Preparation Of Microbial Seed Coating Agent And Its Effect On Wheat Seedling Growth Under Salt Stress

Soil salinization is one of the important sources which affecting plant growth and reducing crop yield.Its impact on wheat is mainly reflected in reducing seed germination rate and hindering seedling growth.Plant growth-promoting rhizobacteria(PGPR)can promote the growth of crops under salt stress.Coating the seed by using PGPR is an effective way to improve soil environment,enhance plant stress resistance and increase crop yield.The common application methods of PGPR include granular bacterial fertilizer,biological seed coating agent and direct bacterial liquid irrigation.Among them,the way of adding seed coating agent has the advantages of convenience and economy,which is one of the important research directions.In this study,the salt tolerant PGPR from desert was applied with molasses,potassium silicate,CMC-Na and other auxiliary components to soak wheat seeds,and then straw powder,phosphate rock powder and potassium rock powder were wrapped on the outside,so as to complete the coating of wheat seeds.The formula of seed coating agent was preliminarily explored through single factor germination experiment and tissue culture bottle seedling experiment under salt stress;the promoting effect of seed coating agent on wheat seedlings growth was studied by taking seeds without seed coating agent as blank control and combining with wheat pot experiment under salt stress.The main results and conclusions are as follows:1.The amount and concentration of each component in the microbial seed coating agent were preliminarily determined.The combination of 1-6(FN0704 + FYP1101)and1-7(FN0105 + FN0704 + FYP1101)was selected from the combination of three strains of PGPR Bacillus FN0105,Arthrobacter FN0704 and Enterobacter FYP1101 to promote the growth of wheat Seedlings under salt stress.2.Effects of 1-6 and 1-7 seed coating agents on growth of potted wheat seedlings under salt stress: 1-6 seed coating agent significantly increased plant height,aboveground dry weight,underground dry weight and root activity of wheat seedlings;1-7 seed coating agent significantly increased plant height,root length,aboveground dry weight,underground dry weight,root activity and chlorophyll content of wheat seedlings.3.Effects of microbial seed coating agents on soil physical and chemical properties:1-6 and 1-7 seed coating agents significantly increased the content of organic matter in rhizosphere soil.The results showed that 1-6 type seed coating agent significantly increased the content of soil available nitrogen,while 1-7 type seed coating agent decreased the content of soil available nitrogen.In conclusion,the microbial seed coating agent developed in this study can significantly promote the growth of wheat seedlings under salt stress,which provides theoretical and practical basis for improving the production performance of plants under salt stress,improving saline alkali soil and protecting ecological environment.