Effect of Exogenous Hormone and Media Type on Quality of Ex Vitro Rooting Subculture Plantlet of Cunninghamia lanceolata

The trial was designed by orthogonal design and simplex centroid mixture to find out the effects of different exogenous hormone and media on quality of Cunninghamia lanceolate clones. The results showed that the concentration of exogenous hormone had a great influence on the ex vitro rooting rate and root number of subculture plantlet buds of C. lanceolate clones. The combination of soaking buds in 100 mg/L IBA solution for 1 hour was the best solution, with an average ex vitro rooting rate of 89.56%. The composition and proportion of media had significant effects on ex vitro rooting rate and quality. Peat soil and vermiculite should be the main components of transplanting media. On the contrary, pearlite and red mud should not be added or added as little as possible. Root morphological parameters, including total root length, total root surface area, total root volume and average root diameter, are important indices for evaluating the quality of ex vitro rooting subculture plantlet of C. lanceolate. The quality of C. lanceolate clone was comprehensively evaluated by subordinate function values, and the ex vitro rooting rate was also taken as the important index. And then, No. 7 media, contained 60% peat soil and 40% vermiculite, was selected as the best media. Cultivated in No. 7 media for 2 months, the ex vitro rooting rate was 79.91%. After 12 months of cultivation, average height and ground diameter was 23.80 cm and 4.09 mm, respectively. And root architecture and comprehensive quality of C. lanceolate clones were better than that cultivated in red mud.