ON-FARM ASSESSMENT OF TWO LIMING MATERIALS IN CABBAGE AND HOT PEPPER CULTIVATION ON ACID SULPHATE SOIL IN GUYANA

Abstract

In researcher-designed, farmer-managed experiments with cabbage and hot pepper, ground seashells (GSS) were compared with low-grade phosphate lime (LGP) at rates of 0, 2.5, 5, 7.5 or 10 t ha⁻¹. A randomized complete block design, with replicates spread over different farms, was used. Liming with GSS or LGP at 10 t ha⁻¹ increased cabbage yield from 0.5 t ha⁻¹ without liming to 15.0 and 5.3 t ha⁻¹ respectively. Hot pepper yield was increased from 2.1 t ha⁻¹ without liming to 3.2 t ha⁻¹ at the three highest rates of GSS and LGP. Application of GSS increased the pH, reduced exchangeable acidity and increased the extractable Ca content of the soil. Partial budget analyses revealed that cabbage and pepper growers obtained highest returns with GSS at 10 and 5 t ha⁻¹ respectively.