Xie Zhi Yu, Zhang Wen Hui
Tianjin Yaohuajiacheng International School, Tianjin 300040, China.
Shaanxi Province Key Comprehensive Laboratory of Fore-stry, Northwest A&F University, Yangling 712100, Shaanxi, China.
Ying Yong Sheng Tai Xue Bao. 2018 Jun;29(6):1759-1767. doi: 10.13287/j.1001-9332.201806.007.
An experiment was conducted to examine the effects of drought and rewatering on growth and photosynthetic physioecological characteristics of Xanthoceras sorbifolia, with 2-year-old seedlings as test materials. There are three treatments, i.e., light drought stress (soil water content 14.3%-16.2%), moderate drought stress(10.6%-12.5%) and severe drought stress (6.8%-8.7%), with the control (21.8%-23.7%). The results showed that with the increases of drought stress, the dry mass per plant, height, basal diameter, leaf number, and leaf area significantly decreased, and length of the main root and the secondary root increased. The gas exchange parameters gradually decreased with the increases of drought stress. The level of P was caused by stomatal factors from 10:00 to 14:00 and by non-stomatal factors after 14:00. Apparent CO use efficiency (CUE) of X. sorbifolia was obviously increased under the moderate and severe drought stress. With the increases of drought stress, F/F, F/F, q, ETR and Ф gradually decreased, and NPQ gradually increased. The changes of all those characters after rewatering were contrary to those after drought. After rewatering for eight days, F/F, F/F, q, ETR, Ф were significantly higher than that of drought stress treated for 30 days. With the increases of drought stress, SOD and POD activities and MDA content gradually increased, but CAT activity decreased, showing the contrary changes after rewatering. After rewatering, the root activity under drought stress increased. X. sorbifolia was strongly resistant to heavy drought stress, and thus could be widely used as energy or garden plants in garden landscaping in North China.
以2年生文冠果幼苗为试验材料，进行了干旱及复水对文冠果生长和光合生理生态特性影响的试验。试验设置3个处理，即轻度干旱胁迫（土壤含水量14.3% - 16.2%）、中度干旱胁迫（10.6% - 12.5%）和重度干旱胁迫（6.8% - 8.7%），以对照（21.8% - 23.7%）为参照。结果表明，随着干旱胁迫程度增加，单株干质量、株高、基径、叶片数和叶面积显著降低，主根和侧根长度增加。气体交换参数随干旱胁迫程度增加逐渐降低。上午10:00至下午14:00，光合速率下降主要由气孔因素引起，14:00之后主要由非气孔因素引起。文冠果的表观CO₂利用效率（CUE）在中度和重度干旱胁迫下明显提高。随着干旱胁迫程度增加，Fv/Fm、Fv'/Fm'、qP、ETR和ФPSII逐渐降低，NPQ逐渐升高。复水后上述各指标变化趋势与干旱处理相反。复水8 d后，Fv/Fm、Fv'/Fm'、qP、ETR、ФPSII显著高于干旱胁迫30 d时。随着干旱胁迫程度增加，超氧化物歧化酶（SOD）和过氧化物酶（POD）活性及丙二醛（MDA）含量逐渐升高，但过氧化氢酶（CAT）活性降低，复水后变化趋势相反。复水后，干旱胁迫下的根系活力增强。文冠果对重度干旱胁迫具有较强的抗性，可在华北地区园林景观中广泛用作能源植物或园林植物。
