SOIL SUITABILITY ASSESSMENT FOR SUSTAINABLE PRODUCTION OF CUCUMBER (Cucumis sativus L.) IN THE SOUTHERN GUINEA SAVANNA ZONE OF NIGERIA

Abstract

The problem of selecting the correct land for the cultivation of a certain crop is a long-standing and mainl empirical issue and nowadays, sustainability is one of the important issues in land use system. A Typic Plinthustalfs soil developed on Pre-Cambrian basement complex rocks was evaluated for its suitability for cucumber (Cucumis sativus L.) in the southern guinea savanna zone of Nigeria. Three mapping units that were established along the topo-sequence and three profile pits that were dug in 2017 were used for the experiment. Linear parametric and square root models were used for assessing the suitability of the soils for
sustainable cucumber production. Land qualities considered in the study were climate, topography, wetness, soil fertility and soil physical properties. Except for the fertility status of the land, other qualities were not a constraint to the production of cucumber at study site. None of the pedon is highly suitable for production of cucumber by both linear and square root models with index of current productivity (IPc) that ranged between 18.7 and 70. Linear model indicated pedon 2 as currently not suitable with IPc of 18.7. Potentially, the index of potential productivity (IPp) ranged between 25 and 70 which rated pedon 1 and 3 as moderately suitable and pedon 2 as marginally suitable for cucumber production by both linear and the square root model. The limiting factors were mainly low levels of available macro-nutrients (N, P, K, Mg), low organic carbon (<0.54%), and low cation exchange capacity (<5.61cmol/kg) in all three pedons studied. Field trial also confirms the claim as application of both organic and NPK fertilizers significantly affect the yield of cucumber in all the pedons. In conclusion, it is therefore recommended that organic fertilizer should be applied for sustainable cucumber production on soils of the studied site.