厌氧土壤灭菌不同添加物对日光温室土壤性质及微生物群落的影响

厌氧土壤灭菌(ASD)作为替代化学农药熏蒸灭菌技术在各地逐渐推广,但不同土壤类型、不同添加物厌氧土壤灭菌效果具有较大差异,田间条件下明确当地不同添加物厌氧灭菌对土壤性质及微生物群落效应,为日光温室绿色环保的土壤灭菌方法提供科学依据。结果表明:(1)除添加碳酸氢铵(AB)处理外,其他处理均可以显著降低0—20 cm土层电导率(EC),但仅灌水不添加物料(CK)处理20—40 cm土层NO_3~--N和EC显著增加,且AB处理显著增加0—20 cm土层NH_4~+-N及20—40 cm土层NO_3~--N;添加鸡粪(CM)处理0—20 cm土层NH_4~+-N极显著增加,NO_3~--N极显著降低,EC显著降低,土壤有机质、全氮和有效养分亦显著增加。(2)添加鸡粪(CM)显著降低细菌丰富度和均匀度,但土壤中植物促生菌(PGPR)芽孢杆菌属(Bacillus)及假单胞菌属(Pseudomonas)的相对丰度极显著增加。对真菌群落,不同处理真菌丰富度和均匀度与处理前差异均不显著,但添加碳酸氢铵(AB)、木醋液(PS)和鸡粪(CM)处理病原菌-镰刀菌属(Fusarium)的相对丰度均显著降低;同时,鸡粪(CM)处理有益属曲霉属(Aspergillus)丰度显著增加。(3)综合土壤理化性质、细菌和真菌群落变化,鸡粪作为有机碳源添加厌氧土壤灭菌效果较好,既可以厌氧灭菌同时也腐熟鸡粪,且各地原料来源方便,可同时实现化肥农药双减。

Effects of Different Amendments for Anaerobic Soil Disinfestation on Soil Properties and Microbial Community in Solar Greenhouse

Anaerobic soil disinfestation (ASD) as an alternative chemical fumigation of soil, has been gradually popularized in various places. However, effects of ASD is dependent on types of soil and amendments added. A field experiment was conducted to study the effects of ASD with different amendments on soil properties and microbial community, which would provide a scientific basis for environmentally friendly soil disinfestation method in solar greenhouse. The results showed that (1) the treatments except for ammonium bicarbonate treatment (AB) significantly decreased soil EC in 0-20 cm soil layer, but only irrigation without amendments (CK treatment) significantly increased soil EC, NO₃^--N in 20-40 cm soil layer. AB treatment significantly increased NH₄⁺-N in 0-20 cm soil layer and NO₃^--N in 20-40 cm soil layer. And the addition of chicken manure (CM treatment) significantly increased the NH₄⁺-N, pH, organic matter, total nitrogen and available nutrients, and significantly decreased the accumulation of NO₃^--N and EC in 0-20 cm soil layer. (2) CM treatment significantly decreased soil bacterial richness and evenness. However, the relative abundance of plant growth-promoting bacteria (PGPR), Bacillus and Pseudomonas increased significantly. For the fungal community, the diversity and abundance of fungi in different treatments were not significantly different from those of before treating. However, the relative abundance of pathogen-Fusarium in AB, PS and CM treatment decreased significantly. The relative abundance of deneficial Aspergillus of CM treatment significantly increased. (3) Considering soil physical, chemical and microbial properties, chicken manure as an organic carbon source, had more positively effects of disinfestation, not only increased its decomposition, but also easy to get. Meanwhile, the application of chicken manure would be helpful for implementing double reduction of fertilizer and pesticides.