渗透胁迫下紫花苜蓿生长及ABA受体基因的表达
Growth and Expression of Abscisic Acid Receptor Gene of Alfalfa under Osmotic Stress

以紫花苜蓿不同品种（‘三得利’‘新牧2’‘赛迪5’‘WL656’‘WL168’‘WL903’‘WL712’‘WL343’）为试验材料，研究150 g/L PEG-6000胁迫下，幼苗抗旱性与ABA受体基因表达的关系。结果表明，150 g/L PEG处理下，不同苜蓿幼苗较对照根系缩短（10.58%~15.88%）、苗长减少（18.06%~23.71%）、鲜干质量比降低（24.51%~37.81%）、相对含水量下降（13.31%~16.71%），差异显著；脯氨酸质量分数均显著升高（21.24%~39.04%），抗旱性强弱为：‘WL168’>‘新牧2’>‘WL712’>‘赛迪5’>‘WL343’>‘WL656’>‘WL903’>‘三得利’；‘WL168’的ABA受体 Medtr1g016480和 Medtr5g083270基因的表达量显著升高，二者在根茎叶中的表达量分别为6.10、1.79、3.04和6.51、1.67、1.89，其表达量强弱为：根>叶>茎。渗透胁迫下，苜蓿ABA受体 Medtr1g016480和 Medtr5g083270基因的表达量显著升高，对苜蓿生理生化反应及其生长起到一定的调节作用，进而影响苜蓿的抗旱能力。
Using alfalfa varieties ‘Sanditi’‘Sardi5’‘Xinmu2’‘WL656’‘WL168’‘WL903’‘WL712’ and ‘WL343’ as experimental materials, we studied the relationship between drought resistance and expression of abscisic acid receptor gene of alfalfa under stress of 150 g/L PEG-6000. The results showed that: under 150 g/L PEG stress, the root length(10.58%-15.88%), stem length(18.06%-23.71%), fresh-dry ratio(24.51%-37.81%), relative water content(13.31%-16.71%) of the TM cultured alfalfa were significantly reduced compared with the CK cultured alfalfa;the proline mass fraction of the TM cultured alfalfa were significantly increased compared with the CK cultured alfalfa(21.24%-39.04%). The results showed that,the drought resistance of alfalfa was as follows:‘WL168’>‘Xinmu2’>‘WL712’>‘Sardi5’>‘WL343’>‘WL656’>‘WL903’>‘Sanditi’. Under osmotic stress, the expression of Medtr1g016480 and Medtr5g083270 of abscisic acid receptor gene of ‘WL168’ were higher than the others; the expression of the both in root, stem and leaf were 6.10, 1.79, 3.04 and 6.51, 1.67, 1.89. And the expression strength were as follows: root>leaf>stem. Under osmotic stress, the expression of Medtr1g016480 and Medtr5g083270 were significantly increased. It could affect the ability of drought resistance by regulating the reaction of physiology and biochemistry and the growth.