35个白榆优良家系种子萌发期耐盐碱性评价

Comprehensive Evaluation of Saline-alkali Resistance in Seed Germination Period of 35 Ulmus pumila Families

在全国范围内收集的35个优良白榆(Ulmus pumila)家系种子为试验材料,以150 mmol/L NaCl和50 mmol/L NaHCO3进行胁迫处理,测定萌发指标,应用隶属函数法进行耐盐碱性综合评价。此外,还研究不同盐碱浓度对其中3个不同耐盐碱性家系萌发的影响,并计算耐盐碱阈值。结果表明,发芽指数、发芽势、根长、芽长和鲜质量适宜表征白榆萌发期耐盐性,发芽势、根长、芽长和鲜质量适宜表征耐碱性,其中根长和芽长表征耐盐和耐碱性均效果最好;35个家系中萌发期高耐盐、中耐盐、低耐盐和不耐盐家系分别为2个、8个、13个和12个,高耐碱、中耐碱、低耐碱和不耐碱家系分别为3个、9个16个和7个;综合比较发现中高耐盐碱8个家系0102、037、07、080、087、094、54和82003,不耐盐碱3个家系0120、047和0132;根据萌发期相对生长量,计算出家系087、064和0132耐盐阈值(161.60、89.78和76.28 mmol/L)和耐碱阈值(66.17、53.52和31.20 mmol/L),与通过隶属函数法评价所得结果一致。因此,隶属函数法评价白榆萌发期耐盐碱性可靠性高,且白榆家系间耐盐碱性遗传差异大,具有萌发期耐盐碱品种选育潜力。

Seeds of 35 Ulmus pumila families collected from cross China were used as experimental materials,150 mmol/L NaCl and 50 mmol/L NaHCO3 were applied as stress treatments,germination indexes were determined,and salt and alkali tolerance was evaluated comprehensively by a subordinate function method.Additionally,the effects of different saline-alkali concentrations on the germination of three different salt-alkali tolerant families were studied,and the salt-alkali tolerance threshold was calculated.The results showed that the germination index,germination energy,root length,shoot length and fresh mass were suitable to characterize the salt tolerance of Ulmus pumila at the germination stage,while germination energy,root length,shoot length and fresh mass were suitable to characterize the alkali tolerance,among which root length and shoot length were the best indicators for characterizing the salt tolerance and alkali tolerance.2,8,13 and 12 families showed high,medium,low and no salt tolerance at the germination stage,and 3,9,16 and 7 families showed high,medium,low and no alkali tolerance,respectively.Through comprehensive comparison,eight families(0102,037,07,080,087,094,54 and 82003)with moderate and high salt-alkali tolerance and three families(0120,047 and 0132)with no salt-alkali tolerance were found.Salt tolerance thresholds(161.60,89.78 and 76.28 mmol/L)and alkali tolerance thresholds(66.17,53.52 and 31.20 mmol/L)were calculated for the families 087,064 and 0132 based on relative growth during germination period,and were consistent with the results obtained by the subordinate function method.Therefore,the subordinate function method had high reliability in evaluating the salt and alkali tolerance of Ulmus pumila at the germination stage,and there were great genetic differences among different Ulmus pumila families,indicating the potential for breeding varieties with salt-alkali tolerance at the germination stage.