Effect of Plant Population on Yield of Selected Maize (Zea mays L.) Varieties in Mwea and Bura in Kenya

The objective of the study was to determine the effect of plant population on the growth and yield of maize. The study was conducted during the short rainy season of December 2018 and April 2019 in Mwea, Kirinyaga County and Bura, Tana River County, in Kenya. An experiment was set in a split-split plot design with three replications. Five selected maize (Zea mays) varieties commonly grown in these areas namely: Pioneer, DH04, Sungura, SC Duma and DH02 were grown under three plant population densities namely: 53,333, 66,666 and 88,888 plants ha-1 under irrigated conditions. Cob length, ear height, plant height, above ground biomass and grain yield data was collected. Plant population had significant effects on the grain yield and yield components of the selected maize varieties. The plant population of 53,333 plants ha-1 gave significantly higher above ground biomass in Mwea than population of 88,888 plants ha-1, though not significantly different from population of 66,666 plants ha-1. In Bura, the plant population of 88,888 plants ha-1 gave significantly higher above ground biomass than that of 66,666 and 53,333 plants ha-1 respectively. An increase in plant population reduced the grain yield of the selected maize varieties but increased the above ground biomass of the varieties.