Evaluation of Local Common Bean (Phaseolus vulgaris L.) Genotypes for Resistance to Fungal Diseases in the Bimodal-rainfall Forest Zone of Cameroon
Tchang Hourounou Nineck
Laboratory of Genetic and Plant Improvement of Department of Plant Biology, Faculty of Science, University of Yaoundé I, Po. Box. 812, Cameroon.
Mboussi Serge Bertrant
Laboratory of biotechnology, University Institute of Technology, The University of Douala. P.O. Box 8698 Douala, Cameroon.
Molo Thierry
Laboratory of Genetic and Plant Improvement of Department of Plant Biology, Faculty of Science, University of Yaoundé I, Po. Box. 812, Cameroon and Centre de Recherche et d’Accompagnement des Producteurs Agro-pastoraux du Cameroun (CRAPAC), Cameroon.
Molo Nathalie Shérifa
Laboratory of Genetic and Plant Improvement of Department of Plant Biology, Faculty of Science, University of Yaoundé I, Po. Box. 812, Cameroon and Centre de Recherche et d’Accompagnement des Producteurs Agro-pastoraux du Cameroun (CRAPAC), Cameroon.
Ndzana Ndzana Emile Lionel Landry
Laboratory of Genetic and Plant Improvement of Department of Plant Biology, Faculty of Science, University of Yaoundé I, Po. Box. 812, Cameroon and Centre de Recherche et d’Accompagnement des Producteurs Agro-pastoraux du Cameroun (CRAPAC), Cameroon.
Likeng-Li-Ngue Benoit Constant *
Laboratory of Genetic and Plant Improvement of Department of Plant Biology, Faculty of Science, University of Yaoundé I, Po. Box. 812, Cameroon and Centre de Recherche et d’Accompagnement des Producteurs Agro-pastoraux du Cameroun (CRAPAC), Cameroon.
*Author to whom correspondence should be addressed.
Abstract
The general objective of the present study was to evaluate the susceptibility to fungal diseases of some bean collections in the bimodal rainfall forest zone of Cameroon. To this end, 12 bean collections from Foumbot were grown at the University of Yaoundé I in a completely randomized block design without phytosanitary treatments. Symptoms identified on the leaves of diseased plants were used to characterize the fungal agents in the laboratory using an identification key. Incidence and severity were assessed, as well as the number of pods and seeds in plants under fungal pressure. Following the evolution of symptoms, all collections showed fungal disease attacks at different rates. Macroscopic and microscopic laboratory observations identified Sclerotinia sclerotiorum, Uromices appendiculatus and Fusarium solani as the fungal agents responsible for these symptoms. The incidence of disease caused by F. solani was lower in the NJBPRNV (16.67%) and NJBV (22.22%) collections, as was severity (3.33% and 4.44%). On the other hand, the LGRTE (47.06%) and GGRBE (44.44%) LGRV (43.75%) collections showed high incidences of disease caused by S. sclerotiorum, U. appendiculatus and F. solani respectively. Considering the number of seeds, the KPGPV (403.2 seeds) and KPGPTV (350.4 seeds) collections recorded the highest number of seeds, compared with the GGRBE (15.93 seeds); LGRTE (23.87 seeds); GGRBTE (25.53 seeds); LGRV (42.4 seeds) and GGRTE (52.2 seeds) collections. However, the NJBPRNV collection requires special attention in varietal creation, given its greater resistance to the fungal diseases identified.
Keywords: Incidence, fungal agents, sensitivity, severity, Phaseolus vulgaris, fungal diseases, Fusarium solani, fungal pressure, common bean