干旱胁迫对樟叶越橘叶片生理特性的影响

Effect of Drought Stress on Physiological Characteristics of Vaccinium dunalianum Leaves

以盆栽樟叶越橘(Vaccinium dunalianum Wight)为试材,采用自然干旱方法停水不同天数处理植株,探究了干旱胁迫对樟叶越橘叶片生理特性的影响,为进一步研究樟叶越橘对干旱胁迫的适应性和耐受性机制提供理论参考。结果显示:在干旱胁迫不同处理时期,樟叶越橘叶片中叶绿素含量呈先上升后下降趋势,且在第7天时达到最高(0.62 mg/g);而其代表膜脂过氧化程度的MDA含量整体上升,并在第28天达到最大值,为24.22μmol/g;Pro含量呈先上升后下降再升高的趋势,均显著高于CK组;SS含量呈现上升趋势,第28天达到峰值且与CK组差异显著;SOD活性呈先增加后降低的趋势,而POD活性表现为升-降-升的趋势。表明樟叶越橘在干旱胁迫初期通过调节渗透调节物质含量和抗氧化酶活性等以抵御干旱伤害,而干旱胁迫后期,保护酶系统和细胞膜受损较严重,影响了植物正常生长。

In order to further study the adaptability and tolerance mechanism of Vaccinium dunalianum to drought stress,this study used potted V.dunalianum plants as test material to compare the effects of different days of drought stress on the physiological characteristics.The results showed that during different drought stress treatment periods,the chlorophyll content of V.dunalianum leaves increased first and then decreased,and reached the peak(0.62 mg/g)on the 7th day.The content of MDA,which represents the degree of membrane lipid peroxidation,kept increasing and reached the highest value of 24.22μmol/g on the 28th day.With the prolongation of drought stress time,the Pro content of V.dunalianum leaves shows a trend of first increasing,then decreasing,and then increasing,which was significantly higher than that in CK group.SS content showed an upward trend,reached the peak on the 28th day,which had significant difference with the CK group.With the extension of drought stress time,SOD activity of V.dunalianum leaves increased first and then decreased,while POD activity showed a trend of up-down-up.The results of this study indicated that V.dunalianum could resist drought damage by adjusting their osmotic adjustment substance content and antioxidant enzyme activity in the early stage of drought stress,while in the later stage,the damage of protective enzyme system and cell membrane was serious,which affected the normal growth of V.dunalianum plants.