Evaluation of populations of Irrigated Rice Conducted by Recurrent Selection in lowland in Roraima. = Avaliação de populações de arroz irrigado conduzidas por seleção recorrente em várzea de Roraima.

Abstract

The objective of this study was to evaluate irrigated rice populations conducted by recurrent selection to identify those with greater potential for use in new cycles of recurrent selection, as well as materials to be used as inbred lines, seeking to release systems as new cultivars of rice production in lowland of Roraima. For that were evaluated during the period December 2008 to April 2009, hundred rice genotypes derived from recurrent selection populations. Experiment was Federer’s augmented blocks with plots of four rows with five meters in length and floor area of two central lines. Analysis of variance were performed for all individual characteristics, and obtained estimates of heritability (h2), genetic variation coeficient (CVg), and genotypic and phenotypic variances. It was further estimated the genetic gain expected from selection (GS) of the families more productive than the average for all families using a selection intensity of 35%. It was concluded that the population CNA 12/1/1 shows promise for use in recurrent selection programs to extract the lines of irrigated rice in Roraima.

Keywords

• Oryza sativa
• Breeding population
• Genetic gain.