Seleção simultânea de caracteres em progênies de Pinus caribaea Morelet var. bahamensis

Abstract

In order to obtain superior materials, the selected genotype needs to simultaneously have a group of favorable attributes and give a higher yield, so as to satisfy both the consumer and the producer. The objective of this work was to determinate the gain expected trough direct selection in each trait studied (height, breast-high diameter, stem form and volume), as well as through simultaneous selection based on the classic selection index (Smith and Hazel) and trough rank addictions in progenies of Pinus caribaea var. bahamensis. The 119 progenies were supplied by the Institute de Pesquisas e Estudos Florestais - IPEF-ESALQ/USP (ESALQ/USP Forest Study and Research Institute) in Piracicaba city, São Paulo State, Brazil, originated from the Centro de Conservação Genética e Melhoramento de Pinheiros Tropicais - CCGMPT (Tropical Pines Improvement and Genetic Conservation Center), in the city of Aracruz, ES, Brazil. The experiment was established in March 1990 at the school and research farm of Ilha Solteira's engineering faculty in the city of Selviria, MS, Brazil, and was evaluated when it was 13 years old. Significant differences were detected (P<0.01) among progenies in relation to the four traits studied. Selection indexes were shown to be adequate for the selection of the evaluated traits and, when compared to the direct selection, they distributed the obtained gains in a more equilibrated manner, and so favored superior progenies selection, which in turn propitiated the conditions necessary to turn the progenies test in a seedling seed orchard and to supply material to establish a clonal seed orchard.