Analysis of testers with broad and narrow genetic base for topcrosses in popcorn breeding
RJB Pinto, CA Scapim, A Ferreira Neto, CAP Pacheco, M Royer, MV Pedroni, RK Salvadori and RM Silva
Abstract: Three testers (three-way hybrid Zélia, single-cross hybrid IAC 112 and composite CMS 43) were compared in the evaluation of the combining ability of 36 popcorn S> families obtained from CMS 43. The performance per se of the families was evaluated in a randomized complete block and in 6 x 6 lattice design when in crossings with testers. Estimates of genetic parameters for grain yield and popping expansion were compared among the two sets of progenies (S2 families per se and topcrosses). The general and specific combining abilities were estimated following Griffing’s partial diallel model. The heterosis of each topcross was evaluated in relation to the performance per se of testers. The discrimination ability of testers was compared through the differentiation and performance index. Correlation estimates were obtained among four sets of means: the S> families and the three topcross sets. Results showed that Zélia was the most appropriate tester for both evaluated traits.