Intrapopulation recurrent selection targeting early flowering and grain yield in upland rice
Laís Moretti Tomé, Yasmin Vasques Berchembrock, Amanda Mendes de Moura, Gleice Aparecida da Silva Lima, José Manoel Colombari-Filho and Flavia Barbosa Silva Botelho
Abstract: The selection of parent lines is critical to the success of a recurrent selection program. To establish a base population optimized for early flowering and high grain yield in upland rice, a partial diallel cross was performed using five early-flowering and four high-yielding parental lines, generating 19 subpopulations. In the field, the 15 earliest-flowering plants from each F2 subpopulation were selected to develop F2:4 progenies. 152 F2:4 progenies, comprising eight progenies per subpopulation and four control lines, were evaluated using a triple alpha-lattice design (12×13). The traits assessed were days to flowering and grain yield. The lines BRSMG Caçula, BRSMG Relâmpago, and BRSMG Caravera demonstrated strong general combining ability for early flowering. Furthermore, progenies with shorter growth cycle and high grain yield were identified, supported by a negative correlation between these traits. Superior progenies are crossed to form Cycle 1 of the recurrent selection program based on these results.