盐胁迫对赖草种子萌发及其胚生长的影响

在NaCl、Na2CO2和二者混合盐溶液6个不同浓度胁迫下,对赖草种子的发芽率、初始萌发时间、发芽速度以及胚根、胚芽的生长情况等进行了测定和分析。结果表明,赖草种子的发芽率、发芽速度随NaCl溶液浓度的增大先升高后降低,随Na2CO3溶液浓度的增大而降低。其中,50 mmol/L NaCl、5 mmol/L Na2CO3溶液处理下, 赖草种子的初始萌发时间最早,发芽率最高,发芽速度最快。混合盐溶液显著抑制种子萌发,随其浓度的增大,初始萌发时间延后,发芽率、发芽速度显著低于对照。NaCl、Na2CO3和二者混合盐溶液对种子发芽率和萌发进程的影响为混合盐>Na2CO3>NaCl。随着溶液浓度的增大,对胚根生长的抑制作用均不断加大,其影响为Na2CO3>混合盐>NaCl。NaCl、Na2CO3和二者混合盐溶液对胚根生长的抑制作用明显大于对胚芽的抑制作用。

Effect of Salt Stress on Germination of Seeds and Embryo Growth of Leymus secalinus

The effect of the solution of NaCl, Na2CO3 and the mixture of the two salts on the germination characteristic of the Leymus secalinus seeds was studied. The seed germination rate, germination time, germination speed, the length of radicle and plumule with the six designed concentration gradients of the three salts were measured respectively. The results showed as follows: the germination rate and speed of Leymus secalinus seeds increased first, and then decreased with increasing concentration of NaCl; while decreased with increasing concentration of Na2CO3. Under the treatments of 50mmol/LNaCl and 5 mmol/LNa2CO3, the germination original time of Leymus secalinus seeds was the earliest and the germination rate was the highest and the germination speed was the fastest. Mixed salts decreased the germination rate and speed obviously. The comparison of the effect of the three salts on the germination rate and speed was: the mixed salts > Na2CO3 > NaCl. The radicle length decreased with increasing concentration of the three salts. The comparison of the effect of the three salts on the growth of radicle was: Na2CO3 > the mixed salts > NaCl. The negative effect of the three salts on the growth of radical was more greatly than that on the growth of plumule.