采用石蜡切片技术对采自浙江的9 个品系61 个油茶(Camellia oleifera Abel)品种的叶片及中脉横切面解剖特征进行了观察,在此基础上采用聚类分析法对品种间的亲缘关系进行了初步研究并编制了分类检索表。结果表明:61 个油茶品种的叶片横切面均由上表皮、下表皮以及栅栏组织和海绵组织构成,叶片为异面叶,栅栏组织细胞层数多为3 ~4 层,海绵组织细胞多为椭圆形,大部分叶片组织中含有晶体和石细胞;不同品种的叶片厚度、上表皮和下表皮厚度、栅栏组织和海绵组织厚度分别为401. 13 ~ 729. 68、19. 00 ~ 36. 18、14. 05 ~ 35. 45、116. 8 ~ 271. 3 和198. 2 ~518. 4 μm,叶片组织结构疏松度和紧密度分别为38. 8% ~89. 5%和17. 2% ~44. 6%,这些指标在不同品种间均有显著差异(P<0. 05)。叶片中脉横切面由厚角组织、维管束和维管束鞘组成,维管束主要由木质部和韧皮部构成;不同品种的中脉厚度、木质部和韧皮部厚度、维管束短径分别为523. 6 ~1 317. 8、116. 1 ~364. 2、40. 0 ~181. 8和171. 8 ~529. 5μm,中脉突起度为1. 029 ~2. 041,这些指标在不同品种间均有显著差异(P<0. 05)。通过聚类分析可将供试的61 个油茶品种分为13 组,各组均具有各自的显著特征。研究结果说明:叶片横切面解剖特征可作为区分油茶品种的依据之一。

The anatomical characteristics of transection of leaf and its midrib of 61 cultivars belonging to nine lines of Camellia oleifera Abel from Zhejiang were observed by paraffin method, and on this basis, relationship among 61 cultivars was studied preliminarily by cluster analysis method and the key was also compiled. The results show that leaf transection of 61 cultivars is composed of upper and lower epidermis, palisade tissue and spongy tissue and the leaf belongs to bifacial type; cell layers of palisade tissue are most 3-4 and the cells of spongy tissue are most oval shape; and most leaf tissues contain crystal and sclereid. The thicknesses of leaf, upper and lower epidermis, palisade tissue and spongy tissue of different cultivars are 401. 13-729. 68, 19. 00-36. 18, 14. 05-35. 45, 116. 8-271. 3 and 198. 2-518. 4 μm, respectively, and loose ratio and tense ratio of leaf tissue structure are 38. 8% - 89. 5% and 17. 2% -44. 6%, respectively; and differences of these indexes among different cultivars are significant (P<0. 05). The transection of leaf midrib is composed of collenchyma, vascular bundle and vascular bundle sheath and vascular bundle mainly consists of xylem and phloem. The thicknesses of midrib, xylem and phloem, and short diameter of vascular bundle of different cultivars are 523. 6- 1 317. 8, 116. 1-364. 2, 40. 0-181. 8 and 171. 8-529. 5 μm, respectively; their midrib protuberant degree is 1. 029-2. 041; and the differences of these indexes among different cultivars are significant (P<0. 05). By means of cluster analysis, 61 cultivars of C. oleifera can be divided into 13 groups, and each group possesses itself remarkable characteristics. It is suggested that anatomical characteristics of leaf transection can be one of evidences for cultivar identification of C. oleifera.