Influence of Bio-rock P fertilizer on nutritional composition of whole maize grains: The case of Madaba and Morogoro, Tanzania

Abstract

This study was designed to understand the influence of Bio-rock P fertilizer as the source of phosphorous on nutritional composition in maize grain. Bio-rock P fertilizer is a preparation made of rock phosphate and phosphate solubilizing bacteria (PSB). The experiment was laid out in randomized complete block design with three replications each receiving five rates of bio-rock phosphate fertilizer (Control, 20 kg P/ha with PSB, 40 kg P/ha with PSB, 60 kg P/ha with PSB and 80 kg P/ha with PSB). The study was carried out at two geographically different sites; Magadu in Morogoro and Madaba in Ruvuma for the duration of 90 days in the 2019 - 2021 cropping season. In both sites, the results showed that, bio-rock phosphate fertilizer rates had no significant influence on percentage protein, carbohydrate, fibre and moisture content. However, Bio-rock P rates had a significant effect on ash and fat contents of maize grains (p<0.05). Bio-rock phosphate fertilizer rates had no significant influence on percentage protein, carbohydrate, fibre and moisture content. For mineral content, there was significant difference in P, K, Mg, and Fe in Magadu and Madaba samples. Therefore, application of bio-rock phosphate increased macronutrients content (ash and fat) and some of micronutrients specifically phosphorous, potassium, magnesium and iron content and as the rates of bio-rock phosphate increased.