干旱胁迫对火龙果植株形态及生理指标的影响

Study on the physiological and morphological effects of pitaya under drought stress

为探究不同程度干旱胁迫对火龙果植株形态及生理指标的影响,以大红火龙果植株为材料,采用盆栽控水法,研究干旱处理40、47、54 d后火龙果生理特征的变化及干旱后期火龙果植株的形态变化,探讨火龙果的抗旱特性。结果表明:火龙果具有良好的耐旱性,在干旱胁迫下,可以通过调节体内生理指标来适应干旱环境,不同生理指标的变化趋势在干旱同期存在差异。随着干旱胁迫的加深,火龙果植株生长变缓,茎颜色加深且发生皱缩,主根变短,侧根减少,须根基本消失;相较于对照,各处理的游离脯氨酸(Pro)、可溶性糖含量显著升高,可溶性蛋白、丙二醛(MDA)含量则先降低后升高,过氧化物酶(POD)活性极显著升高后又极显著降低,过氧化氢酶(CAT)活性也表现出先升后降的趋势,超氧化物歧化酶(SOD)活性则持续下降。

In order to explore the effects of different degree of drought stress on the pitaya plant morphological and physiological indexes,with Dahong pitaya plant as material,the morphological and physiological changes of pitaya plant were studied by using pot with water,the drought treatment after 40,47,54 days,respectively. The drought resistance characteristic of pitaya were also studied in this paper. The results showed that pitaya plant has a good drought tolerance,and it could adjust the physiological indexes in the body to adapt the drought conditions under defferent degree of drought stress,the change trend of different physiological indexes was different in drought period. With the deepening of drought stress,pitaya plant grew slowly,colour of stems deepened and surface of stems shriveled,the main root became short and number of root division changed less. Compared with controls,the content of free praline（Pro） and soluble sugar remarkable up-regulated in treatment significantly,content of soluble protein and malondialdehyde（MDA） was lower after first increases,peroxidase（POD） activity significantly increased after significantly reduce,catalase（CAT） activity also show the first trend lowered later,superoxide dismutase（SOD）activity continued to decline.