Seleção genômica em arroz irrigado para tolerância ao frio no Sul do Brasil

Abstract

Rice is a crop of great social and economic importance and low temperatures in crop development can be extremely harmful, especially in the reproductive period causing increased spikelet sterility and consequent reduction in grain yield. This work aimed to estimate the prediction of genetic values for phenotypic and genotypic data of an F6 population of Recombinant Inbreed Lines (RILs) from a cross between the cold sensitive cultivar, BRS Atalanta and the cold tolerant cultivar, Nipponbare, to verify the genomic selection efficiency from population and markers for cold tolerance in southern Brazil. Population was phenotyped for traits: plant height, panicle length, number of spikelets per panicle, percentage of spikelet sterility, degree of panicle exertion and number of days to 50% flowering. Variances and genetic parameters were estimated to obtain the predicted genetic values for all traits in all families of the population. Means analysis and family grouping were performed, making it possible to highlight the presence of genetic variability for the studied traits, by the formation of distinct groups between families and consequently, for cold tolerance. Genotyping by sequencing of 195 families and BRS Atalanta and Nipponbare cultivars was performed and 27430 SNPs markers were identified in the population. Accuracies obtained through the marker-based predicted genetic values confirm the efficiency to use this population and markers for genomic selection for cold tolerance (accuracy of 0.80 for predicted genetic values for spikelet sterility percentage).