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Farmer perceptions of fungal spoilage and mycotoxin contamination in East and West Africa
(Wageningen Academic, 2026-05-04) Bidzakin, J.; Graves, A.; Cervini, C.; Bernard, M.; Chala, A.; Temu, E.; Kamara, A.; Kargbo, M.; Kombiok, D.; Koudougou, B; Mbapila, S.; Mekonen, S.; Misganaw, E.; Merafina, S.; Makete, N.; Minyatta, E.; Mvena, A.; Oufensou, S.; Rizzu, M.; Kiriba, D.; Shashi, N.; Sheref, Y.; Stentella, R.; Tholley, J.; Wayua, F.; Migheli, Q.; Okoth, S.
Mycotoxins, toxic metabolites of fungi, are a major food safety concern in sub-Saharan Africa, where they compromise human and animal health, reduce food security, and limit trade. This study investigated farmer perceptions, awareness, and practices related to fungal spoilage and mycotoxin contamination across six countries in East and West Africa (Burkina Faso, Ghana, Sierra Leone, Ethiopia, Kenya, and Tanzania). Using a survey of 531 farmers, we found that 46% reported losses due to mould, with prevalence higher in East Africa (53%) than in West Africa (27%). Food losses were typically 0-20% but exceeded 60% in some cases. While most farmers (89%) reported avoiding consumption of visibly mouldy grains, 11% admitted doing so, and 74% were unaware that moulds could be harmful to health. Knowledge gaps were pronounced: 75% had never heard of mycotoxins and 88% did not know the safe grain moisture content for storage. Despite widespread use of storage technologies such as hermetic PICS bags (35%), hessian bags (30%), and polypropylene bags (28%), many farmers perceived these methods as only slightly effective. Chi-square analysis revealed significant regional differences, with East African farmers showing higher awareness of mycotoxins and safe storage practices than those in West Africa, though risky behaviours persisted in both regions. Logistic regression showed that gender, age, and access to technical knowledge were significant predictors of awareness. Specifically, women, older farmers and those with access to technical support demonstrated higher levels of awareness on fungal spoilage and mycotoxin contamination. These findings highlight the urgent need for targeted training on safe storage practices, improved dissemination of effective technologies, and integration of post-harvest management into extension services. Strengthening farmer knowledge and capacity is essential to reduce mycotoxin-related food losses, protect health, and enhance food security in African smallholder systems.
Farmer participatory evaluation of Amaranthus cruentus L. breeding lines for marketable vegetable yield and organoleptic quality under on-farm and on-station conditions
(Frontiers, 2026-05-11) Shimikilo, Ayubu; Dinssa, Fekadu; Schafleitner, Roland; Venkataramana, Pavithravani
Introduction: Amaranth (Amaranthus cruentus L.) is an important leafy vegetable crop in sub-Saharan Africa, yet limited studies integrate genotype × environment (G × E) interaction analysis with gender-disaggregated participatory selection to guide breeding decisions.Methods: This study evaluated vegetable yield performance, agronomic traits, G × E interaction, and gender-disaggregated farmer preference of 23 A. cruentus genotypes, comprising 21 advanced breeding lines and two commercial varieties, under contrasting on-station and on-farm conditions in northern Tanzania. Trials were conducted using a randomized complete block design with three replications per location.Results: Significant G × E interactions were observed for marketable vegetable yield, biomass, and morphological traits. Mean marketable yield was higher at the World Vegetable Center Eastern and Southern Africa (WorldVeg-ESA) on-station location (37.75 t/ha) than at the Himo on-farm location (31.18 t/ha). GGE biplot analysis showed that PC1 and PC2 explained 81% and 19% of the total variation, respectively. Participatory evaluation showed overlapping preferences among male and female farmers, favoring genotypes with high biomass, narrow leaves, and fast and high regrowth ability.Discussion: Three promising genotypes were identified: AVAM2402 adapted to both locations, AVAM2404 adapted to Himo, and AVAM2408 adapted to WorldVeg-ESA. These lines will be advanced for distinctiveness, uniformity, and stability (DUS) testing for possible release as commercial varieties.
Ethnobotanical Knowledge and the Distribution of Pesticidal Plants in Northern Tanzania: A Multi-Ethnic Perspective
(MDPI, 2026-04-25) Constantine, Immaculate; Giliba, Richard; Mkindi, Angela
Pesticidal plants are vital for pest management in sub-Saharan Africa, yet knowledge about them is culturally and geographically unevenly documented. This study examined ethnobotanical knowledge and the distribution of pesticidal plants among six ethnic groups (Maasai, Chagga, Iraqw, Pare, Nguu, Zigua) in northern Tanzania. Data related to ethnobotanical knowledge were collected from questionnaire surveys involving 266 participants, 24 focus group discussions, 26 key informant interviews, complemented by field verifications across the six ethnic groups. Pesticidal plant coordinates were accessed from herbarium voucher specimens from The National Herbarium of Tanzania. Chi-square tests of independence assessed associations between ethnic groups and knowledge transmission pathways. Penalized logistic regression analysis was conducted to assess the influence of demographic factors on reported knowledge of pesticidal plants. Spatial overlay was conducted to examine the distribution of pesticidal plant species occurrences across agroecological zones and rainfall gradients. The results revealed a significant association between ethnic group and the source of pesticidal plant knowledge. Across all ethnic groups, knowledge was predominantly acquired through family/community traditional sources, with the highest frequencies recorded among the Maasai, Iraqw, and Zigua. Knowledge is mainly transmitted orally, particularly among the Maasai, Iraqw, and Zigua. A total of one hundred and six distinct species were recorded across the six ethnic groups surveyed, with Tephrosia vogelii and Solanum incanum being the most frequently cited. Leaves were the most frequently used plant part across all ethnic groups, with notably high usage among the Chagga, Iraqw, and Maasai. Perceptions of the declining population of pesticidal plants were the highest among the Maasai. Spatial mapping revealed pesticidal plant hotspots in the Northern Rift and Volcanic Highlands agroecological zones, and they fall within zones receiving moderate to relatively high rainfall. The findings highlight that ethnobotanical knowledge of pesticidal plants in northern Tanzania is strongly shaped by ethnic affiliation, oral knowledge transmission, and localized ecological availability, with clear spatial hotspots aligned to specific agroecological zones and high-rainfall areas.
Early Symptom Characterisation and Mitigation of Maize Lethal Necrosis Disease
(John Wiley and Sons, 2026-05-21) Kpai, Patrick Yawo; Adaramola, Oluwafemi; Addo, Philip Wiredu; MacPherson, Sarah; Mashamba, Philipo; Lefsrud, Mark
Maize (Zea mays) is a staple crop central to food security and livelihoods across sub-Saharan Africa. In recent years, maize production in the region has been severely affected by maize lethal necrosis disease (MLND). First reported in Kenya in 2011, MLND has spread rapidly across eastern and central Africa, leading to significant yield reductions and serious socioeconomic impacts on smallholder farmers. The study examined early symptom development of MLND and evaluated the effects of foliar boron and exogenous RNase A on the growth of maize plants inoculated with MLND-infected sap. Two completely randomised trials were conducted 1 week after inoculation to assess maize growth responses to varying foliar boron concentrations and exogenous RNase A over 14 days. Stem inoculation induced a progressive sequence of foliar symptoms 2 days postinoculation, from discrete lesions and faint chlorotic streaks to extensive mosaic yellowing and tissue collapse. Advanced infection caused apical meristem death in 28.9% of the inoculated plants, triggering compensatory lateral shoot growth. Foliar application of exogenous RNase A resulted in statistically similar (p > 0.05) growth traits when compared to the inoculated plants with no treatments. However, foliar application of boron at a concentration of 15 mg L−1 resulted in significantly higher (p < 0.05) aboveground biomass yield when compared to the inoculated plants with no treatments. Molecular and serological analyses show that boron application at 15 mg L−1 effectively suppressed viral accumulation to below detectable levels. These findings provide a basis for developing low-cost strategies to manage the disease.
Derivation of seed viability constants (CW, KE) and predicting seed longevity for jute mallow (Corchorus capsularis and C. olitorius)
(Ingenta Connect, 2026-05-23) Shango, Abdul; Mosha, Emmanuel; N’Danikou, Sognigbé; Ramadhani, Shebati; Kamala, Moses; Sumaye, Saphina; Venkataramana, Pavithravani; Mtui, Hosea; Philipo, Mashamba; Kusolwa, Paul; van Zonneveld, Maarten
Genebanks support long-term germplasm conservation and ensure availability of viable seeds to users. The improved seed viability equation enables prediction of longevity by combining species-specific moisture content constants (CW, KE) with universal temperature constants (CH = 0.0329; CQ = 0.000478). While the number of genebank collections of jute mallow (Corchorus capsularis and C. olitorius) has significantly increased in recent years, such constants are lacking to support management. To derive CW and KE and predict longevity, seeds of both species were equilibrated to five moisture content levels (7.5-12.2%) and subjected to experimental storage at 60°C for 25 or 35 days for C. olitorius and C. capsularis, respectively. The viability constants were then estimated as CW = 6.80 and KE = 10.78 for C. capsularis and CW = 6.21 and KE = 10.06 for C. olitorius. The validation of the derived constants indicated good agreement between predicted and observed viability at high viability levels in both species, with increasing divergence as seeds deteriorated. The predicted seed longevity under genebank conditions indicated that C. capsularis seeds live longer than C. olitorius. The derived constants provide a practical tool for genebanks to optimise germplasm regeneration cycles and minimise the risk of genetic erosion.