Abstract: The effect of controlling deterioration (0,24,48,72,96,120 h) on the antioxidant enzyme activities and lipid peroxidation of Leymus chinensis seed with different moisture contents (4%,10%,16%,22%,28%,34%,40%) was studied to explore seed deterioration under different moisture contents. Results showed that the rate of seed germination and superoxide dismutase (SOD) activity obviously decreased at the same moisture level, the activities of catalase (CAT) and malondialdehyde (MDA) first declined then increased, peroxidase (POD) increased initially, then declined after extended deterioration time. Seed germination rate, SOD and POD activities decreased with seed moisture content increasing at the same deterioration time, whereas MDA initially increased then declined. During deterioration, both seed moisture content and deterioration time had a significant effect on seed germination rate, SOD, POD and MDA contents(P<0.01). The vigor of seed with high moisture content decreased significantly during long deterioration processing. Lower moisture content (4%) was more favorable for seed storage.

Key words: Leymus chinensis, Moisture content, Controlling deterioration, Seed

摘要： 试验以7种不同含水量(4%,10%,16%,22%,28%,34%,40%)羊草(Leymus chinensis)种子为材料,研究6种不同劣变时间(0,24,48,72,96,120 h)对羊草种子发芽率、抗氧化酶以及膜脂过氧化程度的影响,探索不同含水量羊草种子劣变的内在机制。结果表明:随着劣变处理时间的延长,羊草种子发芽率、超氧化物歧化酶(SOD)活性总体呈下降趋势,过氧化氢酶(CAT)活性与丙二醛(MDA)含量总体呈先下降后上升趋势,而过氧化物酶(POD)活性呈先上升后下降趋势。随着种子含水量的增高,劣变处理后羊草种子发芽率下降明显,死种子增多,SOD和POD酶活性整体呈下降趋势,MDA含量呈先上升后下降的变化趋势。在劣变过程中,种子含水量、劣变时间对种子发芽率、SOD和POD酶活性有极显著影响(P<0.01),水分与时间互作对POD酶活性以及MDA含量影响极显著(P<0.01)。高水分含量羊草种子在超长时间劣变处理后,种子活力下降明显;4%水分含量对于羊草种子的储藏较为有利。

关键词: 羊草, 含水量, 控制劣变, 种子