The paper, Evaluation of plant population densities for hot pepper in Trinidad and Tobago by Herman Adams, F. Bruce Lauckner and Gaius Eudoxie is featured in the CARDI Review issue 14: pp.5-12
Research results from the neotropics showed a high positive correlation between plant population densities and yields of marketable berries in hot pepper (Capsicum chinense Jacq.). Densities were compared on a Piarco Series soil (Ultisols of the Aquoxic Tropudults sub-group) during 2011 in central Trinidad on cv. Moruga Red to determine the density that will produce the highest yields of berries, mean berry weights and mean plant developmental traits. The 16 different densities ranged from 60 x 30 cm to 150 x 120 cm.
The split-plot design comprised four levels of between-row spacings of 60, 90, 120, and 150 cm. The sub-plots represented four levels of within-row spacings, viz.: 30, 60, 90, and 120 cm. The 16 treatments were replicated thrice thus producing 48 gross plots of 6 x 6 m each. The nett plots in the centre of the gross plots measured 4.88 x 4.57 m (22 m2). A principal finding was that the highest plant population densities, 60 x 30 cm, 90 x 30 cm, 120 x 30 cm and 150 x 30 cm yielded the highest weight of berries per nett plot (P = 0.001). Another conclusion was that the different densities had no effect on mean weights of the berries (P = 0.080), mean plant height (P = 0.702), mean width of plant canopy (P = 0.46) and mean number of secondary lateral branches per plant (P = 0.655). The results from this study should guide farmers to adopt higher plant population densities.