脱水速率对天冬种子发芽率和抗氧化酶活性的影响

Effects of Drying Rates on Germination Rate and Antioxidant Enzyme Activities of Asparagus cochinchinensis Seeds

以天冬种子为试材,采用自然阴干(25℃)、硅胶干燥(25℃)、烘箱干燥(60℃)3种方式将天冬种子干燥,研究了不同含水量种子的发芽率和超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性,以期为天冬种子的贮藏提供参考依据。结果表明:1)天冬种子初始含水量为37.3%,发芽势和发芽率分别为50.7%、89.3%,SOD、POD、CAT活性分别为140.6、92.1、125.6U·g^(-1)·min^(-1);2)天冬种子耐脱水,属于正常性种子,自然阴干22d,含水量降至15.9%,发芽势和发芽率未显著变化,SOD、POD、CAT活性先升高后稳定;3)硅胶脱水过程中,种子抗氧化酶活性增强,未造成脱水伤害,其中硅胶脱水72h,含水量降至9.9%,发芽势和发芽率未显著变化;4)烘箱干燥脱水速度过快,种子脱水耐性降低,发生脱水伤害,用60℃烘箱干燥6h后种子含水量降至9.9%,发芽势和发芽率分别降至28.7%和52.0%。

Taking Asparagus cochinchinensis seeds as test materials,the seeds were dried by natural ventilation(25℃),silica gel(25℃)and oven(60℃).The germination rate and activities of SOD,POD and CAT of seeds with different water content were studied,in order to provide reference for the storage of Asparagus cochinchinensis seeds.The results showed that,1)The initial water content of seeds was 37.3%,the germination potential and germination rate were 50.7%and 89.3%respectively,and the enzyme activities of SOD,POD and CAT were 140.6,92.1,125.6U·g^(-1)·min^(-1) respectively.2)The seeds were dehydrated resistant and belonged to normal seeds.After natural drying for 22days,the water content decreased to 15.9%.The germination potential and germination rate did not change significantly,and the activities of SOD,POD and CAT increased first and then stabilized.3)During the drying process of silica gel,the antioxidant enzyme activity of seeds increased without dehydration damage.After 72hours of drying treatment,the water content decreased to 9.9%,and the germination potential and germination rate did not change significantly.4)The dehydration speed of oven drying was too fast,the dehydration tolerance of seeds was reduced,and dehydration injury occurs.After drying in the oven at 60℃for 6hours,the water content was reduced to 9.9%,and the germination potential and germination rate were reduced to 28.7%and 52.0%respectively.