Growth and production of Melia dubia under silvi-pasture systems and sole plantations: positive implications of intercropping hybrid napier

Abstract

Growth and yield performance of Melia dubia was evaluated under silvi-pasture systems [M. dubia- Hybrid napier (HN)] and sole plantations, to ascertain effect of intercropping HN for two years. The study was comprised of ten treatments: land uses- LU₁ to LU₅ [M. dubia (2 × 2 or 3 × 3 or 3 × 2 or 4 × 4 or 4×2 m) + HN] and LU₆ to LU₁₀ sole M. dubia with same spacing) with four replications following Randomized Block Design. Results revealed that, at planting (January, 2018) and final HN forage harvest (December, 2019), significantly (p<0.05) maximum tree height was under M. dubia (3 x 3 m)-HN system.  Initially, maximum DBH was under sole plantation spaced at 4x4 m, however, at final HN forage harvest, DBH was highest under M. dubia (4x4 m)-HN system. Maximum height (4.00 m) and DBH (8.55 cm) increment, over two years, was gained by trees in M. dubia (4 x 2 m)-HN system. At HN planting, sole M. dubia (4 x 4 m) had maximum fresh biomass (18.28 kg tree^-1) and over bark volume (0.015 m³ tree^-1), however, at final HN harvest, maximum fresh biomass (78.94 kg tree^-1), over bark volume (0.076 m³ tree^-1) and increment (62.32 kg tree^-1 and 0.063 m³ tree^-1 in biomass and volume, respectively) was of trees in M. dubia (4 x 4 m)-HN silvi-pasture system. This indicates positive implication of HN intercropping, which enhanced growth and yield of M. dubia.