Effect Of Uniconazole On Waterlogging Stress During The Reproductive Period Of Mungbean

Waterlogging stress is one of the main abiotic stresses during the growth and development of crops.It is of great significance for disaster prevention and reduction of mung bean cultivation to study how to relieve the damage of mung bean under waterlogging stress.Two mung bean varieties of Lufeng 2 and Lufeng 5 were used as the experimental material,explored the effects of the beginning bloom?R1 stage?and the beginning seed?R5 stage?waterlogging stress on mung beans.The effect of uniconazole?S3307?for different submergence resistance mungbean waterlogged damage relief mechanism on agronomic characters,accumulation of dry matter,photosynthetic parameters,antioxidant enzyme system,osmotic regulation substances and the influence of grain quality,yield and yield components at 2017-2018,the main results are as follows:1.The normal growth of mungbean was inhibited under different periods of waterlogging stress,and the plant height,stem diameter and dry matter quality of mungbean were reduced.The plant height of mungbean under waterlogging stress was reduced and the stem diameter and dry matter quality of mungbean were increased after spraying S3307.The total dry matter mass of Lufeng 2 and Lufeng 5 increased by 13.78% and 18.27% compared with waterlogging treatment at R1 stage respectively,and increased by 10.59% and 16.14% respectively at R5 stage.Chlorophyll content?SPAD?,net photosynthetic rate?P_n?,transpiration rate?T_r?,stomatal conductance?G_s?,and intercellular CO₂ concentration?C_i? of mungbean leaves decreased under waterlogging stress at R1 and R5 stages.In addition,the reduction rate under the waterlogging stress at R1 stage was higher than R5 stage.SPAD,net photosynthetic rate,transpiration rate and stomatal conductance of the leaves of mungbean under waterlogging stress were significantly increased after spraying S3307 on the leaf surface.2.The normal physiological metabolism of antioxidant enzymes and reactive oxygen species was affected by waterlogging stress.The malondialdehyde?MDA?contents and superoxide radical?O₂^-·?production rate of mungbeans were significantly increased after waterlogging stress.Superoxide dismutase?SOD?activities,peroxidase?POD?activities,ascorbate peroxidase?APX?activities,glutathione resuctase?GR?activities,ascorbic acid?AsA? contents and glutathione?GSH?contents were changed differently in different varieties and under different waterlogging periods.The protective enzyme activity and non-enzymatic antioxidant content of the waterlogged mungbean were enhanced,the membrane peroxidation of the leaves of mungbean was alleviated under stress,and the physiological damage of the waterlogged mungbean was alleviated by spraying S3307 to improve the SOD activities,POD activities,APX activities,GR activities,As A contents and GSH contents,and decreased the MDA contents and O₂^-· production rate.3.The yield per plant of mungbean under waterlogging stress were decreased at R1 and R5 stages.The yield per plant of mungbean were increased at R1 and R5 stages after spaying S3307,while the alleviating effects of yield component were different in two stages.The pods per plant and seeds per pod of mung bean were significantly increased after S3307 was sprayed under waterlogging stress at R1 stage.The seeds per pod of mung bean was significantly increased after spraying S3307 under waterlogging stress at R5 stage,and then the yield per plant of mung bean was increased.The yield reduction rate of two kinds of mung beans was 24.70%³3.63%,and the remission rate of mung bean was 28.91%⁵2.34% at R1 stage;the yield reduction rate was 18.07%²8.87% at R5 stage,and the remission rate was 13.77%²7.36% at R5 stage.Above all,S3307 had different regulatory effects on different mung bean varieties at different waterlogged stages.The application of S3307 can effectively enhance the mung bean submergence resistance under waterlogging stress through alleviating the waterlogging stress effects on the growth of mung bean,improving the waterlogged mung bean leaf physiological function and photosynthetic abilities,enhancing the waterlogged mung bean protective enzyme activities,increasing the contents of antioxidant enzyme and osmotic regulation substances contents,reducing waterlogging stress influence on quality of mung bean grain,thus reduce the yield reduction.