超干处理对沙芥属蔬菜种子活力及抗氧化代谢的影响

Effects of Ultra-Dry Treatment on Vigor and Antioxidative Metabolism of Pugionium Seeds

【目的】研究超干处理对沙芥属蔬菜种子活力及抗氧化代谢的影响,为沙芥属蔬菜种子耐干性及贮藏提供理论基础。【方法】采用硅胶干燥法将沙芥种子(4.5%)和斧形沙芥种子(4.3%)的含水量分别降至3.1%、2.2%、1.3%,测定不同含水量条件下种子的生活力及抗氧化代谢的变化。【结果】种子含水量由CK降至1.3%时,斧形沙芥种子活力保持较高水平,而沙芥种子则急剧下降;脱水后3个含水量的沙芥和斧形沙芥种子的相对电导率均低于CK,细胞膜完整性保持良好;超干处理会使沙芥属蔬菜种子的MDA含量和O2产生速率增加;超干处理对种子内4种抗氧化酶(SOD,CAT,GPX,APX)活性无明显影响。【结论】沙芥和斧形沙芥种子均具有较强的耐干性,但斧形沙芥种子抵御伤害的能力及种子的耐干性均强于沙芥种子,含水量2.2%是沙芥种子发芽率和活力的转折点。

[Objective] The effect of ultradry treatment on dynamic change of vigor, antioxidative metabolism of Pugionium. seeds were determined, which would provide a theoretical basis for desiccation tolerance and storage of the seeds. [Method] The moisture content ofP. cornutum（L.） Gaertn. and P. dolabratum Maxim. were reduced to 3.1%, 2.2%, 1.3% from 4.5% and 4.3% （CK）, respectively, with silica gel, and the vigor and antioxidative metabolism were detected when the seeds were re-moistened. [Result] The vigor of P. dolabratum Maxim. seeds maintained at a relatively higher level, while the P. cornutum（L.） Gaertn. seeds decreased sharply when the moisture content dropped to 1.3% from respective CK. Relative electrical conductivity of the two species seeds with ultradry treatment were lower than the CK and the integrity of cell membranes was conserved. Ultradry treatment accelerated the generation of superoxide generation rate （O~） and malondialdehyde （MDA）, but the treatment did not affect the activities of antioxidant enzymes of the two species seeds obviously such as SOD, CAT, GPX, APX. [ Conclusion] The results showed that both of the seeds of P. cornutum（L,） Gaertn. and P. dolabratum Maxim. had strong desiccation tolerance, however, the ability of resisting damage and the desiccation tolerance ofP. dolabratum Maxim. seeds were stronger than P. cornutum（L.） Gaertn. seeds, and the moisture content of 2.2% was the turning point of germination and vigor of P. cornutum （L.） Gaertn. seeds.