| 摘要: |
| 【目的】探究2和3年生轻木（Ochroma lagopus）在雨季的生长变化以及非结构性碳水化合物（NSC）及其组分在各器官（叶、根）的分配随雨季的变化特征，以揭示不同林龄轻木在雨季的碳分配机制。【方法】从西双版纳2和3年生轻木人工林中选取20 m×20 m代表性样地各6块，每木检尺后从每块样地选择3株标准木，分别于6、7、8、10月测定标准木的树高、胸径，同时取叶样和根样测定NSC及其组分（可溶性糖、淀粉）含量，对所测数据进行双因素方差分析、Person相关性分析以及主成分分析，探究其在雨季（6-10月）的动态变化特征。【结果】①在6-10月，2和3年生轻木树高增长量分别为2.22和1.03 m，胸径增长量分别为3.04和1.36 cm，2年生轻木树高和胸径增长量分别是3年生的2.16和2.24倍。②林龄、采样时间、器官（叶、根）、采样时间与器官的交互作用对轻木可溶性糖、淀粉、NSC含量及可溶性糖/淀粉值具有显著或极显著影响；雨季期间，2和3年生轻木叶和根的可溶性糖、淀粉和NSC含量及可溶性糖/淀粉值均表现出显著的季节性变化，其中2和3年生轻木叶的可溶性糖含量与NSC含量的变化规律大致相同。③2年生轻木树高增长量与根可溶性糖含量呈极显著正相关（P<0.01），胸径增长量与叶、根可溶性糖含量和叶NSC含量呈显著（P<0.05）或极显著（P<0.01）正相关；3年生轻木树高增长量与叶淀粉含量呈显著正相关（P<0.05），胸径增长量与根可溶性糖含量呈显著正相关（P<0.05）。④主成分分析结果显示，根NSC含量对主成分1的方差贡献度最高，叶NSC和叶淀粉含量对主成分2的方差贡献度较高。【结论】2和3年生轻木在雨季的生长和碳水化合物分配存在差异。2年生轻木具有较强的生长潜力，其根部和叶部的可溶性糖及NSC积累与生长发育密切相关；3年生轻木则在碳水化合物的分配上表现出不同模式，叶部淀粉和根部可溶性糖对其生长有重要影响。总体而言，根部的NSC在碳分配中起关键作用，而叶部的NSC和淀粉则在碳水化合物的转化和储存过程中具有重要作用。 |
| 关键词: 轻木 非结构性碳水化合物 雨季 碳分配 |
| DOI：10.13207/j.jnwafu.2026.02.010 |
| 分类号: |
| 基金项目:国家自然科学基金项目（32071688） |
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| Growth of 2- and 3-year-old Ochroma lagopus and change characteristics of non-structural carbohydrates in the rainy season |
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GU Jianyao1, WU Junwen1, DU Guanben2, LIU Chengyao1, DUAN Huaijiao1, XIAO Jiandong1
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1.College of Forestry,Southwest Forestry University,Kunming,Yunnan 650224,China;2.College of Materials Science and Engineering,Southwest Forestry University,Kunming,Yunnan 650224,China
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| Abstract: |
| 【Objective】The growth changes of 2- and 3-year-old Ochroma lagopus and the allocation variations of non structural carbohydrates (NSCs),specifically their components,in organs (leaves and roots) were investigated during the rainy season to reveal carbon partitioning mechanisms in O.lagopus trees of different ages.【Method】Six representative 20 m×20 m plots were selected from the 2- and 3-year-old forest plantations of O.lagopus in Xishuangbanna.After measurements of each tree,three standard trees were chosen from each plot.The height and diameter at breast height of the standard trees were measured in June,July,August,and October.Concurrently,leaf and root samples were also collected to quantify non structural carbohydrates (NSCs) and their components (soluble sugars and starch).The data were analyzed by two-way ANOVA,Person correlation analysis,and principal component analysis to explore their dynamics during the rainy season (June to October).【Result】①From June to October,the tree height increments of 2- and 3-year old O.lagopus were 2.22 and 1.03 m,and diameter at breast height (DBH) increments were 3.04 and 1.36 cm,respectively.The height and DBH increments of 2-year-old trees were 2.1- fold and 2.24-fold higher than those of 3-year-old trees,respectively.②Stand age,sampling time,organ (leaves and roots),and the interaction between sampling time and organ have significant or highly significant effects on the soluble sugar,starch,NSC content,and soluble sugar/starch ratio of O.lagopus.During the rainy season,both 2-year-old and 3-year-old O.lagopus exhibited significant seasonal changes in the soluble sugar,starch,and NSC content,as well as their soluble sugar/starch ratio across leaves and roots.Notably,the patterns of changes in the soluble sugar content and NSC content in the leaves of both 2-year-old and 3-year-old O.lagopus were generally consistent.③The height increments of 2-year-old O.lagopus showed a highly significant positive correlation with root soluble sugar content (P<0.01),and the DBH increments were significantly or highly significantly positively correlated with leaf and root soluble sugar content (P<0.05) and leaf NSC content (P<0.01).For 3-year-old trees, the height increments exhibited a significant positive correlation with leaf starch content (P<0.05),and the DBH increments were significantly positively correlated with root soluble sugar content (P<0.05). ④Principal component analysis showed that root NSC content contributed the most to the variance of principal component 1,whereas leaf NSC content and leaf starch content contributed relatively more to the variance of principal component 2.【Conclusion】This study revealed the differences in growth and carbohydrate allocation between 2-year-old and 3-year-old O.lagopus during the rainy season.The 2-year-old O.lagopus exhibited stronger growth potential,with the accumulation of soluble sugars and NSC in the roots and leaves being closely related to their growth.In contrast,the 3-year-old O.lagopus exhibited a different pattern in carbohydrate allocation,with leaf starch and root soluble sugars playing important roles in its growth.Overall,root NSC content was pivotal in carbon allocation,whereas leaf NSC and starch were essential for carbohydrate transformation and storage. |
| Key words: Ochroma lagopus non structural carbohydrates rainy season carbon allocation |
