【摘要】 【目的】红椎利用价值高，推广应用前景广阔，然而目前红椎林分质量整体不高。磷影响着植物生长发育，磷素缺乏会导致植株生长发育受阻。研究发现，林区土壤磷素普遍较为缺乏，而钙能缓解多种胁迫环境条件下植物遭受的伤害。本研究揭示钙在提升低磷环境下红椎生产力方面的应用潜力，为今后红椎人工林高效培育提供科学参考。【方法】本试验以红椎苗木为试验材料，采用水培法，以KH₂PO₄、CaCl₂分别作为Hoagland营养液中的磷源和钙源，在探究低磷胁迫伤害的基础上，通过设置低磷与不同浓度外源钙交互处理，研究低磷胁迫下钙对红椎苗木生长生理方面的影响。【结果】结果表明：在0.1 mmol·L^-1 KH₂PO₄处理下，苗木生长受到了明显的胁迫伤害，苗高、地径生长量较1 mmol·L^-1 KH₂PO₄处理降低了41%～49%。在1 mmol·L^-1 KH₂PO₄+0～30 mmol·L^-1 CaCl₂处理下，10～30 mmol·L^-1 CaCl₂导致了主根长度、侧根数、叶面积、新叶发生率增加，而根冠比下降，同时叶片中可溶性糖与淀粉含量增加，净光合速率、净光合速率（Pn）、水分利用效率（WUE）、胞间二氧化碳浓度（Ci）增大，蒸腾速率（Tr）、气孔导度（Gs）减小，叶绿体上Ca²⁺定位增强。但整体上，Ca²⁺存在一定剂效性，以20 mmol·L^-1CaCl₂处理下幼苗的生长生理表现最佳。【结论】研究认为，钙能缓解低磷胁迫下红椎苗木受到的胁迫伤害，但钙使用量存在一个最适范围。更多还原

【Abstract】 【Objective】 Castanopsis hystrix has high utilization value and broad application prospect,but its stand quality is not high at present.Phosphorus affects plant growth and development,phosphorus deficiency will lead to plant growth and development blocked.It is found that soil phosphorus is generally lacking in forest areas,and calcium can alleviate the damage of plants under various stress conditions.This study revealed the application potential of calcium in improving the productivity of C.hystrix under low phosphorus environment and provided scientific reference for the efficient cultivation of C.hystrix plantations in the future.【Method】 In this experiment,C.hystrix seedlings were used as experimental materials,KH₂PO₄ and CaCl₂ were used as phosphorus and calcium sources in Hoagland nutrient solution,respectively.On the basis of exploring the damage of low phosphorus stress,the effects of calcium on the growth physiology of C.hystrix seedlings under low phosphorus stress were studied by setting low phosphorus and different concentrations of exogenous calcium.【Result】 The results showed that under 0.1 mmol·L^-1 KH₂PO₄ treatment,the seedling growth was obviously damaged,and the seedling height and ground diameter growth were reduced by 41%-49% compared with 1 mmol·L^-1 KH₂PO₄ treatment.Under the treatment of 1 mmol·L^-1 KH₂PO₄+0-30 mmol·L^-1 CaCl₂,10-30 mmol·L^-1 CaCl₂ increased the length of main root,the number of lateral roots,leaf area,and the incidence of new leaves,while the root-shoot ratio decreased.At the same time,the content of soluble sugar and starch in leaves increased,and the net photo synthetic rate,net photo synthetic rate（Pn）,water use efficiency（WUE）,and intercellular CO₂ concentration（Ci） increased.The transpiration rate（Tr） and stomatal conductance（Gs） decreased,and the Ca²⁺ localization on chloroplast increased.However,on the whole,Ca²⁺ had a certain dose-effect,and the growth physiology of seedlings under 20 mmol·L^-1 CaCl₂ treatment was the best.【Conclusion】 Studies have shown that calcium can alleviate the stress injury of C.hystrix seedlings under low phosphorus stress,but there is an optimal range of calcium use.更多还原