摘要
设施辣椒栽培土传病害严重,已成为制约辣椒生产可持续发展的瓶颈问题。采用室内模拟的方法,以江苏铜山、南京、宜兴3地不同pH土壤为研究对象,研究原始沼液及铵强化沼液对辣椒疫霉菌的抑制效果,以期为探索新的克服土传病害方法提供理论依据。结果表明,淹水或沼液处理均导致土壤铵态氮含量增加,硝态氮含量降低。沼液处理后,土壤水溶性有机碳、水溶性有机氮显著增加。淹水降低了土壤细菌、真菌的数量及土壤脲酶、脱氢酶活性,而对放线菌数量影响不明显。淹水期间,土壤细菌、放线菌数量呈先上升后下降趋势,而真菌数量持续下降。铵强化沼液处理的土壤细菌数量最多,真菌、放线菌数量处理间差异不明显。各处理脱氢酶、脲酶活性于第2～4 d内达最大值,此后缓慢下降。试验结束时,铜山、南京、宜兴3种土壤脱氢酶活性较试验初始值分别降低15.2%～59.6%、7.9%～38.4%、2.8%～37.9%,脲酶活性分别下降了16.7%、17.3%、17.1%;疫霉菌的数量分别下降2～3、1～2、1个数量级。铵强化沼液处理的疫霉菌数量最低,较淹水对照分别降低54.7%、62.8%、51.9%,说明提高沼液氨浓度,可以增强对土壤疫霉菌的抑制效果。
Soilborne diseases caused by various phytopathogens have been a bottleneck in intensive production of chilli peppers. We investi- gated the effects of anaerobically digested slurry（ADS, 472 mg L-1 NH4＋-N） and NH4＋-intensified ADS（ 1000 mg L-1 NH4＋-N） on the growth of Phytophthora capsici, the culprit of Phytophthora blight of chilli pepper, and physic-chemical and microbial properties in three different soils using water as control （CK）. Compared to the original soils, water flooding or ADS application resulted in higher ammonium levels but lower nitrate levels in the soils. Applying ADS also significantly increased concentrations of water soluble carbon and water soluble nitrogen in the soils in comparison with water control. Flooding with water or ADS decreased soil bacterial and fungal populations, but had no signifi- cant impact on actinomycetic population~ Of three treatments, the NH4＋-intensified ADS treatment had the highest number of soil bacterial community, while no significant differences were found in fungal and actinomycetic communities. Activities of soil dehydrogenase and urease reached peak on day 2 to 4 and decreased thereafter. Flooding treatments decreased the population of P. capsici in the soils by 10 to 1000 folds. The least number of P. capsici was observed in soil treated by NH4＋-intensified ADS. The pathogen population decreased greater in al- kali soil than in other soils. The results show that ADS with ammonium could enhance soil＇s capability and stability to suppress P. capsici.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2014年第3期539-546,共8页
Journal of Agro-Environment Science
基金
江苏省农业科技自主创新资金项目(CX(13)3035)
农业部公益性行业专项项目(201203050-1)
关键词
沼液
土壤处理
铵态氮
疫霉菌
anaerobically digested slurry
soil disinfection
ammonium
Phytophthora capsici
