Summary: Bananas ( Musa spp.) are considered the most important fruit crop in Kenya, grown mostly by smallholder farmers. However, in the past two decades production has declined and has largely been attributed to plant pathogens, including plant-parasitic nematodes. To assess the understanding and awareness that banana farmers have of nematodes, a survey was conducted. The incidence, abundance and distribution of nematodes in relation to altitude were determined for different banana types on 180 farms and the pathogenicity of Pratylenchus goodeyi , originating from three different altitudinal locations, was compared on two banana cultivars. Just 2.3% of farmers were aware of nematode damage and symptoms, none of whom applied any management measures. The highest abundance of nematodes was recorded at an altitude range of 1601-2000 m a.s.l., with Pratylenchus , Meloidogyne and Helicotylenchus being the predominant genera. Across all altitudinal locations, cooking banana had higher densities of nematodes than dessert bananas. In pots, P. goodeyi populations from Embu (1300 m a.s.l.) appeared more aggressive and with higher levels of multiplication than the population from Oyugis (1100 m a.s.l.). Cooking banana (‘Ng’ombe’) was more susceptible than dessert banana (‘Sukari Ndizi’). Nematode damage is more prominent in areas at higher altitude and on cooking banana cultivars. The findings provide key information in guiding informed and suitable management decision thresholds in relation to potential climate change.

Potato (Solanum tuberosum) is a key staple crop in Kenya, where plant-parasitic nematodes are among the most damaging yield constraints for smallholder farmers. This study evaluated fluopyram-treated banana fibre paper, a biodegradable carrier for targeted delivery of ultra-low nematicide doses, under on-farm conditions in Nyandarua County over three consecutive cropping seasons across properly and poorly managed fields. Seventeen nematode genera were identified, with Helicotylenchus and Globodera (potato cyst nematode, PCN) recording the highest population densities. Fluopyram-treated banana paper significantly suppressed Globodera juvenile densities and reduced total nematode reproductive factors by ≥26% and PCN cyst multiplication factors, effects most pronounced under poor management. No significant nematode suppression was observed under good management. Potato yield and quality responded positively to fluopyram treatment: total yield approximately doubled in well-managed plots and increased by ~50% in poorly managed plots relative to untreated controls. Fluopyram-treated plots also produced a higher proportion of large-grade tubers under proper management, improving marketable yield. These findings demonstrate that banana fibre technology can effectively manage nematode pests under variable real-world smallholder conditions, with yield benefits amplified by good agronomic practices. The technology offers a practical, climate-smart and sustainable nematode management tool, with potential for wide adoption across sub-Saharan Africa.

Potato (Solanum tuberosum) is a key staple crop in Kenya, where plant-parasitic nematodes are among the most damaging yield constraints for smallholder farmers. This study evaluated fluopyram-treated banana fibre paper, a biodegradable carrier for targeted delivery of ultra-low nematicide doses, under on-farm conditions in Nyandarua County over three consecutive cropping seasons across properly and poorly managed fields. Seventeen nematode genera were identified, with Helicotylenchus and Globodera (potato cyst nematode, PCN) recording the highest population densities. Fluopyram-treated banana paper significantly suppressed Globodera juvenile densities and reduced total nematode reproductive factors by ≥26% and PCN cyst multiplication factors, the effects most pronounced under poor management. No significant nematode suppression was observed under good management. Total yield in fluopyram treatment approximately doubled in well-managed plots and increased by ~50% in poorly managed plots relative to untreated controls. Fluopyram-treated plots also produced a higher proportion of large-grade tubers under proper management, improving marketable yield. These findings demonstrate that banana fibre technology can effectively manage nematode pests under variable real-world smallholder conditions, with yield benefits amplified by good agronomic practices. The technology offers a practical, climate-smart, and sustainable nematode management tool, with potential for wide adoption across sub-Saharan Africa.