Author(s)

Franklin Tounkam Ketchiemo^1,2, Beaulys Fotso^1,3, Astride Stéphanie Mouafi Djabou^1,3, Victor Jos Eyamo Evina^1,4, Japhet Youri Essambita^1,5, Franck Maxime Ewane Tang^1,2, Nicolas Niemenak^1*

¹Laboratory of Plant Physiology and Biochemistry, Department of Biological Sciences, Higher Teacher Training College, University of Yaounde I, Yaounde, Cameroon.
²Department of Plant Biology, Faculty of Sciences, University of Yaounde I, Yaounde, Cameroon.
³Faculty of Agronomy and Agricultural Sciences, Bafia Annex, University of Dschang, Dschang, Cameroon.
⁴Applied Biotechnology Engineering Laboratory, Department of Agriculture and Agropastoral, Higher Teacher Training College, University of Ebolowa, Ebolowa, Cameroon.
⁵Plant Physiology Improvement Unit, Laboratory of Biotechnology and Environment, Department of Plant Biology, Faculty of Sciences, University of Yaounde I, Yaounde, Cameroon.

This study aims to investigate the abundance of AMF according to soil properties and altitudes in different cacao plantations of Cameroon. Physico-chemical analyses were made on soil samples collected from three agro-ecological zones. Soil samples were also used to evaluate directly the AMF abundance following the various altitudes and after trapping by sorghum plant. The results showed that soil properties, AMF spore abundances and colonization fluctuated significantly at different altitudes. The most represented texture was sandy loam. The bimodal zone presented a homogeneous texture (sandy loam) in all its localities. Cacao soil chemical characteristics showed that, the highest nitrogen rate (0.47%; p < 0.05, Scott-Knott test) was recorded at Melong in a monomodal zone while Tonga in the Western highlands displayed the lowest rate (0.13%). Soil P concentration was significantly high in monomodal zones (Mbanga and Melong). Soil pH level indicated that the soil from Tonga in the Western highlands was neutral (pH = 6.67), and soils of other localities under study were acidic with the lowest (4.75) pH level recorded at Melong in a monomodal zone. In soil samples, the highest spore density (1.03 spores/g soil) was observed at Ntui in Bimodal zone, while the lowest spore density (0.26 spores/g soil) was observed at Bafang in the Western highlands. Root colonization showed that the sample from Bokito in a bimodal zone displayed the best frequency of mycorrhization (86.11%) while the sample from Bafang in the Western highlands recorded the lowest (27.11%). The PCA analysis highlighted that available phosphorus, pH and altitude all strongly correlated with AMF root colonization ability and can be used as a predictor of AMF colonization ability in cacao rhizosphere.

Agroecological Zone, Altitude Variations, Arbuscular Mycorrhizal Fungi, Soil Properties, Theobroma cacao

Ketchiemo, F. , Fotso, B. , Djabou, A. , Evina, V. , Essambita, J. , Tang, F. and Niemenak, N. (2024) Soil Physico-Chemical Properties and Different Altitudes Affect Arbuscular Mycorrhizal Fungi Abundance and Colonization in Cacao Plantations of Cameroon. American Journal of Plant Sciences, 15, 57-82. doi: 10.4236/ajps.2024.152005.