A Study Of Zinc Finger Protein Gene OsLSD1.1 On Rice Root Environment

For plants,oxygen(O2)can be transported from shoot to root and diffused into rhizosphere soil by aerenchyma under flooding conditions,the abundant of O2 in the rhizosphere is believed to influence the rhizosphere environment,plant development and nutrient absorption.Therefore,it is of great significance to study the development of root aerenchyma,besides,the relationship between aerenchyma development and nitrogen uptaken in rice has been preliminarily explored in previous studies of our laboratory.In combination with previous studies,this study will explore the gene OsLSD1.1 mutation on the development of field aerenchyma,rhizosphere microbial activity and soil physical and chemical properties,so as to elucidate the possible mechanism of aerenchyma affecting the soil rhizosphere.In addition,ethylene acs2 and acs5 mutants were introduced to clarify the relationship between OsLSD1.1 and ethylene in the regulation of ventilator development pathway.In summary,the main findings are as follows:1.Under field growth condition,the root aerenchyma formation of mutants were inhibited and the cavities formed by different subsections were significantly underdeveloped compared to those of wild-type.The aerenchyma of ethylene acs2 and acs5 mutants under root box system and hydroponics condition were both significantly developed compared with the wild-type.According to the contrary development of root aerenchyma about OsLSD1.1 and ethylene mutants,it was concluded that OsLSD1.1 gene was involved in the regulation of the aerenchyna formation that wasn’t regulated by ethylene content of the waterlogged soil in Nanjing baguazhou.2.High throughput sequencing of the rhizosphere about OsLSD1.l mutants in hainan province showed that the community richness and diversity were significantly decreased,and abundance of nitrospira and nitrobacteria related to the ammoxidation process were also decreased dramatically.Accordingly,ammonia-oxidizing microorganism,soil physical and chemical properties were tested on the mutant in Hainan and Nanjing province.The results showed that the abundance of AOA and AOB in rhizosphere had a sharp drop and ammonium in soil increased remarkably when knocked out OsLSD1.1,but the change of nitrate was not significant.It was concluded that the removal of OsLSD1.1 resulted in oxygen depletion,and the change in oxygen secretion would cause a dramatic decline of ammoxidation-related microorganisms.Therefore,an obstructed process of soil ammoxidation and accompanying influence of soil C-N cycle,eventually lead to the decrease in nitrogen accumulation overground.