盐碱胁迫对紫花苜蓿根系Na+、K+离子流速的影响

中国盐碱地形成,大部分与土壤中碳酸盐的累计有关,因而碱化度普遍较高。在盐碱地再利用过程中,简单说,可以分为轻盐碱地、中度盐碱地和重盐碱地。利用NaCl、Na₂SO₄、NaHCO₃、Na₂CO₃4种盐,按不同比例配比,人工模拟盐碱地中轻盐碱地盐碱度、中度盐碱地盐碱度和重盐碱地盐碱度。选用耐盐苜蓿品种金皇后、中度耐盐苜蓿品种阿尔冈金、敏感苜蓿品种敖汉,分别进行盐碱胁迫实验;通过非损伤微测技术检测苜蓿根系Na⁺ 、K⁺离子流变化,比较轻盐碱度、中度盐碱度和重盐碱度胁迫下3个耐盐苜蓿品种的离子流速差异。结果显示:在盐碱胁迫下,耐盐碱品种金皇后Na⁺离子流速外流速度比中度耐盐品种阿尔冈金要高,且均表现为外流;敏感品种敖汉在中度盐碱环境下由外流转变为内流,并出现萎蔫迹象。3个苜蓿品种的K⁺离子流速都发生变化,表现为外流,但流速变化各不相同且无明显的规律性。所以,在盐碱抗逆性中紫花苜蓿可以通过Na⁺离子流速控制来适应盐碱环境。

Influence of Salt Stress on the Ion Flow Velocity of the Na+ and K+ion in Alfalfa Root

The formation of saline is relation to carbonate’s cumulative, so the degree of alkalisation is generally higher in the saline. Simply put, the saline can be divided into light , moderate and heavy saline salinity in the use process. In this study, we use NaCl, Na₂SO₄, NaHCO3, Na₂CO₃ to artificially simulate the light, moderate and heavy saline according to the different proportions. Meanwhile, we select the salt-tolerant alfalfa variety: God Empress, moderately tolerant alfalfa variety: Algonquin, sensitive alfalfa variety: Aohan to conduct saline stress experiments. Ion flow variation is detected by using Non-invasive Micro-test Technique for the Na +, K + ion in the alfalfa roots, and the Na ⁺, K ⁺ ionic velocity differentia of God Empress, Algonquin, Aohanare under light salinity, moderate salinity and heavysalinity stress is compared. The results show that: under salinity stress, God Empress Na ⁺ ion velocity rate is faster than Algonquin, and they show outflows; Aohan under the moderate saline environment varies from outflow to internal flow, and shows signs of wilting. The three varieties alfalfa of K⁺ ion velocity all chang, but the variation of the ion velocity are not the same and without obvious regularity, and display outflow. Therefore, in the saline alkali tolerance, Alfalfa may adapt to the saline environment by controlling Na+ ion velocity.