复合盐胁迫对小麦萌发的影响及耐盐阈值的筛选

Effects of Composite Salt Stress on Germination of Wheat and Screening of Salt Tolerance Thresholds

为了解Na2SO4和NaCl组成的复合盐对小麦萌发期的胁迫效应,选择5个耐盐性不同的春小麦品种进行复合盐胁迫处理,研究在不同浓度复合盐胁迫下,春小麦品种在发芽势、发芽率、苗高、根数、主根长和苗鲜重等指标上的差异,并采用多重比较和回归分析筛选最适复合盐萌发期处理浓度。结果表明,随着复合盐各盐分浓度升高,小麦萌发期各指标的相对耐盐系数急剧下降,且发芽势、发芽率、苗高、主根长和苗鲜重在不同浓度处理间差异极显著;但复合盐对小麦根数的影响较小,在低盐浓度下差异不显著。在Na2SO4浓度为0.05mol.L-1、NaCl浓度为0.1mol.L-1时,5个品种的发芽率、苗鲜重、苗高的相对耐盐系数在50%左右,发芽势和主根长趋近于30%,同时种子保持较高的活力,可以作为小麦萌发期耐盐鉴定的适宜复合盐胁迫浓度。

To study the effects of mixed salts with Na2SO4 and NaCl on spring wheat,the seeds of 5 spring wheat varieties with different salt tolerance were treated with different concentrations of mixed salts composed of Na2SO4 and NaCl during germinating stage.The germination energy,germination percentage,plant height,root number,main root length and fresh weight of seedlings were investigated,and the most suitable salt concentration was screened by multiple comparison and regression analysis.The results indicated that every morphological index of spring wheat dropped rapidly with the increasing of the salt concentration,and significant differences in germination energy,germination percentage,plant height,main root length and fresh weight of seedlings were observed among different salt treatments.There were no significant differences for root number under the low salinity.The relative salt tolerance coefficients of germination percentage,plant height and seeding wet weight was about 50%,and that of germination energy and main root length was 30% at the mixed salt of 0.05 mol·L-1 Na2SO4 and 0.1 mol·L-1 NaCl,while higher vitality of wheat seedlings could bemaintained.Therefore this concentration might be used for detecting the salt tolerance of spring wheat during geminating stage.