以油茶（Camellia oleifera Abel）品种‘长林40号’（‘Changlin 40’）为研究对象，通过微波快速石蜡切片法，比较芽苗砧嫁接和扦插油茶营养器官（根、茎、叶）显微结构的变化规律，解析不同繁殖方式油茶愈伤组织形成和根系发育过程，揭示植株宏观生长与微观结构间的内部联系，分析根、茎、叶显微结构指标间的相关性。结果显示：芽苗砧嫁接和扦插油茶的愈伤组织形成及愈合期分别为0~40和0~20 d。扦插20 d，油茶插穗基部皮层诱导产生根原基细胞；扦插90 d侧根开始形成。芽苗砧嫁接40 d，油茶砧木和接穗愈伤组织完全连接；芽苗砧嫁接90 d，主根增粗，大量侧根产生。芽苗砧嫁接2年生油茶茎木质部增厚，茎木质部率约为扦插油茶的2倍；叶主脉木质部厚度（334.41 μm）显著高于扦插油茶（249.70 μm），木质化程度明显增大。相关性分析结果显示：芽苗砧嫁接油茶大多数显微结构指标间存在显著或极显著相关性。芽苗砧嫁接油茶19个显微结构指标在平方欧氏距离4.0处分为4类，其中，根维管柱厚度、叶片厚度、茎髓部厚度和根中柱鞘厚度4个指标聚为Ⅱ类，茎木质部厚度（Ⅲ类）和茎直径（Ⅳ类）单独聚类，其余13个指标聚为Ⅰ类；根维管柱厚度、茎木质部厚度和叶主脉厚度分别为根、茎、叶的代表性指标，相关指数分别为0.897、0.882和0.650。综合结果显示：芽苗砧嫁接油茶的生根情况较好，根维管柱增粗，茎和叶木质部分化能力强，叶主脉增厚，组织结构紧密度增加，芽苗砧嫁接可作为油茶品种‘长林40号’低产林改造的繁殖方式；根维管柱厚度、茎木质部厚度和叶主脉厚度可作为评价芽苗砧嫁接油茶发育特性的典型指标。

 Taking cultivar ‘Changlin 40’ of Camellia oleifera Abel as the research subject and using a microwave rapid paraffin section method, the variation patterns of microscopic structures of vegetative organs (root, stem, and leaf) of nurse seed grafted and cutting C. oleifera were compared, the processes of callus formation and root system development of C. oleifera under different propagation methods were elucidated, the internal relationships between macroscopic growth and microscopic structures of plant were revealed, and the correlations between microscopic structure indexes of root, stem, and leaf were analyzed. The results show that the callus formation and healing period of nurse seed grafted and cutting C. oleifera are 0-40 and 0-20 d respectively. After 20 d of cutting, root primordium cell is  induced in the basal cortex of C. oleifera cuttings; after 90 d of cutting, lateral root begins to form. After 40 d of nurse seed grafting, the callus of rootstock and scion of C. oleifera are completely connected; after 90 d of nurse seed grafting, the taproot thickens and a large number of lateral roots are produced. The stem xylem of the nurse seed grafted twoyearold C. oleifera become thicker, and the stem xylem rate is approximately twice that of cutting C. oleifera; the main vein xylem thickness of leaf (334.41 μm) is significantly higher than that of cutting C. oleifera （249.70 μm）, indicating a notable increase in lignification. The correlation analysis result shows that there are significant or extremely significant correlations between most of the microscopic structure indexes of nurse seed grafted C. oleifera; the 19 microscopic structure indexes of nurse seed grafted C. oleifera can be divided into four categories at square Euclidean distance of 4.0, among them, the four indexes of vascular cylinder thickness of root, leaf thickness, stem pith thickness and root pericycle thickness are clustered into class Ⅱ, stem xylem thickness (class Ⅲ) and stem diameter (class Ⅳ) are clustered separately, and the other 13 indexes were clustered into classⅠ; vascular cylinder thickness of root, stem xylem thickness, and main vein thickness of leaf are representative indexes of root, stem and leaf respectively, and the correlation indexes are 0.897, 0.882 and 0.650 respectively. It is suggested that the rooting condition of nurse seed grafted C. oleifera is relatively good, with thickened root vascular cylinder, strong differentiation ability of stem and leaf xylem, thickened leaf main vein, and increased tissue structure tightness, and nurse seed grafting can be used as a  propagation method for  lowyielding forest improvement of cultivar ‘Changlin 40’ of C. oleifera; the vascular cylinder thickness of root, stem xylem thickness, and main vein thickness of leaf can be used as typical indexes to evaluate the developmental characteristics of nurse seed grafted C. oleifera.