Performance of Struvite and Organomineral Fertilizers Compared to Traditional Source of Phosphorus in Maize Cultivation on Tropical Soils

Abstract

In highly weathered soils, natural fertility is often compromised due to low phosphorus (P) availability. Additionally, there’s an increasing urgency to explore alternative P sources to enhance agricultural productivity and sustainability because P sources are finite. The objectives of this study were to compare the agronomic effectiveness of struvite (Est), organomineral (OM), and thermophosphate (ThermoP) with triple superphosphate (TSP) in increasing maize yields in sandy loam and clayey tropical soils. Investigate the effects of alternative phosphorus fertilizers on the phosphorus use efficiency of maize over two consecutive cropping cycles. Determine the feasibility of these alternative phosphorus sources as replacements for conventional TSP to promote sustainable nutrient management practices in agriculture. In a greenhouse, sandy loam and clayey soils were fertilized with four P sources: OM, Est, ThermoP, and TSP. Two successive maize crops were grown, with each treatment receiving a P rate of 100 mg kg^− 1. Soil and plant chemical analyses were carried out and then the following fertilizer efficiency indices were calculated: agronomic efficiency index (AEI), agronomic efficiency (AE), crop recovery efficiency (CE), phosphorus utilization efficiency (PUE), P recovery efficiency (PUpE), and physiological efficiency (PE). Est and OM had higher agronomic efficiencies than TSP in sandy soils. The alternative sources exhibited almost 2-fold more efficiency in the sandy loam compared to the clayey soil. The superior performance of Est was attributed to its slow nutrient release and physicochemical properties that potentially improve soil quality. Regarding PE, OM and TSP led the highest values in both cultivations in sandy loam soil. In the 1st crop cycle, the average PE of these two treatments was ∼ 215 g g^− 1 while in the 2nd the average was ∼ 181 g g^− 1. The Est fertilizer resulted in the highest values of CE, PUpE, and PUE. Multivariate analysis further supported these observations. Est and OM, can effectively replace conventional TSP in maize cultivation, resulting in better plant performance and nutrient utilization. Consequently, these alternative fertilizers offer the potential for sustainable nutrient management strategies.