干旱胁迫下不同油菜新品种萌发期耐旱性的比较

目的]比较干旱胁迫下不同油菜新品种萌发期耐旱性。方法]以PEG6000为渗透介质模拟干旱条件,对7个不同油菜新品种进行干旱胁迫下种子发芽鉴定,测定其发芽率、发芽指数、活力指数,胚根、胚芽长度,分析不同浓度下油菜种子发芽性状。结果]干旱胁迫下,参试品种在种子萌发期的芽长、发芽指数均显著降低,而根长和发芽率随PEG6000浓度的提高先上升后降低。相关分析表明,低浓度PEG6000有促进油菜种子萌发的作用,高浓度PEG6000有抑制作用,抑制作用随PEG6000浓度增加明显增强,胁迫下的发芽性状可用发芽指数、总长、总鲜重3个指标来表现。结论]不同品种萌发期耐旱性表现不同,根据综合分析可知,陕油803、油研817最耐旱,中双11抗旱能力较强,湘杂油188耐旱程度中等,中油杂16、陕油16、浙油51为干旱敏感品种。

Comparison in Drought Resistance of Different Rapeseed Varieties in Germination Period under Drought Stress

Objective] To compare the drought resistance of different rapeseed varieties in germination period under drought stress.Meth-ods] Through simulating the drought condition taking PEG6000 as permeating medium, germination of rapeseeds were identified under drought stress for 7 new rapeseed varieties.The germination rate, germination index, vitality index, radicle and plumule length were measured, and germination traits at different concentration were analyzed.Results] Under drought resistance, sprout length and germination index of test va-rieties significantly declined.Besides, root length and germination rate firstly rose then declined with increase in PEG6000 concentration.Relat-ed analysis indicated that low PEG6000 concentration is helpful for rapeseed germination, while high PEG6000 concentration inhibits germination. Also, the inhibition action increases with the increase in PEG6000 concentration.Furthermore, the germination rate under drought stress can be characterized by the germination index, total length, and total fresh weight. Conclusions] Different rapeseed varieties have different drought resistance.According to analysis, Shaanyou 803 and Youyan 817 have the highest drought resistance, Zhongshuang 11 has higher drought re-sistance, Xiangzayou 188 has general drought resistance, and Zhongyouza 16, Shaanyou 16 and Zheyou 51 are drought sensitive varieties.