Genetic Adaptability of Sarotherodon Melanotheron to Polycyclic Aromatic Hydrocarbons (PAHs) in Some Senegal Hydrosystems

The objective of this study is to evaluate the level of Polycyclic Aromatic Hydrocarbons (PAH) contamination at the Sine-Saloum (Foundiougne, Kaolack and Missirah), Hann Bay and Niayes (1 and 2) sites in Sénégal and genetic ecotoxicology of Sarotherodon melanotheron specimens from these sites.The genes of the specimens were studied by the enzymatic electrophoresis technique. Seven enzymatic systems (ADH, AAT, IDHP, MDH, PGM, GPI and EST) were analyzed. The analysis of the PAHs was carried out by gas chromatography coupled to mass spectrometry (GCMS). Populations of Sarotherodon melanotheron and sediments used for PAH measurements were sampled in 2009. Chemical characterization of the sampling sites revealed a high concentration of PAHs at Foundiougne and Hann Bay. The high pollution of environment is characterized by PAH napht (Foundiougne (14 378 ng/g) ; Hann Bay (5856 ng/g). The analysis of allelic variability showed the existence of an adaptive polymorphism at the PGM locus in S. melanotheron. The particularly low frequencies of the PGM * 105 allele in populations of disturbed environment (Foundiougne, Kaolack, Hann Bay, Niayes 1 and Niayes 2) suggest its involvement in the response to environmental stress. A negative correlation was observed between the PGM, IDHP and MDH-1 locus and PAH. The presence of PAHs in the environmentcauses to a decrease in the frequency of the PGM * 105 alleleatS. melanotheronspecimens

Agro-morphological Characterization of Myrianthus Arboreus (P. Beauv) in Côte d’Ivoire

The objective of this study is to evaluate the agro-morphologicals parameters of Myrianthus arboreus in five localities of the Côte d’Ivoire.Seventy-five individuals of Myrianthus arboreus collected in five localities of Côte d’Ivoire (Abengourou, Adzopé, Daloa, Diabo and Zouan Hounien), have been evaluated agro-morphologically. Twelve characters selected from the descriptors of this plant were used in this study. Statistical analysis revealed a high variability between the individuals collected. But a higher value of parameters tested was recorded in Abengourou than Diabo. Positive correlations were observed between leaf, production parameters and between foliage and production parameters. Hierarchical Classification Analysis associated with Discriminant Factor Analysis showed that individuals tested were split in three groups with complementary characteristics. Among parameters tested leaves width and fruits full quarter’s number were revealed as discriminating factors

Agro-morphological variability of Bottle Gourd accessions Lagenaria siceraria (Molina) Standl in Côte d’Ivoire

Bottle gourd Lagenaria siceraria (Molina) Standl is one of the oleaginous cucurbits grown in Côte d'Ivoire with socio-economic and food importance that could play an important role in food security. The increase in the production of this species for improvement of plant yield remains a major challenge that begins with the agro-morphological characterization of local varieties present in different production areas. The objective of this study is to estimate agro-morphological variability within the Lagenaria siceraria seed collection of Nangui Abrogoua University. The study focused on 26 accessions collected in the different production areas of the species. The experimental design is a randomized complementary block. Descriptive analyzes under the observation of fourteen descriptors showed the existence of a great variability between accessions for the yield characters. Multiple variance analysis showed that there is a highly significant difference between accessions and provenances for the majority of traits studied. The structuring of accessions according to areas collection revealed by principal component analysis is confirmed by discriminant factor analysis. The classification of accessions and identification of the groups were carried out by hierarchical ascending classification which made it possible to elaborate a dendrogram which presents two groups of phenotypic diversity. It appears that the most relevant variables that describe the best variability between groups are fruit size (FH), fruit weight (FW), number of seed (NS), and seed weight (SW). These analyzed characters can thus constitute basic criteria to differentiate accessions and to be used in studies of morphological diversity of L. siceraria

Effect of the seeds provenance and treatment on the germination rate and plants growth of four forest trees species of Côte d’Ivoire

International audienceThe rapid rate of deforestation in Côte d’Ivoire has led to loss of plant species diversity and also threatens some commercial tree species with extinction. Some reforestation and afforestation has been completed. However, for some species, the numbers of surviving transplants has declined. Hence, it is necessary to develop properly adapted and resilient genotypes that can effectively support the programs of forest restoration. In this context we evaluated the effects of the provenances of seeds and of various treatments on the germination rates and on plant growth of four commercial trees species (Pycnanthus angolensis, Terminalia superba, Mansonia altissima and Pterygota macrocarpa). We analyzed these parameters for seeds of three provenances (Daloa, Akoupé and Daoukro) of four species and for thirty plants aged 6 months per provenance. Time to begin germination and time to reach maximum germination were similar among species, and were not influenced by either treatment or provenance. Untreated seeds and those soaked for 24 and 48 h in water at room temperature yielded the highest germination rates, irrespective of species or provenance. The one exception was P. angolensis, for which no germination was recorded. Within species, some provenances produced higher germination percentages than did others. No clear relationship was computed between the germination rate and the morphometric characteristics of the seeds which varied significantly between provenances. Plant growth and morphological variability also depended greatly on provenance. Genetic factors might be implicated, therefore provenance trials should be undertaken and evaluated. Furthermore, molecular analysis should be undertaken to confirm the implications of genetic factors and allow for genetic selection

Effets du traitement des plants de riz (Oryza sativa L.) au chlorure de sodium sur la synthèse et accumulation des sucres totaux et des composés phénoliques ethanosolubles dans les feuilles et racines

Objectif: Ce travail a été réalisé pour évaluer la capacité du riz (Oryza sativa L.) à élaborer des stratégies d’acclimatation au stress salin en prenant la teneur des feuilles et racines en sucres totaux et composés phénoliques comme références. Ces composés sont synthétisés au cours du stress abiotique chez la plupart les plantes.Méthodologie et Résultats: Les plants de 7, 60 et 90 jours des variétés Zouhn-kinmin et Kpeulia ont été traités au NaCl 5 ou 10 gL-1, et le dosage à 0, 1, 2, 3 et 4ème jours après traitement. Les résultats indiquent une quantité importante de sucres totaux avec 5 gL-1 de NaCl chez les plants de Zouhn-kinmin de 60 jours [562,83 (feuilles) et 222,83 (racines) μg Glucose gMF-1]. Chez Kpeulia, l’accumulation a été maximale avec 10 gL-1 de NaCl. Chez ces variétés, la synthèse des phénols a été forte dans les feuilles et racines des lants de 90 jours avec NaCl 5 gL-1.Conclusion et Application des résultats: La teneur en sucres totaux et en composés phénoliques exprimée chez ces deux variétés montre que la variété Zouhn-kinmin serait plus tolérante au stress salin pendant la phase végétative et la variété Kpeulia à la phase de reproduction. Pour l’étude donc du comportement desplants de riz au taux souvent élevé dans le sol des engrais mal appliqués, le NaCl peut être utilisé.Mots clés: Oryza sativa, stress salin, sucres totaux, composés phénoliquesEnglish AbstractObjective: This work was done to evaluate ability of rice (Oryza sativa L.) to develop salt stress acclimation strategies by taking leaf and root content of total sugars and phenolic compounds as references. These compounds are synthesized during abiotic stress in most plantsMethodology and Results: Plants of 7, 60 and 90 days of Zouhn-kinmin and Kpeulia varieties were treated with NaCl 5 or 10 gL-1, and dosage at 0, 1, 2, 3 and 4 days after treatment. Results indicate a significant amount of total sugars with 5 gL-1 of NaCl in Zouhn-kinmin plants of 60 days [562.83 (leaves) and 222.83  (roots) μg Glucose gMF-1]. In Kpeulia, accumulation was maximal with 10 gL-1 of NaCl. In these varieties, phenol synthesis was strong in leaves and roots of 90-day-old plants with NaCl 5 gL-1.Conclusion and Application of results: Total sugar and phenol compound content expressed in these two varieties shows that Zouhn-kinmin variety is more tolerant of salt stress during vegetative phase and Kpeulia variety in reproductive phase. For study of the behavior of rice plants at the often high rate in the soil of poorly applied fertilizers, NaCl can be used.Keywords: Oryza sativa, salt stress, total sugars, phenolic compound