Growth of Clones of Eucalyptus urophylla in Two Contrasting Soil Conditions in Plantations of Southeastern Mexico

Eucalyptus urophylla is important for the establishment of commercial forest plantations in Mexico. Genetic improvement programs are currently being implemented to increase timber productivity. The objectives of this study were to evaluate the adaptability and growth stability of 26 clonal lines of E. urophylla in Acrisol and Fluvisol soils and to identify the most suitable genotypes for each soil type. Tree survival, diameter at breast height, and total height were measured annually for six years. These variables were used to estimate individual volume, volume per hectare, and mean annual (MAIv) and current annual (CAIv) volume increment. Survival ranged from 14 to 100% in the Acrisol soil and from 0 to 89% in the Fluvisol soil. Volume per hectare ranged from 65.3 to 488.7 m(3), MAIv from 11.1 to 83.1 m(3) ha(-1 )year(-1), and CAIv from 2.4 to 134.7 m(3) ha-1 year-1. Individual heritability (Hi2) was moderate (0.29-0.49) while the mean heritability of the cloned lines was high (0.73-0.90), indicating that growth is subject to high genetic control. Diameter, height, and volume presented no genotype x environment interaction effects, demonstrating stability in the growth of the clonal lines in both soil types.