La production du riz au Burkina Faso est limitée par certaines maladies fongiques transmises par les espèces du genre Fusarium. A cet effet, l’importance de ces champignons a été évaluée sur 59 échantillons provenant de 7 variétés de riz par la méthode du papier buvard. Les sites sont répartis dans les 13 régions administratives situées en fonction des 3 zones agroécologiques du pays. Fusarium spp. a été identifié dans 81,35% des échantillons à des taux d’infection de 1 à 41%. Fusarium spp. est présent dans toutes les zones agroécologiques avec des taux de prévalence variant de 78,2 à 83,87%. Les échantillons provenant de la zone Soudano-Sahélienne et Soudanienne ont été plus infectés (respectivement 6,74% et 5,34%) que ceux de la zone Sahélienne (1,40%). Ces champignons ont été rencontrés dans toutes les régions du pays avec des taux d’infections de semences variant de 0,5 à 15,25%. Les régions les plus attaquées étant le Centre-Sud (15,25%), le Centre (11,75%) et la Boucle du Mouhoun (11,5%). L’étude montre un taux d’infection global des semences par Fusarium spp. de 5,74%. Une identification des espèces rencontrées sur le riz est impérative. L’évaluation de leur pathogénicité permettra de déterminer celles impliquées dans le gigantisme du riz. Mots clés : Fusarium spp., prévalence, taux d’infection, semences de riz Incidence of Fusarium spp. associated with rice seeds (Oryzae sativa L.) in Burkina Faso Rice production in Burkina Faso is limited by some fungal diseases transmitted by species from the genus Fusarium. To this end, the importance of these fungi was assessed on 59 samples from 7 rice varieties using the blotting paper method. The sites were distributed in the 13 administrative regions located according to the 3 agro-ecological zones of the country. Fusarium spp. was identified in 81.35% of the samples at infection rates ranging from 1 to 41%. Fusarium spp. is present in all agroecological zones with prevalence rates ranging from 78.2 to 83.87 %. Samples from the Sudano-Sahelian and Sudanian zones were more infected (6.74% and 5.34% respectively) than those from the Sahelian zone (1.40%). These fungi were found in all regions of the country with seed infection rates ranging from 0.5 to 15.25%. The most affected regions were the Centre-South (15.25%), the Centre (11.75 %) and the “Boucle du Mouhoun” (11.5%). The study shows an overall seed infection rate of Fusarium spp. of 5.74%. Identification of the species found on rice is imperative. Evaluation of their pathogenicity will make it possible to determine which species are involved in the rice's gigantism.Keywords: Fusarium spp., prevalence, infection rate, rice seed

Soybean is one of the promising food crops and feeds which contributes significantly to the development of agriculture in Burkina Faso. However, very few improved soybean varieties have been developed in the country. The introduction of new genotypes with high agronomic potential and adapted to the climatic conditions of the Sudanian zone of Burkina Faso will boost soybean production in the region. Twenty-four (24) newly introduced soybean genotypes were evaluated for their agromorphological and adaptation characteristics in the Sudanian zone of Burkina Faso. The variability parameters such as genotypic and phenotypic coefficient of variation, broad sense heritability, and expected genetic advance were estimated for 14 agromorphological characters. The experimental design used in this study was an alpha lattice with 3 replications. Planting was done following a spacing of 50 cm (inter-row) × 5 cm (within row). Analysis of variance revealed significant difference ( P < 0.001 ; P < 0.05 ) for all characters studied except the nodule diameter, nodule score, and grain yield. The values of the phenotypic coefficient of variation (PCV) were higher than genotypic coefficient of variation (GCV) for all the characters indicating the influence of environmental factors. The highest GCV and PVC values were found in the number of nodules (70.07% and 77.26%), number of seeds per plant (41.34% and 44.18%), and number of pods per plant (29.27% and 33.50%), respectively. High estimates of heritability coupled with high genetic advance expressed as a percentage of mean were observed for 10 of the 14 traits, suggesting an important expected genetic gain allowing more success in selection.

Parasitic nematodes have been reported as one of the major constraints to soybean production worldwide. The majority of nematodes are so-called "freeliving" and feed mainly on bacteria, fungi, protozoa and other nematodes. In Burkina Faso, the presence of parasitic nematodes has been reported in crops such as rice and sorghum. The objective of this study was to identify the genera and species of nematodes associated with soybean production in Burkina Faso. Investigations were carried out on 24 genotypes of a medium-maturity group of soybean at the Farako-Ba research station. Soil samples were taken from the trial soil before its installation. At harvest, soil samples with roots were taken from each genotype in the elementary plots. The composite sample is represented by 4 lots of soil samples with roots. Extractions and counts of nematodes were performed on the different lots. In total, 7 genera of plantparasitic nematodes associated with soybean were identified. Among these genera, Pratylenchus (100% of infected genotypes), Helicotylenchus (97.28%) and Scutellonema (94.44%) were the most prevalent in terms of frequency and abundance. Some soybean genotypes were less susceptible to the genus Pratylenchus is known to be highly pathogenic in soybean. These were mainly the genotypes TGX2025-10E, TGX2023-3E and TGX2025-14E.

Aims: This study was undertaken to investigate the antifungal activities of Securidaca longepedunculata and Acacia gourmaensis bark hydro-ethanolic extract against Fusarium solani, Fusarium moniliforme and Curvularia lunata and to evaluate the percentages of germination and infection of infected rice seeds. Methods: Different extract concentrations ranging from 0.25, 0.5 and 1% were tested during 15 days using poisoned food technique method for in vitro antifungal activity against above three fungal strains. The same concentrations of extract were used to evaluate in vivo antifungal activity on rice seeds infected by these three fungal strains. Results: The extract of Securidaca longepedunculata had antifungal effect on Fusarium solani and Fusarium moniliforme and completely inhibited its mycelial growth at all tested concentrations (0.25, 0.5 and 1%). Curvularia lunata mycelial growth was inhibited of 84.7% by 1% Securidaca longepedunculata extract after five days of culture. However, mycelial growth of F. solani, F. moniliforme and C. lunata were increased with increasing concentration of Acacia gourmaensis extract. It has been observed that when Securidaca longepedunculata hydro-ethanolic extract concentration increased up to 1%, seeds germination percentage decreased for all infection. In contrast, the opposite was observed for Acacia gourmaensis extract. Likewise, seeds infection decreased with the highest concentration (1%) of Securidaca longepedunculata for all infection, whereas the opposite was observed with Acacia gourmaensis extract. Conclusion: This study showed that S. longepedunculata hydro-ethanolic extract has more antifungal activity against seed-borne fungi (F. solani, F. moniliforme and C. lunata) than A. gourmaensis in vitro and in vivo. Results show that Securidaca longepedunculata hydro-ethanolic bark extract can be used as a potential antifungal agent in the management of some rice fungal diseases. Acacia gourmaensis extract, at low concentration, could be used in rice seed treatment to increase seed germination.