First report of Spodoptera frugiperda (Lepidoptera: Noctuidae) on Onion (Allium cepa L.) in South Kivu, Eastern DR Congo

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

Occurrence of the sweet potato hornworm Agrius convolvuli (Lepidoptera: Sphingidae) in the Haut-Katanga province, Democratic Republic of the Congo

peer reviewedAgrius convolvuli (Lepidoptera: Sphingidae) is a pest that feeds on young sweet potato leaves causing severe plant defoliation. This study was designed to report for the first time on the occurrence of the pest in the Haut-Katanga province in DR Congo. Survey and observations were conducted during the growing season in ten cities of the Haut Katanga province to detect the presence of A. convolvuli. Fifty-two sweet potato fields were inspected during the season. Larvae and pupae were collected in each city and reared in the laboratory at the University of Lubumbashi, DR Congo. Results revealed that the pest occurs in the province with Lubumbashi and Kasumbalesa being the most highly infested with 18.80±11.36 and 18.71±8.13% of infestation, respectively. The highest number of larvae per field and per plant was recorded in Lubumbashi alone with 18.80±8.04 and 3.80±1.48, respectively. Classification of sweet potato leaf damage indicated that Kasumbalesa, Sakania and Lubumbashi had high levels of damage. Positive relationships were observed between infestation rate and number of larvae per field (R2=0.3069; t=4.705; p<0.0001) but also between infestation rate and number of larvae per plant (R2=0.4478; t=6.368; p<0.0001). The findings of the current study suggest that A. convolvuli could be a potential threat to sweet potato production in the Haut-Katanga province

Flore adventice de la tomate dans le Sud-Kivu montagneux, RD Congo

peer reviewedFlore adventice de la tomate dans le Sud-Kivu montagneux, RD Congo Description du sujet. En dépit de l’importance de la culture de tomates en Afrique centrale, peu d’études sur la flore adventice de cette culture y ont été réalisées. Objectifs. Cette étude visait à caractériser la flore adventice des cultures de tomates dans les régions montagneuses du Sud-Kivu, RD Congo. Méthode. Des inventaires floristiques ont été réalisés dans quatre zones de culture du territoire de Kabare, Sud-Kivu. Résultats. Au total, 79 espèces, réparties en 64 genres et 31 familles, ont été inventoriées. Les Asteraceae et les Poaceae constituent les familles les plus diversifiées. La flore est dominée par les thérophytes et les géophytes. La diversité spécifique était comparable entre les zones de culture, mais la composition en espèces y était variable. Sept espèces d’importance agronomique ont été identifiées : Commelina benghalensis, Galinsoga quadriradiata, Commelina diffusa, Galinsoga parviflora, Bidens pilosa, Oxalis debilis and Digitaria velutina. Conclusions. La flore adventice de la tomate dans les régions montagneuses du Sud-Kivu est diversifiée. Néanmoins, les quelques espèces problématiques sont des espèces cosmopolites

Edible insect biodiversity and anthropo-entomophagy practices in Kalehe and Idjwi territories, D.R. Congo.

peer reviewedBACKGROUND: 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

Fall Armyworm Spodoptera frugiperda (Lepidoptera: Noctuidae) in South Kivu, DR Congo: Understanding How Season and Environmental Conditions Influence Field Scale Infestations

The fall armyworm (FAW) Spodoptera frugiperda (J. E. Smith) has become a global devastating pest because of its broad dispersal capacity and the high crop damages. At present, research on FAW infestations of crops in the DR Congo remains undocumented. Here, FAW infestations in two agro-ecological zones (Kabare and Ruzizi Plain) were compared in South-Kivu Province. Surveys were carried out during the early 2018 and late 2019 crop seasons to assess the impact of FAW on maize crops. In each agro-ecological zone, 50 fields were selected for investigation. A total of hundred (100) fields were assessed in the 2018 crop season. During the 2019 crop season, the same fields were investigated. The two zones had very different bioclimatic characteristics. FAW attacks were more pronounced under conditions of relatively high temperatures with high evapotranspiration, which occurred in the Ruzizi Plain and late 2019 season. In comparison, Kabare territory and the early 2018 season were characterized by heavy rainfall. The incidence, level of leaf damage, and density of FAW larvae varied significantly with season and agro-ecological zone. The Ruzizi Plain had the highest incidence (60 ± 30%), level of leaf damage and larval density (28.5 ± 19.3). The late 2019 season had the highest incidence (70 ± 20%) as well as the larval density (27.8 ± 19.2). Total annual number of FAW generations was 5.64 and 3.36 in the Ruzizi Plain and Kabare territory, respectively. In conclusion, FAW infestation represents a major problem for agricultural production due to the climatic conditions in the study region

Managing fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae): Experience from smallholder farmers in central and western Africa

peer reviewedThe 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

Socio-economic drivers of improved sweet potato varieties adoption among smallholder farmers in South-Kivu Province, DR Congo

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