Relation Between The Soil Microbial Characteristic And Biological Availability Of Nitrogen For Tobacco, Nicotiana Tabacum L. K326

This research, taking flue-cured tobacco ( Nicotiana tabacum L. K326) as material, conducts experiments in fields and potted plants, and keeps on observing the dynamic changing process of tobacco soil, the micro-organism related to the nitrogen transformation, and the nitrogen nutrition of the tobacco root during the entire growth of the tobacco. It also explores the environmental factors influencing soil microorganism absorption and nitrogen transformation, and analyzes the relation of soil microorganism property and biological validity of nitrogen. Major result is as follows: 1 . The quantity and dynamic changes of tobacco soil rhizosphere main bacterium physiology group and its biochemistry intensityThe quantity of ammoniation bacterium and the ammoniation intensity are lower in the initial period; and gradually increase along with tobacco's unceasing growth; then realize the maximum in tobacco mature intermediate stage; and drop afterwards. The nitrifying bacteria quantity and the nitrification intensity reach the top in root-stretching period, and descend continuously after that. They fall to the lowest point in current bud period, and display the rising tendency afterwards. However, the denitrifying bacteria's change tendency and the nitrifying bacteria is completely the opposite. 2. The dynamic changes of tobacco soil biomass carbon and biomass nitrogenThe research shows that the soil biomass carbon remains dropping continually in entire period of tobacco growth. But the soil biomass nitrogen is comparatively low in the root-stretching period. It grows gradually with tobacco's exuberant growth, gets to the summit in current bud period, and plummets dramatically after that. The research...