European Scientific Journal, ESJ

Effect of local substrates on the development of microtubers of yam (Dioscorea rotundata L.) varieties using the SAH technique

Arlette Adjatin — 2025-05-08

The inadequacy of the quantity and quality of production equipment is a major concern for yam production in Benin. Likewise, the new technique of mass production of microtubers is limited by problems related to the supply of the modern substrate. The objective of this study is to identify a local substrate based on plant residues with the potential of those imported (modern substrates) to limit their use in SAH. A control consisting of modern substrate TS3 (SM) and two substrates containing different local residues (100% carbonized peanut shell and 100% carbonized sawdust) were tested on varieties Kouna, Bobo, TDr 9519177, and TDr 8902665. A completely random two-factor bulk experimental design repeated three times was used. The plants were followed through the collection of growth data such as the plants' number, plant height, the number of branches, and the length and width, and then at the harvest, data including the number of microtubers, microtubers diameter, and weight were collected. The results obtained show that the mean of all the parameters considered for the growth and the post-harvest phase are higher with the SM substrate than those of the CA and SB substrates. In addition, discriminating parameters such as the number of microtubers, diameter of microtubers, and weight of microtubers had higher mean values (3.5; 5.37 mm; 037 g) in SB than in CA (2.08; 3.07 mm; 0.19 g), respectively. Plants seeded in the SB substrate showed significant growth gains ranging from 45 to 99% in height and from 35 to 97% in leaf width. Substrate SB, therefore, represents a good medium for the growth and production of microtubers that can replace modern substrate TS3 (SM). Nevertheless, physicochemical characterization and enrichment of the sawdust substrate should be considered to optimize the yield of yam microtubers.

Impact des Fluctuations des Prix du Pétrole et du Régime de Subventions sur la Croissance Économique au Maroc : Étude Économétrique de 1998T1 à 2022T4

Hicham Saidi — 2025-05-08

Cet article analyse l'impact des fluctuations des prix du pétrole et du régime de subventions sur la croissance économique au Maroc entre le premier trimestre de 1998 et le quatrième trimestre de 2022. En appliquant une analyse économétrique aux données trimestrielles, l’étude différencie les effets linéaires et asymétriques de prix du pétrole, ainsi que l’influence du régime de subventions. Les résultats indiquent que les hausses des prix du pétrole ( exercent un impact significatif sur la croissance du PIB, tandis que les baisses ( n'ont pas un effet direct. Le régime de subventions, quant à lui, montre un effet positif et soutenant. Ces conclusions mettent en lumière l'importance de politiques de subventions pour compenser les effets des hausses de prix du pétrole, et suggèrent d’élargir l’étude à d’autres facteurs explicatifs de la croissance économique marocaine.

This article aims to analyse the impact of oil price fluctuations and the subsidy regime on Morocco’s economic growth from the first quarter of 1998 to the fourth quarter of 2022. Through econometric analysis of quarterly data, the study distinguishes between linear and asymmetric effects of oil price changes, as well as the influence of the subsidy regime. The results indicate that increases in oil prices ( have a significant impact on GDP growth, whereas price decreases ( do not have a direct effect. The subsidy regime, on the other hand, demonstrates a positive and supportive effect. These findings underscore the importance of subsidy policies in offsetting the adverse effects of oil price increases and suggest broadening the study to other explanatory factors for Moroccan economic growth.

Etude de la co-circulation des virus Grippaux et SARSCoV-2 dans les sites sentinelles d’Infection Respiratoire Aigüe Sévère de la Grippe en République de Guinée

Mamadou Bhoye Keita — 2025-05-08

Cette étude transversale, menée du 23 juillet 2023 au 23 juillet 2024, a évalué la co-circulation des virus grippaux et du SARS-CoV-2 dans les sites sentinelles d'Infections Respiratoires Aigües Sévères (IRAS) en Guinée. Sur 639 patients inclus, 8,29 % (53 patients) étaient positifs aux virus recherchés, avec une dominance des virus grippaux (66,03 %) par rapport au SARS-CoV-2 (33,96 %). Parmi les virus grippaux, les sous-types H3N2 (77,77 % des cas de grippe A) et B Victoria (100 % des cas de grippe B) étaient les plus fréquents. La tranche d'âge des 0-2 ans était la plus touchée (54,30 % des cas), suivie des 15-50 ans (18,78 %). Aucune différence significative n'a été observée entre les sexes ou les issues d'hospitalisation. Les résultats ont révélé des périodes distinctes de circulation virale : le SARS-CoV-2 était présent presque toute l'année avec un pic en décembre 2023, tandis que les virus grippaux circulaient principalement durant les saisons pluvieuses. Des co-circulations simultanées des virus grippaux et du SARS-CoV-2 ont été documentées, notamment en juillet, septembre et décembre 2023. Le site de Maférinyah a enregistré le taux de positivité le plus élevé (15,57 %), contre 5,56 % à Ignace Deen. Cette étude confirme la persistance du SARS-CoV-2 et sa co-circulation avec les virus grippaux en Guinée, soulignant l'importance d'une surveillance intégrée pour anticiper les risques épidémiques et guider les politiques de santé publique. Les enfants de moins de 2 ans restent particulièrement vulnérables, justifiant des mesures préventives ciblées.

This cross-sectional study, conducted from 23 July 2023 to 23 July 2024, assessed the co-circulation of influenza viruses and SARS-CoV-2 in sentinel sites of Severe Acute Respiratory Infections (SARI) in Guinea. Of the 639 patients included, 8.29% (53 patients) were positive for the viruses, with a predominance of influenza viruses (66.03%) compared with SARS-CoV-2 (33.96%). Among the influenza viruses, subtypes H3N2 (77.77% of cases of influenza A) and B3N2 (77.77% of cases of influenza B) predominated. influenza A cases) and B Victoria (100% of influenza B cases) were the most common most frequent. The 0-2 age group was most affected (54.30% of cases), followed by the cases), followed by the 15-50 age group (18.78%). No significant differences were between the sexes or hospitalization outcomes. The results revealed distinct periods of viral circulation: SARS-CoV-2 was present almost all year round, with a peak in December 2023, while influenza viruses circulated mainly during the rainy seasons. Simultaneous co-circulations of influenza viruses and SARS-CoV-2 were documented, notably in July, September and December 2023. The Maférinyah site recorded the highest positive rate (15.57%), compared with 5.56% at Ignace Deen. This study confirms the persistence of SARS-CoV-2 and its co-circulation with influenza viruses in Guinea, underlining the importance of integrated surveillance to anticipate epidemic risks and guide public health policies. Children under the age of 2 remain particularly vulnerable, justifying targeted preventive measures.