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Abstract Background The fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), poses a threat to the food security of populations in sub-Saharan Africa because of its damage to maize crops. As alternative to the use of hazardous pesticides, microbial control is one of the most promising sustainable approaches adopted to limit the damages caused by S. frugiperda. The sampling targeted mainly larvae of S. frugiperda; however, during the survey, cadavers of earwig found on the same sampling sites were also collected and involved in the study. Cadavers of targeted insects, with and without sign of fungal infection, were sampled from 3 localities in eastern DR Congo. Culture of fungal isolates was performed in selective Sabouraud dextrose agar media. Results Morphological study of fungal features such as conidia (shape and size) and conidiophores showed that the isolates were from the genus Beauveria. Conidial measurements were highly variable and ranged from 2.4 to 3.6 µm in length and from 1.75 to 3.0 µm in width. Molecular characterization and phylogenetic analysis of the 2 Beauveria isolates based on DNA sequencing of ITS-5.8S region confirmed that both isolates belong to Beauveria bassiana. The 2 isolates of B. bassiana P5E (OP419735.1) and KA14 (OP419734.1) were isolated from cadavers of FAW and earwig, respectively. The alignment with different sequences of B. bassiana from different continent showed that P5E belonged to the same clade of previous isolates reported from Iran and Mexico, while KA14 was with the same clade as isolates from Kenya and China. Conclusion To our knowledge, this is the first study reporting the occurrence of B. bassiana infecting FAW and earwig in eastern DR Congo and in Africa.

Abstract The fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), is currently an important pest of maize crops worldwide not only because of its dispersal ability but also because of its polyphagous feeding behaviour. Lack of sufficient information on the management of the fall armyworm attacks remains a crucial problem for maize smallholder farmers in Africa. In this study, 420 farmers were surveyed in central and west Africa using individual interviews to assess farmers' knowledges and perceptions of the fall armyworm damages and the management practices used. Most farmers (99.4%) were shown to recognize the fall armyworm and 92.5% claimed to already have damages in their fields. The fall armyworm seems not to be a new pest as most farmers identified it in different countries from 2015 to 2019. Apart from maize as the preferred crop of S. frugiperda, several alternative host plants including Napier grass, sorghum, onion, and cabbage were identified by the farmers. Although cultural and mechanical control methods are used by several farmers, the synthetic pesticide market is still preferred by almost half of the farmers (44.28%) who still use them. To control fall armyworm, 96.4% in Burkina Faso, 85.3% in Gabon, 65.2% in Benin and 25% in DR Congo reported using insecticides, against 5.9% in Senegal. Semiochemical‐based method and biological control by promoting natural enemies of the fall armyworm are new concepts for farmers in DR Congo, Gabon and Benin. To avoid additional problems regarding health and resilience of agricultural systems, alternative methods such as push–pull approach, the development of biopesticides and resistant cultivars should form the basis of training given to farmers and should be popularized for sustainable control of the fall armyworm in central and west Africa.

Abstract Background Located in the Eastern Democratic Republic of Congo (South-Kivu), Kalehe and Idjwi are two relatively unexplored territories with little to no research on edible insects even though anthropo-entomophagy practice is widespread. This study therefore aimed at exploring the biodiversity, perception, consumption, availability, host plants, harvesting techniques, and processing techniques of edible insects. Methods Data were collected through a field survey using three techniques, namely structured interviews, direct observations, and insect collection and taxonomy. A total of 260 respondents, 130 in each territory, were interviewed. The field survey focused on inventorying commonly edible insects as well as recording consumer preferences, preference factors, seasonal availability, host plants, harvesting techniques, and processing and preservation methods. Samples for taxonomic characterization were preserved in 70% alcohol. Results Nine edible insects, namely Ruspolia differens Serville 1838, Gryllotalpa Africana Palisot de Beauvois 1805, Locusta migratoria Linnaeus 1758, Macrotermes subhyalinus Rambur 1842, Gnathocera trivittata Swederus 1787, Rhynchophorus phoenicis Fabricius 1801, Vespula spp. Linnaeus 1758, Apis mellifera Linnaeus 1758, and Imbrasia oyemensis Rougeot 1955, were recorded as being consumed either as larvae, pupae, and adults. Ruspolia differens and M. subhyalinus were reported as the most preferred by consumers in the studied territories. A scatter plot of matrices and Pearson's correlations showed a negative correlation between preference based on taste, size, and shape, as well as perceived nutritional value. Their seasonal availability differs from one species to another and correlated with host plants availability. Harvesting techniques and processing and preservation methods depend on species, local knowledge, and practices. Conclusion The huge edible insect diversity observed in Kalehe and Idjwi is evidence of anthropo-entomophagy practices in the area. In addition to being an important delicacy and traditional foods, edible insects can contribute to food, environmental, and financial security through local business opportunities. Households can rely on edible insects to meet their nutritional needs instead of conventional livestock. Indigenous practices and technologies used for harvesting, processing, and preserving edible insects must be improved to meet international standards to increase the market and capitalize on the economic potential of edible insects.

Description of the subject. Despite the importance of tomato in Central Africa, little is known about the weed flora occurring in tomato crops in this part of the world. Objectives. We aimed to provide a comprehensive description of the weed flora found in tomato crops in the mountainous region of South Kivu, DR Congo. Method. Floristic inventories were made in four cultivation zones of the Kabare territory, South Kivu. Results. In total, 79 species (belonging to 64 genera and 31 families) were recorded. The most species-rich families were Asteraceae and Poaceae. Therophytes and geophytes were the dominant life forms. Weed diversity was not significantly different between sites but species composition varied considerably, likely in relation to soil type. Based on the frequency and the abundance, the most problematic weeds were Commelina benghalensis, Galinsoga quadriradiata, Commelina diffusa, Galinsoga parviflora, Bidens pilosa, Oxalis debilis and Digitaria velutina. Conclusions. The weed flora in tomato fields of the mountainous regions of DR Congo is diversified, but only a few cosmopolitan species are problematic.

Abstract Background The fall Armyworm (FAW) Spodoptera frugiperda (JE Smith), is currently a devastating pest throughout the world due to its dispersal capacity and voracious feeding behaviour on several crops. A MaxEnt species distributions model (SDM) was developed based on collected FAW occurrence and environmental data’s. Bioclimatic zones were identified and the potential distribution of FAW in South Kivu, eastern DR Congo, was predicted. Results Mean annual temperature (bio1), annual rainfall (bio12), temperature seasonality (bio4) and longest dry season duration (llds) mainly affected the FAW potential distribution. The average area under the curve value of the model was 0.827 demonstrating the model efficient accuracy. According to Jackknife test of variable importance, the annual rainfall was found to correspond to the highest gain when used in isolation. FAWs’ suitable areas where this pest is likely to be present in South Kivu province are divided into two corridors. The Eastern corridor covering the Eastern areas of Kalehe, Kabare, Walungu, Uvira and Fizi territories and the Western corridor covering the Western areas of Kalehe, Kabare, Walungu and Mwenga. Conclusions This research provides important information on the distribution of FAW and bioclimatic zones in South Kivu. Given the rapid spread of the insect and the climatic variability observed in the region that favor its development and dispersal, it would be planned in the future to develop a monitoring system and effective management strategies to limit it spread and crop damage.

Abstract Understanding the typology of smallholder maize farmers is crucial to elucidate the diversity in local farming systems, and therefore, devise effective interventions and policies that maximize the impact of agricultural innovations in South-Kivu province, eastern Democratic Republic of Congo (DRC). This study aimed at characterizing maize farmers in South-Kivu province and clustering them based on various socioeconomic and agronomic factors to identify specific production constraints and devise more effective interventions. A household survey among 300 South-Kivu maize farmers allowed to identify four distinct clusters based on farm size, land use, income, and agricultural technology adoption. The clusters ranged from resource-poor smallholder (Types 1 and 2) to medium-resource semi-innovative producers (Type 3) and highly equipped innovative farmers (Type 4). Key discriminative factors included total farm size, maize farm size, farming experience, access to agricultural credit, income, and innovation adoption rate. This study revealed specific constraints for each cluster, including low soil fertility, poor weed management, low market access, and labor scarcity. This study’s findings demonstrate the value of farm typology in guiding targeted interventions to address specific constraints and improve maize productivity, and suggest specific strategic directions for research and development projects in rural areas of the South-Kivu province.

Promotion of improved crop varieties is an effective means of increasing farm productivity and alleviating poverty in rural areas. A successful dissemination of such varieties requires a deep understanding of target farmers’ attitudes, preferences and socio-economic status. This study aimed at assessing factors linked to smallholder farmers’ adoption decision for improved sweet potato varieties (ISPVs) in South-Kivu. A household survey was conducted on 360 smallholder farmers from four South-Kivu territories, in eastern Democratic Republic of Congo (DRC), including Idjwi, Kabare, Kalehe and Walungu, and data were analyzed using a logit regression model. The adoption decision was negatively affected by farmers’ age and the field-to-house distance. In contrast, the ISPVs adoption was favored by farmers’ education level, reduced farm size, off-farm incomes, high monthly income and use of hired farm labor. Besides, farmers’ cooperative membership, access to credit and planting materials, and contacts with extension services were instrumental in adopting improved sweet potato varieties in South-Kivu. This study highlighted the need to strengthen extension services, seed delivery systems, and amending the credit systems for increased impact on improved varieties adoption among South-Kivu sweet potato farmers.

ABSTRACT The fall armyworm, Spodoptera frugiperda (J. E. Smith, 1797), has become one of the most devastating pests in the world with diverse host range. To develop effective integrated management strategies against S. frugiperda, it is crucial to know its alternative host plants. In this study, we provide the first information on the occurrence of S. frugiperda in onion crops in Africa. Monitoring was carried out during the 2019 and 2020 growing seasons in onion monoculture and in intercropping with groundnut to detect the presence and assess the incidence of S. frugiperda. The highest average incidence (2.88%) and larval density (0.79 per 9 m2) were observed in onion monoculture. The classification of the onion leaf damage rating scale indicated low S. frugiperda infestation. This suggests that future studies will need to assess this aspect which we consider to be a survival strategy to maintain its population throughout the year, which contributes to sustain the insect in the study area during times when its preferred hosts are not present. Furthermore, genetic studies are needed to provide a better explanation of the ecology of this pest and to find out which of the two existing strain infests onions or whether it is an unknown hybrid population of S. frugiperda.

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Purpose: As coronavirus disease 2019 (COVID-19) continues to spread rapidly causing approximately 186 million confirmed cases around the world, the urgency to reach herd immunity through vaccination is increasing. However, vaccine safety is a top priority to limit the occurrence of adverse events. Henceforth, this study aims to recognize and perceive COVID-19 vaccine safety in Indonesia during the pandemic., Materials and Methods: This is a cross-sectional study and was conducted in Indonesia during the COVID-19 pandemic using an online survey of demographic information and a qualitative questionnaire. Responses were recorded and the association between demographic characteristics from survey questions was tested using chi-square with a risk estimate and 95% confidence interval., Results: A total of 311 participants from 33 out of 34 provinces in Indonesia participated in this study. Recorded responses showed multiple side effects of the COVID-19 vaccine both short- and long-term experienced by the participants. Significant associations were found between demographic factors and COVID-19 vaccine side effects such as female gender with short-term puncture site (odds ratio [OR], 0.463; 95% confidence interval [CI], 0.263-0.816) and short-term other reactions (OR, 0.463; 95% CI, 0.263-0.816), domicile outside Java island with long-term puncture site (OR, 4.219; 95% CI, 1.401-12.701) and immune reactions (OR, 3.375; 95% CI, 1.356-8.398), also between married marital status and long-term vagal reaction (OR, 4.655; 95% CI, 1.321-16.409)., Conclusion: Gender, domicile and marital status factors were associated with COVID-19 vaccine side effects in Indonesian people., Competing Interests: No potential conflict of interest relevant to this article was reported., (© Korean Vaccine Society.)

Background: Sinovac was the first vaccine used in Indonesia against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, data regarding the effects of certain variables such as clinical demographics on antibody levels in individuals vaccinated with Sinovac are scarce. This study aimed to investigate the impact of gender and previous SARS-CoV-2 infection status on neutralizing antibody titers 1, 2, and 3 months after administration of the Sinovac vaccine., Method: A cross-sectional study was conducted from February to May 2021. Data on neutralizing antibody levels, previous SARS-CoV-2 infection status, and gender were retrieved from the monthly quantitative serology evaluation database of Siloam Hospitals Lippo Village, Tangerang, Indonesia. The role of each variable was analyzed using the t-test or Mann-Whitney U test, depending on data distribution., Result: Data from 350 participants were collected for the study. Participants with a history of a positive SARS-CoV-2 RT-PCR test had significantly higher neutralizing antibody titers in the first (144 U/mL, p = 0.036) and second months (144 U/mL, p = 0.005) after vaccination compared with those without a history of positive RT-PCR test. Female participants also had significantly higher neutralizing antibody titers in the first, second, and third months (43 U/mL, 42 U/mL, and 39 U/mL, respectively; p = 0.001, p = 0.002, and p = 0.003, respectively) after vaccination compared to males., Conclusion: COVID-19 survivor status and the female gender were associated with higher neutralizing antibody titers after Sinovac vaccine administration., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Using geo-referenced case data, we present spatial and spatio-temporal cluster analyses of the early spread of the 2013-2015 chikungunya virus (CHIKV) in Dominica, an island in the Caribbean. Spatial coordinates of the locations of the first 417 reported cases observed between December 15th, 2013 and March 11th, 2014, were captured using the Global Positioning System (GPS). We observed a preponderance of female cases, which has been reported for CHIKV outbreaks in other regions. We also noted statistically significant spatial and spatio-temporal clusters in highly populated areas and observed major clusters prior to implementation of intensive vector control programs suggesting early vector control measures, and education had an impact on the spread of the CHIKV epidemic in Dominica. A dynamical identification of clusters can lead to local assessment of risk and provide opportunities for targeted control efforts for nations experiencing CHIKV outbreaks.

Highly anomalous crystallization behavior has been achieved in phase-inverting emulsion systems by using nonionic surfactants that induce nucleation. In particular, nucleation can be inhibited at the phase inversion, allowing systems held at, or near, this temperature to undergo crystallization either on heating or cooling. This new phenomenon is demonstrated for 27.4 wt % aqueous glycine solutions emulsified in decane using Span 20 Tween 20 blends. The inhibitory effect on interfacial nucleation at/near the phase inversion is readily shown by the maximum in the induction time for crystallization found in systems at/near the phase-inversion temperature. These findings are unprecedented. An extremely rapid rise in nucleation rate is expected on cooling glycine solutions, owing to the associated increase in supersaturation, the driving force for crystallization. The origin of this highly anomalous behavior is thought to be the low droplet interfacial tension, gammaow, that occurs at the phase-inversion temperature, which results primarily in a substantially increased contact angle between the glycine critical nucleus and the droplet interface. This may present a paradigm shift in crystallization strategies through the use of tunable contact-angle nucleators.