Yield Performance of Extra-Early Quality Protein Maize Inbreds in Humid and Savanna Agro-environments of Nigeria

Abstract

Periodic evaluation and selection of quality protein maize inbred lines for the development of extra-early and high grain yielding maize hybrids are crucial to fostering food security in the face of climate change. This research work was conducted to assess quality protein maize (QPM) inbred lines for grain yield (GY) and other agronomic traits in humid and savanna agro-ecologies of Nigeria and the relationship among pairs of agronomic traits. Ten maize inbred lines were evaluated in three locations (Ibadan, Ile-Ife and Kishi) for two years and data were collected on GY and 12 other agronomic traits. Results obtained showed that the effects of genotypes, locations, years and their interactions were significant for most of the traits in this study at p< 0.01 across locations. Considerable variation existed among the inbred lines as reflected by coefficients of variation (CV). Highest CV (57.78%) was found for GY while the least (2.87%) was found for days to 50% silking (DS). The grain yield of the inbred lines was higher in Kishi than in Ibadan and Ile-Ife by 57.55% and 38.76%, respectively. Inbred line TZEEQI 7 had highest GY of 1512.83 kg ha-1 with good plants architecture across locations, indicating that it has favourable gene(s) to withstand weather effect than other inbred lines. Hence, it is a good inbred line for improvement for drought prone environments. It was observed that highly significant and positive relationships existed between GY and most agronomic traits. However, the trait negatively correlated with days to 50% anthesis and silking, plant aspect and ear aspect. The traits with positive and significant correlated with GY can, therefore, be used for indirect selection for yield improvement. Also, inbred TZEEQI 7 can be hybridized with normal endosperm maize genotypes for conversion to QPM for enhanced nutritional quality.