Browsing by Author "Daouda, K."
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Item Assessment of Bacterial Biocontrol agents Formulations against Anthracnose of Cashew (Anacardium occidentale L.) in Côte d’Ivoire(Ms. M. B. Mondal, 2024-09) Armist, TA; Fulgence, KY; Francine, AMD; Kouabenan, A; Mireille, A-BWA; Daouda, K.The cashew tree (Anacardium occidentale L.) is of vital importance to the Ivorian economy. Côte d’Ivoire is first world producer. However, its cultivation faces several constraints linked to anthracnose. The aim of this study was to assess the efficacy of two formulated bacterial biocontrol agents against anthracnose of cashew. To this end, in vitro confrontation tests were carried out against Colletotrichum gloeosporioides with two previously formulated bacterial biopesticides. Biocontrol tests were then carried out against anthracnose in greenhouses and cashew plantations. The results showed that the two bacterial biocontrol agents tested controlled in vitro the proliferation of Colletotrichum gloeosporioides responsible for anthracnose and significantly reduced the disease severity index on cashew seedlings in the greenhouse. In vitro, inhibition rates ranging from 70.16±6.9 to 72.65±6.5% were observed on the mycelial growth of Colletotrichum gloeosporioides. In the greenhouse and in cashew plantations, a sharp reduction in the anthracnose severity index was observed. In the greenhouse, anthracnose reduction rates by the two bacterial biocontrol agents ranged from 62.80 ± 5.2% to 85.95 ± 2.8%. In cashew plantations, the reduction rates varied from 42.24 to 41.05%. In view of the above, these two bacterial biocontrol agents could be used for biological control of cashew anthracnose in Côte d'Ivoire.Item Contribution to the Identification and Study of the Pathogenicity of Bacteria Responsible for Cassava Root Rot in Côte d'Ivoire Production Zones(Ms. M. B. Mondal, 2024-01) Jacques-Edouard, YK; Henoc, KKY; Didier, KK; Jean-Martial, KKF; Noël, KK; Fatogoma, S; Daouda, K.Background and Objective: Cassava is an important crop for the Ivorian population. However, yields are relatively low. This low productivity is due to cassava root rots, which are sometimes caused by bacteria. The general objective was to identify the main bacterial diseases responsible for cassava tuberous root rot in production areas in Côte d'Ivoire. Specifically, to identify pathogenic bacteria and then to assess the pathogenicity of the bacterial strains isolated. Material and Methods: The plant material consisted of tuberous cassava roots affected by rot. Decay-causing bacteria were isolated on YPGA (Yeast extract Peptone Glucose Agar) culture medium. Strain identification was carried out using the API 20 E and 20NE gallery. Tuberous cassava roots were perforated with a punch and inoculated with bacterial inoculum calibrated to an optical density of 0.2 at a wavelength of 600 nm, corresponding to 108. Results: 174 strains were isolated. The highest proportions of strains were obtained in the localities of Ferké and Man, with 19 and 26% respectively. The bacterial species identified were Roualtella planticola, Serratia liquefaciens, Serratia marcescens, Burkholderia cepacia, Chromobacterium violaceum, Erwinia spp, Enterobacter cloacae, Klebseilla pneumoniae spp ozaenae and Raoutellia ornithinolytica. The Erwinia species was the most frequent in five localities, with proportions of 100 and 71.4% respectively in Agboville and Yamoussoukro. Results showed that 91.5% of bacterial strains tested caused rot (soft or dry). On the other hand, 52.4% of bacterial strains induced dry rot and around 39% induced soft rot. Conclusion: Various bacterial species were identified in this study. In addition, these species vary in their germinative capacity.Item Evaluation of the Sensitivity of Strains of phytophthora spp Cause of Brown Rot of Cocoa (Theobroma cacao l.) against to Limocide 60 ME (An Extract of Sweet Orange Essential Oil)(Ms. M. B. Mondal, 2025-06) Henri, NP; Brahima, C; Alban, MKA; Didier, KK; Edouard, YKJ; Martial, KKJF; Franck, ZB; Martial, KNG; Daouda, K.Ivory Coast produces nearly 2 million tons, which represents 15% of the Gross Domestic Product (GDP), more than 50% of exports and provides seven million jobs to Ivorians. However, its production is severely limited by the brown rot disease of cocoa pods. In order to increase production and improve public health and environmental problems, sweet orange essential oil extract was used to combat cocoa brown rot disease caused by Phytophthora spp. A morphological description of the pathogen was carried out. The effectiveness of Limocide was tested at doses of 100, 200, 400, 800 ppm and compared to NECO and Callomil super. Limocide, Callomil super and NECO significantly inhibited the in vitro mycelial growth of Phytophthora spp with 29.76, 89.41 and 100% respectively after six days of incubation. The minimum concentrations that inhibit 50% (IC 50 ) the growth of the fungus were, respectively, 929, 1521 and 348 ppm for Limocide , Callomil super and NECO. The biofungicide Limocide has proven its ability to control brown rot of cocoa pods under controlled conditions.Item Pathogenic Susceptibility of Cashew (Anacardium occidentale L.) to Twelve Isolates of Colletotrichum sp Present on Six Weeds in Cashew Orchards in Côte d'Ivoire(Ms. M. B. Mondal, 2025-02) Aboulaye, T; Sibirina, S; R. E., AA; Arsène, SN; Karidia, T-O; Daouda, K.Cashew nuts are one of the agricultural products that contribute significantly to Côte d'Ivoire's economic development. However, cashew nut production in Côte d'Ivoire is threatened by anthracnose. Reducing anthracnose proliferation factors could reduce its impact on cashew trees. The aim of the study was to assess the virulence of Colletotrichum sp. isolated from weeds in cashew trees. It assessed the pathogenicity of 12 isolates of Colletotrichum sp. extracted from six weeds on cashew plants. The inocula were prepared by scraping the mycelium of each fungus in 10 ml of sterile distilled water. The spore suspension was collected and calibrated at 4.6.106 conidia/ml using a Malassez cell. This suspension was applied by spraying to the leaves of 30-day-old cashew plants. The parameters assessed were symptom incidence and severity index. All isolates tested induced symptoms characteristic of anthracnose on cashew plants. There was a significant difference between isolates in terms of their virulence. The highest incidence of 90% was obtained on plants inoculated with the ColE2 isolate and the lowest incidence of 30% was obtained on plants inoculated with the ColN3 isolate. The highest severity index of 7.66 was obtained on plants inoculated with the ColE3 isolate and the lowest severity index of 2.00 was obtained on plants inoculated with the ColN3 isolate. These results show that Daniellia oliveri (Rolfe), Vitellaria paradoxa (G), Micuna pruriens (L.), Blighia sapida (K. Koenig), Albizia zygia (DC) and Pterocarpus erinaceus (Poir) are hosts of anthracnose in cashew orchards in Côte d'Ivoire. Their integration into cashew pathogen control strategies is necessary.Item Susceptibility of Mycosphaerella fijiensis to Mefentrifluconazole in Industrial Banana Plantations in Côte d'Ivoire : An In vitro Study(Ms. M. B. Mondal, 2024-01) Edouard, YKJ; Henri, NP; Seydou, T; Bertrand, GN; Brahima, C; Jean-Martial, KKF; Daouda, K.Banana Sigatoka, caused by Mycosphaerella fijiensis, severely impacts banana production in Côte d'Ivoire. This study evaluates the susceptibility of M. fijiensis isolates to mefentrifluconazole, a new triazole fungicide, compared to difenoconazole. In vitro tests on 17 isolates from industrial plantations revealed IC50 values ranging from 0.005 to 0.073 mg/L (average 0.037 mg/L), indicating high sensitivity. Growth inhibition rates were higher for mefentrifluconazole, demonstrating its superior efficacy. These results suggest mefentrifluconazole as a promising alternative for managing black spot and mitigating resistance development.