灰楸不同无性系单叶形态特征生长动态及其相关性

Different clones of catalpa faygesii bureau simple leaves morphological characteristics growth dynamic and correlation studies

【目的】通过对不同无性系灰楸二年生嫁接苗1个展叶期内的叶片形态特征进行动态研究,旨在探讨灰楸的生长内在机理及形态特征,并对比不同无性系间叶片生长特征的差异,为全面深入了解植物的生长及植物叶片生长特性作以理论基础.【方法】对样本进行动态跟踪调查,采用CAD计算叶面积,称量样本叶鲜干质量,计算叶含水率等.【结果】3个不同灰楸无性系单个叶片的叶面积逐渐持续增大时间为21 d,平均增长幅度达3.66 cm^2/d.叶含水率在展叶期间呈现不规则升降变化,范围为208.76%~370.01%,在展叶第13天时,含水率达到最高值.叶鲜质量随生长的持续处于一直增加的趋势,平均增幅为0.0925 g/d.单叶干质量的动态为先增加后稳定的趋势;其平均增幅为0.0307;干鲜质量比在生长第1~4、7~10、13~16、22~25天期间呈上升趋势,在第4~7、10~13、16~22、25~28天期间呈下降趋势.【结论】灰楸不同无性系间叶形态特征及动态变化基本一致,无性系间无显著差异;通过相关性分析,灰楸单叶面积与叶片鲜质量、叶片干质量,叶片干质量与叶片鲜质量呈极显著正相关关系,相关性可用直线方程表述;含水率与叶鲜、干质量呈极显著负相关关系,相关性可用指数模型表述.

【Objective】 The leaf morphological characteristics of two-year-old grafted seedlings of Catalpa fargesii Bur. from different clones were studied dynamically during a leaf development period. The purpose was to explore the inherent growth mechanism and morphological characteristics of Catalpa fargesii Bur.,and to compare the differences of leaf growth characteristics among different clones,so as to provide a theoretical basis for comprehensively and thoroughly understanding plant growth and leaf growth characteristics.【Method】 The samples were dynamically tracked and investigated. The leaf area was calculated by CAD,the fresh and dry leaf weight was weighed,and the leaf moisture content was calculated.【Result】 The leaf area of single leaf of three different clones increased continuously for 21 days,with an average increase of 3.66 cm^2/d. The water content of leaves increased and decreased irregularly during leaf development,ranging from 208.76% to 370.01%. On the 13 th day of leaf development,the water content reached the highest value. The fresh leaf quality increased with the growth,with an average increase of 0.092 5 g/d. The dry weight of single leaf increased first and then stabilized,with an average increase of 0.0307. The dry-fresh weight ratio increased during the 1~4,7~10,13~16,22~25 days of growth,and decreased during the 4~7,10~13,16~22 and 25~28 days.【Conclusion】 The morphological characteristics and dynamic changes of leaves among different clones of Catalpa fargesii Bur. were basically the same,but there was no significant difference among clones. Through correlation analysis,the single leaf area of Catalpa fargesii Bur. was positively correlated with fresh and dry weight of leaves,and the dry weight of leaves was positively correlated with fresh weight of leaves. The correlation could be expressed by linear equation;the water content was negatively correlated with fresh and dry weight of leaves,and the correlation could be expressed by index model.