Evaluation De La Production De Cinq Genotypes De Palmier A Huile (Elaeis Guinnensis Jacq.) Replantes Sur Des Parcelles A Haute Densite De Fusariose

Fusarium wilt is the most serious disease of the oil palm (Elaeis guineensis Jacq.) In Africa. The methods of fighting this disease are mainly based on the search for tolerant plant material, so the researchers of CNRA were able to make available to the producers of the genotypes tolerant to the Fusarium wilt. However, two of these supposedly tolerant genotypes, planted on plot D9-3 in Ehania, a highly endemic plot, showed symptoms of vascular Fusarium wilt after 9 years of replanting. The evaluation of production responses in comparison with the physiological states of other genotypes of the same parental origin showed that the LM25373 and LM25635 progenies retained their ability to produce in spite of their doubtful physiological state. The appearance of the external symptoms of FHB did not affect the cycles of production of these so-called diseased progeny

Foliar Application of Boron during Flowering Promotes Tolerance to Cocoa (Theobroma cacao L.) Swollen Shoot Viral Disease

Boron nutrition is known to reduce the effect of some viral and fungal diseases on plant fitness. This study investigated the potential of boron application to improve yield and tolerance of cacao trees naturally infected by virulent cocoa swollen shoot virus (CSSV) strains and determined the effective dose and time of application. Foliar sprays of a commercial product containing 20.5% of boron were performed either at the onset of flowering’s peak of the little milking (early in November) or four weeks later (early in December) with four doses of boron (0, 31.25, 41.67, and 83.27 g/ha) in a randomized complete block design with four replications. We found that boron application improved foliar density and induced production of pods of normal shape meanwhile reducing the appearance of this misshapenness due to CSSV. Boron also increased the number of emitted flowers, cherelles and pods subsequently. Moreover, weight and size of fresh cocoa beans per pod were positively correlated to boron dosage. Interestingly, foliar sprays performed early in November resulted in less flat cocoa beans. Finally, the optimal dose of boron that reduced the adverse effects of the most virulent form of cocoa swollen shoot viral disease is 41.67 g/ha

The Yaya Reserve: From the Evolution of its Plant Cover to Proposals for Sustainable Management

The Yaya reserve, one of the biodiverse forests in Ivory Coast, faces significant threats from agricultural colonization, illegal logging, and demographic pressure, which could jeopardize its sustainability. This paper focuses on contributing to the reserve’s sustainable management. To achieve this, three categories of data were collected: remote sensing data, floristic inventory data, and survey data from the neighboring populations. Remote sensing data were obtained by downloading images from the USGS earth explorer website. Floristic data were obtained through surface and itinerant survey. Survey data were collected using a structured interview. The images were processed to calculate the areas of various land use classes. The floristic data were analyzed for species richness and composition, while the survey data were analyzed to understand local perceptions of landscape dynamics, current management practices, and proposals for participatory management. The results revealed two major periods in the forest’s dynamics: increased deforestation from 1986 to 2005 and subsequent restoration from 2005 to 2022. These phases of degradation and restoration are likely related to recent social and political crises and management challenges. The floristic inventory identified 167 woody species across 134 genera and 47 families. 24 species (14% of the total) are endemic to West Africa, and 21 species (12.42%) are listed on the IUCN red list, indicating a relatively good conservation of the forest. The survey data highlighted the vulnerability of the forest and underscored the importance of centralized decision-making in management. The study suggests that participatory management could be a viable alternative for protecting the reserve. The hypotheses clearly states that the active involvement of local populations in the sustainable exploitation of forest resources can improve living standards, while helping to preserve the forest from exploitative practices

Inventaire Des Champignons Pathogènes Post-Récolte De La Banane Dessert « Cavendish » Et Evaluation De Leur Sensibilité A l’Azoxystrobine En Côte d’Ivoire

This study was aimed at drawing up an inventory of the post-harvest pathogenic fungi of banana dessert and to assess their susceptibility to Azoxystrobin. A sampling was carried out in banana fruit processing factories of the main Ivorian zones of banana production (Niéky, AboissoAyamé-Akressi and Tiassalé). The identification and frequency of isolation of the fungal species associated with the affected parts of the fruit was based on their cultural aspects, reproductive structures and percentage of contamination. The susceptibility of post-harvest fungi to different doses of Azoxystrobin 3.5, 4 and 4.5 g/hl was compared to a reference product, Bitertanol at a dose of 2 g/hl and to a check where only water is applied. Of the 13 pathogenic fungal species isolated, Botryodiplodia theobromae was the most recurrent and was identified as the main causal agent of postharvest rots. It is followed by Colletotrichum musae, Aspergillus niger, Fusarium moniliforme, Geotrichum candidum, Fusarium semitectum and Aspergillus flavus, in which the isolation frequencies are significantly different. The results on the susceptibility of pathogenic fungi to Azoxystrobin show that the three doses of Azoxystrobin have significantly different effects from that of the reference product and the check. They reduce infection rates up to 91.67% and give a high proportion of marketable fruits, respectively. Surprisingly, the dose of the reference product gives a low rate of reduction of infections (49%) and a proportion of marketable fruit that is significantly identical to that of water treatment

EXPERIMENTAL ANALYSIS OF THE MECHANICAL BEHAVIOR OF CLAY-CEMENT BLOCKS REINFORCED WITH COCONUT FIBERS

This article aims for analyzing under an axial stress, the behavior of earth blocks reinforced by various proportions of coconut fibers. For this fact, compressive and flexural tests were carried out after 28 days of maturation, on dry blocks elaborate with clay stabilized at 8% of cement and containing 0 to 1% of fibers 30 mm length. The experimental results show that the incorporation of fibers in the blocks improves their mechanical characteristics, increases their ductile deformation and delays their cracking. The best mechanical resistances are obtained at 0.8% of fibers because at this content, the distance between fibers is optimal

Latex micro diagnosis, modern management tool of rubber plantations of clones with moderate metabolism GT 1, RRIC 100 and BPM 24

Objective: The cultivated rubber clones are sensitive to latex harvesting regimes according to their laticiferous metabolism. This study was done to determine the best latex harvesting system (s) of clones with moderate metabolism (GT 1, RRIC 100 and BPM 24).Methodology and Results: Six latex harvesting technologies were  applied to these clones in a bulk statistical device from Fisher to four rehearsals. The rubber trees were tapped in downward half spiral stimulated or not, for nine years after the opening of the tapping panel. The agronomic parameters (latex production, vegetative growth), the tapping panel dryness and those of the latex micro diagnosis were  evaluated. The results indicate that these clones independently of the latex harvesting system have good rubber productivity (2234 kg.ha-1.y-1) with good radial vegetative growth (2.4 cm.y-1). Their trees showed a well-balanced physiological profile and an acceptable sensitivity to the tapping panel dryness (3.2 %). However, the physiological index, the bark consumption and the sensitivity to the tapping panel dryness lead to retain the latex harvesting technology "S/2 d4 6d/7 Pa1 (1) ET2.5% 4/y” for the best.Conclusion and application of results: This index, favourably  influencing the choice of technologies adapted to clones with active metabolism, contributes to the modern and efficient management of a rubber plantation.Key words: latex-harvesting technology, rubber clones, moderate  metabolism, tapping panel dryness, physiological parameter

Latex Micro Diagnosis, Modern Management Tool of Rubber Plantations of Clones With Active or Rapid Metabolism IRCA 18, IRCA 130, PB 235, PB 260 and PB 330

The cultivated rubber clones are sensitive to latex harvesting regimes according to their laticiferous metabolism. Thus, in order to determine the best latex harvesting systems of clones with active or rapid metabolism (IRCA 18, IRCA 130, PB 235, PB 260 and PB 330), six latex harvesting technologies are applied to them in a bulk statistical device from Fisher to four rehearsals. The rubber is tapped in downward half spiral stimulated or not for nine years after the opening of the tapping panel. The agronomic parameters (production, vegetative growth), the tapping panel dryness and those of the latex micro diagnosis were evaluated. The results indicate that these clones independently of the latex harvesting system have good rubber productivity (2310 kg.ha -1.y1) with good radial vegetative growth (2.9 cm.y-1). Their trees show a wellbalanced physiological profile and an acceptable sensitivity to the tapping panel dryness (4.9%). However, the physiological index, the bark consumption and the sensitivity to the tapping panel dryness lead to retain the latex harvesting technologies “ S/2 d3 6d/7 Pa1(1) ET2.5% 4/y and S/2 d4 6d/7 Pa1(1) ET2.5% 4/y ” for the best. This index, favorably influencing the choice of technologies adapted to clones with active metabolism, contributes to the modern and efficient management of a rubber plantation

Contribution of Latex Micro Diagnosis to Modern Management of Rubber Plantations: Case of Clones With Low or Slow Metabolism PB 217 and PR 107

The cultivated rubber clones are sensitive to latex harvesting regimes according to their laticiferous metabolism. Thus, in order to determine the best latex harvesting systems of clones with low or slow metabolism, six latex harvesting technologies are applied to them in a bulk statistical device from Fisher to four rehearsals. The rubber is tapped in downward half spiral stimulated or not for nine years after the opening of the tapping panel. The agronomic parameters (production, vegetative growth), the tapping panel dryness and those of the latex micro diagnosis were evaluated. The results indicate that these clones independently of the latex harvesting system have good rubber productivity (2310 kg.ha -1 .y-1 ) with good radial vegetative growth (2.9 cm.y -1 ). Their trees show a well-balanced physiological profile and an acceptable sensitivity to the tapping panel dryness (4.9%). However, the physiological index, the bark consumption and the sensitivity to the tapping panel dryness lead to retain the latex harvesting technologies "S/2 d3 6d/7 Pa1(1) ET2.5% 4/y, S/2 d4 6d/7 Pa1(1) ET2.5% 4/y and S/2 d4 6d/7 Pa1(1) ET2.5% 8/y” for the best. This index, favorably influencing the choice of technologies adapted to clones with active metabolism, contributes to the modern and efficient management of a rubber plantation

Contribution à la Gestion des Cercosporioses du bananier dues à Mycosphaerella spp. par l’utilisation du Fluopyram associé à l’huile minérale en Côte d’Ivoire

Objectifs : En vue de contribuer à la gestion des cercosporioses du bananier, un essai a consisté à comparer l’efficacité biologique du Fluopyram (500g/l) associé à un émulsifiant mouillable à l’eau et sa suspension dans l’huile. Le but de cet essai est de trouver les mélanges qui donnent une efficacité maximale au produit pour lutter efficacement contre les cercosporioses du bananier. Il s’agit de Fluopyram + eau + émulsifiant, Fluopyram + huile +émulsifiant + eau et enfin de Fluopyram + Huile + eau.Méthodologie : Le dispositif expérimental choisi est en blocs aléatoires complets (ou blocs de Fisher) avec 7 objets et 3 répétitions. Chaque parcelle élémentaire comportait 6 bananiers qui sont traités, mais les observations ont été portées sur 4 bananiers compte tenu des effets de bordure, soit 12 bananiers à observer sur 18 à traiter par objet. Les applications de fongicides ont été effectuées avec un atomiseur sur le feuillage et le pseudo-tronc des bananiers. Des observations hebdomadaires ont été faites sur les paramètres épidémiologiques et de croissance du bananier. Ces paramètres ont permis de calculer l’état d’évolution de la maladie après chaque traitement.Résultats et Applications : Les mélanges Fluopyram + huile + émulsifiant + eau et Fluopyram + huile + eau sont très efficaces comme leurs références respectives. A partir de la quatrième semaine leurs effets se renforcent. Le mélange Fluopyram + eau + émulsifiant contrôle partiellement la maladie. Les traitements avec de l’huile prolongent la période d’incubation des ascospores et retardent la formation des premiers stades de la maladie (en tirets). Pour le traitement au Fluopyram + eau + émulsifiant, les fréquences d’application devraient être rapprochées pour qu’il y ait un meilleur contrôle de la maladie. Ce résultat devrait être pris en compte dans une gestion intégrée contre les cercoporioses du bananier.Mots clés : efficacité, fongicide, bananier, cercosporioses, émulsifiant, huil