Evaluation of wood characteristics in the first selection phase of a willow (Salix spp) breeding program in Argentina

CERRRILO TERESA; MONTEOLIVA SILVIA

Conferencia; IUFRO All Division 5 Conference 2012; 2012

Willow wood is suitable for a broader range of forest products, including furniture components and veneer for plywood. In Argentina willows are used in the pulp and paper industry and for production of particleboard and, secondarily, for saw-timber. In order to improve the quality of the willow plantations INTA is developing a breeding program that has reached different phases of selection, with over 3000 genotypes. Selection criteria include fast growth, resistance diseases, stem form and wood quality.   This paper reports results of the first selection of new 1800 genotypes of seven families of Salix alba L., S. amygdaloides Anderss., S. babylonica L., S. matsudana  Koidtz and S. nigra Marsh, that were obtained by inter- and intra-specific hybridisation in 2008. Six of them were originated by means controlled crossings (CC) in greenhouse and the other one, by open pollination (OP). All genotypes obtained were put in forest plant pots until the age of 10 months; after that, progenies were planted at field. A completely randomized design is utilized, with 10 genotypes/plot/family. At 34 months all survived plants (1674) have measured (height and diameter); and diseases and stem form have registered. Studies on wood density and characteristics of fibers were carried out.   ANOVA showed that height growth differed significantly between families and genotypes within families. The highest were family 09 (OP of an individual originated in the cross S. matsudana x S. nigra), 7.20 m (±1.24 m) and family 05 (S. amygdaloides x S. alba), 6.35 m (±1.25 m). The family was a significant source of variation for basic density and fiber length. Families that include S. matsudana(01, 07 and 09) hadthe longest fibers(836-864-812 um respectively) and high densities (0.403-0.397g.cm-3, 01 and 07 respectively).The family 09 despite being a cross x S.matsudana had lower density (0.350 g.cm-3). The families 05 and 09 showed the best diameter growth(6 cm) but had low densities (0.350 g.cm-3). As result of this first selection (screening), 200 genotypes or experimental clones were selected.