44个紫花苜蓿品种的酸铝适应性与耐受性评价

为了解紫花苜蓿在贵州地区的适应性及耐酸铝胁迫机理，以44份紫花苜蓿品种为研究对象，研究紫花苜蓿处于酸铝胁迫下的生理变化，并揭示其生理变化与耐酸铝胁迫间的关系。利用基因与环境互作模型对两个地点1年的紫花苜蓿进行产量分析，筛选出阿尔冈金、新疆大叶苜蓿、Trifecta、Vernal和中牧1号苜蓿5个耐酸铝强适应品种。利用敏感型UC-1465和耐受型阿尔冈金进行酸铝胁迫试验。结果表明：相同处理下，耐受型紫花苜蓿的电导率、相对铝含量、死亡率显著低于敏感型；紫花苜蓿对酸铝胁迫的响应主要通过柠檬酸、苹果酸、乙酸、酒石酸、反丁烯二酸和草酸的显著（P<0.05）增加来体现，其中苹果酸的合成和分泌增多可能是其耐酸铝胁迫的重要原因。

Acid-aluminum adaptability and tolerance evaluation of 44 alfalfa cultivars

The aims of this study were to explore the range of adaptability of Medicago sativa cultivars in Guizhou to acid-aluminum conditions， and to determine which physiological factors are related to tolerance of these conditions. We selected 44 alfalfa varieties for a one-year field experiment. A genotype×environment interaction model was used to analyze the yield of alfalfa at two locations in one year， and five acid-tolerant and aluminum-adaptive varieties were identified： Algonquin， M. sativa cv. xinjiangdaye， Trifecta， Vernal and Medicago varia cv. Zhongmu No.1. Aluminum-acid stress experiments were carried out using the sensitive variety UC-1465 and the tolerant variety Algonquin. It was found that， under the same treatment， the electrical conductivity， relative aluminum content， and mortality rates were significantly lower in the tolerant alfalfa cultivar than in the sensitive alfalfa cultivar. The response of alfalfa plants to acid-aluminum stress was mainly reflected by significant （P<0.05） increases in citric acid， malic acid， acetic acid， tartaric acid， fumaric acid， and oxalic acid contents. The increased synthesis and secretion of malic acid may be an important factor in resistance to acid and aluminum stress.