不同苗龄剑麻(Agave sisalana)生理指标的相关性分析及抗旱性评价

Correlation Analysis on Physiological Indexes and Drought Resistance Evaluation of Different Age of Agave sisalana Seedlings

在元谋金沙江干热河谷区进行盆栽控水试验,模拟干旱胁迫对剑麻H.11648不同苗龄(18个月、12个月、6个月)植株的生理及形态指标的影响。结果表明:(1)大苗在干旱胁迫下,随着干旱胁迫的加剧,叶片含水量随之降低,叶绿素也随之遭到破坏,叶片含水量越低叶绿素破坏越严重。对于叶片MDA含量的变化,Chl a/b及叶片含水量都是这一变化的敏感生理指标。(2)中苗在干旱胁迫下,SOD与POD两种酶协同作用来共同抵制干旱对剑麻的侵害,使其受伤害程度降到最低。(3)小苗在干旱胁迫下,酶系统中POD与SOD两种酶呈协同关系,随着丙二醛含量的增加,剑麻小苗的叶绿素、含水量、生长状况等各方面都受到显著的影响,这对小苗的破坏是全方位的。(4)根据模糊隶属函数法计算出各苗龄阶段剑麻H.11648的抗旱隶属度进行抗旱性比较,得出中苗(苗龄12个月)的综合抗旱能力最强。在对剑麻H.11648的引种过程中,12个月苗龄的剑麻在抗旱生理方面最适合栽种,它的抗旱生理特征能保证其在干热河谷最大程度的存活。

Pot water control experiments were performed in Jinsha River Dry-hot Valleys in Yuanmou. The experiments simulated drought stress on different age of Agave sisalana H.11648 seedlings （18 months, 12 months, 6months）, and studied on the physiological and morphological indices. The results showed that： （1）under drought stress, with the drought stress aggravated, the leaf water content of large seedling decreased, and the chlorophyll was destroyed, chlorophyll a/b and leaf water content were all sensitive physiological indicators to blade malondialdehyde content. （2）Under drought stress, SOD and POD enzyme of medium seedling were synergy to jointly resist drought, to make its level of damage to a minimum. （3）Under drought stress, the two kinds of enzymes POD and SOD of little seedlings were in collaborative relationships. Along with increase of the content of malondialdehyde, chlorophyll content, water content, and the growth of small seedling was significantly affected, the damage to small seedling was comprehensive. （4）According to the fuzzy membership function, the membership degree of drought resistance of each age of seedling A. sisalana H.11648 was calculated, which was concluded that the medium seedling（12 months）had the strongest comprehensive drought resistance capacity. In the process of the introduction of A. sisalana H.11648, the 12 months seedling was the most suitable plant for its drought- resistant physiological, Its drought resistance and physiological features could ensure it lived to a great extent in the dry-hot valleys.