不同苜蓿品种幼苗对干旱胁迫的生理响应

Physiological Responses of Different Alfalfa Varieties Seedlings to Drought Stress

目的:确定干旱条件下紫花苜蓿的抗旱能力及其生理机制。方法:于2016年在安徽凤阳以金皇后、阿尔冈金、苜蓿王、超人和德宝5个品种为材料进行盆栽试验,调查了干旱处理前后不同紫花苜蓿品种幼苗的植株形态变化,测定了植株样品中的可溶性糖含量、游离脯氨酸含量、丙二醛含量和过氧化氢酶活性等生理指标,比较了不同紫花苜蓿品种的抗旱指数。结果:干旱处理后植株株高和鲜质量显著降低了13%~32%,体内生理指标则显著增加了12%~130%。结论:金皇后和阿尔冈金抗旱能力较强,另三个品种抗旱能力较弱。抗旱力强的品种在干旱处理后可溶性糖含量、游离脯氨酸含量、过氧化氢酶活性增加更多,而抗旱力弱的品种丙二醛含量更高。

Objective： In order to determine the drought resistance of alfalfa under drought conditions and its phys- iological mechanism. Methods： Pot - cultivated experiments were carried out in Fengyang, Anhui Province in 2016. Five varieties were used in the experiment. The contents of soluble sugar, free proline, malondialdehyde and activity of catalase were measured in the plant samples. The drought resistance index was compared between different alfalfa varieties. Results： The results showed that the plant height and fresh weight were significantly de- creased by 13 % ~ 32 % in drought treatments, and the physiological indics in the plant increased significantly by 12 % to 130 %. Conclusion： By comparing the resistance indice of different varieties, we concluded that the cultivar ＇ Gold Queen＇ and ＇ Algonquin＇ had strong resistance to drought and the other three varieties had weak resistance. The content of soluble sugar, free proline and catalase increased with the increase of resistance to drought, but the content of malondialdehyde decreased.