干旱地区农业研究2025，Vol.43Issue(4)：53-62,10.DOI:10.7606/j.issn.1000-7601.2025.04.06
PEG胁迫下γ-氨基丁酸对紫花苜蓿幼苗生长及光合生理的影响
Effects of γ-aminobutyric acid on the growth and photosynthetic physiology of alfalfa seedlings under PEG stress
摘要
Abstract
Five new drought-resistant alfalfa lines(P1,P2,P3,P4,and P5)and five drought-sensitive al-falfa varieties(15354,7657,7470,7740,and 15578)were used as research materials,and-1.6 MPa PEG-6000 was used to simulate drought stress.A total of five treatments of control,drought stress(-1.6 MPa PEG-6000),and spraying 5,10,and 15 mmol·L-1 GABA under drought stress were set up to investigate the effects of exogenous GABA on the growth,development,and photosynthetic characteristics of alfalfa seedlings under drought conditions.The results showed that the morphological indicators of aboveground(plant height,leaf area)and un-derground(root surface area,root volume,root diameter,and root tip number)parts of the test alfalfa showed a first increased and then decreased trend with the increase of GABA concentration and reached the maximum value under the T3 treatment.Compared with T1,the increases were in the range of 7.09%to 20.28%,17.35%to 55.60%,10.77%to 54.37%,8.48%to 30.45%,14.11%to 42.91%,and 15.36%to 100.37%,respectively.Ex-ternal application of different concentrations of GABA improved the drought resistance of alfalfa and significantly de-creased underground biomass,total root length,stomatal limiting value,and water use efficiency,which reached the minimum under T3 treatment,and the decrement varied in the ranges of 24.07%to 59.83%,26.16%to 58.99%,33.76%to 51.44%,and 19.17%to 26.63%,respectively,compared with T1.The membership function analysis showed that GABA had the best mitigation effect on drought in alfalfa under T3 treatment,and the mitiga-tion effect on sensitive materials was more obvious than that of new drought-resistant strains.关键词
苜蓿幼苗/γ-氨基丁酸/PEG胁迫/光合参数/隶属函数Key words
alfalfa seedling/γ-aminobutyric acid/PEG stress/photosynthetic parameters/membership function分类
农业科技引用本文复制引用
杨丽丽,南丽丽,陈娜,马香香,田戈,王永,潘嗣淳..PEG胁迫下γ-氨基丁酸对紫花苜蓿幼苗生长及光合生理的影响[J].干旱地区农业研究,2025,43(4):53-62,10.基金项目
甘肃省重大专项(25ZDNA005) （25ZDNA005）
