Preliminary Seedling Quality Grading of Dendrocalamus yunnanicus
Cheng Lin, Li Lijie, Chen Shichang, Huang Dayong
Guangxi Forestry Research Institute, National Forestry and Grassland Administration Key Laboratory on Cultivation of Fast-Growing Timber in Central South China/Guangxi Key Laboratory of Superior Timber Trees Resource Cultivation, Nanning 530002, China
Abstract：In order to evaluate the quality of Dendrocalamus yunnanicus seedling, the 0.5-year-old seedlings were selected for determining the quality grade by using the K-means clustering method and standard deviation method, and the ground diameter (D), seedling height (H) and number of seedlings per cluster (N) are used as the seedling quality grading indexes. The results show that there is a significant positive correlation between seedling height, ground diameter and other growth indexes(P<0.01). It is feasible to use seedling height, ground diameter and number of seedlings per cluster as the basis for seedling quality grading. Through comprehensive evaluation, the quality grading standard of 0.5-year-old seedlings of D. yunnanicus is determined as follows: H≥37 cm, D≥3 mm and N≥4 for Grade I; 27≤H＜37 cm, 2≤D＜3 mm and 3≤N＜4 for Grade II; 16≤H＜27cm, 1≤D＜2 mm and 2≤N＜3 for Grade III. The results provide science basis for the further classification of seedling grades and the selection of improved varieties of D. yunnanicus.