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Context: In Côte d’Ivoire, industrial banana plantations are faced with the problem of weediness. However, the use of herbicides as a means of control presents significant risks for human health and the environment. The abandonment of these products for more ecological alternatives such as cover crops is imminent. Aims: This study aimed to compare the relative abundance and the density of the main plant-parasitic nematodes in the roots of banana and cover crops according to three weed management treatments. Study Design and Methodology: The experimental design was a three-repeat Fisher block of three treatments consisting of implementation of A. repens and D. adscendens as cover crops and spraying of two synthetic herbicides (glufosinate and glyphosate) for weed management. The relative abundance and density of nematodes in the roots of banana and cover crops were assessed quarterly after extraction by the rapid double centrifugation-flotation method and enumeration under an optical microscope. Results: Both cover crops and banana plants had their roots infested by the major parasitic nematodes evaluated (Radopholus similis, Pratylenchus spp., Helicotylenchus spp., Meloidogyne spp., Rotylenchulus reniformis and Hoplolaimus pararobustus). These infestations were not a function of weed management treatments. Compared to the use of herbicides, A. repens and D. adscendens used as ground cover did not significantly increase or decrease nematode dynamics in the plots. Individuals extracted from the roots of the cover crops, and particularly from D. adscendens, were more numerous than from the roots of the banana plants. In terms of proportions, Pratylenchus spp., R. similis, Helicotylenchus spp. and Meloidogyne spp. were most abundant. R. reniformis and H. pararobustus as well as various nematodes (plant parasites: Hirschmanniella spp., Xiphinema spp., ..., and non-plant parasites: fungivorous, carnivorous, bacterivorous, ...) were in the minority. Conclusion: The results, particularly those of A. repens, could be useful in the biological, ecological and sustainable management of weed in banana plantations without important risks of pest pressure.

Yam (Dioscorea spp) is a major food crop in many parts of the world, particularly in West Africa. In Côte d'Ivoire, yam occupies the first place in terms of food crops. However, this crop is faced with enormous parasitic constraints including leaf diseases. Anthracnose is the most frequent fungal disease in Côte d'Ivoire and has a formidable impact on yam production as it causes yield losses that can reach more than 90%. This study was conducted to evaluate the effect of three biofungicides (NECO, ASTOUN, FERCA) and a synthetic fungicide (REFERENCE) on the mycelial growth of Colletotrichum sp, Pestalotia sp, Botryodiplodia sp and Curvularia sp, four fungi responsible for yam anthracnose. It revealed that the biofungicides NECO and ASTOUN were the most effective on the in vitro mycelial growth of Colletotrichum sp with respective inhibition rates of 92.67 and 97.06% at the 2000 ppm dose. The synthetic fungicide REFERENCE and the biofungicide ASTOUN were more fungitoxic on the fungus Pestalotia sp by reducing its growth to 100% at 100 ppm and 1000 ppm respectively. FERCA biofungicide was the least effective on mycelial growth of the pathogens. These fungicides may provide a basis for field control of anthracnose of yam in Côte d'Ivoire.

Mango bacterial black spot is an emerging disease in Cote d'Ivoire and the damage caused is becoming more and more significant. This study aims at diagnosing bacterial black spot incidence and severity level in regions of intensive mango production. Surveys were carried out during the vegetative stage of mango trees from July to August 2019 and the fruiting stage from March to April 2020 in 50 orchards in the Poro and Tchologo regions. In each orchard, 5 mango trees regularly dispersed over an area of 0.5 ha were assessed. On each tree, three (3) twigs per cardinal point were selected then the leaves counted and the leaf area covered by bacterial black spot symptoms determined. At fruiting stage, bacterial black spot severity on 40 fruits per selected tree, at the rate of 10 fruits per cardinal point was assessed. Bacterial black spot symptoms were observed in all orchards and the bacterium, Xanthomonas campestris pv. Mangiferaeindicae, was systematically isolated basing on symptoms taken from the leaves and fruits collected. Statistical analysis of the mean incidence and severity per town revealed a variability of 83.2% up to 90% on the leaves and 41.42% up to 55% on the fruits regarding incidence. As for severity, the highest values, 10.58% and 5.23% on leaves and fruits respectively were recorded in the department of Tafiere. Mango bacterial black spot is found in orchards located in the Poro and Tchologo regions. Incidence and severity are strongly related to the humidity conditions of the production area.

Objectifs : Les cercosporioses noire et jaune causées respectivement par les champignons ascomycètes Mycosphaerella fijiensis et Mycosphaerella musicola sont les maladies foliaires les plus dévastatrices en culture du bananier. La cercosporioses noire ou maladie des raies noires (MRN) est considérée comme la plus contraignante et se traduit par des pertes de rendement allant de 30 à 80 %. La présente étude se propose d’actualiser la carte de distribution géographique des cercosporioses noire et jaune en Côte d’Ivoire par l’évaluation sanitaire des bananeraies dans les principales zones de production et de caractériser la variabilité des isolats de Mycosphaerella spp. isolés.Méthodologie et résultats : Pour se faire, des prospections ont été effectuées pendant 3 années successives dans des zones préalablement sélectionnées de production de banane dessert ou de banane plantain sur la base de la diversité des conditions écologiques et la facilité d’accès. Les paramètres phytopathologiques observées pendant ces prospections ont été la plus jeune feuille touchée par la maladie (PJFT), la plus jeune feuille nécrosée (PJFN) et le nombre de feuilles vivantes (NFV) sur les bananiers. Les résultats ont montré que la cercosporiose noire est bien établie dans toutes les plantations prospectées soit 100 % et que la cercosporiose jaune est présente seulement dans 3 zones agro-écologiques (ZAE II, ZAE III et ZAE IV), soit 8,79 % des plantations prospectées. La sévérité des attaques dues à Mycosphaerella spp. a varié selon les cultivars de bananes et de bananes plantain rencontrés et également en fonction de l’agro-écologie des régions de production. Les pathogènes isolés et identifiés ont montré que les phénotypes diffèrent dans la quasi-totalité des sites visités. Les caractéristiques phénotypiques de l’aspect noir du revers des boîtes de Pétri et non jaune des cultures ont permis de suspecter Mycosphaerella fijiensis.Conclusion et application des résultats : Cette étude a permis de faire ressortir dans toutes les zones agro-écologiques, le caractère épidémique de la cercosporiose noire dans les conditions naturelles d’infestation de production. La cercosporiose jaune est présente uniquement dans les zones agro-écologiques II, III et V. Les résultats de cette étude ont montré une variabilité entre les isolats de Mycosphaerella spp. et aideront à envisager une méthode de lutte alternative à la lutte chimique contre la maladie des raies noires. Objective: Black and Yellow Sigatoka caused by the ascomycete fungi Mycosphaerella fijiensis and Mycosphaerella musicola, respectively, are the most devastating foliar diseases of banana. The Black Sigatoka or Black leaf streak disease (BLSD) is considered the most damaging and results in yield losses ranging from 30 to 80%. The present study aims at updating the geographical distribution map of black and yellow Sigatoka in Côte d’Ivoire by assessing the sanitary status of banana plantations in the main production areas and characterizing the variability of isolated Mycosphaerella spp.Methodology and results: To do so, surveys were carried out during 3 successive years in previously selected areas of dessert banana or plantain production based on the diversity of ecological conditions and ease of access. The phytopathological parameters observed during these surveys were the youngest leaf affected by the disease (YLA), the youngest necrotic leaf (YNL) and the number of living leaves (NLL) on banana plants. The results showed that black Sigatoka was well established in all the plantations surveyed, i.e. 100%, and that yellow Sigatoka was present only in 3 agro-ecological zones (ZAE II, ZAE III and ZAE IV), i.e. 8.79% of the plantations surveyed. The severity of attacks due to Mycosphaerella spp. varied according to the banana and plantain cultivars encountered and according to the agro-ecology of the production regions. The pathogens isolated and identified showed that the phenotypes differed in almost all the sites visited. The phenotypic characteristics of the black aspect of the reverse side of the Petri dishes and the non-yellow aspect of the crops allowed to suspect Mycosphaerella fijiensis.Conclusion and application of results : This study allowed to highlight in all the agro-ecological zones, the epidemic character of the Black Sigatoka in the natural conditions of infestation of production. Yellow Sigatoka is present only in agro-ecological zones II, III and V. The results of this study showed variability among isolates of Mycosphaerella spp. and will help to consider an alternative control method to chemical control of Black leaf streak disease.

Pineapple has several types of organs that can be used for its multiplication. Its natural multiplication is particularly slow, as it is necessarily vegetative because the species is self-sterile (on average 2 suckers per strain in six months). The supply of pineapple rejects is not always easy for those who want to grow pineapple on large areas. This study was initiated to improve the production of MD2 pineapple seed (suckers or vivo plant) per pineapple strain fragment. Thus, the production of two types of pineapple strains, young and old strains (The young strains bear green leaves and make up all the strains that have produced fruit. Their ages range from 0 to 12 months after the fruit has been harvested. The old strains without green leaves are older than 12 months of age), was evaluated on three types of substrates, namely : S1, 100% coarse coconut fibre; S2, 2/3 coarse coconut fibre + 1/3 sawdust and S3, 3/4 coarse coconut fibre + 1/4 chicken droppings. The seeding of the fragments on the substrates it's made in a completely randomized device in a greenhouse. The study carried out was repeated twice during the same period. Results showed that vivo plant production varied according to the age of the pineapple strain. With fragments of young strains, a mean of 3.96 ±1.74 (average ± Ecart-type) vivo plants per fragment was obtained compared to 3.07±1.63 (average ± Ecart-type) vivo plants at fragments of old strains. This difference was significant with P = 0.000. The effect of substrate was significant on the number of plants produced per strain fragment. More plants per fragment were obtained on S2 with 3.53±1.1 (average ± Ecart-type) vivo plants than on the other substrate types S1 and S3 with 3.22±1.3 and 3.09±1.02 (average ± Ecart-type) vivo plants per strain fragment, respectively. This difference was significant with P= 0.002. This study showed that a strain fragment after fragmentation gives only 3.96 ± 1.74 plants in six months. This production of pineapple vivo plants is influenced by the type of substrate and the age of the strain. Thus, young strains grown on a substrate that maintains moisture should be recommended for sustainable production of pineapple vivo plants.

The tomato crop is confronted to numerous soilborne pathogens, including Ralstonia solanacearum, which considerably limits its production. In order to control this bacterium, a biological control approach has been considered by evaluating the efficacy of the NECO biopesticide against this bacteriosis. In vitro confrontations were carried out using a range of five concentrations of the biopesticide. In vivo, NECO solutions of 5 and 10 mL/L were incorporated into soil previously infested with R. solanacearum before transplanting tomato plants. Zones of bacterial growth inhibition were observed after the application of the NECO biopesticide. Results showed that the 20 mL/L concentration resulted in a higher inhibition rate. The biopesticide at the 10 mL/L concentration significantly reduced the incidence of bacterial wilt (54.05%) under in vivo conditions. The NECO biopesticide could be used as a control agent for Ralstonia solanacearum.

The sugarcane smut disease caused by Sporisorium scitamineum occurs in all production areas. In order to contribute to the management of this disease, a study was carried out in vitro conditions. The aim of this study was to evaluate the antifungal efficacy and to determine the inhibitory concentration of the essentials oils of Ocimum gratissimum, Zingiber officinale and Cymbopogon citratus upon two strains B and Z of Sporisorium scitamineum. These oils were tested on mycelial growth of colonies, spores’ production and teliospores germination. The results showed a variable fungitoxic effect of the oils according to doses. Mycelial growth and spores production were totally inhibited (100%) from 1000 ppm by all the oils. The 90% inhibitory concentrations (IC90) obtained were 880.37 ppm, 847.83 ppm and 805.75 ppm for Ocimum gratissimum, Zingiber officinale and Cymbopogon citratus, respectively. The germination of teliospores was completely reduced by the three essential oils from 500 ppm upwards. Propiconazole had strong inhibitory effects at 400 ppm with a very low IC50 and the IC90 ranged from 305 ppm to 323.36 ppm. Moreover, at the level of the strains, no difference in resistance was observed These oils could provide a good means of controlling sugarcane smut.

In Africa, cereals are major staple foods for the majority of the population. The cereal crop is not immune to the problem of salinity, which could threaten 10% of its world harvest. This work was undertaken to study the comparative effect of salinity on germination of three cereals, maize (Zea mays), millet (Pennisetum glaucum) and rice (Oriza sativa). The seeds were germinated in Petri dishes containing a range of NaCl solution (0 g/l, 5 g/l, 10 g/l, 15 g/l and 25 g/l) in the dark and at room temperature. The harmful effect of salt varies depending on the concentration of NaCl and the type of cereal. It is low on the germination rate of seeds up to a concentration of 10 g/l NaCl. From this dose onwards, this rate is reduced by 44% for millet, 20% for rice and 10% for maize. The average germination time between 0 g/l and 10 g/l NaCl is low and increases strongly between 10 g/l and 15 g/l and reaches 37 days (millet) and 20 days (rice). Corn root growth is less affected by salinity (1.2 cm) at 15 g/l NaCl compared to more sensitive rice and millet (0 cm). The height of the epicotyl between 0 g/l and 25 g/l NaCl increased from 11.8 to 3.6 cm (corn), from 0.5 to 0 cm (rice) and from 4.3 to 0.3 cm (millet). The combination of the parameters studied shows that all three cereals are able to tolerate NaCl concentrations of 10 g/l. Rice is the most sensitive to salinity while maize is more tolerant than millet.

The tomato (Solanum lycopersicum L.) is a fruit vegetable that is widely consumed in Ivory Coast. However, its production is severely limited by Blossom-end rot, one of the most constraining abiotic diseases of tomato cultivation in some production areas of the country. The present work was initiated to evaluate the effectiveness of the physio-activator "Folical", based on algae extract (Ascophyllum nodosum), which is composed of GA 14 and 202.5 g/L of calcium oxide, in the treatment of Blossom-end rot of tomatoes. To achieve this objective, a trial was carried out on soil potentially deficient in calcium and magnesium. The optimal dose of Folical for efficient reduction of Blossom-end rot incidence was determined. The efficacy of this dose was compared with that of two reference products. The doses of Folical 4 L/ha, 5 L/ha and 6 L/ha as well as the recommended doses (0.25 L/ha and 109.4 Kg/ha) and tap water (product-free controls) were applied by foliar spraying in a completely randomized Fisher block system with three replicates. The doses of Folical had significant effects on reducing the rate of attacked plants and Blossom-end rot fruits. The rates of 5 L/ha and 6 L/ha, which gave the lowest rates of attacked plants, 29.36% and 37.42% respectively, also resulted in a reduction in the incidence of Blossom-end rot fruits in treated plants, which were 4.85% and 5.47% respectively, compared to the reference products; Codamin (8.4%) and Calcium Nitrate (13.78%), and the untreated control (27.48%). The 5 L/ha dose of Folical recorded the lowest fruit growth rate of 6.42% and the average weight of the highest fruit was 94.8 g.The doses of 5 L/ha and 6 L/ha of bio activator were the most effective in the treatment of tomato Blossom-end rot.

Cassava virus causes huge yield losses in cassava cultivation in West Africa and especially in C��te d'Ivoire. However, according to prior research, little work has been done for effective curative control against the ACMV. Our study aims to propose methods of fight against the responsible vector of the incidences. Test were conducted in both controlled area and in a peasant area with stark virucide and Herbagreen bio-fertilizer at different concentrations to evaluate their effects on the growth and development of plants affected by the disease. The results of this work showed that ACMV is a disease that affects the growth and development of affected plants. The Herbagreen bio-fertilizer favored the growth and development of the affected plants and the virucide STARK permanently canceled the degree of severity of the disease during the experimentation time. In view of these results, stark virucide and Herbagreen bio-fertilizer can be used to foster the growth and development of cassava plants with ACMV., Journal of Analytical Sciences and Applied Biotechnology, Vol. 3, No 2 (2021): July - December (In progress)

In Côte d’Ivoire, palm oil occupies a preponderant position in agricultural production, in the economy, as well as consumer fats. Yield remains low, even with improved plant material being popularized whose productivity is estimated at more than 25 tons/ha/year. Trials have been set up in La Mé and Ehania (South-east Côte d’Ivoire), to help improve oil palm productivity, through a comparative study of the efficiency of potassium fertilization applied according to the locality. The experiments were conducted in Fisher blocks, including 5 treatments and 4 repetitions. The treatments included 5 doses of potassium fertilizer (T1, T2, T3, T4, T5) corresponding, respectively, to 1; 1.5; 2; 2.5; 3 kg KCl/tree/year. The results showed that the rainfall recorded in the locality of Ehania was significantly higher than that of La Mé. The average annual rainfall was 2000 mm of water in Ehania against, approximately, 1700 mm of water in La Mé. The yield and its components (weight of the bunch and number of bunches) were gradually improved according to the locality of cultivation by the different doses of fertilizer applied. This improvement was significantly higher on the Ehania plantation compared to that of La Mé. This improvement was approximately 30% and 27% compared to the standard dose of 1 kg KCl/tree/year, respectively, in Ehania and La Mé. It appears that the locality intervenes in the efficiency of potassium fertilizers, in the improvement of yield and its components. Rainfall appears, as, a main factor of productivity observed on the plot of the oil palm. Strict compliance with the choices of suitable areas, combined with reasoned potassium fertilization, will allow a better expression of the production potential of new oil palm plant material, currently being popularized.

Aims: Banana and plantain contribute to food security in Côte d'Ivoire. However, one of the major difficulties arising in its production remains parasitic constraints causing the loss of production. Among these constraints, leaf diseases cause more damage. Methodology: This study was initiated to analyse the nature of host-pathogen interactions (resistance or sensitivity) between the fungus Deightoniella torulosa and certain varieties of banana and plantain in Côte d'Ivoire. The pathogenicity of the fungus was measured from artificial inoculation on leaf fragments that were kept alive on a specific culture medium in Petri dishes. This medium consisted of agar amended with Benzimidazole. Leaf’ fragments that survived inoculation of spore suspensions, exhibited the characteristic symptoms of the fungus Deightoniella torulosa. The impact of the fungus on the degradation of chlorophyll was noted. Results: The results showed that the strains of Deightoniella torulosa have a pathogenic activity on the banana trees. The concentration of 75 μM of Benzimidazole incorporated into the survival medium can be used for inoculation tests on leaf fragments. Conclusion: The Grande Naine cultivar could be used as a control indicator for D. torulosa.

This study aims at assessing the in vitro activity of Cymbopogon citratus, Eucalyptus citriodora, Lippia multiflora, Melaleuca quinquenervia essential oils and the biobactericide Neco® on extended-spectrum β-lactamases producing or non-producing bacterial strains (ESBL) isolated at the Armed forces hospital of Libreville. The aromatogram and antibiogram were respectively assessed by the agar well diffusion method and agar disc method. Thus, the minimum inhibitory concentration and minimum bactericidal concentration were determined by the microdilution method in liquid medium. The aromatogram revealed that the biobactericide Neco® induced the largest inhibition diameters (28.42 - 43.27 mm) in all strains, followed by E. citriodora (26.96 - 36.12 mm) and L. multiflora (15.32 - 41.42 mm) essential oils. In contrast, M. quinquenervia (9.83 - 26.64 mm) and C. citratus (6.82 - 14.97 mm) essential oils had the smallest inhibition diameters. Furthermore, the comparison of aromatogram and antibiogram activities generally revealed that activities are better with essential oils than with antibiotics. In addition, no significant differences were observed between ESBL producing or non-producing strains. At the end this study, the antibacterial activity of C. citratus, E. citriodora, L. multiflora, M. quinquenervia essential oils and the biobactericide Neco® were highlighted. However, the efficiency of these activities is dependent on the intrinsic composition of the plant. Key words: Essential oils, extended spectrum β-lactamase (ESBL), multi-resistance, biobactericide, antibacterial activity.

Black Leaf Streak Disease (BLSD) is the most restricting leaf disease to banana tree cultivation around the world. In order to control this disease, synthetic fungicides are extensively used. However, these products pose a real danger to environmental pollution and the health of applicators and consumers. Faced with this situation, alternative solutions must be considered to overcome their systematic use. This study was initiated in this context so as to assess the effectiveness of 20 biopesticide formulations on Mycosphaerella fijiensis conidia stemming from banana tree leaf samples originating from village plantations and showing the typical symptoms of stage 2 or 3 black Sigatoka. The assessment method used was that of dispersion in solid medium. Observations were made under an optical microscope equipped with a camera and consisted in determining the inhibition rates of conidia germ tube growth. A pathogenicity test was performed with 8 Mycosphaerella spp. isolates according to an inoculation technique under controlled conditions on whole plants of 5 banana tree cultivar vivoplants. The assessment of biopesticide protection effectiveness against BLSD was conducted on cultivar "Orishele" (very susceptible) with the most aggressive and virulent strain selected during isolate pathogenicity test. The results obtained show that all biopesticide formulations have significant antifungal activity on M. fijiensis conidia germ tube elongation. The average inhibition rate ranged from 83.31 to 99.89% for all biopesticides. The 8 M. fijiensis isolates used have all raised symptoms characteristic of black leaf streak disease regardless of the cultivar. In contrast, no isolate caused symptoms characteristic of Sigatoka disease (Yellow Sigatoka). Biopesticides and synthetic fungicides significantly reduced disease development rate compared to inoculated and untreated controls, but at varying degrees. Preventive treatment of seedlings is found to be much more effective than curative treatment. However, in order to protect banana and plantain tree varieties against M. fijiensis, both types of treatments are necessary.

In a world where new technologies are being developed at a dizzying pace, how can we best approach oral genres that represent heritage? Taking an innovative and interdisciplinary approach, this volume explores the idea of sharing as a model to construct and disseminate the knowledge of literary heritage with the people who are represented by and in it. Expert contributors interweave sociological analysis with an appraisal of the transformative impact of technology on literary and cultural production. Does technology restrict, constraining the experience of an oral performance, or does it afford new openings for different aesthetic experiences? Topics explored include the Mara Cultural Heritage Digital Library, the preservation of Ewe heritage material, new eresources for texts in Manding languages, and the possibilities of technauriture. This timely and necessary collection also examines to what extent digital documents can be and have been institutionalised in archives and museums, how digital heritage can remain free from co-option by hegemonic groups, and the roles that exist for community voices. A valuable contributi on to a fast-developing field, this book is required reading for scholars and students in the fields of heritage, anthropology, linguistics, history and the emerging disciplines of multi-media documentation and analysis, as well as those working in the field of literature, folklore, and African studies. It is also important reading for museum and archive curators.

Introduction This chapter expands the documentation of a video recording of the song “Nanyuman” by Mali’s legendary female bard Siramori [Sira Mory] Diabaté (ca. 1925–1989). This unique recording was recently collected in the archives of Radio Télévision Guinéenne (RTG), and was then made available on YouTube. This paper adds a transcription and translation to Siramori’s version of “Nanyuman”, and this enhancing of the YouTube video is an attempt to produce a teaching tool. This contribution ...

Salicylic acid and its analogues are considered the most important compounds which can be activated a systemic acquired resistance (SAR) in plants. The disadvantages and limits related to the usual methods in particular fungicide spray to the control of black leaf streak disease (BLSD) require research of approaches more respectful of the environment for this disease management such as the use of SAR inducers. The effects of Salicylic acid (SA) and Acibenzolar-S-methyl (ASM) on the interaction of two susceptible cultivars of banana (Orishele and Corne 1) with the hemibiotrophic fungal Mycosphaerella fijiensis and his toxin (juglone) were investigated. The results showed that SA and ASM at low concentrations (25 and 50 µg/ml) did not affect M. fijiensis development but have the capacity to induce protection into sensitive banana against juglone toxic effect. These SAR inducers reduced the intensity of the necrosis due to the juglone and lengthened the incubation period of M. fijiensis after inoculation of banana leaves. The expression of the resistance induced was related to the variety of banana. More significant effectiveness of protection was obtained with ASM in particular on Corne 1. A total protection against the induction of necrosis was kept up to 100 µg/ml of juglone 2 to 3 weeks after application of ASM on the soil and on the leaves of banana. ASM constitutes a viable and noncontaminant option in the fight against to BLSD because of his non-inhibiting action on M. fijiensis and excellent protection into banana when roots and leaves were treated.