Bean growth and yield response to irrigation, nitrogen fertilizer and planting density under temperate and tropical conditions

AbstractBeans (Phaseolus vulgaris var Mwezi Moja) were grown in the field under two irrigation levels (irrigated and rainfed), two nitrogen levels (no fertiliser and 100 kg N ha−1) and two planting densities (22 and 44 plants m−2) at Sonning (UK) and Kabete (Kenya). The crop duration in the three experiments was 114 days in Sonning, 95 days in K1 and 73 days in K2. Irrigation increased total dry matter early in the season at Sonning but had no effect at Kabete experiments because of high rainfall in K1 and ‘ineffective’ irrigation in the drier K2 where most of the water was lost through evaporation.Total above ground dry matter (TDM) production at Sonning was higher than at Kabete in the wet season (K1 experiment) despite very similar weather conditions. Total dry matter and seed yields were lowest in the dry season Kabete experiment (K2). Nitrogen increased TDM at Sonning and K1 experiments but not in K2. High planting density increased TDM in all the experiments, and bean planting density response was m...