Variability in Yield and Yield Components of Selected Pro-vitamin A Maize (Zea mays L.) Varieties in a Humid Environment of Port Harcourt, Nigeria

This study aimed at assessing the magnitude and nature of genetic variation present in seventeen pro-vitamin A (PVA) maize varieties, investigate the extent of association among agronomic characters responsible for yield and its components in the maize varieties and evaluate the performance of the maize varieties. The field experiment was carried out at the Teaching and Research Farm of the Rivers State University, Nkpolu, Port Harcourt under rain fed conditions in May, 2018 and were laid out in a randomized complete block design with three replications. Data were collected on established plants per plot, days to 50% silking, days to 50% anthesis, anthesis-silking interval, plant height, ear height, final stand count, number of ears harvested, grain moisture content, field weight and grain yield. Results showed significant differences (P < 0.01) among varieties for all traits evaluated. PVASYN-13 had the highest grain yield per hectare among other varieties. High heritability estimates coupled with high genetic advance were observed in established plants per plot, anthesis-silking interval, final stand count, number of ears harvested, field weight and grain yield, an indication of the additive nature of their inheritance. Thus, the presence of variation could serve as basis for selection for yield improvement in maize.