碳酸钠胁迫对甜高粱种子萌发和幼苗期生理特性的影响

摘要

以甜高粱品种"能饲Ⅰ号"为试验材料,研究了甜高粱种子萌发期和幼苗期对Na2CO3胁迫的生理响应.结果表明:在不同浓度Na2CO3胁迫下发芽率、发芽势、活力指数、胚根长度和胚芽长度与对照相比差异均显著.在Na2CO3胁迫浓度低于30 mmol/L时,对甜高粱幼苗根系活力的提高具有一定的促进作用;随Na2CO3 胁迫浓度的增加,丙二醛、脯氨酸含量呈上升趋势,且当其浓度增加到100mmol/L时,脯氨酸含量急剧上升,表明脯氨酸在甜高粱抵抗盐碱胁迫方面发挥重要作用.而SOD比活力随Na2CO3胁迫浓度的增加呈现逐渐下降的趋势.%Effects of Na2CO3 stress on seed germination and seedling physiological characteristics of sweet sorghum were studied.The results show that germination rate, germinability, vital index, length of radicle and length of germ have significant difference compared with the control respectively under various concentration of Na2CO3.Root activity of sweet sorghum seedlings increased when concentration of Na2CO3 was less than 30 mmol/L, and with the concentration of Na2CO3 increasing, the content of malonaldehyde (MDA) and proline increased significantly.When concentration of Na2CO3 reached 100 mmol/L, the content of proline increased sharply.This result indicates that proline may play an important role in resisting the saline-alkaline stress in sweet sorghum seedlings.In contrast, activity of Superoxide Dismutase (SOD) decreased when concentration of Na2CO3 increased.