不同老化程度的不结球白菜种子活力指标变化及其相关分析

以不结球白菜品种‘高梗白’种子为材料,采用高温(42℃)高湿(相对湿度100%)人工加速老化处理,研究不同老化程度下种子活力指标的变化及其相关性。结果显示:(1)发芽指标(除不正常苗率)和出苗指标均随种子老化程度的加深而显著下降,不正常苗率显著上升。(2)随老化程度的加深,种子中超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性显著下降;种子的超氧阴离子(O2.-)产生速率先增高后降低,过氧化氢(H2O2)含量逐渐增加,丙二醛(MDA)含量下降,种子浸出液相对电导率升高;种子的可溶性糖含量、可溶性蛋白含量和脱氢酶活性下降,α-淀粉酶活性先升高后降低。(3)老化种子的发芽势、发芽率、SOD活性、H2O2含量、相对电导率和可溶性糖含量与出苗指标间均存在极显著相关性。研究表明,不结球白菜种子的发芽势、发芽率、SOD活性、H2O2含量和可溶性糖含量随老化程度加深的变化规律一致,且指标间以及与出苗指标均有极显著相关性,可以作为检验不结球白菜种子活力的候选指标。

Vigor Indexes Change and Correlation of Non heading Chinese Cabbage Seeds in Different Aging Degrees

In this study,with non-heading Chinese cabbage(Brassica campestris ssp.chinensis Makino.) variety ’Gaogengbai’ as material,seed vigor indexes and correlation of different aging degrees were studied during artificial aging treatment at 42℃ and RH 100%.The results as followed:(1)The seed germination indexes(except abnormal seedling rate) and emergence indexes significantly decreased with the increase of aging degree and abnormal seedling increased significantly.(2)With the increase of aging degree,the activities of superoxide dismutase(SOD),peroxidase(POD) and catalase(CAT) decreased significantly;The speed of O-·2 production firstly went up and then slowed down.The hydrogen peroxide(H2O2) content kept increasing,the content of malondialdehyde(MDA) decreased and the relative electrolyte leakage increased;Soluble sugar content,soluble protein content and dehydrogenase activity kept decreasing and α-amylase activity firstly went up and then down.(3)The germination energy,germination rate,SOD activity,H2O2 content,the relative electric conductivity and soluble sugar content of aging seed had very significant correlation with emergence indexes.Comprehensive analysis showed that the changes of germination energy,germination rate,SOD activity,H2O2 content,the relative electric conductivity and soluble sugar content were consistent with aging degree deepen,and they showed very significant correlation with emergence indexes.Therefore,they can serve as candidate indicators for non-heading Chinese cabbage seed vigor test.