外源儿茶素浸种对盐胁迫下高粱种子萌发的影响

Effects of exogenous catechins on sorghum seed germination under salt stress

儿茶素是一种多酚类化合物,可促进植物在逆境下的生长发育,减缓逆境胁迫造成的损伤。为探究儿茶素对盐胁迫下高粱幼苗生长发育的影响,本研究以高粱‘河农16’品种为试验材料,通过利用儿茶素浸种处理(儿茶素浓度50μmol/L),对非盐胁迫和盐胁迫下(NaCl浓度100 mmol/L)高粱种子萌发以及形态特征进行测定。结果表明:儿茶素处理可显著提高盐胁迫环境下高粱幼苗的芽长、根长、超氧化物歧化酶活性、脯氨酸、可溶性糖以及叶绿素含量,显著降低过氧化物酶、过氧化氢酶活性和丙二醛含量。进一步的相关性分析结果显示,芽长、根长、芽鲜重、芽干重、根鲜重、根干重、超氧化物歧化酶、脯氨酸、可溶性糖、叶绿素a、叶绿素b、叶绿素总量呈正相关,而与过氧化物酶、过氧化氢酶活性和丙二醛含量呈负相关。综合分析认为,外源儿茶素通过促进高粱幼苗芽长和根长的发育,提高超氧化物歧化酶活性,提高渗透调节物质和叶绿素含量,来缓解盐胁迫对高粱幼苗产生的伤害,促进干物质积累,提高了高粱幼苗的耐盐性。

Catechins are a kind of polyphenolic compounds,which can be used as indirect antioxidants to promote the growth and development of plants under stress and reduce the damage caused by stress.Sorghum is the fifth largest cereal crop in the world,and its growth and development are seriously affected by salt stress.In order to explore the effects of catechins on the growth and development of sorghum seedlings under salt stress,this study took Sorghum‘Henong 16’varieties as experimental materials,and measured the germination and morphological characteristics of sorghum seeds under non-salt stress and salt stress(100 mmol/L NaCl)with catechin leaching treatment(50μmol/L catechin).The results showed that catechin treatment significantly increased the bud length,root length,superoxide dismutase activity,proline,soluble sugar and chlorophyll contents of sorghum seedlings under salt stress,and significantly decreased the activities of peroxidase,catalase and malondialdehyde.Further correlation analysis showed positively correlation of catechin treatment with bud length,root length,bud fresh weight,bud dry weight,root fresh weight,root dry weight,superoxide dismutase,proline,soluble sugar,chlorophyll a,chlorophyll b and total chlorophyll,but negative correlation with peroxidase,catalase activity and malondialdehyde content.According to comprehensive analysis,exogenous catechins can alleviate the damage caused by salt stress on sorghum seedlings,promote dry matter accumulation,and improve the salt tolerance of sorghum seedlings by promoting the development of sprout length and root length,increasing the activity of superoxide dismutase,and increasing the content of osmotic regulatory substances and chlorophyll.