Microbial Characteristics Of Garlic Rhizosphere Soil Of Different Planting Years

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.