Ganho genético em aveia branca, trigo e girassol no Rio Grande do Sul

Abstract

The objectives of this study were to evaluate the genetic progress of oat (Avena sativa L.), wheat (Triticum aestivum L.), and sunflower (Helianthus annuus L.) in trials organized and performed by the yield trials network of oat, wheat, and sunflower in the state of Rio Grande do Sul (RS), to evaluate the genetic progress in trials performed with and without fungicide use in oat for grain yield and hectoliter weight; to study the genetic progress in trials performed in homogeneous growing regions of wheat for grain yield; and to study the genetic progress in sunflower for grain yield, oil content, and oil yield. For oat, 89 trials belonging to the yield trials network were used with trials divided into with and without fungicide use and the trials were performed in nine municipalities in the RS during the period of 2007 to 2014. For wheat, 137 cultivar trials belonging to the state wheat cultivars trials (EECT) were used, with trials divided into two homogeneous growing regions. Trials were performed in 23 municipalities in the RS during the period of 2002 to 2013. For sunflower, 58 cultivars trials belonging to the sunflower genotypes assessment trials network were used and the trials were performed in 19 municipalities in the RS during the period of 2005 to 2014. The methodology proposed by Vencovsky et al. (1988) was utilized for the study of genetic progress and the balance of genetic progress was determined by the method of generalized least squares. The annual genetic progress for oat grain yield was 1.02% with fungicide use and 4.02% without fungicide use during the period of eight years in RS. Regarding the hectoliter weight, the annual genetic progress was 0.08% for trials with fungicide use and 0.71% for trials without fungicide use. Performing network yield trials with and without fungicide use in the aerial part is feasible to evaluate the efficiency of oat breeding programs in the introduction of disease resistance genes in released cultivars. Annual genetic progress for wheat grain yield during the period of 12 years in the state of RS was 2.86%, oscillating between homogeneous growing regions. The difference of annual genetic progress in region 1 (1.82%) in relation to region 2 (4.38%) justifies the study of genetic progress by homogeneous growing regions. Annual genetic progress of sunflower during the period of ten years (2005-2014) for grain yield was 8.58%, for oil content was -0.38%, and for oil yield was 7.13%. The sunflower breeding programs in the state of Rio Grande do Sul were efficient for the traits grain yield and oil yield and presented no efficiency for oil content.