贵州特有植物美丽红山茶水分胁迫的生理响应

Physiological response of water stress of Guizhouendemic plant Camellia delicate

关键词:  美丽红山茶  水分胁迫  生理响应  抗逆性  特有植物

Key words:  Camellia delicata  water stress  physiological response  stress resistance  endemic plant

摘要:

采用水分抗逆性指标主成分分析法,选择4年实生苗,测定和评价了连续30 d水涝和干旱胁迫的生理响应。结果表明:(1)水涝处理的叶片生长旺盛,光泽度和观赏性无明显变化,叶片相对含水量、MDA含量、SOD活性、POD活性、CAT活性的变化差异在5%以内,土壤含水量增加3.47%,细胞膜透性减少1.59%,短期水涝对美丽红山茶伤害不明显;(2)随着干旱时间延长,新叶卷缩、老叶脱落,土壤含水量、叶片相对含水量随时间呈负相关缓慢减少,细胞膜透性呈正相关缓慢增长,但复水10 d后可恢复正常生长,无明显生理变化响应;(3)SOD活性和MDA含量分别增加了0.66%和5.31%,POD活性随干旱时间上下波动而增加6.47%,CAT活性随干旱时间延长而增加,20 d增加33.33%达最大值20.8 U·g^-1·min^-1。在抗性生理中,维持膜稳定性的叶片含水量、POD和CAT的变化对抗旱能力大小起主要作用。

Abstract:

Camellia delicata is Guizhou endemic species and ornamental tree,so research on water stress is very important for the popularize. The paper studied 4-years seedlings,by principal components analysis method of physiological index,tested and evaluated the physiological response of waterlogged for 30 days and water stress. The results were as follows:(1)When the plants waterlogged,leaves grew well,there were no obvious changes in gloss and ornamental. The differences of leaf moisture content,MDA,SOD,POD and CAT were under 5%,soil moisture content increased 3.47%,cell membrane permeability decrease 1.59%. The damage to C. delicate short-term waterlogged was not obvious;(2)With drought time extension,new leaves were shriveled,old leaves broke off plant. Soil moisture content and leaf moisture content were negatively related to drought period,decreased slowly. The cell membrane permeability was positively correlated with drought period,grew slowly. But the plants returned to normal growth after watering 10d,and had not obvious physiological change response;(3)The SOD and MDA increased respectively 0.66% and 5.31%,POD fluctuated and increased 6.47% with drought time. CAT activity also increased 33.33% with drought 20 days,reached maximum 20.8 U·g^-1·min^-1. In the resistant physiology,which played the leading role in drought were leaf moisture content,POD,CAT.