Influence of soil phosphorus fertilizer forms on phosphorus uptake, morphology, and growth of leafy vegetables

Abstract

Phosphorus (P) is an essential plant nutrient that has continued to depreciate in most soils in sub-Saharan Africa, mostly due to adsorption, leaching, and crop uptake. This study was carried out to determine the effect of phosphorus forms and its absence on P uptake, root traits, and growth of leafy vegetables. Five African indigenous vegetable species alongside one exotic vegetable were grown in pots. Each pot was supplied with 49 milligrams of P in the form of KH2PO4, Phytate, rock P, and FePO4 with the control having no P. The P fertilizers were mixed with 1220 g of soil in a ratio of 60:1, sand and loam, to fill the pots before planting. Vegetable seeds were randomly planted and replicated four times, giving rise to 120 pots under investigation. All vegetable species actively utilized KH2PO4 and Phytate to grow and form the highest shoot and root biomass. Spider plants absorbed high levels of P from all the P treatments, but could not convert more of it to biomass formation. African nightshade performed well in KH2PO4 and Phytate, but poorly in the rock P and FePO4. Cowpeas performed well by yielding high-shoot biomass in all the treatments. Cowpea and Ethiopian kale had high biomass when grown in rock P and FePO4. Vegetable species require P for optimal growth, although various species were seen to have different levels of P uptake and utilization efficiency on soluble and slightly soluble fertilizers as well as their ability to grow in P-absent or adsorbed soils.