Cowpea Yield Performance in an Alley Cropping Practice on an Acid Infertile Soil at Ebini, Guyana

Patrick E.K Chesney,R Nigel Cumberbatch,Oudho Homenauth,Leslie A Simpson,Floyd Benjamin

doi:10.2174/1874331501004010080

Abstract

The yield performance of cowpea var. Minica # 4 (Vigna unguiculata L.) on an Arenic Paleudult (Acrisol) was evaluated in an alley cropping experiment with Gliricidia sepium (Jacq.) Kunth ex Walp., Leucaena leucocephala (Lam.) de Wit and a treeless control during a short- (November-December 2004), and long-(May-June 2005) rainy season at Ebini, Guyana. The alley cropping treatments had no significant effect on cowpea plant height, pods per plant, pod weight per plant and grain weight. During the short-rainy season, values for cowpea plant height and number of pods per plant were higher compared to those for the long-rainy season, and number of pods per plant was positively correlated with pod weight. During the long-rainy season, pod weight and grain weight were correspondingly higher. Plant height vs. number of pods per plant; number of pods per plant vs. pod weight; and, number of pods per plant vs. grain weight, were all positively correlated. Cowpea could yield the same or more when associated with managed fast growing, nitrogen (N)-fixing trees or treeless plots. This alley cropping practice has the potential to reduce the use of fossil-fuel generated fertilizers and reduce the potential production of an important greenhouse gas (GHG).

Highlights

The Intermediate Savannas (50 30” N, 580 00” W) of Guyana are located approximately 160 km south of the Atlantic Ocean behind the low-lying coastal plains
The present study investigated the performance of cowpea in an alley cropping system with G. sepium, L. leucocephala and no-tree control on an acidic infertile Arenic Paleudult at Ebini, Guyana, to test the hypothesis that the introduction and management of fast growing, N2-fixing trees on smallholder farms provide an opportunity to reduce requirement for costly soil and crop inputs without concomitant loss in crop yield
The experimental plots were established in March 1997 to evaluate the performance of cereal (Z. mays) and grain legume (V. unguiculata) crops in alley cropping trials with L. leucocephala and G. sepium and treeless control treatments

Summary

Introduction

The Intermediate Savannas (50 30” N, 580 00” W) of Guyana are located approximately 160 km south of the Atlantic Ocean behind the low-lying coastal plains. Soils of agricultural importance are loamy, siliceous, isohyperthermic, very acid, highly leached, and excessively permeable, of low natural fertility and exchange capacity [2]. Current efforts to develop the Intermediate Savannas for agricultural land-use are based on the perceived threat to the fertile, low-lying and populous coastal belt from sea level rise and increasing urbanization, and the need for alternative lands for commercial agriculture. Three decades of soil and crop research in the Intermediate Savannas have led to the development of cereal and grain legume crop rotation models. Achieving economic crop yield on the soils of the Intermediate Savannas requires soil tillage, annual soil pH amelioration, fertilizers, and large scale cropping. The cost of these inputs is prohibitive

Methods

Results

Conclusion