Abstract
Functional food markets have increased flaxseed (Linum usitatissimum L.) demand, along with the need for competitive varieties. Flaxseed cultivated in Brazil results from natural hybridizations and mixtures of foreign genotypes. Given the unexplored genetic variability in heterogeneous Brazilian varieties, classical breeding methods like pure line selection can be effectively applied, especially when involving local producers in the breeding process. Therefore, the present study aimed to estimate the efficiency of participatory selection of superior yellow flaxseed lines from a heterogeneous variety through genetic gains obtained via the best linear unbiased predictor (BLUP). Individual plants were selected in a heterogeneous Brazilian crop in 2017, and the resulting lines were evaluated in 2018, 2019, and 2020 (across two environments). We evaluated the following traits: days to maturity (DM), number of capsules per plant (NCP), yield per area (GY), and yield per plant (GYP). Phenotypic data were used to estimate variance components via REML and genotypic values via BLUP. The efficiency of participatory plant breeding was measured by the genetic gain from selection (GS). The results reveal that the pure line selection method in a heterogeneous flaxseed variety was efficient, achieving gains of up to 5.37% for DM, 31% for NCP, 44.5% for GY, and 49.52% for GYP.