Pot and Field experiments were conducted to evaluate the dietary minerals and leaf chlorophyll of cassava (Manihot esculenta Crantz) grown on crude oil contaminated soil amended with organic supplements at Ikot Ada Udo, Akwa Ibom State, Nigeria, using appropriate standard methods. Results from the study showed that supplements application led to a reduction in chlorophyll. In the field, chlorophyll content index (CCI), chlorophyll-a, and chlorophyll-b were highest in the TMS 30572 cultivar. This was followed by the Local cultivar while the NR cultivar had the lowest recordings. With the pot experiments however, chlorophyll synthesis was in the order: TMS = LV< NR. An analysis of dietary mineral content revealed that key nutrients such as phosphorus (P), calcium (Ca), potassium (K), and magnesium (Mg) were significantly lower in the leaves than in the roots of the cassava cultivars. On the basis of these findings, the TMS 30572 cultivar is therefore recommended for cultivation with the application of Organic Palm Bunch Ash (OPBA) and Decomposed Poultry Litter (DPL), for the reclamation of crude oil-impacted soils and improved cassava productivity.
Harrison et al. (Tue,) studied this question.