Response of tepary beans to plant density in Middleveld, Swaziland

A landrace of tepary beans [Phaseolus acutifolius ] locally known as nsambasamba, literally meaning high yielding, is a relatively new crop in parts of Swaziland. The white, small-seeded [34 g/100 seeds], is popular in drought-prone areas because it is drought tolerant, early maturing, high yielding, fast cooking and palatable. However, there is scarce information on its production practices, hence this experiment. A field experiment was conducted at the Malkerns Research Station in the 2010/2011 cropping season. The treatments were four densities [50,000; 100,000; 200,000 and 400,000 plants/ha]. This was achieved by planting at 40, 20, 10, and 5 cm within rows between. The inter-row spacing [50 cm] was the same for all treatment. The design of the experiment was randomised complete block and each treatment was replicated five times. Results showed that the plant height increased with plant density. The number of pods/plant were lowest [75 pods/plant] at the highest density and highest [90 pods/plant] at the lowest plant density, thus exhibiting plant plasticity. Seed yields at the intra-row spacing of 40, 20, 10 and 5 cm were 644, 1167, 1383 and 1867 [kg/ ha], respectively. It was concluded that yield per plant decreased with increase in intra-row spacing, while yield [kg/ha] increased with reduction in intra-row spacing. It was recommended that farmers should grow tepary bean at 400,000 plants/ha using an inter-row and intra-row spacings of 50 and 5 cm, respectively.