镉胁迫对甘蓝型油菜种子萌发和幼苗生长的影响

为了解重金属镉对甘蓝型油菜种子的萌发和幼苗的生长的影响,该研究测量了25个不同遗传背景的甘蓝型油菜在4个镉胁迫处理浓度(0、1、5和10 mg/L)下的发芽势、发芽率、苗长、主根长、苗鲜重、苗干重等指标.结果表明,不同材料对镉胁迫的反应不同.随着镉胁迫浓度的增加,相对发芽势和相对成苗率呈现先增长后降低的趋势,在5 mg/L时最高.镉胁迫对幼苗生长的影响表现为根长>苗长>苗鲜重>苗含水量.在不同浓度镉胁迫下,不同甘蓝型油菜品系间的相对根长、相对苗长、相对苗鲜重和相对苗含水量差异达极显著水平,而相对发芽势和相对成苗率,除5 mg/L浓度下的相对成苗率达极显著水平外,品系间差异都不明显,说明幼苗生长比种子萌发对重金属胁迫更为敏感.

Effects of Cadmium Stress on Seed Germination and Seedling Growth of Brassica napus L.

To investigate the effects of the heavy metal cadmium (Cd) on seed germination and seedling growth of Brassica napus L., 25 B. napus lines with different genetic background were treated with four concentrations (0, 1, 5 and 10 mg/L) of Cd, and then, their germination potential, germination rate, seedling length, main root length, seedling fresh weight, and seedling dry weight were measured. The results showed that the response of the B. napus lines to Cd stress was different.With the increase of Cd concentration, the relative germination potential and relative seedling rate increased first and then decreased, and reached the maximum levels when the Cd concentration was 5 mg/L. The inhibitory effects of Cd stress on seedling growth indices in a decreasing order were root length >seedling length >seedling fresh weight>seedling water content. There were extremely significant differences in the relative root length, relative seedling length, relative seedling fresh weight and relative seedling water content among the B. napus lines treated by different concentrations of Cd, while there were no significant differences in the relative germination potential and relative seedling rate among the lines, except that the relative seedling rate was significantly different among the lines treated by 5 mg/L Cd. The results suggested that seedling growth was more sensitive than seed germination to heavy metal stress.