高海拔地区油茶叶片解剖结构与抗旱性关系研究

Leaf anatomical structure of Camellia oleifera and their relationship with drought resistance in high altitude areas

关键词:  高海拔, 油茶, 叶片, 解剖结构, 抗旱性

Key words:  high altitude, Camellia oleifera, leaf, anatomical structure, drought resistance

摘要:

为探究高海拔地区油茶叶片解剖结构特征及其结构与抗旱性的关系,该研究以前期在贵州省黔东高海拔地区筛选出结实性状优良的35株油茶优株作为试验材料,采用石蜡切片法观察叶片解剖结构,通过描述性及方差分析、相关分析和聚类分析筛选出反映植物抗旱性的叶片结构典型指标,并运用隶属函数综合评价抗旱性,筛选出抗旱性较强的优株。结果表明:(1)油茶栅栏组织细胞层数不等,大多数由2层排列整齐且致密的长柱形细胞组成,极少数有3层。形态指标的变异系数范围为11.15%～26.73%,14项指标中栅海比的变异系数最大。(2)通过聚类分析和相关指数综合排序得出,影响油茶抗旱性的主要指标为栅海比、叶面积、叶脉厚度和栅栏组织厚度。TY05具有最大叶脉厚度599.32 μm,TY16的叶脉厚度最小,为347.53 μm; 叶面积最大的是TY33,为1 766.00 mm²,具有2层栅栏组织细胞,TY08有最大叶片厚度、栅栏组织厚度以及栅海比,分别为673.33 μm、340.26 μm和1.13。(3)通过对比隶属函数综合值大小筛选出抗旱性较强的油茶优株TY26、TY08、TY03、TY27、TY33,可为下一步油茶抗旱品种选育提供材料基础。该研究结果为高海拔地区油茶抗旱品种选育提供了科学依据和理论参考。

Abstract:

In order to explore the anatomical structure characteristics of Camellia oleifera leaves in high altitude areas and the relationship between their structure and drought resistance, In this study, 35 superior individual plants of C. oleifera with excellent fruiting traits, previously selected in the high altitude areas of eastern Guizhou Province, were used as experimental materials, and observed them using paraffin sections. Typical indicators of leaf structure that reflected plant drought resistance were screened out through descriptive and variance analysis, correlation analysis and cluster analysis, and then the membership function was used to comprehensively evaluate drought resistance and select superior individual plants with strong drought resistance. The results were as follows:(1)The number of cell layers in C. oleifera palisade tissue varied. Most were composed of two layers of neatly arranged and dense long columnar cells, and a few had three layers. The coefficient of variation of morphological indicators ranged from 11.15% to 26.73%, and the coefficient of variation of the ratio of palisade tissue to spongy tissue was the largest among the 14 indicators.(2)Through cluster analysis and comprehensive ranking of related indexes, it was concluded that the main indicators affecting the drought resistance of C. oleifera were ratio of palisade tissue to spongy tissue, leaf area, vein thickness and palisade tissue thickness. TY05 had a maximum vein thickness of 599.32 μm, and TY16 had a minimum vein thickness of 347.53 μm. The largest leaf area was TY33, which was 1 766.00 mm² and had two layers of palisade tissue cells. TY08 had the maximum leaf thickness, palisade tissue thickness and ratio of palisade tissue to spongy tissue, which were 673.33 μm, 340.26 μm and 1.13, respectively.(3)According to the membership function comprehensive value, TY26, TY08, TY03, TY27, TY33 had strong drought resistance, which could provide a material basis for the next step of drought resistance variety breeding. The research results provide a scientific basis and theoretical reference for the breeding of drought resistant varieties of C. oleifera in high altitude areas.