Multi-level Genetic Variation in Leaf and Growth of Hybrid System between Populus deltoides and P. cathayana

The controlled hybridization between a female Populus deltoides Marsh,'55/65' and 5 provenance (10 individuals each provenance) of the male P. cathayana Rehd. produced the hybridization system with multi level variations for breeding. The 7 leaf traits, including leaf length, leaf width, ratio of leaf length to width, petiole length, ratio of petiole length to main vein, angle between main and the second leaf vein, leaf base of the parents and F 1 hybrid were analysized. The analysis of variance showed that significant difference of leaf traits existed among provenances and among individuals within provenances of P. cathayana. Several leaf traits of F 1 hybrid also showed significant difference among provenances, among families within provenances and among clones within families. Comparison between leaf traits of parent and those of F 1 hybrid suggested that the male parent has more effects on leaf traits of F 1 hybrid than of female parent. No significant difference of plant surviving existed among F 1 clones. The significant difference of 1,2,3 year old growth among F 1 clones showed that the variation of male parents brought notable effect on growth of F 1 clones. Correlation between leaf and growth of F 1 clones was not significant. These results of analysis will provide more base information about multiple level variations on such traits as growth and wood properties for poplar breeding in future.