Varietal Response to Double Plant Population Density in Maize: Implications for Breeding

Abstract

Purpose : Suboptimal plant population has been identified as one of the causes of low yield of maize in Nigeria, hence the need for increased plant population per hectare. Maize varieties respond differently to increased plant population density. There is need to identify maize varieties that respond well to increased plant population density towards developing maize for tolerance to population stress. Research Method : Four new maize varieties were tested under population density of 53,333 (ND) and 106,666 plants/ha (DD). The trials were conducted at two locations in two seasons. The experimental design was split plot in three replications. The DD plots received additional 50% of fertilizer. Data were collected on agronomic and yield traits. Findings : Mean squares due to density were significant for grain yield and the number of ears per plant. Mean squares due to variety was significant for all traits except the number of ears per plant. Yield and plant appeal under DD were generally lower than under ND except in few instances. For instance, grain yield under DD was higher (4.96tons/ha) than under ND (4.61tons/ha) for BR9943DMRSR at Ile-Ife, and for BR9928DMRSR (2.47tons/ha under DD, 2.09tons/ha under ND) at Ilora. Only BR9928DMRSR had an increased grain yield from ND (2.41tons/ha) to DD (2.48tons/ha) across locations. Originality / Value : The variety, BR9928DMRSR, with increased yield and reduced plant height from ND to DD seemed promising for improvement for tolerance to plant population stress.