干旱对毛白杨不同品种幼苗生长和抗氧化系统的影响

Effects of Drought on Seedlings Growth and Antioxidant System of Different Varieties of Populus tomentosa Carr.

为了研究干旱对毛白杨不同品种幼苗的生理生化影响及品种间的差异,以毛白杨的2个品种鲁毛50和易县雌株幼苗为试验材料,研究干旱胁迫对其生长和抗氧化系统的影响以及品种间差异。结果表明:与水分条件良好相比,干旱胁迫显著抑制了2个毛白杨品种株高和基茎的生长速率。2个品种相比,干旱胁迫对鲁毛50的抑制幅度小于易县雌株。干旱胁迫对2个毛白杨品种的抗氧化系统的影响明显不同:干旱胁迫显著累积了易县雌株的丙二醛和过氧化氢含量,同时显著提高了超氧化物歧化酶活性及抗坏血酸过氧化物酶活性水平。但对鲁毛50而言,干旱胁迫对丙二醛、过氧化氢以及2种抗氧化酶几乎没有影响。因此,干旱对2个品种影响不同,鲁毛50比易县雌株表现出更强的抗旱性。

In order to investigate the different physiological and biochemical effects of drought on different varieties of Populus tomentosa and differences between varieties, the effects of drought on growth and antioxidant system in Populus tomentosa Carr. seedlings were studied with two different varieties（Lumao50 and Yixiancizhu）. The results indicated that drought significantly reduced the growth of seedlings height and diameter of two varieties,compared to the wet conditions. In contrast with Yixiancizhu, the inhibition of drought on Lumao 50 was smaller. On the other hand, different responses of two varieties were shown in antioxidant system： drought significantly accumulated MDA and H2 O2 content, and significantly increased the levels of SOD and APX activity in Yixiancizhu;while drought had little effect in the same parameters in Lumao 50. Thus,Lumao 50 was more tolerant to drought than Yixiancizhu.