2,4-表油菜素内酯(EBR)对菜用甘薯抗寒生理生化的影响

Effects of 2, 4-epibrassinolide(EBR) on cold resistance-related physiological-biochemical indexes of vegetable sweet potato

菜用甘薯抗寒性能是其在早春及秋冬季作为蔬菜供应的重要制约因素。以徐菜薯1号菜用甘薯为实验材料,通过对甘薯叶进行外源2,4-表油菜素内酯(EBR)喷施处理,探究其对菜用甘薯抗寒生理生化的影响;并对其诱导抗寒的机理进行研究。结果表明,0.1 mg·L^(-1)的EBR处理下甘薯的抗寒性能最佳。与对照相比在8℃低温胁迫下的48 h内,甘薯叶中3种抗氧化酶(CAT、POD和SOD)活性明显高于对照,3种渗透调节物质(可溶性蛋白质、可溶性糖和脯氨酸)中可溶性蛋白的含量有大幅提高,而细胞的损伤指标(电导率和MDA)的数值均低于对照。外源EBR处理提高了甘薯叶中抗氧化酶的活性及渗透调节物质的含量,减少了细胞膜的损伤,增强了菜用甘薯抵抗低温胁迫的能力。

The cold intolerance greatly restricted the supply of vegetable sweet potato in early spring, autumn and winter. By using vegetable sweet potato ＇Xucai-l＇, this research explored the effects of 2, 4-epibrassinolide （EBR） spraying treatment on the cold resistance-related physiological-biochemical indexes in sweet potato leaves under cold stress. Our results showed that spraying 0.1 mg.L-1 EBR was most effective. Within 48 hours of cold stress （8~C）, the activities of three anti-oxidases （CAT, POD and SOD） were significantly higher than those of the control. Of three osmotic adjustment substances （soluble protein, soluble sugar and proline）, the level of soluble pro- tein had greatly increased and the relative electrical conductivity and MAD content which represented the extent of cellular damage were lower compared with the control. Overall, exogenous EBR treatment could increase the activ- ity of anti-oxidases and the content of osmotic adjustment substances, and reduce the cell membrane damage of sweet potato leaves. Spraying of EBR could enhance the resistance of vegetable sweet potato to cold stress.