Aims: The present investigations describes bactericidal potential of essential oil for management of Xanthomonas albilineans (Ashby. 1929) Dowson 1943, pathogen responsible for sugarcane Leaf scald disease in Côte d'Ivoire. Study Design: the study was conducted at the Ferké 1 sugar mill and the Laboratory of Plant Physiology of Felix Houphouët BOIGNY University. Methodology: Diseased leaves specimens showing signs of X. albilineans presence were collected from sugarcane industrial plantations in Côte d'Ivoire. Pathogenicity was confirmed by observing Koch’s postulates under semi-controlled conditions. Asymptomatic leaves, obtained after 60 days of culture, were inoculated at three points by infiltration with bacterial suspension calibrated at 108 bacteria/ml. Apparition of small tan-brown necrotic lesions on the leaf blade, parallel to the veins and prolonged to the ends by a discolored vascular bundle confirmed that disease is caused by Xanthomonas albilineans. Three essential oils of aromatic plants whose antibacterial properties are recognized were used at 100; 300; 500; 1000 and 2000 ppm in comparison with Callicuivre (56% copper oxychloride) used as reference product. Results: The aqueous solutions based on these essential oils induced an inhibition zone of bacterial growth proportional to the dose applied and the incubation period. Thus, on day 5 of incubation, the essential oil solution of Ocimum gratissimum L. at 100 ppm induced an average inhibition zone diameter not significantly different from the one induced by the Cymbopogon citratus (DC.) Stapf solution at 300 ppm and the one of copper oxychloride at 1000 ppm. At 1000 ppm, Zingiber officinale Roscoe, Cymbopogon citratus (DC.) Stapf and Ocimum gratissimum L essential oils induced equivalent inhibition rates (6 mm) that were higher than that of the control (3.5 mm). Conclusion: sugarcane varieties cultivated at the Ferké 1 sugar mill complex, despite the selection for resistance are threatened by Leaf Scald Disease, which is significantly expressed on variety R585. Cymbopogon citratus (DC.) Stapf and Ocimum gratissimum L oils have the strongest antibacterial activity and may be useful to control Leaf Scald Disease.

Les  fruits  et les légumes  tropicaux présentent  la  particularité  d'être sensibles  au  froid.  Ainsi,  les  basses températures  ne  peuvent  pas  être utilisées  pour  allonger  leur  durée  de vie verte. Pour juguler ces effets, l’utilisation de produit d’enrobage est une pratique courante tout en respectant les exigences environnementales et humaines. C’est dans ce contexte d’amélioration de la qualité des fruits à l’export et d’assurer la sécurité des consommateurs, que cette expérimentation a été initiée. L’objectif de l’étude était d’évaluer l’efficacité de plusieurs doses, d’une cire à base d’huiles végétales : Colza + olive 100 g/l (AgroSfruits TM 100 EO) en comparaison à un produit de référence DECCO LUSTR 444 (Acide oléique < 5 % + Propylène Glycol < 50 % + Sorbitan monostéarate éthoxylé 10-40 %) pour une meilleure conservation post-récolte des ananas lors de l’exportation. Cinq (5) traitements (T0, T1, T2, T3, T4) ont été évalués au cours de cette expérience. Chaque traitement a reçu 35 ml de Scholar et une quantité de 100 à 200 g d’acide citrique avec un pH ajusté à 5. Aux traitements T1, T2 et T3, il a été ajouté respectivement 67,17 ; 64,37 et 61,57 l d’eau et une quantité respective de 2,8 ; 5,6 et 8,4 l de AgroSfruits TM. Au T4, il a été ajouté 64,37 l d’eau et 5,6 l DECCO LUSTR 444. Les pourcentages de dilution des traitements T1, T2, T3 et T4 sont 4 %, 8 %, 12 % et 8 % respectivement. Les résultats obtenus  montrent que la perte de masse chez les fruits traités au T2 a été moindre,  soit 347 g. Les fruits de coloration M2, après 14 jours de stockage au froid pour le T1, ont présenté la meilleure fermeté, soit 5,5 g/cm2. Les traitements T0, T1, T2, et T3 ont eu des niveaux d’acidité titrable élevé et statistiquement identique avec respectivement 17,52 ; 18 ; 17,61 et 16,83 meq/100 ml de jus d’ananas.   Tropical fruits and vegetables have the particularity of being sensitive to cold.  Thus, low temperatures cannot be used to extend their green life. To curb these effects, the use of coating product is a common practice while respecting the environmental and human requirements. It is in this context of improving the quality of fruit for export and ensuring consumer safety that this experiment was initiated. The objective of the study was to evaluate the effectiveness of several doses of a wax based on vegetable oils: Rapeseed + olive 100 g / l (AgroSfruits TM 100 EO) compared to a reference product DECCO LUSTR 444 (Oleic acid < 5% + Propylene Glycol < 50% + Ethoxylated Sorbitan monostearate 10-40%) for a better post-harvest preservation of pineapples during export. Five (5) treatments (T0, T1, T2, T3, T4) were evaluated in this experiment. Each treatment received 35 ml of Scholar and 100 to 200 g of citric acid with pH adjusted to 5. In treatments T1, T2 and T3, 67.17; 64.37 and 61.57 l of water and 2.8; 5.6 and 8.4 l of AgroSfruits TM were added, respectively. In T4, 64.37 l of water and 5.6 l of DECCO LUSTR 444 were added. The dilution percentages of treatments T1, T2, T3 and T4 are 4%, 8%, 12% and 8% respectively. The results obtained show that the loss of mass in the fruits treated in T2 was less, 347 g. Fruits with M2 coloration, after 14 days of cold storage for T1, showed the best firmness, 5.5 g/cm2. Treatments T0, T1, T2, and T3 had high and statistically identical titratable acidity levels with 17.52; 18; 17.61 and 16.83 meq/100 ml of pineapple juice, respectively.

In the southeastern of Côte d'Ivoire, ferralsols are characterized by poverty in exchangeable bases, especially potassium, which appears to be the predominant mineral element for oil palm cultivation.   In this study, we used improved palm cultivars treated with different rates of potassium fertilizer to determin the effect on oil palms. The experiments were conducted on the CNRA station in La Mé and PALMCI in Ehania (Côte d’Ivoire), following a system block system design comprising of five treatments and four repetitions. Treatments included 5 rates of potassium fertilizer (T1, T2, T3, T4, T5) corresponding to 1; 1.5; 2; 2.5; 3 kg of KCl/tree/year. This study indicates that the different rates of KCl applied, had influence on    all of the experimental parameters, namely: yields (TR) and its components (NR; PR and PMR). Yields on the Ehania plantation were significantly higher than those on La Mé. Yield ranged from 18.8 Tons/ha/year (T1) to 22.1 Tons/ha/year (T3) in La Mé, and from 21.2 to 25.6 tons/ha/year in Ehania. The theoretical maximum rates were 2.4 kg of KCl/tree/year in La Mé, compared to 1.9 kg/tree/year on the Ehania plantation. Therefore, these rates will be used in the future extension of potassium fertilizer, in the cultivation of oil palm, in the southeastern of Côte d'Ivoire.

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.

Black leaf streak disease (BLSD) caused by Mycosphaerella fijiensisa an ascomycete fungus is the most important foliar disease ofbananas (Musa sp.). Losses due to this pathogen can exceed 50% in case of no resistant cultivars and effective treatments. This study aimed to evaluate the efficacy of four biopesticides on the severity of Mycosphaerella fijiensis. It was conducted under natural infestation conditions in the industrial dessert banana plantation of the Agricultural Company KablanJoublin (SAKJ) at Elima (Aboisso). To make it possible some phytopathological, growth and agronomic parameters of banana plants were evaluated. The results showed that banana trees of plots treated with biopesticides had identical characteristics, about all the assessed parameters, with those of plots treated with the chemical fungicide. In addition, applications of biofungicide contributed to protecting banana leaves, slowed down the onset of necrotic first stage and significantly reduced the disease infestation level in the parcels. The use of aromatic plant essential oils-based biofungicides could be suggested as an ecological efficient solution to dessert banana and plantain producers against Mycosphaerella fijiensis responsible for the black leaf streak disease.