Root Colonisation and Growth Responses of African Eggplant (Solanum aethiopicum L.) to Indigenous and Commercial Arbuscular Mycorrhizal Fungal Inoculants
Aka Niangoran Marie-Stéphanie KOUADIO *
Laboratory for Agricultural Production Improvement, Training and Research Unit in Agroforestry, Department of Plant biology, Jean LOROUGNON GUEDE University, Daloa, Côte d’Ivoire.
Zrampieu Ange Doriane GONNET
Laboratory for Agricultural Production Improvement, Training and Research Unit in Agroforestry, Jean LOROUGNON GUEDE University, Daloa, Côte d’Ivoire.
Bi Rosin Don-Rodrigue VOKO
Agro-valorization Laboratory, Training and Research Unit in Agroforestry, Department of Biochemistry and Microbiology, Jean LOROUGNON GUEDE University, Daloa, Côte d’Ivoire.
*Author to whom correspondence should be addressed.
Abstract
Background: African eggplant (Solanum aethiopicum L.) is an important vegetable crop in sub-Saharan Africa, but its productivity is constrained by declining soil fertility and increasing reliance on chemical inputs. Arbuscular mycorrhizal fungi (AMF) represent a potential sustainable biofertilisation strategy, although the effectiveness of commercial and indigenous inocula may vary depending on environmental conditions and plant–fungus interactions.
Aims: This study evaluated the ability of one commercial and two indigenous AMF inocula originating from cassava- and maize-associated rhizospheres to colonise S. aethiopicum roots and influence plant growth.
Study Design: Greenhouse experiment conducted in Daloa, Côte d’Ivoire.
Place and Duration of Study: Jean LOROUGNON GUEDE University, Department of Plant Biology, from April to June 2024.
Methodology: A completely randomised design with four treatments and seven replicates was used: a commercial inoculant (CoM), an indigenous cassava-derived inoculum (CaM), an indigenous maize-derived inoculum (MaM), and a non-inoculated control. Mycorrhizal colonisation frequency and intensity were assessed 40 days after transplanting, while plant growth and biomass production were monitored for 60 days.
Results: All three inocula established mycorrhizal colonisation, with colonisation frequencies exceeding 50%, whereas no colonisation was detected in the non-inoculated control. However, colonisation intensity remained low, and no significant differences were observed among the commercial and indigenous inocula. Similarly, no statistically significant treatment differences were detected in plant height, collar diameter, number of leaves, flower-bud production, or fresh aboveground and belowground biomass.
Conclusion: These findings indicate that the indigenous inocula evaluated were capable of colonising S. aethiopicum roots at levels comparable to the commercial inoculant. Under the controlled greenhouse conditions and regular irrigation regime used in this study, AMF inoculation did not result in detectable improvements in eggplant growth. Longer-term experiments using larger root-zone volumes and contrasting water conditions, together with field trials, are needed to determine the agronomic potential of these indigenous inocula for sustainable biofertilisation of African eggplant in Côte d’Ivoire.
Keywords: Sustainable agriculture, biofertilizer, arbuscular mycorrhizae, mycorrhizal colonization