Abstract
The effect of plant spacing on growth and yield of winged bean (Psophocarpus tetragonolobus (L.) D.C.) cultivar Chimbu was evaluated at Guam Agricultural Experiment Station. Plant spacings included 12.5, 25.0, 50.0 and 75.0 cm within-row at the same between-row spacing of 1.22 m (equivalent to 13,333, 20,000, 40,000 and 80,000 plants/ha, respectively). Days to first flower in closest spacing (12.5 cm) was significantly delayed 8 days longer than that from widest spacing (75 cm). Wider spacings of 50 and 75 cm produced higher numbers of basal branches (3.6 and 3.8, respectively) and green pods per plant (65.3 and 83.3, respectively) than closer spacings of 12.5 and 25 cm. For yields both of green pod and dry seed the optimum spacings were plant spacings of 50 and 75 cm. The result of higher yields indicated that cultivar Chimbu compensated for wider spacings by producing higher numbers of basal branches and green pods and larger green pods than at closer spacings.