Effects Of Matrix And Illumination Intensity On Seedling Growth Of Acer Cordatum ’Huoyan’

Acer cordatum ‘Huoyan’ is an evergreen tree of the genus Eucalyptus.It is an excellent landscaping tree species whose leaves combine ornamental value.The study of growth rhythm,optimum substrate for raising seedlings and the optimum light intensity can provide a theoretical basis for the large-scale production of A.cordatum ‘Huoyan’ and the establishment of the seedling management system.The findings are as follows:(1)The growth rhythm showed a “S” type curve,the determination coefficient varied of seedling height and stem diameter was 0.979,0.983;and seedling growth had obvious stage,seedling height growth peak appeared 2 times,stem diameter peak appeared3 times,and the seedling growth of A.cordatum ‘Huoyan’ could be divided into 3 stages in general,the early stage was before mid july in height and before late june in diameter,the fast growth stage was form mid july to mid september in height and from early july to late september,the late growth stage was after mid september in height and after late september in diameter.Than the managements for various stages were given out.(2)Different matrix components and ratios have a significant effect on the seedling height,diameter increment,and biomass accumulation above and below ground in annual seedlings of A.cordatum ’Huoyan’.Mixed substrates are more conducive to the growth of seedlings than single substrates,Appropriate amount of yellow soil and peat are conducive to promoting the growth of seedlings,and the optimal matrix ratio is obtained through the quadratic polynomial stepwise regression equation analysis: Yellow soil: peat: fungus residue: alfalfa ash = 0.378:0.285:0.189:0.149.(3)Shading has extremely significant effects on seedling height,ground diameter and biomass.With decreasing light transmittance,seedling height,ground diameter gradually decreases,and height-to-diameter ratio gradually increases,but severe shading(15 % light transmittance)will reduce the ratio of seedling height-to-diameter;shading will also affect the distribution of roots,stems and leaves of seedlings.With the decrease of light transmittance,the proportion of root and stem will gradually decrease,the proportion of leaves will gradually increase,and the root to shoot ratio and the seedling quality index gradually decreased.Therefore,the young seedlings of flaming violet pods belong to the hi-positive tree species and should ensure sufficient light during the seedling stage.