Effect Of Nodule Growth-promoting Agent On Nodule Growth And Nitrogen Fixation In Soybean

Jindou 25 was used to investigate on the effects of Nodule growth-promoting agent on nodulation and nitrogen fixation of the varieties. There was a successful fertilizer developed in Shanxi University. It could make significant increase in the availability of early nodules of legume crops. The effect of organic fertilizer nodule growth-promoting agent to the symbiotic nitrogen fixation in several different concentrations of soybean nodulation was investigated in this assay.Hydroponic experiment, respectively, the regional pot experiment and field test of sampling were used to research the effect of nodule growth-promoting agents on rhizobia (Sinorhzobium fredii) growth, soybean plant growth and nodulation and nitrogen-fixing efficiency, and then explore the growth- promoting agent's function to rhizobia, the host legume crops and the efficiency of nitrogen fixation.1. Effect of nodule growth-promoting agent on the growth of Sinorhzobium fredii.The rotational speed was 220 rpm, and then cultured on the shaking table at 28-30℃for about 45 h. Sinorhzobium fredii was cultured in constant temperature water box at 220 rpm,28-30℃。Growth curve was achieved by the absorption value UV 600 nm determined per 3 h in 45 h. The results showed that the appropriate application amount of nitrogen could increase the speed of rhizobia growth, and the higher concentration of nodule growth-promoting agent could play a inhibition effect role on the speed of rhizobia growth.2. The effect of nodule growth-promoting agent on nodulation and nitrogen fixation in soybean.The solution culture experiment and the pot experiment were carried out to study the effect of nodule growth-promoting agent on nodulation and nitrogen fixation.In different growth periods of soybean, different concentrations of nodule growth-promoting agent were added in the flowerpots. Detected the plant dry weight, the number of root nodule, the root activity, the nitrogenase activity and the leghaemoglobin contents of each experimental group to study the effect of nodule growth- promoting agent. The results showed that the physiological indexes of the group added nodule growth-promoting agent and rhizobium were not higher than the group added nodule growth-promoting agent in singles at seedling stage. But at initial bloom stage, the reciprocity of rhizobium and plant becomes more and more important acted by nodule growth-promoting agent. The physiological indexes of the group added nodule growth-promoting agent and rhizobium were higher than the group added nodule growth-promoting agent at initial bloom stage remarkablely.3. The effect of nodule growth-promoting agent on nodulation and nitrogen fixation in soybean in field. The results showed that the physiological indexes of the group including nitrogenase activity, leghaemoglobin contents and number of root nodule which were added nodule growth-promoting agent in singles were higher than the group added nitrogenous fertilizer in sing...