喷施6-BA对紫花苜蓿耐热性的影响

通过不同浓度和不同喷施次数处理研究了6-苄基腺嘌呤(6-BA)对紫花苜蓿热激胁迫下形态和生理反应的影响.实验结果表明: 喷施6-BA处理,⑴明显增加了紫花苜蓿恢复生长期植株鲜重、单株叶片数和分枝数增加量,其中30mg/L 6-BA处理的作用效果最显著;⑵明显提高了紫花苜蓿热激胁迫下保护酶POD活性,且低浓度喷施两次效果明显;⑶提高了热激过程中和恢复生长期苜蓿叶绿素含量,但差异不显著;⑷明显降低了膜脂氧化产物-MDA含量,其中30mg/L喷施两次与其它处理差异显著.6-BA不同处理均有减轻高温伤害和促进后期生长的作用,但不同浓度、不同喷施次数的6-BA作用效果不同,其中30mg/L浓度喷施两次效果最佳,表明低浓度、多次喷施6-BA 可以有效补充紫花苜蓿因高温造成的激素合成量减少,进而减轻高温伤害.

Effect of 6-Benzyladenine on Heat Tolerance of Alfalfa

Effect of 6-Benzyladenine(6-BA) of different concentrations and treating times on morphological and physiological reaction of alfalfa under heat stress was studied.The results showed that 6-BA treatment enhanced fresh biomass,number of leaf and shoot increased,and 30mg/L had better effect than other treatments;peroxidase(POD) activity was increased,and the effect of lower concentration and spraying twice was better than other treatments;chlorophyll content was increased,but the differences were not significant;malondialdehyde(MDA) content was reduced significantly,and 30mg/L was better than other treatments.According to morphological and physiological reaction to heat stress,the treatment of 30mg/L and spraying twice had better effect on reducing heating damage and promoting regrowth of alfalfa under heat stress than other treatments.This result suggested that lower concentration of 6-BA and spraying over twice could complement hormone reduction induced by heat stress effectively,and that could reduce damage of heat stress on alfalfa.