Interactions between environment and traits and analysis of stability in new triploid clones of Populus tomentosa

ObjectiveBetter understand genetic variations, clone × interaction and stability for growth traits and wood properties of pulpwood in new triploid clones of Populus tomentosa  can provide specific information for  developing new varieties in planting area.

MethodGrowth traits and wood basic density of 7-year-old pulpwood of new triploid clones of P. tomentosa at five clonal trials located at Shanxi Province, Shandong Province and Henan Province were investigated. Then, genetic variations and stability parameters were also estimated.

ResultThe results indicated that the site and clonal effects were highly significant for the growth traits, wood basic density and trunk dry mass. Site × clone interactions were also highly significant for growth traits and trunk dry mass. However, it did not have significant effect on wood basic density. Clonal repeatability of wood basic density in triploid clones of P. tomentosa was 0.92, slightly higher than DBH (0.90), tree height (0.84), individual volume (0.86) and trunk dry mass (0.80). Triploid clone B303 with high yield and higher stability and two triploid clones B331, B302 with higher wood basic density and stability were developed. The results of stability evaluation in growth traits were not consistent with the results in wood basic density owing to the negative correlations between the growth traits and wood basic density. It is suggested that trunk dry mass is considered as a reasonable index to develop new pulpwood varieties.

ConclusionOur findings strengthen recognition of wood properties and its factors, and provide technique reference for developing new pulpwood varieties. It also plays an important role in guiding the popularization of new varieties.