Evaluation of the micronutrient fertility of Nigeria's semi-arid savannah soils: Boron and molybdenum

Boron and molybdenum fertility of 50 representative savannah soils of Nigeria were evaluated through laboratory analyses and greenhouse cropping. Results revealed generally low levels of both nutrients (average of 0.25 and 0.11 ppm B and Mo respectively) although apprecialbe yield responses (dry matter) were obtained in only a relatively few cases. The low nutrient levels were attributed to the interplay of the low organic matter levels and the coarse-textured nature of the soils. These two soil properties (together with exchangeable Ca levels in the case of B) appeared to have significantly influenced the uptake of the two nutrients by peanut plants under greenhouse conditions. The extractable B and Mo levels in many of the soils fell within the range of the critical values reported in the literature. It is thus concluded that incipient deficiencies of these nutrients in field crops may be widespread in Nigeria's savannah.