豆科植物土壤浸提液对马铃薯连作土壤微生物群落和酶活性的影响

发布时间：2018-05-19 11:32

本文选题：马铃薯连作土壤 + 豆科植物(清水苜蓿)　；参考：《甘肃农业大学》2016年硕士论文

【摘要】：为探明轮作豆科植物对马铃薯连作土壤微生物群落和酶活性变化规律的影响。本试验以马铃薯品种‘新大坪’为供试品种,把提取的马铃薯连作田土壤浸提液和豆科植物(清水苜蓿)土壤浸提液配成1:1、1:2、1:3、1:4和1:5 5种比例来浇灌基质栽培的马铃薯植株,研究4年龄豆科植物土壤浸提液对马铃薯第4年连作田土壤微生物群落、酶活性和理化性质的影响。选择适宜的马铃薯-豆科轮作模式,为克服马铃薯的连作障碍提供技术支撑和理论依据。本试验获得如下主要结论:1.在马铃薯的生育期内基质电导率和p H呈先升高后下降的趋势。其中1:4的土壤浸提液处理可以显著提高基质的阳离子交换量和有机质含量,同时可以降低基质的电导率和p H;1:3的土壤浸提液处理显著提高了基质的速效氮含量;1:2的土壤浸提液处理提高了基质的速效磷和速效钾含量。2.豆科植物土壤浸提液对基质中酶活性的变化影响显著,其中1:4的土壤浸提液处理提高了马铃薯基质的过氧化氢酶和碱性磷酸酶活性,对马铃薯块茎形成初期和块茎成熟期的蔗糖酶和脲酶活性有一定的促进作用;1:3处理显著提高了马铃薯块茎增长期的脲酶和蔗糖酶活性。3.豆科植物土壤浸提液对马铃薯基质中微生物数量的变化影响显著,其中1:4的土壤浸提液处理提高了马铃薯整个生育期的嫌气性自生固氮菌、硝化细菌、反硝化细菌数量,同时增加了马铃薯块茎形成初期的放线菌数量;1:3处理提高了马铃薯块茎增长期的细菌、放线菌和好气性自生固氮菌数量,同时降低了马铃薯整个生育期的真菌数量;1:5的土壤浸提液处理提高了马铃薯块茎形成初期的反硝化细菌数量。4.马铃薯栽培基质中微生物数量、酶活性和理化性质间存在一定的相关性。细菌与放线菌数量呈极显著正相关,而真菌数量与酶活性和理化性质相关性不显著,放线菌与过氧化氢酶、碱性磷酸酶、蔗糖酶、脲酶、速效氮、速效磷、速效钾和有机质呈极显著正相关;在氮素生理群中除好气性自生固氮菌与p H呈极显著正相关外,硝化细菌和反硝化细菌均与p H呈极显著负相关。过氧化氢酶、脲酶、蔗糖酶和碱性磷酸酶与理化性质和养分相关性显著。过氧化氢酶、脲酶、蔗糖酶和碱性磷酸酶相互之间均存在极显著正相关关系。
[Abstract]:In order to investigate the effect of rotation legumes on soil microbial community and enzyme activity of potato continuous cropping. In this experiment, the potato variety 'Xindaping' was used as the tested variety. The extracted soil extract of potato continuous cropping field and the soil-extract solution of leguminous plants (Medicago sativa) were mixed into 1: 1 / 1: 1: 2: 1: 1: 1 / 4 and 1:5 to irrigate potato plants cultivated in substrate. The effects of soil extracts from leguminous plants of 4 ages on soil microbial community, enzyme activity and physical and chemical properties in potato field for the fourth year were studied. The suitable potato-legume rotation model was selected to provide technical support and theoretical basis for overcoming the obstacle of potato continuous cropping. The main conclusions of this experiment are as follows: 1. During the growth period of potato, the electrical conductivity and pH of substrate increased first and then decreased. The treatment of 1:4 soil extract significantly increased the cation exchange capacity and organic matter content of the substrate. At the same time, the electrical conductivity of the substrate and the soil extractant treatment of pH1: 3 significantly increased the available nitrogen content of the substrate and the soil extractant of 1: 2 increased the available phosphorus and potassium contents of the substrate. The soil extract of leguminous plants had a significant effect on the activity of enzyme in the substrate. The enzyme activity of catalase and alkaline phosphatase in potato substrate was increased by the treatment of 1:4 soil extract. It can promote the activities of sucrase and urease in the initial stage of tuber formation and tuber maturation. The treatment of 1: 3 significantly increased the urease and sucrase activity of potato tuber. The soil extract of leguminous plants had a significant effect on the change of microbial quantity in potato substrate, and the soil extract treatment at 1:4 increased the number of anaerobic nitrogen-fixing bacteria, nitrifying bacteria and denitrifying bacteria during the whole growth period of potato, and the amount of nitrogen-fixing bacteria, nitrifying bacteria and denitrifying bacteria were increased during the whole growth period of potato. At the same time, the number of actinomycetes in the initial stage of potato tuber formation was increased by 1: 3 treatment, and the number of bacteria, actinomycetes and aerobic autogenous nitrogen-fixing bacteria in potato tuber growth stage was increased. The number of denitrifying bacteria in potato tubers at the initial stage of tuber formation was increased by the treatment of 1: 5 soil extract at the same time. There was a certain correlation between the number of microorganisms, enzyme activity and physicochemical properties in potato substrate. The number of bacteria and actinomycetes was significantly positive correlation, but the number of fungi was not correlated with enzyme activity and physical and chemical properties, actinomycetes and catalase, alkaline phosphatase, sucrase, urease, available nitrogen, available phosphorus. There was a very significant positive correlation between available potassium and organic matter, and a very significant negative correlation between nitrifying bacteria and denitrifying bacteria except aerobic autogenous nitrogen fixing bacteria and pH in nitrogen physiological group. Catalase, urease, sucrase and alkaline phosphatase were significantly correlated with physical and chemical properties and nutrients. The correlation between catalase, urease, sucrase and alkaline phosphatase was very significant.
【学位授予单位】：甘肃农业大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：S532;S154

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