干旱胁迫下胡麻种子萌发动力学分析及抗旱性鉴定

Analysis of Germination Kinetics and Identification of Drought Tolerance in Flax Seed Under Drought Stress

胡麻是我国重要的经济作物。为了鉴定胡麻种子萌发期的抗旱性,以5个胡麻品种为研究材料,设置5个水分胁迫水平(0,-0.2,-0.4,-0.6,-0.8 MPa)进行发芽实验。研究结果表明:轻度干旱胁迫(-0.2 MPa)对胡麻种子发芽影响较小,甚至提高了个别品种的发芽率或促进根系生长;在中度干旱胁迫(-0.6 MPa)下,种子萌发率明显下降,从最低24.70%(SL297)到最高75.70%(DG241),平均发芽时间(MGT)也延长到36.80~56.60 h,根长降低到正常条件测定值的24.6%~57.8%。5个胡麻品种对干旱胁迫的响应存在基因型差异,其中在-0.8 MPa条件下仅有JN221还能萌发。综合分析多个指标,认为DG241和JN221的抗旱性较好,MG231次之,而SL297的抗旱性最差。

Flax is an important economical crop in China.To evaluate the drought resistance of flax seeds during germination,5 flax varieties were used as research materials and 5 water stress levels(0,-0.2,-0.4,-0.6,-0.8 MPa)were set for germination experiments.The results showed that mild drought stress(-0.2 MPa)had little negative effect on seed germination,and even increased the germination rate of some varieties or promoted root growth.Under moderate drought stress(-0.6 MPa),the seed germination rate decreased significantly,ranging from 24.70%(for SL297)to 75.70%(for DG241);the average germination time MGT prolonged to 36.80~56.60 h,and the root length decreased to 24.6%~57.8%of the value measured in normal condition.There were genotypic differences among the five varieties in response to drought stress,and only JN221 could germinate under-0.8 MPa.Taken together,it seems that the drought tolerance of DG241 and JN221 was the best,followed by MG231,and SL297 was the worst.