外源海藻糖浸种对低温胁迫油菜种子萌发及幼苗生长的影响

为提高抗寒性,促进油菜种子发芽及幼苗生长,以甘蓝型油菜品种中油杂19为材料,研究外源海藻糖浸种对低温胁迫下油菜种子萌发及幼苗生长的影响,阐明外源海藻糖浸种的寒害缓解作用.结果表明,在低温处理下(10℃),油菜种子萌发受到抑制,发芽势、发芽率、发芽指数及活力指数均显著下降,平均发芽时间显著延长;种子萌发过程中异柠檬酸裂解...

Effect of exogenous trehalose on seed germination and seedling growth of rapeseed under low temperature

In order to increase cold resistance of rapeseed and to improve germination rate and growth, Brassica napus cv. Zhongyouza 19 was used to study on effects of exogenous trehalose under low temperature by seed soaking. Results showed that under 10℃, rapeseed germination was inhibited. Germination potential, germination rate, germination index and vigor index were significantly reduced. Average germination period was significantly extended. Activity of isocitrate lyase, consumption of soluble sugar and soluble protein were significantly reduced during germination. Increase of proline content was turned down. Seedling length, main root length and dry weight and fresh weight of seedlings were significantly reduced. However, after seed soaking with exogenous trehalose, rapeseed growth was significantly increased by higher germination rate and increased root development under cold stress. 10 mmol/L trehalose treatment was the best among different concentrations. By promoting soluble protein and soluble sugar consumptions, increasing proline accumulation, and increasing the activity of isocitrate lyase, the 10 mmol/L trehalose increased the germination rate and germination potential by 19.4% and 61.8%, with the average germination period shortened by 21.7%. It also promoted root growth, increased nutrient content and seedling fresh weight, which enhanced seedling cold resistance. Correlation analysis found that germination indexes had significant correlation with 3 physiological indexes (soluble sugar, soluble protein and proline) after 24 h of seed-soacking. Thus the 10 mmol/L trehalose seed soacking for 24 h might improve the cold resistance of rapeseed. In summary, seed soaking with 10 mmol/L trehalose alleviated the inhibition of low temperature on seed germination by promoting seed energy metabolism and osmotic regulation of rapeseed, improving rapeseed production and its cold resistance.