Zafar Zikria, Rasheed Fahad, Ul Haq Ahsan, Ibrahim Faridah Hanum, Afzal Shazia, Nazre Mohd, Akram Seemab, Hussain Zafar, Kudus Kamziah Abdul, Mohsin Muhammad, Qadeer Abdul, Raza Zohaib, Khan Waseem Razzaq
Department of Forestry & Range Management, University of Agriculture, Faisalabad 38040, Pakistan.
Department of Forest Genetics and Forest Tree Breeding, University of Göttingen, 37077 Buesgenweg, Germany.
Plants (Basel). 2021 Aug 6;10(8):1615. doi: 10.3390/plants10081615.
Mitigating climate change requires the identification of tree species that can tolerate water stress with fewer negative impacts on plant productivity. Therefore, the study aimed to evaluate the water stress tolerance of young saplings of and under three soil water deficit treatments (control, CK, 90% field capacity, FC, medium stress MS, 60% FC and high stress, HS, 30% FC) under controlled conditions. Results showed that leaf and stem dry weight decreased significantly in both species under MS and HS. However, root dry weight and root/shoot ratio increased, and total dry weight remained similar to CK under MS in saplings. Stomatal conductance, CO assimilation rate decreased, and intrinsic water use efficiency increased significantly in both species under MS and HS treatments. The concentration of hydrogen peroxide, superoxide radical, malondialdehyde and electrolyte leakage increased in both the species under soil water deficit but was highest in . The concentration of antioxidative enzymes like superoxide dismutase, peroxidase, catalase, and ascorbate peroxidase also increased in both species under MS and HS but was highest in . Therefore, results suggest that saplings depicted a better tolerance to MS due to an effective antioxidative enzyme system.
缓解气候变化需要识别能够耐受水分胁迫且对植物生产力负面影响较小的树种。因此，本研究旨在评估在可控条件下，三种土壤水分亏缺处理（对照，CK，田间持水量的90%，FC，中度胁迫MS，60%FC和重度胁迫，HS，30%FC）下，[具体树种1]和[具体树种2]幼树的水分胁迫耐受性。结果表明，在MS和HS处理下，两个树种的叶片和茎干重均显著下降。然而，在[具体树种1]幼树的MS处理下，根干重和根冠比增加，总干重与CK相似。在MS和HS处理下，两个树种的气孔导度、CO2同化率均下降，内在水分利用效率显著提高。在土壤水分亏缺条件下，两个树种的过氧化氢、超氧阴离子自由基、丙二醛浓度和电解质渗漏均增加，但在[具体树种2]中最高。在MS和HS处理下，两个树种中超氧化物歧化酶、过氧化物酶、过氧化氢酶和抗坏血酸过氧化物酶等抗氧化酶的浓度也增加，但在[具体树种2]中最高。因此，结果表明，由于有效的抗氧化酶系统，[具体树种1]幼树对MS表现出更好的耐受性。
