Investigation On Effects Of Methyl Jasmonate On The Nodulation And Nitrogen Fixation Of Soybean (Glycine Max (L.) Merr.)

Investigation on the effects of methyl jasmonate (MJ) on nodulation and nitrogen fixatino of 9 varieties of soybeans (Glycine max (L.) Merr.), including the effects of the methods of treatment and the concentration of MJ. The evidences can demonstrate the pathway and extent through which MJ exerted the influence on the nodulation and nitrogen fixation of soybean by experiments performed under the field and the soil sterilized.1. The effects of MJ on the basic characteristics of the nodulation and nitrogen fixation of soybeanThe point of the noduation initialized was at the 7th day after germination of the seed within the 22?2℃. So, the optimum for the treatment of MJ was the 7th day after germination. The promotion of MJ on the nodulation and nitrogen fixation of Caidou 5, 88-48, Dayiheidou was most significant on the 30th day after germination. MJ improved the nodule number and nodule weight on the 30th day after germination. The nitrogen content of the plant was on the decrease during the growth of the soybean seedlings. However, the activity of nodule nitrogenase varied according the varieties of the soybean.2. The effects of MJ on the nodulation and nitrogen fixation of soybean growing in the field10mol/L MJ was able to improve the nodule number and nodule weight of Dayiheidou growing in the field with little influence from the temperature.10mol/L MJ can stimulate the activity of nodule nitrogenase of Dayiheidou steadily. MJ exerted little effect on the nitrogen content of Dayiheidou at 30d after seed germination.Even though under the different condition, 10mol/L MJ still increased the fresh weight, dry weight and activity of nodule nitrogenase of various soybean seedings stably. The temperature had different effects on the nodulation of different varieties of soybean. And MJ reduced the nitrogen content of the soybeanseedlings slightly under different temperatures.3. The effects of MJ on the nodulation and nitrogen fixation of soybean (Dayiheidou) growing in the soil sterilizedIt could improve the nodule number and nodule weight of every plant more significantly with inoculation of high concentration (108L-1) of Rhizobium directly treated by MJ than the control (108L-1). Morever, the activity of nodule nitrogenase of Dayiheidou was increased more significantly than the control, which was inoculated Rhizobium directly treated by MJ. Even though the inoculation with Rhizobium could increase the nodulation of Dayiheidou, the nitrogen content of the soybean seedlings dropped slightly.