野菊幼苗对自然干旱胁迫的生理响应

Physiological response of Dendrathema indicum seedlings to nature drought stress

用盆栽法对原产于辽宁本溪的野菊(Dendranthema indicum)幼苗在自然干旱胁迫下的生理响应进行了研究。结果表明,渗透调节物可溶性蛋白含量处理期间一直低于对照,后期开始上升并接近对照;可溶性糖与之相反,处理前期急剧上升后期开始下降;丙二醛与相对电导率在处理期间都高于对照,随时间的延长,复水组逐渐接近对照;保护酶系统变化趋势比较一致,都是先上升后下降,最后再上升。本研究认为这种变化前期是植物自我的保护机制,后期的抗氧化酶含量上升可能是植物对环境产生了适应性。综合分析,认为在自然干旱胁迫下野菊有较好的忍耐能力、恢复能力和适应能力,具有较强的抗旱性,可作为良好的园林植物材料应用。

A pot experiment was conducted to study physiological response of Dendrathema znclzcum seeo ings, collected in Benxi of Liaoning Province, to natural drought stress. The experiment included three treatments which were normal watering （ I , CK）, rewatering after 10 days＇ drought stress （Ⅱ ） and 20 days drought stress without watering （Ⅲ）. The results showed that contents of soluble protein （osmotic adjustment substances） in Ⅱ and Ⅲ were lower than that of CK treatment during the initial processing, but later they were up and closed to the CK gradually. However, change of soluble sugar contents was opposite compared with the soluble protein contents. At early stage, soluble sugar contents raised sharply, but then they began to decline. The relative conductivity and MDA contents were higher than those of CK during the processing; but the contents in Ⅱ were close to the CK along with the progress of drought stress. Trends of antioxidant enzyme levels were more consistent; and increased and then decreased, but increased again finally. This paper argues that this change is a plant selfprotection mechanism at begin ning, the late rise in antioxidant enzyme levels may be a plant and environment adaptability. In summary, D. indicum seedlings have better endurance capacity, resilience and adaptive capacity. It has good drought resistance and is a potential landscape plant material.