单 位：
新疆农业科学院园艺作物研究所/新疆蔬菜工程技术研究中心;新疆农业大学园艺学院
关键词：
番茄;2,4-表芸苔素内酯;盐胁迫;种子萌发
摘 要：
[目的]研究盐胁迫下不同浓度2,4-表芸苔素内酯(2,4-Epibrassinolide,EBR)处理对番茄种子萌发特性和关键酶活性的影响,筛选影响番茄种子萌发及生长发育效果的最佳浓度,为外源EBR的科学应用提供理论依据.[方法]以盐敏感型'M82'和耐盐型'IL-7-5-5'番茄种子为材料,在50 mmol/L的NaCl处理下,添加0.01、0.1和0.5 μmol/L的外源EBR,测定番茄种子在萌发过程中的发芽率、发芽势等形态指标,分析抗氧化酶活性和渗透调节物质含量的变化.[结果]外源EBR处理后的'M82'和'IL-7-5-5'种子的发芽势较盐胁迫处理均提高了 10%~30%以上,种子活力指数均提高了 100-200以上,并且随着EBR浓度升高,2个番茄品种的发芽率、发芽势均呈下降的趋势.0.01 μmol/L EBR处理的'M82'种子胚芽长和鲜重较盐胁迫下分别增加了 94.26%和135.71%;0.1 μmol/L EBR处理的'IL-7-5-5'胚芽长和鲜重较盐胁迫分别增加了 32.48%和14.52%.幼芽体内MDA和SOD、CAT、POD活性显著提升,可溶性蛋白、可溶性糖等渗透调节物质含量显著增加,但不同EBR浓度、不同番茄品种之间的生理指标变化存在明显差异.[结论]外源EBR可以增强在盐胁迫条件下番茄种子萌发过程中调节渗透的能力,增强体内抗氧化系统的活性,膜脂过氧化产物的积累减少,促进番茄种子萌发和生长发育,提高番茄种子萌发期的耐盐性.盐胁迫下0.01 μmol/L的EBR处理对'M82'的缓解效果最佳,0.1 μmol/L对'IL-7-5-5'的缓解效果最佳.
译 名：
Effects of exogenous 2,4-epibrassinolide on seed germination of different salt-sensitive tomatoes under salt stress
关键词：
tomato%EBR%salt stress%seed germination
摘 要：
[Objective]To study the effects of different concentrations of 2,4-Epibrassinolide(EBR)on the germination characteristics and key enzyme activities of tomato seeds under salt stress and determine the optimal concentration of exogenous EBR for tomato seed germination and growth in the hope of providing theo-retical support for the effective application of this plant growth regulator.[Methods]The seeds of salt-sensi-tive tomato'M82'and salt-tolerant tomato'IL-7-5-5'were treated with 50 mmol/L NaCl,and exoge-nous EBR of 0.01,0.1 and 0.5 pmol/L were added to assess tomato seed germination stage of germination rate,germination potential,morphological characteristics,and analysis of antioxidant enzymes activity and os-motic regulation substances content changes.[Results]Compared with salt stress treatment,the germination potential of'M82'and'IL-7-5-5'after exogenous EBR treatment was increased by more than 10%to 30%,and the seed vigor index was increased by more than 100 to 200.With the increase of EBR concentra-tion,the germination rate and germination potential of the two tomato varieties showed a decreasing trend.Compared with salt stress,the seed germ length and fresh weight of'M82'treated with 0.01 pmol/L EBR in-creased by 94.26%and 135.71%,respectively.The germ length and fresh weight of'IL-7-5-5'treated with 0.1 μmol/L EBR increased by 32.48%and 14.52%,respectively,compared with salt stress.The con-tents of osmoregulatory substances such as soluble protein and soluble sugar were significantly increased,and the activities of MDA,SOD,CAT and POD in the sprouts were significantly increased,but there were signifi-cant differences in physiological indexes between different EBR concentrations and different tomato varieties.[Conclusion]In the presence of salt stress,exogenous EBR can enhance the adaptability of tomato seeds to osmotic regulation during germination,improve the efficacy of antioxidant system in vivo,reduce the accumu-lation of membrane lipid peroxidation products,promote the germination and growth of tomato seeds,thus en-hancing the tolerance of tomato seeds to salt during germination.0.01 pmol/L EBR treatment has the best effect on'M82'and 0.1 pmol/L on'IL-7-5-5'under salt stress.
