Effects of Melatonin Soaking on Seed Germination and Physiological Indexes of Cowpea Under Low Temperature Stress
Taking the seeds of the cowpea variety'Huagan Lyuxiu'as the test materials,under the conditions of 0,50,100 and 200 μmol·L-1 melatonin(MT)concentration,undergoing a low temperature environment of 10 ℃,the germination rate,antioxidant enzyme activity,superoxide anion(O2)production rate,content of osmotic adjustment substances,and MDA content of cowpea seeds were studied under the treatment of melatonin,in order to provide reference for the application of cowpea in facility production.The results showed that,1)germination of cowpea seeds was inhibited under low-temperature stress,whereas the application of exogenous melatonin improved seed germination under low-temperature stress,whereas the germination rate was still lower than that of the control.2)Both peroxidase(POD)and catalase(CAT)activities in cowpea seeds reached a maximum on 4th day of the 200 μmol·L-1MT treatment,superoxide dismutase(SOD)activity peaked on 6th day of the 200 μmol·L-1 MT treatment,whereas the MDA content peaked on 6th day of the 100 μmol·L-1MT treatment,and the rate of superoxide anion(O2)production reached a minimum on 6th day of the 50 μmol·L-1 MT treatment.3)The free proline content reached a maximum on 6th day of the 50 μmol·L-1MT treatment,the soluble protein content reached a maximum on 4th day of the 100 μmol·L-1MT treatment,and the soluble sugar content reached a maximum on 2nd day of the 200 μmol·L-1 MT treatment.It was found that the application of exogenous melatonin under low-temperature stress conditions could increase the germination rate of seeds,enhance the activity of antioxidant enzymes,reduce the content of MDA,slow down the production rate of superoxide anion(O2),and promote the accumulation of osmotic-regulating substances,which could effectively alleviate the damage caused by low-temperature stress to cowpea seeds during germination,enhance their tolerance to low temperatures,and restore their normal growth ability.The effect was better when a concentration of 200 μmol·L-1 was applied.
万方数据
维普
