Effects of spatial arrangement and population density on the growth and yield of sesame (Sesamum indicum L.) in a sesame/maize intercrop

A field experiment was carried out at the Teaching and Research Farm, Kwara State University, Malete, Nigeria. The aim of the experiment was to investigate the growth and yield of sesame (Sesamum indicum L.) as affected by the row arrangement and population density of maize (Zea mays L.). The full population of sesame in two-row arrangements (1:1) and (2:2) was combined with four population densities of maize viz: 100S:100M; 100S:75M; 100S:50M and 100S:25M (where S and M represented sesame and maize, respectively). Sole crops of sesame and maize at full population were included in the treatments as control. The number of pods per plant (NPP), length of fruit zone (LFZ), and yield of sesame were significantly (P?0.5) influenced by the interactive effect of population ratios and row arrangements. These variables increased as the population of associated maize decreased. All variables measured in maize were influenced by population density and row arrangement except for the number of cobs per plant (NCP), cob length (CL), and cob circumference (CC). Regardless of spatial arrangement and population density, the aggressivity (A) value was positive for sesame and negative for maize. The competitive ratio (CR) values were also higher in sesame than in maize. Land equivalent ratio (LER) and land equivalent coefficient (LEC) values, for all population ratios tested, indicated the intercropping advantage with the highest value recorded at a full population of sesame mixed with fifty percent population of maize in a 2:2-row arrangement and hence, recommended for adoption.