Phenotypic Characterization and Multivariate Analysis of Fifteen Maize Lines developed by Induced Mutation in Daloa (Côte d’Ivoire)

In Côte d'Ivoire, maize is an important staple food for a large part of the population. However, its culture faces many constraints related to soil degradation, climate change and genetic degeneration of cultivated varieties. In order to create new varieties adapted to these constraints, mutant maize Lines have been developed using the gamma radiation technique. The present study aims to phenotyping 15 mutant Lines from the sixth generation of self-pollination, in order to characterize them and to give information on their genetic diversity. For this, an experiment in a randomized complete block design with three replications was conducted. Thirteen traits were evaluated and they showed wide variation not only between the mutant Lines but also between them and the non-irradiated control. Multivariate analysis structured this variability into five distinct groups with specific traits. The interest of the revealed traits and the future use of these mutant Lines are discussed. Keywords: maize, gamma radiation, induce mutation, phenotypic characterization DOI: 10.7176/JBAH/13-18-05 Publication date:December 31st 202

Population dynamics of 15 fish species in Grand-Lahou lagoon (West Africa, Côte d'Ivoire) | IJB 2022

This study described growth, mortality, recruitment patterns and exploitation rates of 15 fish species in Grand-Lahou lagoon (Côte d’Ivoire). Monthly length-frequency data collected from artisanal fisheries from November 2013 to October 2014 were analyzed with FiSAT software using the ELEFAN package to estimate the population parameters of fishes. Asymptotic values for total length (L∞) ranged from 15.75 cm for Synodontis schall to 59.80 cm for Trachinotus teraia. Growth rate (k) varied from 0.19 for Coptodon guineensis to 0.98 for Caranx hippos. The growth performance index estimates were close to the values found by other authors for most of the fish species. The total mortality (Z) high values were recorded for Synodontis schall (Z= 4.15 year-1; M = 2.50 year-1) Schilbe mandibularis (Z= 2.19 year-1; M=1.33 year-1). Fishing mortality (F) and exploitation rate (E) were found to be less than the optimum levels of exploitation for most fish species. The exploitation rate (E) was higher than the maximum sustainable yield (Emax) for Caranx hippos and higher than E0.5 for Eucinostomus melanopterus, Elops lacerta and Synodontis schall. Recruitment was noted as year-round and bimodal for most studied populations. These results demonstrate that some fish stocks necessitate effective management measures particularly C. hippos, E. melanopterus, E. lacerta and S. schall. Published by the International Journal of Biosciences | IJ