盐碱胁迫对野生大豆种子萌发的影响

目的 探讨不同盐碱胁迫对内蒙古兴安盟野生大豆种子萌发的影响,为优质野生大豆种质资源的开发利用提供参考。方法 分别利用NaCl溶液（20、40、80、120 mmol/L）、Na₂SO₄溶液（10、20、30、40 mmol/L）、Na₂CO₃溶液（20、40、60、120 mmol/L）对野生大豆种子进行盐碱胁迫处理,以不做盐碱胁迫的处理为对照组（CK）。每种溶液每个浓度设置3个重复,每个重复50粒种子。测定并比较3种溶液处理下野生大豆种子的发芽率、发芽势、发芽指数、活力指数、相对伤害率,以及幼苗的根长、苗长。结果 用NaCl溶液处理野生大豆种子时,80 mmol/L处理组的发芽率、发芽势、发芽指数、活力指数最高,相对伤害率最低;根长、苗长随NaCl浓度增加而降低,80、120 mmol/L处理组根长、苗长显著（P<0.05）低于20、40 mmol/L处理组。用Na₂SO₄溶液处理野生大豆种子时,30 mmol/L处理组发芽率、发芽势、发芽指数、活力指数最高,相对伤害率最低;根长、苗长随Na₂SO₄浓度增加而降低,10 mmol/L处理组野生大豆的根长及苗长最长,与CK差异不显著（P>0.05）。用Na₂CO₃溶液处理野生大豆种子时,随Na₂CO₃浓度的增加,发芽率、发芽势、发芽指数、活力指数呈逐渐降低趋势,相对伤害率呈逐渐升高趋势;120 mmol/L处理组的发芽率、发芽势、发芽指数、活力指数均为0,相对伤害率为100%;20 mmol/L处理组发芽率、发芽势、发芽指数、活力指数与CK差异不显著（P>0.05）。结论 低浓度盐碱胁迫对内蒙古兴安盟野生大豆种子萌发指标影响较小,弱碱、中性盐在一定浓度内可以促进其萌发;不同浓度盐碱胁迫均对野生大豆幼苗生长性状有影响,浓度越高,伤害越大。

Effects of Saline-alkali Stresses on Seed Germination of Wild Soybean

Objective] To investigate the effects of different saline-alkali stresses on germination of wild soybean seeds collected in Hinggan League of Inner Mongolia, and to provide references for the development and utilization of high-quality wild soybean germplasm resources. Method] Wild soybean seeds were treated with saline or alkali stresses using NaCl solution （20, 40, 80 and 120 mmol/L）, Na₂SO₄ solution （10, 20, 30 and 40 mmol/L）, and Na₂CO₃ solution （20, 40, 60 and 120 mmol/L）, respectively, and the seeds with no saline-alkali stress treatments were served as control group （CK）. Three replicates were set for each concentration of each solution, with 50 seeds per replicate. The seed germination rate, germination potential, germination index, vigour index, relative injury rate, as well as the seedling root length and seedling length of the seeds treated with the above three solutions were determined and statistically compared. Result] When the wild soybean seeds were treated with NaCl solution, the highest germination rate, germination potential, germination index and vigour index as well as the lowest relative injury rate were observed in 80 mmol/L treatment group; the seedling root length and seedling length decreased with the increase of NaCl concentrations; the seedling root length and seedling length of 80 and 120 mmol/L treatment groups were significantly （P<0.05） lower than those of 20 and 40 mmol/L treatment groups. When the wild soybean seeds were treated with Na₂SO₄ solution, the highest germination rate, germination potential, germination index and vigour index as well as the lowest relative injury rate were found in 30 mmol/L treatment group; the seedling root length and seedling length decreased with the increase of Na₂SO₄ concentrations; the seedling root length and seedling length in 10 mmol/L treatment group were the longest, with no significant （P>0.05） difference compared to CK. When the wild soybean seeds were treated with Na₂CO₃ solution, the germination rate, germination potential, germination index and vigour index gradually decreased with the increase of Na₂CO₃ concentrations, while the relative injury rate exhibited the adverse trend; the germination rate, germination potential, germination index and vigour index in 120 mmol/L treatment group were 0, and the relative injury rate was 100%; there was no significant （P>0.05） differences in germination rate, germination potential, germination index and vigour index between 20 mmol/L treatment group and CK. Conclusion] Low intensity of saline-alkali stresses minorly affected the germination indexes of wild soybean seeds collected in Hinggan League, and a certain range of intensities of weak alkali or neutral salt were capable of promoting their germination; different intensities of saline-alkali stresses had an effect on the growth traits of wild soybean seedling, the higher the concentrations, the greater the damages.