不同高粱种质资源对盐胁迫的响应

Responses of Different Sorghum Germplasm Resources to Salt Stress

为建立粒用高粱耐盐评价体系,本研究采用室内模拟及田间鉴定相结合的方法,研究不同高粱对盐胁迫的响应。苗期室内模拟实验表明,材料09305 R、67 B、363 C生长较好、生长速率快,表现出较强的耐盐性;材料10337 B、吉16相对生长指标低,生长缓慢,耐盐性弱,其他材料生长特性介于两者之间;大田实验测定了高粱苗期、拔节期、抽穗期和成熟期叶片的相关酶活性、高粱干物质积累量及苗期叶片Na^(+)、K^(+)含量。结果表明,盐分胁迫条件下SOD、CAT含量与高粱耐盐性呈正相关;干物质积累量为成熟期>灌浆期>拔节期;其中高粱苗期是盐分敏感期,处理之间差异显著,耐盐材料表现出较强的生长能力,提高了干物质的含量;高粱幼苗Na^(+)整体呈升高趋势。盐胁迫条件下,耐盐性好的材料上升的幅度明显小于盐敏材料;高粱叶片K^(+)差异不显著;叶片酶活性与发芽率、发芽势呈极显著的正相关,相关系数分别为0.92、0.97,根长与发芽势之间的相关性也较高,相关系数为0.87;10个特征根中第Ⅰ主成分的贡献率为71.38%,第Ⅰ主成分中发芽率、发芽势和叶片酶活性正值较高,主要反映的种子萌发生长状况及抗性指标,可称其为萌发因子;第Ⅱ主成分的贡献率为11.25%,第Ⅱ主成分中苗长、生长速率正值较高,主要反映高粱的生长状况;前2个主成分的累计贡献率达92.49%;采用聚类分析的方法,将15个高粱亲本材料划分为耐盐、中等耐盐、盐敏3类。

In order to establish a set of salt tolerence material evaluation system for grain sorghum,this study used a combination of indoor simulation and field identification to study the response of different sorghum materials to salt stress.The simulation experiment at the seedling stage showed that the materials 09305 R,67 B and 363 C had good growth,fast growth rate,and strong salt tolerance;materials 10337 B,and Ji 16 had low relative growth indicators,slow growth,and weak salt tolerance.The characteristics of other materials were between the first two;Correclation enzyme activity,dry matter accumulation content in leaves at seedling stage,joint stage,heading stage,maturity stage and Na^(+)content and K^(+)content in leaves at seedling stage were determined in field experiment.Results showed that the content of SOD and CAT was positively correlated with the salt tolerance of the material under salt stress.The dry matter accumulation was in the order of maturity stage>filling stage>joint stage;among them,the sorghum seedling stage was the salt-sensitive stage,and there were significant differences between treatments,and salt-tolerant materials showed higher growth ability to increase the content of dry matter;Na^(+)of sorghum seedlings showed an overall upward trend.Under salt stress conditions,the increase of the salt-tolerant materials was significantly smaller than that of the salt-sensitive materials;The difference K^(+)content of sorghum leaves was not significant;The leaf enzyme activity showed a extremely significant positive correlation with germination rate,germination potential.,and the correlation coefficients were 0.92 and 0.97,respectively.The correlation between root length and germination potential was also high,and the correlation coefficient was 0.87.From the 10 characteristic roots,the contribution rate of the first principal component was 71.38%,of which the germination rate,germination potential and leaf enzyme activity the first main component values were relatively high,which mainly reflected the seed germination and growth status and resistance indicators,which could be called growth factors;The contribution rate of the second main component was 11.25%,and among the second main components,of which the seedling length and growth rate were relatively high,which mainly reflected the growth status of sorghum;The cumulative contribution rate of the first two principal components reached 92.49%;Using cluster analysis,the 15 sorghum parent materials were divided into three categories:salt-tolerant,medium-salttolerant,and salt-sensitive materials.