【作者】 李妮；

【导师】 宋付朋；

【作者基本信息】 山东农业大学 ， 土壤学， 2013， 硕士

【摘要】 我国是大蒜种植面积最大和产量最多的国家之一。在传统种植区,大蒜种植虽然在初期取得了一定成效,但随着种植时间的延续,各种问题接踵而至,如长势变弱、产量降低和品质下降,严重的出现各种病虫害,如根腐病、白腐病、叶枯病等。针对该问题,本文从土壤微生物数量、土壤酶活性、土壤微生物遗传多样性及功能多样性4个方面对不同种植年限的大蒜近根区土壤进行研究,旨在从土壤微生物学水平分析随着种植年限的延长大蒜近根区土壤微生物学特性的变化特点及其土壤理化性状变异的原因,以期为大蒜生产提供科学技术依据与支撑。主要研究结果如下：(1)随着种植年限的增加,大蒜近根区土壤细菌数量变化与微生物总量变化均为种植15年最少、2年最多；真菌和放线菌数量变化一致,表现为种植15年最少、30年最多。(2)随着种植年限的增加,土壤脲酶、过氧化氢酶、蔗糖酶和磷酸酶的活性显著提高,除脲酶活性种植8年最低、20年最高,其余均为种植2年最低、20年最高。(3)种植年限越长大蒜近根区土壤细菌群落结构变化越大,其相似性由87%下降至77%。(4)种植8年和30年分别为大蒜近根区土壤微生物群落整体活性的最高点和最低点；各种植年限大蒜近根区土壤微生物群落在氨基酸类、胺类和碳水化合物类的利用方面差异显著；种植年限越长其土壤微生物群落均匀度越低。(5)大蒜近根区土壤细菌数量和微生物总量与土壤全氮和速效钾含量呈显著或极显著负相关关系；蔗糖酶活性与土壤EC和全氮含量、磷酸酶活性与土壤全氮含量呈显著正相关关系；Shannon旨数与土壤含水量、Simpson指数与土壤有效磷含量均呈显著的负相关关系。更多还原

【Abstract】 China is one of the largest countries of planting area and yield of garlic. In traditional growing areas, although garlic growth achieved certain achievements in the early time, problems ensued with the planting years lasting, for example, growing weak, yield and quality deline, even all kinds of disease and insect pests, such as root rot disease, white rot disease, leaf blight disease, as so on. Aiming at the problem, garlic rhizosphere soils of different planting years were studied in four aspects, obtaining soil microbial population, soil enzyme activity, soil microbial genetic and functional diversity. Then change and rerelation to physical and chemical properties of garlic rhizosphere soil microbial characteristics with continuous planting years could be analyzed from the level of soil microbial. Main results were as follows:1. With the increase of planting years, change of garlic rhizosphere soil bacteria was the same to total microbial in population. They were the least in15planting years, and the most in2planting years. Change of fungi and actinomycetes in population was coincident, showing least in15planting years and most in30planting years.2. With the increase of planting years, urease activity, catalase activity, sucrase activity and phosphatase activity of garlic rhizosphere soil improved significantly. Except urease activity was the lowest in8planting years and the highest in20planting years, the rest three enzymes were all the lowest in2planting years and the highest in20planting years.3. The longer planting years were, the greater change of garlic rhizosphere soil bacteria community structure was. Their similarity declined from87%to77%.4. The whole activity of garlic rhizosphere soil microbial community was the highest in8planting years and the lowest in30planting years. Garlic rhizosphere soil microbial community of each planting years had significant difference in the use of amino acids, amines and carbohydrates. The longer planting years were, the lower of McIntosh evenness of garlic rhizosphere soil microbial community was.5. Both bacteria and total microbial in population of garlic rhizosphere soil had a (highly) significant negative relationship with TN and AvK; Sucrose activity with EC and TN, phosphatase activity with TN all had a significant positive relationship; Shannon index with water content, Simpson index with AvP had a significant negative relationship.更多还原