Study On The Effect Of Trichoderma Seed Dressing On The Growth Promotion And Phosphorus Absorption Of Mung Bean

The sandy soil in the western region of Heilongjiang Province provides a good growth environment for mung bean,but the content of nitrogen and potassium in the soil is high.The phosphorus is relatively scarce,which restricts the development of mung bean industry.Studies have shown that Trichoderma can activate phosphorus immobilized in soil,which can effectively solve this problem.At the same time,Trichoderma is an effective growth-promoting bacteria in the field of biological control.At present,it is mainly used in rice,maize and other crops.There is little research on the application of mung bean.A pot experiment was conducted to investigate the effects of Trichoderma seed dressing on agronomic traits,dry matter accumulation,leaf enzyme activity,soil enzyme activity,yield,phosphorus absorption and utilization of mung bean at flowering,podding and mature stages.The results showed as follows:1.Pot experiments showed that the root length,fresh and dry weight of mung bean could be increased effectively when the ratio of bacterial fertilizer to seed weight was 0.5%at flowering stage.At podding stage and mature stage,the growth-promoting effect of mung bean was obvious when the ratio of bacterial fertilizer and seed weight was 2%?3%.The plant height increased gradually with the increase of the ratio of bacterial fertilizer and seed weight.The highest yield was achieved by Trichoderma treatment with strain ratio of 2%,reaching 1024.71kg·hm^-2.Except the strain ratio of 1%,the yield of other Trichoderma treatments was significantly higher than that of the control group,and the yield increase rate was 6.29%?27.92%.2.Dry matter accumulation at maturity stage was significantly positively correlated with plant height,root length,chlorophyll content,root-shoot ratio,aboveground water content(R values were 0.812,0.884,0.772,0.703,0.822,respectively),and significantly negatively correlated with underground water content(R value was-0.809).3.The treatment with 0.5%strain ratio at flowering stage significantly improved the nitrate reductase activity.At podding stage and maturity stage,Trichoderma treatment significantly increased the nitrate reductase activity of mung bean leaves(except Trichoderma treatment with0.5%strain ratio at podding stage).Each Trichoderma treatment can improve the glutamine synthetase activity and glutamate synthetase activity of mung bean leaves at three periods.4.Soil enzyme activity was treated by Trichoderma with very low or very high proportion of bacterial manure and seed weight.The treatment of 2%strain ratio significantly increased urease activity at three periods.The soil phosphatase activity of the treatment with 0.5%?1%strain ratio was significantly higher than that of the control group at flowering and podding stages,and the treatment with 3%strain ratio showed advantages in the later growth stage.The treatment of0.5%and 2%strain ratio could improve soil invertase activity at three periods.The treatment with 1%and 3%bacteria could activate soil dehydrogenase activity at podding and mature stages.The treatment of 0.5%strain ratio had a great promoting effect on catalase activity at three periods.The treatment with 3%strain ratio could improve the protease activity at three periods.5.Trichoderma has great influence on the total phosphorus uptake and distribution of mung bean.Overall,the total phosphorus content of mung bean showed a decreasing trend.Total phosphorus uptake was 0.05?0.07 mg·plant^-1,with an average of 0.06 mg·plant^-1.The treatment with strain ratio of 3%had the highest phosphorus uptake of 21.85·10^-4kg per 100 kg grain.The treatment with strain ratio of 2%had the highest partial productivity of phosphate fertilizer.The total phosphorus absorption of mung bean per plant treated by Trichoderma was higher than that of the control group,with an increase of 9.40%?32.25%.Except for the treatment with 3%strain ratio,the phosphorus harvest index of other Trichoderma treatments was higher than that of the control group,and the highest phosphorus harvest index was 38.56%.6.The correlation analysis between phosphorus absorption and enzyme activity index of mung bean showed that there was a significant or very significant positive correlation between them.According to the results of multiple linear regression analysis,the linear regression equation between the total phosphorus uptake and the enzyme activity indexes was Y=-0.036+0.007X₂+0.077X₃+0.001X₄+0.007X₁.Path analysis results showed that the activities of soil dehydrogenase,catalase,protease and sucrase had a direct positive effect on the phosphorus uptake of mung bean.