Grain yield and yield components of three maize cultivars in two planting dates

Abstract

A field experiment was conducted to study the effects of two planting dates (October 10, 1984 and November 1st, 1985) on potential and final yields and their yield components of three corn (Zea mays L.) cultivars. The three cultivars Agroceres 28C, Cargill 408 and Pioneer 6872 were planted at the Agronomy Experimental Station of the UFRGS, located in Guaíba, RS, Brazil. The average grain yield was reduced 9,0 per cent, from the first to the second planting date for all cultivars. As planting was delayed, row of ovules per ear, number of ovules per ear and kernel weight (except for Pioneer 6872 cultivar) decreased. Ovules per row, ear per plant, kernel per row and kernel per ear were not changed. As a result of a higher number of rows per ear and a greater number of kernels per ear, Pioneer 6872 cultivar presented the highest grain yield.