不同抗旱类型胡麻幼苗对干旱胁迫的生理响应

Physiological Response of Flax Seedlings with Different Drought-resistances to Drought Stress

旨为阐明不同抗旱类型胡麻对干旱胁迫的生理响应规律,以抗旱性由强到弱4个不同抗旱类型的胡麻品种晋亚7号、晋亚10号、晋亚11号、E051-20为材料,采用盆栽控水法,研究了干旱胁迫对不同抗性胡麻生长、膜质过氧化及渗透调节物质含量及过氧化物酶活性的影响。结果表明,随着干旱胁迫程度的加深及时间的延长,幼苗的株高、茎粗及植株的生物量和叶片相对含水量均显著降低;抗旱性强的品种下降幅度明显低于抗旱性弱的品种,依次为晋亚7号<晋亚10号<晋亚11号<E051-20。同时,质膜相对透性、MDA和Pro含量显著升高,并且抗性强的品种Pro含量积累的幅度明显高于抗性弱的品种,增加幅度依次为晋亚7号>晋亚10号>晋亚11号>E051-20。抗性弱的品种MDA和质膜透性的增幅明显高于抗旱性强的品种,可溶性蛋白含量相对稳定。POD酶活性总体呈现上升的趋势,抗旱性强的品种上升幅度明显高于抗性弱的品种。相关性分析结果表明,不同品系胡麻的株高、茎粗与生物量间均呈极显著正相关,与MDA、Pro含量间均呈极显著负相关。因此,可以用Pro、MDA和生物量作为鉴定胡麻幼苗抗旱性的生理指标。

Aiming to elucidate the physiological response mechanism of different drought resistant flax strains to drought stress.In a pot culture,four flax varieties (Jinya 7,Jinya 10,Jinya 11 and E051-20) with different types of drought resistance were used as the materials to study the effects of drought stress on the growth,membrane lipid peroxidation and osmotic adjustment substance content of flax seedlings.The results showed that,with the increase of drought stress and the length of stress time,the plant height,stem diameter,biomass and leaf relative water content of the plant decreased significantly,and the strong drought-resistant varieties decreased significantly less than the weak drought-resistant varieties,which was in turn: Jinya 7<Jinya 10<Jinya 11<E051-20.At the same time,the MDA content,membrane relative permeability and proline content increased significantly,and the accumulation of proline content in resistant varieties was significantly higher than in less resistant varieties,with the order of Jinya 7 > Jinya 10 > Jinya 11 > E051-20.The malondialdehyde and plasma membrane permeability in weak resistant varieties increased more than in strong resistant varieties,and the amount of increase in turn was Jinya 7<Jinya 10<Jinya 11<E051-20.The content of soluble protein was relatively stable.POD enzyme activity generally showed an upward trend,and the increase range of varieties with strong drought resistance was significantly higher than those with weak resistance.The correlation analysis showed that the plant height and stem diameter had very significantly positive correlation with the biomass,but had extremely significantly negative correlation with the contents of MDA and proline.It suggested that the biomass,MDA content and proline content could be used as the indexes to judge the drought resistance of flax seedlings.