Comparison on microscopic structures of vegetative organs of nurse seed grafted and cutting Camellia oleifera
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 class Ⅰ;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.
万方数据
维普
