This experiment used the different concentration (0, 100, 200, 400, 600 mmol·L-1) NaCl solution to treat germinating star grass, grass Kentucky bluegrass, old mans wheat and alkali grass seedlings, and observed their physiological and biochemical changes under the condition of two kinds of processing temperature of 6-15 ℃and 20-25 ℃. The results showed are as follows. Under the different salt concentration stress, soluble sugar content of alkali grass, grass Kentucky bluegrass and star grass tended to increase with the increasing salt concentration. But soluble sugar content of the old mans wheat rose first, and then decreased. Moreover, different temperature had a greater influence on the soluble sugar content of grass seedlings. But under the condition of high salt concentration, the temperature had significant effects on soluble sugar content from seedlings, and the temperature treatment of 6-15 ℃ could significantly increase the soluble sugar content from seedlings. With the increase of salt concentration, the free proline content from four kinds of forage grass accumulated rapidly, and proline content under the condition of room temperature was significantly higher than one under the condition of 6-15 ℃. Salt stress led to the growth of four kinds of forage grass root tip hydrogen peroxide content and cell mortality rate, while temperature treatment of 6-15 ℃ could reduce the accumulation of root tip hydrogen peroxide. Four kinds of forage grass root tip cell mortality rate was prone to rise with the increasing salt concentration, but low temperature of 6-15 ℃ could effectively alleviate the damage of root cell which was caused by salt stress. Under the condition of two kinds of temperature treatments, the plant height of the four grasses began to reduce with the increase of salt concentration, and there was no significant difference in the plant height under the condition of different temperature treatments.%该试验采用不同浓度(0, 100, 200, 400, 600 mmol·L-1)NaCl溶液处理萌发的星星草、草地早熟禾、老芒麦和披碱草幼苗在 6—15 ℃和 20—25 ℃两种温度条件下生理生化的变化.结果表明: ①在不同盐浓度的胁迫下, 披碱草、草地早熟禾和星星草随着盐浓度的提高, 可溶性糖含量呈现增高的趋势;而老芒麦呈现先升后降的趋势.且不同温度处理对牧草幼苗可溶性糖含量影响较大, 但在高盐浓度处理下, 温度对幼苗可溶性糖含量影响极显著, 6—15 ℃处理显著提高幼苗的可溶性糖含量.②随着盐浓度增加, 四种牧草游离脯氨酸含量均迅速积累, 且20—25℃处理下脯氨酸含量显著高于 6—15 ℃处理.③盐胁迫导致四种牧草根尖过氧化氢含量和细胞死亡率的增加, 而 6—15 ℃温度处理可以降低根尖过氧化氢的积累.④四种牧草随盐浓度增加根尖细胞死亡率均有增加的趋势, 6—15 ℃低温可以有效减轻盐胁迫对根细胞的损伤.⑤四种牧草在两种温度处理下随盐浓度增加株高都有所降低, 且在不同温度处理下牧草的株高没有显著性差异.
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