Intra-and intergenotypic competition among commercial eucalyptus clones

Abstract

Plantations made up of clones carry genetic uniformity that can compromise production. The use of multiclonal plantations is a possible solution. The objective of this study was to identify effects of competition on silvicultural performance of Eucalyptus spp. commercial clones. The experiment was carried out in a randomized block design with 12 eucalyptus clones, three replicates, and five plants per plot. Clones were evaluated for two competition types, intra-and intergenotypic, at 3 and 5 years of age. Competition parameters were estimated based on the analyses performed. Differences were found between the types of competition at both ages for mean annual increment and wood volume. Clones 8 and 9 stood out from the others in both intra-and intergenotypic competition. At 5 years of age, intergenotypic competition produced productivity gains of 13% in clones 8 and 9 and 4% overall considering wood volume and mean annual increment.

Complementarity increases production in genetic mixture of loblolly pine (Pinus taeda L.) throughout planted range

“…In Eucalyptus spp. plantations, mixing genotypes has resulted in mean annual increment gains of 7.7% (Rezende et al 2019) and 4% to 13% (Pavan et al 2019). Rarely, however, are these studies long-term (i.e., >7 yr), tested at operational scales or conducted with loblolly pine.…”

“…Robinia spp., Paulownia spp., and Salix spp. (e.g., DeBell and Harrington 1997, Brodie and DeBell 2004, Boyden et al 2008, Hoeber et al 2018, Pavan et al 2019, Rezende et al 2019, Schweier et al 2019), as well as for Pinus elliottii and loblolly pine (Adams et al 1973, Staudhammer et al 2009). These studies have yielded mixed results as productivity responses often depend on site, spacing, silvicultural inputs, and genotypic combination.…”