Suitability of Extractants for the Determination of Available Sulphur for Groundnut Production in Some Soils of Benue State, Nigeria

Occurrence of sulphur deficiency in Nigerian soils is becoming frequent and more extensive due to intensive cultivation and shift from low analysis to high analysis fertilizers which do not contain sulphur. Information is still required on the parameters of evaluating sulphur status and requirement of crops in the country. Studies were conducted in the laboratory, greenhouse and farmers’ fields in 2004 and 2005 to evaluate four extractants (0.16 M KH2PO4, 0.10 M Ca (HPO4)2, 0.10 M LiCl and distilled water, for the determination of available sulphur for groundnut production in some soils of Benue State. The soils include Abinsi, Adaka, Ikpayongo, Tyowanye, Yandev, Gbatse, Tse-mker and Makurdi. Fields of 8 farmers cultivating groundnut as sole crop were used to verify the findings of the laboratory and pot experiments. Among the extractants, 0.10 M LiCl related significantly with pod yield and pod number. There was also, significant relationship between the lithium chloride extractable S and the total S values of the soils.