不同引发处理对紫花苜蓿种子在盐逆境下发芽及幼苗生理生化变化的影响

EFFECTS OF DIFFERENT PRIMING TREATMENT ON GERMINATION OF ALFALF AND PHYSIOLOGICAL AND BIOCHEMICAL CHANGES OF ALFALFA SEEDLINGS UNDER SALT STRESS

以紫花苜蓿 (MedicagosativaL .)品种“维多利亚”和“金皇后”为材料 ,研究了H2 O、2 0 %PEG6 0 0 0u、2 %KNO3和 2 %KNO3 KH2 PO3引发处理对紫花苜蓿种子在高盐胁迫 (0 .8%NaCl)逆境下发芽及幼苗素质的影响 ,分别测定了发芽率、发芽势、发芽指数、淀粉酶、过氧化氢酶 (CAT)、过氧化物酶 (POD)、根系脱氢酶活性等指标。结果表明 ,四种引发处理均能显著提高“维多利亚”、“金皇后”紫花苜蓿品种种子发芽指数 ,促进盐逆境下种子萌发和幼苗生长。四种引发处理中 ,2 %KNO3 KH2 PO3效果最好 ,种子引发后显著提高了两个品种紫花苜蓿种子的发芽指数、发芽势、发芽率和幼苗干重 ,显著提高了CAT、α 淀粉酶活性和根系活力。

The seeds of two alfalfa (Medicago sativa L.) varieties, Victoria and Golden empress, were used to investigate the effects of four priming treatment on improving germination and growth under high-level salt stress (0.8% NaCl) condition. After alfalfa seeds were subjected to different priming with H 2O (hydropriming), 20% PEG, 2% KNO 3 and 2% KNO 3-KH 2PO 3 solution respectively, germination percentage, germination energy, germination index, root vigor and activity of several enzymes were measured in the salt stress. The results showed that germination index of alfalfa seeds primed by four priming treatment was significantly higher than that of the non-treated seeds, all priming treatment improved the seed germination and seedling growth under the salt stress condition. Among the four priming treatment, 2% KNO 3-KH 2PO 3 solution priming had the best effects on alfalfa seeds, which significantly increased germination percentage, germination energy, germination index, the dry weight of seedlings and enhanced activities of catalase (CAT), polyphenoloxidase (POD) and root dehydrogenase.