盐碱胁迫对两种高粱种子萌发及幼苗生长的影响

摘要

The effects of complex saline-alkaline stress on seeds germination and seedling growth of the fiber sorghum and common sorghum were studied in detail. The features of salt-alkalinized were simulated using 15 kinds of alkali-saline conditions with different salinities and pH obtained by mixing NaCl,Na2SO4 and NaHCO3 in various proportions. The results showed that the germination rate increased in the low alkali-saline environment; the germination rate and germination index of two Sorghums significantly decreased with the increasing of salt concentration and pH values. The accumulative germination rate of fiber sorghum were higher than that of common sorghum,which indicating that fiber sorghum's adaptation to saline environment were slightly higher than that of common sorghum. In the process of sorghum seedling growth,the effects on the growth of radical length and shoots length of various mixed salts with differentalkalinities were similar. With the increasing of salt concentration and pH,shoot length, radical length of seedlings were significantly decreased. The results showed that the salinity has highly significant effect on germination percentage,germination index,shoot length of two sorghums and the interaction of salinity and pH has highly significant effect on radical length.%以纤维高粱和普通高粱种子为材料,将NaCl、Na2 SO4和NaHCO3按不同比例混合,模拟15种盐度和碱度各不相同的复杂盐碱条件,采用培养皿纸上发芽法研究了混合盐碱胁迫对两种高粱种子萌发及幼苗生长的影响,以探讨两种高粱种子和幼苗的耐盐碱能力及在盐碱胁迫下的变化规律.结果表明,低盐低碱环境促进了两种高粱种子的萌发；随着盐碱胁迫的增强,高粱种子的萌发率、萌发指数与对照相比均显著下降,而纤维高粱的累积萌发率下降幅度较普通高粱小,表明纤维高粱对盐渍环境的适应性略高于普通高粱.在高粱幼苗生长过程中,随着盐碱胁迫的增强,两种高粱的幼根和幼芽长均显著下降,且与对照均具有显著性差异.盐度对两种高粱的萌发率、萌发指数、幼苗长均有极显著影响,盐度与pH相互作用对两种高粱的幼根长有极显著影响.