| 摘要: |
| 【目的】探究不同程度干旱胁迫下云南松幼苗对复水的响应，揭示干旱胁迫云南松幼苗在复水环境下的适应策略，为云南松造林与管理提供理论依据。【方法】以一年生云南松幼苗为试验材料，通过盆栽试验，设置正常水分（CK）、轻度干旱（LD）、中度干旱（MD）和重度干旱（SD）4个处理，持续干旱30 d后复水，复水7 d后测算不同干旱胁迫处理云南松幼苗的株高、地径、生物量等生长指标，以及超氧化物歧化酶（SOD）、过氧化物酶（POD）、过氧化氢酶（CAT）活性和丙二醛（MDA）、可溶性蛋白含量等生理指标，计算其表型可塑性指数，并对各指标进行主成分分析。【结果】①与正常水分（CK）处理相比，复水后LD和MD处理云南松幼苗的株高和地径均无显著差异，而SD处理云南松幼苗的株高和地径分别显著降低了21.09%和19.06%。随干旱胁迫程度的加重，复水后云南松幼苗细根生物量、细根和粗根生物量占比以及根冠比均呈上升趋势，云南松幼苗各器官生物量的分配符合最优先分配理论。②复水后云南松幼苗针叶仍具有较高酶活性。与正常水分（CK）处理相比，复水后LD处理云南松幼苗针叶可溶性糖含量较CK显著下降，MD处理无显著变化；LD和MD处理云南松幼苗针叶的MDA含量均与CK无显著差异；SD处理云南松幼苗针叶可溶性糖和MDA含量分别显著提高了45.35%和88.72%，表明LD和MD处理云南松幼苗受到的损伤可在复水后快速恢复，且恢复程度远远大于SD处理。③茎生物量、根冠比、细根生物量、SOD活性、可溶性蛋白和MDA含量的表型可塑性指数均较大。主成分分析结果表明，云南松幼苗地径、株高、游离脯氨酸、总生物量及POD、SOD、CAT活性的特征向量较大。【结论】复水后不同干旱胁迫处理云南松幼苗生长的恢复程度具有显著差异，轻度和中度干旱胁迫对云南松幼苗造成的伤害可在复水后快速恢复，且恢复程度远大于重度干旱胁迫。云南松幼苗的地径、株高、生物量以及SOD、POD、CAT活性和MDA、游离脯氨酸、可溶性蛋白质含量为响应干旱复水的主要指标。 |
| 关键词: 云南松 干旱复水 干旱胁迫 森林培育 |
| DOI：10.13207/j.jnwafu.2026.01.010 |
| 分类号: |
| 基金项目:国家自然科学基金项目（31960306） |
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| Response of growth and physiological-biochemical characteristics in Pinus yunnanensis seedlings to drought and re-watering |
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LIU Chengyao, LIANG Siyi, WU Junwen, GU Jianyao, DUAN Huaijiao
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College of Forestry,Southwest Forestry University,Kunming,Yunnan 650224,China
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| Abstract: |
| 【Objective】The study aimed to investigate the responses of Pinus yunnanensis seedlings to re-watering under different degrees of drought stress,and their adaptive strategies of P.yunnanensis seedlings during post-drought rehydration,thereby providing a theoretical foundation for afforestation and sustainable management of P.yunnanensis.【Method】A pot experiment was conducted on one-year-old P.yunnanensis seedlings under four drought treatments:normal water (CK),light drought (LD),moderate drought (MD) and severe drought (SD).After 30 days of continuous drought stress,seedlings were rewatered for 7 days.Growth parameters,specifically the height,ground diameter and biomass of P.yunnanensis seedlings,along with physiological traits，such as the activities of superoxide dismutase (SOD),peroxidase (POD),catalase (CAT) activity,malondialdehyde (MDA) and soluble protein were measured.Phenotypic plasticity indices were calculated,followed by the principal component analysis on each index.【Result】① Compared with normal water (CK) treatment,no significant differences were observed in plant height and ground diameter of P.yunnanensis seedlings treated with LD and MD after rewatering.Whereas the plant height and ground diameter of P.yunnanensis seedlings treated with SD were significantly lower than those of CK by 21.09% and 19.06%,respectively.With the increase of drought degree,the fine root biomass,proportions of fine root and thick root biomass,and root/shoot ratio of P.yunnanensis seedlings increased after re-watering,aligning with the optimal partitioning theory for biomass allocation.② The enzyme activities in the needles of P.yunnanensis seedlings retained high after re-watering.The content of soluble sugar in needles of P.yunnanensis seedlings treated with LD was significantly lower than that of CK,but no significant change was observed in MD treatment.Compared to CK,there was no significant difference in MDA content of LD and MD treatments.SD-treated seedlings exhibited 45.35% and 88.72% higher soluble sugars and MDA than CK,respectively,indicating incomplete recovery under SD versus rapid resilience in LD and MD treatments.③ Phenotypic plasticity indices were notably high for stem biomass,root-shoot ratio,and fine root biomass,SOD activity,soluble protein content,and MDA levels.Principal component analysis showed that eigenvetors of ground diameter,plant height,free proline,total biomass,POD and CAT and SOD activity of P.yunnanensis seedlings were higher.【Conclusion】P.yunnanensis seedlings exhibited significant divergence in growth recovery under different drought treatments.Seedlings subjected to light and moderate drought stress exhibited rapid recovery after re-watering,with recovery degree significantly surpassing that under severe drought.Ground diameter and height,biomass allocation,activities of SOD,POD,and CAT,changes in MDA,proline,and soluble protein contents emerged are the main indicators of response to drought-rewatering adaptability in P.yunnanensis. |
| Key words: Pinus yunnanensis drought re-watering drought stress silviculture |
