SA浸种对盐胁迫下小麦种子萌发和幼苗生长的影响  

Effects of Seed Pre-soaking with Salicylic Acid on Seed Germination and Seedling Growth of Wheat under Salt Stress

作　　者：刘亚栋[1] 张长峰[1] LIU Ya-dong ZHANG Chang-feng(Shandong Institute of Commerce and Technology, Jinan 250103, Shandong, China)

机构地区：[1]山东商业职业技术学院,中国山东济南250103

出　　处：《生命科学研究》2017年第3期244-250,共7页Life Science Research

基　　金：山东省自然科学基金资助项目(ZR2012CM010)

摘　　要：以小麦盐敏感品种鲁麦15为材料,研究了外源水杨酸(salicylic acid,SA)浸种对100 mmol/L NaCl胁迫下小麦种子萌发和幼苗生长的影响。研究结果表明:盐胁迫下,无论经SA浸种还是未经SA浸种,小麦幼苗的生长均受到明显抑制,干、鲜重显著下降;0.1 mmol/L、0.2 mmol/L和0.3 mmol/L SA溶液浸种均能显著缓解NaCl胁迫对小麦幼苗生长的抑制,其中以0.2 mmol/L SA溶液浸种预处理效果最好。实验中,0.2 mmol/L SA浸种可显著提高盐胁迫下小麦种子β-淀粉酶的活性和吸胀速率。此外,与未经SA浸种的盐胁迫小麦幼苗相比,0.2 mmol/L SA浸种的盐胁迫小麦幼苗整株的干、鲜重显著增加,幼苗体内Na^+含量降低,K^+含量和K^+/Na^+比值显著提高;同时,小麦幼苗叶片中超氧化物歧化酶(superoxide dismutase,SOD)、过氧化氢酶(catalase,CAT)、过氧化物酶(peroxidase,POD)活性升高,而丙二醛(MDA)含量则显著降低。由此可以得出,SA浸种能有效提高盐胁迫下小麦幼苗体内K^+/Na^+比值,提高SOD、CAT和POD的活性,减轻膜脂过氧化程度,以缓解盐胁迫对小麦幼苗生长的抑制作用,从而提高耐盐性。Seeds of Triticum aestivum L. （LM 15）, a salt-sensitive wheat cultivar, were pre-soaked with salicylic acid （SA） to examine the effect of SA pretreatment on the germination and seedlings growth under 100 mmol/L NaC1. The results showed that, whether the seeds were pre-soaked with SA or not, the growth of wheat seedlings was significantly inhibited under salt stress and the seedling fresh weight （FW） or dry weight （DW） was dropped notably. However, 0.1 mmol/L, 0.2 mmol/L and 0.3 mmol/L SA pre-soaking significantly allevi- ated the growth inhibition of wheat seedlings under NaC1 stress, and 0.2 mmol/L SA pre-soaking gave rise to the best alleviative effect. In the experiment, 0.2 mmol/L SA pre-soaking significantly alleviated the β-amy- lase activity and imbibition rate of wheat seeds under salt stress. In addition, wheat seedlings that seeds were pre-soaked with 0.2 mmol/L SA had more FW and DW, lower Na＋ concentration, higher K＋ concentration and K＋/Na＋ ratio, higher activities of SOD, CAT and POD along with lower MDA content of leaves. These re- suits indicated that seeds pre-soaking with SA increased sah-tolerance of wheat seedlings by maintaining a higher K＋/Na＋ ratio, enhancing SOD, CAT and POD activities and reducing the degree of membrane lipid peroxidation.

关 键 词：小麦 盐胁迫 水杨酸(SA) 种子萌发 膜脂过氧化 

分 类 号：QQ945.78[农业科学—作物学] S512.1