Effect of fertilizer Microdosing of and Microbial Inoculation on Pearl Millet ( Pennisetum glaucum (L.) R. Br) Growth on Two Soils of the Peanut Basin of Senegal

Applying a microdose of NPK fertilizer to pearl millet in a greenhouse experiment increased chlorophyll content by 46% and collar diameter by 30% compared to untreated controls. Inoculation with arbuscular mycorrhizal fungi (AMF) and plant growth-promoting rhizobacteria (PGPR), alone or combined, produced more variable effects; shoot biomass improved up to 20%, but root biomass showed no significant change (1.02% increase). A site effect was observed: growth at Touba Toul was about 60% higher than at Gossas. Combining biofertilization with fertilizer microdosing may offer a sustainable strategy for pearl millet production in the Sahel.

Study at a glance

Abstract

Pearl millet ( Pennisetum glaucum (L.) R. Br) is a very important cereal crop in the semi-arid regions of West Africa, serving as a primary food source for local populations. Therefore, its productivity remains lowered by soil degradation and low availability of inputs as fertilizers. In this context, biofertilizers and organic amendments offer sustainable and ecological alternatives for enhancing crop performance. This study aims to contribute to improve pearl millet production through the application of biofertilizers arbuscular mycorrhizal fungi (AMF) and plant growth-promoting rhizobacteria (PGPR) combined with microdose NPK. The research focuses on two soils of the peanut basin of Senegal (Touba Toul and Gossas). Thus, a greenhouse experiment was conducted using a completely randomized block design with five treatments (control, microdose, fungal inoculation (AMF), bacterial inoculation (PGPR) and dual inoculation (AMF+PGPR)) and five replicates, on each of the two soils. The parameters assessed included mycorrhization, collar diameter, number of leaves, chlorophyll content, shoot and root biomass, and ears length. Results revealed that, the microdose generated the best agronomic performance, including 46% increase in chlorophyll content and 30% increase in collar diameter compared to control. The AMF, PGPR and AMF+PGPR treatments showed more variable effects. While close to some parameters such as shoot biomass, improved significantly (up to 20% increase), but with no significant improvement in root biomass (1.02% increase). A notable site effect was observed: Touba Toul proved to be more favourable for millet growth, with an overall performance increase of around 60% compared to Gossas. These findings suggest that combining biofertilization with fertilizer microdosing could be a promising strategy for sustainable pearl millet production in sahelian regions.