S1 and S2 imbred progenies selection in program for intrapopulational improvement of popcorn

Abstract

One-hundred S₁ and 225 S₂ progenies obtained from the popcorn population “Beija-Flor” Zea mays L. (Poaceae), were evaluated in relation to yield, popping expansion and other agronomic characters. Genetic parameters were estimated and the predicted gains by selection were obtained according to several selection methods. Significant genotypic variability was observed for both yield and volume expansion. The direct selection for popping expansion was the method used in selecting thirty S1 progenies for intrapopulational improvement. A gain of 1.08 mL/g for volume expansion was predicted. The expected indirect gain for grain yield is irrelevant, mainly because of the negative genotypic correlation between these characters. For selection of thirty S₂ families the index of Mulamba and Mock was used, with weights 1 and 3 for yield and volume expansion, respectively. A predicted gain of 0.81 mL/g was obtained for popping expansion