Study on the Growth and Phenological Characteristics of Populus deltoides Germplasms

The gene bank constructed from Populus deltoides, provides technical support for resource evaluation and exploitation. The phenological, growth and gender characteristics of 7 years old P. deltoides in this gene bank were analyzed. The results showed that the phenology and growth characteristics of different clones were rich. The results of correlation analysis between growth and phenological characters indicated that the leaves fell late, which was beneficial to the growth of tree height and DBH. The excellent proportion and breeding potential of male plant were more advantageous, appropriate attention should be paid to the selection of male plant in the future. Combination with volume, DBH, phenological growing season and other traits, 41 excellent clones were selected from 443 germplasm. The statistical results of selected clones showed that the female parent of 25 clones were from Mississippi River basin, accounting for about 60.98%. Especially the female parent of the 5 clones with the largest volume come from the superior plant of the natural forests in the lower reaches of the Mississippi River. On the whole, the gene bank was rich in genetic diversity, the characteristics of growth and phenology were different among the clones, and 322, 331-9, 329-26, 1-31 performed well, which had good breeding potential.