Selection among endogamic S1 progenies for corn ear worm resistance in two opaque-2 maize populations

Abstract

One cycle of selection, based on evaluation of S₁ progenies in two opaque-2 maize populations: ESALQ-VD opaque and Piranão-VD opaque for corn earworm resistance was made during 1985/88 in Jaboticabal, SP, Brazil. The resistance was evaluated under natural infestations for low H. zea ear dammage (DHZ), good husk compaction (CoP) and longer husk extension (EP) beyond ear tip. The best 28 progenies were selected in each populations for later recombination. The estimates of average expected gain obtained were: 19.9% (CoP), 6.5% EP and 55.8% (DHZ) in Piranão-VD opaque; in ESALQ-VD opaque these values were 34.0% (CoP), 15.9% (EP) and 0 (DHZ). It was concluded that selection of resistant genotypes in both populations, and that the selections method based on S₁ progenies is potentialy useful in breeding for these characteristic.