PEG胁迫对几个臭椿种源种子萌发的影响

Effect of PEG on Seed Germination of Ailanthus altissima Provenances

采用0.0%（ck）、2.5%、5.0%、7.5%（w/v）4种浓度的聚乙二醇PEG（6000）对几个臭椿种源种子的萌发进行渗透胁迫处理,结果表明：随着PEG浓度的升高,臭椿种子的发芽率、发芽指数、活力指数均呈下降趋势;发芽后幼苗高、鲜重也呈下降趋势,而根长呈上升趋势;不同种源间的变化趋势相似,但变化幅度有明显差异。综合评价初步认为,河南宝丰种源耐旱性最强,甘肃会宁种源耐旱性较强,宁夏平罗种源耐旱性一般,陕西周至种源耐旱性相对较弱。在实验室环境条件下,臭椿种子萌发及其发芽苗可忍受5.0%~7.5%的PEG渗透胁迫。

Through different PEG concentrations （0.0% ,2.5% ,5.0% ,7.5% ） treating the seed and seedling of different provenance of Ailanthus altissima during their germination and growth period, this paper studied the effect of PEG treatment on the seed germination of tree of heaven. The result showed that with the increasing of PEG concentrations, the germination percentage, germination index, seed vigor index, seedling height growth and fresh weight were all decreased gradually, but root growth was promoted. The change tendencies of different drought resistance among difference provenance were similar, but the range of changes was different remarkably. Synthetically appraised, Henan Baofeng provenance have strongest drought resistance, Gansu Huining provenances have stronger drought resistance, Ningxia pingluo provenances have normal drough resistance Shanxi Zhouzhi provenances have weak drought resistance. According to the result, it could be concluded that A. altissima could tolerant the osmotic stress of 5.0% to 7.5% PEG treatment during sprouting under lab condition.