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研究了4种多年生根茎型耐旱植物——羊草、高冰草、苇状羊茅和俄罗斯新麦草种子的萌发和根芽生长对不同浓度(0、50、100、150、200、300、400和500mmol.L-1)NaCl胁迫的响应。结果表明,4种牧草种子的发芽率随着盐浓度的增加呈下降趋势。其中,羊草种子耐盐性最差,300mmol.L-1NaCl处理的种子发芽率仅为1.5%,浓度超过300mmol.L-1时,没有种子萌发;高冰草、苇状羊茅和俄罗斯新麦草耐盐性较强,在500mmol.L-1NaCl时发芽率分别为17.3%、20.0%和18.1%。4种牧草的根长和芽长均与NaCl浓度呈极显著的负相关,但表现不同:随着NaCl浓度的增加,俄罗斯新麦草的根长下降速率最快,高冰草最慢;羊草芽长下降速率最快,高冰草最慢;羊草的根/冠比值呈上升趋势,而其他3种牧草则呈下降趋势。说明NaCl胁迫对羊草抑制表现为胚根<胚芽,而后三者则为胚根>胚芽。从种子发芽率和胚生长状况看,在种子萌发期内,羊草种子萌发和苗期的耐盐能力最差,而高冰草、苇状羊茅和俄罗斯新麦草的种子萌发和苗期生长均有较强的耐盐能力。
The effects of germination and root bud growth of four perennial rhizome drought-tolerant plants, Leymus chinensis, Agropyron chinense, Tall Fescue and Russian new wheatgrass, on seed germination and seedling growth under different concentrations (0,50,100,150,200,300, 400 and 500 mmol.L-1) NaCl stress. The results showed that the germination rate of four kinds of pasture seeds decreased with the increase of salt concentration. Among them, the seeds of Leymus chinensis had the poorest salt tolerance, the seed germination rate was only 1.5% when treated with 300mmol.L-1NaCl, and no germination occurred when the concentration exceeded 300mmol.L-1. The salt tolerance of wheat straw was stronger. The germination rate of wheat straw was 17.3%, 20.0% and 18.1% at 500mmol.L-1NaCl, respectively. The root length and shoot length of four species of forage grass had extremely significant negative correlation with NaCl concentration, but with different performance: With the increase of NaCl concentration, the rate of root length decline was the fastest in New Zealand wheatgrass, The buds had the fastest rate of decline and the slowest rate of Agropyron; the root / shoot ratio of Leymus chinensis showed an upward trend while that of the other three species showed a decreasing trend. The results showed that the inhibition of NaCl stress on Leymus chinensis was embryo germ. From seed germination rate and embryo growth status, the seed germination and seedling stage of Leymus chinensis had the worst salt tolerance, while the seed germination and seedling growth of Agropyron chinense, Tall fescue and Russian new wheatgrass Have strong salt tolerance.