Decomposition dynamics and nutrient release by pigeon pea genotypes under alley cropping

Abstract

The objective of this research was to evaluate the aerial biomass, N, P and K contents, and the dynamics of decomposition and mineralization, in six genotypes of pigeon pea, grown as hedgerows in an alley cropping system. Dry biomass production averaged 5.9 Mg ha^-1; N content ranged from 188.3 to 261.3 kg ha^-1; P content, from 7.2 to 9.4 kg ha^-1 and K content, from 29.3 to 45.5 kg ha^-1. No differences between genotypes were found. Decay curves indicated a rate of 75% of the biomass still remaining 30 days after deposition. Also, approximately 60% of N, and 65% of P and K, of the remaining biomass, were released to soil. No effects of pigeon pea genotypes were found in decomposition or mineralization rates.