3种决明属种子萌发对干旱胁迫的响应及其抗旱性评价

Evaluation of the Response against Drought Stress and Drought Resistance of the Germination of 3 Species of Cassia

以3种决明属种子为材料,研究了不同质量分数的PEG-6000胁迫对其种子萌发的影响,并对其抗旱性进行评价。结果表明:干旱对3种决明属种子的萌发有显著影响;不同质量分数的干旱胁迫对该属种子的相对发芽率、相对发芽势、相对发芽指数、相对活力指数、相对苗长和相对苗重均存在抑制作用;低质量分数的PEG-6000干旱胁迫对相对根长具有一定的促进作用,而高质量分数会抑制幼苗的相对根长。通过隶属函数法综合评价认为,3种决明属种子的抗旱性顺序为草决明>望江南>伞房决明。

Controlled experiments were conducted to investigate the effect of drought stress by different concentrations of PEG-6000 on seeds germination of 3 species of Cassia.The results showed that the relative germination rate, relative germination vigor, relative germination index, relative vigor index, relative seedling length and relative seedling weight of Cassia all decreased significantly with the increase of PEG-6000 concen-tration.Low concentrations of PEG promoted relative root length,but high concentrations of PEG restrained rel-ative root length.According to the evaluation of the above seven indicators with subordinate function, the drought-resistance sequence of the 3 species of Cassia from high to low was：Catsia tora Linn〉Cassia occiden-talis〉Cassia corymbosa.