然堆肥微生物区系与分子多态性的变化

采用传统培养方法和PCR-DGGE技术研究了人工接种堆肥和自然堆肥微生物群落的演变过程。结果表明:(1)传统培养方法显示,两种堆肥堆制过程中微生物数量均呈“升高—降低—升高—降低”变化趋势,整个堆肥过程中细菌数量占优势。(2)DGGE图谱显示,两种堆肥不同时期存在不同的细菌种群,其条带数量亦呈“升高—降低—升高—降低”变化趋势。堆肥升温期条带丰富但优势条带不明显;堆肥高温期条带数量减少但出现优势条带,表明高温阶段以嗜热菌或耐高温菌为主;堆肥降温期条带数量再次增多;堆肥腐熟期条带数量少且无优势条带,表明腐熟阶段微生物种群数量少且代谢强度趋于平缓。(3)DGGE图谱表明,人工接种菌株成为堆肥高温期优势菌株。人工接种增加了堆肥中微生物总量,提高了堆肥微生物种群多样性,并且促进了堆肥菌群演替,从而缩短堆肥腐熟时间。

Variation of Microflora and Molecular Polymorphism in Inoculated and Natural Composts

Variation of microbial communities in inoculated and natural composts was studied with the traditional incubation method and the PCR-DGGE technology.Results indicate that 1)with the traditional incubation method,the population of microbes showed a wave-like curve,i.e.up-down-updown,in both composts and bacteria dominated the microbes in population,while 2)with the PCR-DGGE technology,the population showed a similar curve,though different microbial populations dominated at different composting stages.The DGGE graph showed abundance of bands and none in predominance during the warming up phase;the number of bands decreased but predominant bands appeared during the high temperature phase,suggesting that thermophiles were dominating microbes during this phase;the number of bands increased again during the cooling phase;and the number of bands dropped and no one remained in dominancy during the maturation phase,suggesting that the microbes were getting less in populations and their metabolism was levelling off during this phase.(3)The DGGE spectrum also showed that inoculated strains assumed predominance during the high temperature phase,and inoculation increased the total count of microbes,enriched microbial diversity and accelerated succession of microbes during composting,thus shortening duration of the composting process.