School of Agriculture, Veterinary Science and Technology

SOCIO-ECONOMIC ANALYSIS OF INDIGENOUS TECHNICAL KNOWLEDGE USE IN RICEBEAN PRODUCTION AMONG SMALL HOLDER FARMERS IN NYANZA REGION KENYA

2026-04-16T12:45:36Z

SOCIO-ECONOMIC ANALYSIS OF INDIGENOUS TECHNICAL KNOWLEDGE USE IN RICEBEAN PRODUCTION AMONG SMALL HOLDER FARMERS IN NYANZA REGION KENYA Kokwon, Costa The promotion of sustainable, climate-smart agricultural practices and crop diversification is essential for addressing food insecurity in Kenya. Despite government efforts to transform agricultural systems, progress remains uncertain, with challenges needing comprehensive solutions to ensure long-term sustainability. Ricebean, a multipurpose but underutilized legume, holds significant potential for improving crop diversity and resilience; however, its adoption is limited due to lack of knowledge and awareness among farmers and extension officers. Farmers possess indigenous technical knowledge (ITK) about ricebean, but the knowledge is neither well-documented nor integrated with scientific advances, hindering the crop's wider adoption. This study aimed to analyze the ITK used by ricebean farmers in Nyanza Region, identifying knowledge gaps and strategies to increase adoption and support sustainable ricebean production. Specific objectives of the study included: identifying farmers’ ITK on ricebean production, assessing socioeconomic factors that influence ITK adoption, evaluating farmers’ perceptions on integrating ITK in ricebean production, and comparing the prevelance rate of ITK among smallholder farmers in Migori, Siaya, and Kisii counties. Grounded in Social Cognitive Theory, the study used a cross-sectional survey design to collect data from 397 ricebean-farming households through multistage, purposive, propotionate and snowball sampling procedures in the three counties. Data collection methods included semi-structured questionnaires, FGDs guide, interviews, photographs and observations. Analysis was done using SPSS version 20. Results show that most ricebean farmers are women (70.3%) with education level of 57.2% being at primary education and an average age of 44 years. Farming is the main occupation for 88.2% of participants, with more than half earning less than Ksh 35,000 annually. Use of ITK is widespread, particularly in planting timing, land preparation and crop management, with 62% of farmers integrating ITK with scientific practices. Adoption of ITK is influenced by factors such as gender, market access and extension services (p<0.05), with men more likely to adopt ITK practices than women. Although farmers value ITK for its affordability and environmental benefits, they believe that it is not effective as its production is relatively low. County-level variations indicate that Siaya has the highest female farmer participation and lowest income levels, while Kisii leads in ricebean income generation. Similarly, ITK practices in ricebean farming vary significantly across Kisii, Migori, and Siaya counties, shaped by factors such as climate, socio-cultural preferences and resource availability. The study concludes that ricebean farming in Kisii, Migori, and Siaya counties is characterized by small-scale, female-dominated operations with significant reliance on Indigenous Technical Knowledge (ITK). However, challenges such as low incomes, limited access to education, markets and extension services hinder productivity. Policymakers should focus on improving access to credit, agricultural support systems and markets, particularly in underserved regions like Migori and Kisii. Strengthening training programs, fostering farming groups, and promoting equitable resource distribution can enhance ITK adoption, boost productivity and improve rural livelihoods.

MOLECULAR CHARACTERIZATION OF POTATO VIRUS Y AND EVALUATION OF NOVEL POTATO CLONES FOR EARLINESS AND RESISTANCE IN KENYA.

2026-04-16T12:25:00Z

MOLECULAR CHARACTERIZATION OF POTATO VIRUS Y AND EVALUATION OF NOVEL POTATO CLONES FOR EARLINESS AND RESISTANCE IN KENYA. Kithinji, Maryrose Nyakio The potato (Solanum tuberosum), is the second most important food crop in Kenya after maize and the fourth most important crop in the world after rice, wheat, and maize. Numerous pests and a broad spectrum of bacterial, viral, and fungal diseases can affect the potato crop. Potato virus Y (PVY) is one such disease that can result in up to 100% crop loss and substantial production reductions. New variations with distinct biological characteristics that affect potato production worldwide are produced as a result of PVY strain evolution. There is still little and inadequate documentation regarding its phylogeography in East Africa in comparison to the global distribution of PVY. To investigate this, a survey was conducted to assess the distribution of PVY infection in Kenya's major potato-growing areas: Kiambu, Nyandarua, Meru, Nakuru, Bomet, West Pokot, Kisii, and Bungoma. Positively identified PVY samples were subjected to sequencing to unveil the level of genetic diversity within the Kenyan potato gene pool. A randomized complete block design was used in four trial sites for potato populations from Scotland to test for earliness and PVY resistance in KALRO-Kakamega, Alupe, and Sang’alo. Seed bulking was done in Kapsokwony. Data was recorded at 40, 70, and, 90 days post-emergence to capture data for earliness and test for PVY infection in the potato cultivars. Bioinformatics tools were used for the De novo assembly and mapping, genome alignment, recombination, and phylogenetic analysis. The overall prevalence of the strains in the eight counties stood at 36.62%. PVY was more prevalent in Meru (100% affected), followed by Kiambu (61%), Bomet (40%), and Nyandarua (26.7%). Bungoma, Nakuru, Kisii, and Elgeyo Marakwet recorded 0% of PVY infection. Molecular characterization of seven potato virus Y-positive strains and a whole genome sequencing of the PVY Kenyan isolate revealed the molecular footprint of PVY in Kenya. The N-type (PVYN) and recombinant PVY strain type (PVY N:O) were prevalent in the areas of study sampled. Partial sequences of the seven potato virus Y strains identified from farmer fields deposited in the NCBI database were OR571473, OR571477, OR571474, OR571476, OR571478, OR571479, OR571475, and a complete genome of Kenyan PVY isolate, accession number PP069009. The evolutionary relationship of the Kenyan isolate PP069009 was unveiled, demonstrating a strong 92% probability of clustering with a sequence from the United States of America [JQ924287]. Population genetics analysis revealed a calculated nucleotide diversity (π) of 0.00354881, while Analysis of Molecular Variance (AMOVA) had an øST value of 0.45224. The extensive haplotype network depicted diverse PVY strains across continents. Potato population screening from Scotland was accessed at 40, 70, and 90 days post-emergence. Tests of Between-Subjects Effects combining genotypes and three field sites were significant (F = 54.43.435, DF= (61-2), P <0.05) with Sang'alo displaying the best mean phenotype of 2.6675. 12 of the 60 genotypes were selected for further processing in KEPHIS and KALRO. I, therefore, present the first molecular footprint of the Kenyan PVY whole genome (PP069009), illustratively describing its’ phylogenetic positioning, historical transmission patterns across continents, and the adaptive selection pressures, emphasizing its potential role in PVY's adaptive evolutionary process. However, I stress the need for further investigations into the specific evolutionary dynamics shaping PVY populations in distinct geographical regions, especially Africa, as the virus is continually evolving. Upon adoption, climate smart cultivars will support potato productivity among small-scale farmers. Information obtained from this study will help in policy development on managing PVY infections in Kenya.

BANANA FIBRE PAPER AS A SUSTAINABLE NEMATICIDE DELIVERY SYSTEM FOR IMPROVED NEMATODE MANAGEMENT, CROP PRODUCTIVITY AND SOIL HEALTH

2026-04-16T10:02:37Z

BANANA FIBRE PAPER AS A SUSTAINABLE NEMATICIDE DELIVERY SYSTEM FOR IMPROVED NEMATODE MANAGEMENT, CROP PRODUCTIVITY AND SOIL HEALTH Atandi, Janet Gesare Potato (Solanum tuberosum) and green pea (Pisum sativum) are important staple and legume crops in Kenya, yet their productivity is increasingly constrained by plant parasitic nematodes (PPN), including root-knot nematodes (Meloidogyne spp.) and potato cyst nematodes (Globodera spp.), as well as other biotic and abiotic stresses. Traditional nematode management approaches, including chemical nematicides, face limitations such as environmental toxicity, high cost, and restricted applicability, highlighting the need for integrated, sustainable alternatives. This study evaluated the efficacy of banana fibre paper technology, biodegradable paper treated with abamectin, fluopyram, or Trichoderma asperellum, on PPN suppression, potato cyst nematode reproduction, crop yield, and soil health in field trials in Nyandarua and Nyamira counties. Four field experiments were conducted across multiple cropping seasons, including treatments of abamectin-paper, fluopyram-paper, Trichoderma-paper, untreated paper, and controls. Nematode populations were monitored at planting and harvest while potato cyst nematode reproduction, crop yield, and soil health indicators, including free-living nematode (FLN) abundance, ecological indices, and microbial biomass were assessed at crop harvest. Data were analysed using ANOVA with significance set at p ≤ 0.05. Results revealed that banana fibre paper treatments significantly reduced PPN densities: abamectin-paper reduced nematodes by up to 48%, while fluopyram-paper achieved 58–72% reductions depending on season and cultivar. Trichoderma-paper resulted in 40–65% suppression and consistently increased yields. In peas, suppression was minimal and did not translate into yield gains. Trichoderma-paper enhanced FLN abundance and diversity, increased enrichment and structure indices by 25–40%, and boosted microbial biomass by up to 60%, whereas chemically treated papers, particularly fluopyram, elevated basal indices and lowered fungal-to-bacterial ratios, suggesting reduced soil food web complexity. This study provides novel evidence that integrating chemical and biological nematode control within a slow-release biodegradable matrix can suppress PPN while conserving or enhancing soil ecological function under smallholder conditions. The findings offer a practical, and cost effective nematode management approach for farmers in Nyandarua and Nyamira. It is recommended that future adoption focus on Trichoderma-enriched banana fibre paper and optimize pelletized formulations for improved field efficiency and ease of use.

EPIDEMIOLOGY AND CHARACTERISATION OF Groundnut Ringspot Virus (GRSV) INFECTING GROUNDNUTS AND OTHER PLANTS IN WESTERN KENYA

2024-04-11T05:57:23Z

EPIDEMIOLOGY AND CHARACTERISATION OF Groundnut Ringspot Virus (GRSV) INFECTING GROUNDNUTS AND OTHER PLANTS IN WESTERN KENYA Murere, Lubao Wanyonyi Groundnut (Arachis hypogaea L.) is an annual oilseed legume crop grown by small holder farmers in Kenya for its economic and nutritive value. However, its yield has declined upto 680 kg ha-1 than its genetic potential of 1690 kg ha-1 attributed to abiotic and biotic stressors. Viruses are among biotic stressors for yield reduction globally. These include; Groundnut ringspot virus (GRSV), Tomato spotted wilt virus (TSWV), among others. GRSV was reported in South Africa, Ghana, Brazil and USA infecting groundnuts, soybeans and others. GRSV and TSWV have similar biological symptoms but differentiated using serological tests. Typical Symptoms for GRSV appears on groundnuts and other plants in western Kenya but no report had been documented on the occurrence of the virus nor its management strategies Kenya. The general objective of this study was to determine the occurrence, distribution and characterisation of GRSV on groundnuts and other host plants in western Kenya. Survey on prevalence of GRSV, was conducted in short and long rain seasons of the years 2019 and 2020 in western Kenya. Simple random sampling (SRS) used in selecting farms visited in groundnut growing regions and disease incidence/ severity recorded and data collected analyzed using post-hoc analysisANOVA. Serological analysis was done on samples collected using polyclonal and monoclonal antisera against GRSV and TSWV respectively. Field trials on the effect of intercropping other legumes with groundnuts on GRSV incidences were laid on a randomized complete block design (RCBD) and replicated three times. Viral incidence and severity recorded and symptomatic leaf samples collected for GRSV ELISA tests. Health tested seeds to GRSV of groundnut varieties and other plant species were planted in plastic pots of a mixture of sterilized loam, sand and organic manure at a ratio of 2:1:1 respectively in greenhouse to screen for their response and host range to GRSV and inoculated with GRSV inoculum. Plants symptomatic development observed at an interval of 5 days for 8 weeks and plant samples for each variety/species collected for GRSV ELISA Tests. Total RNA of Kenyan plant isolates extracted using CTAB and purified by DCC™-5 purification kit then amplified using target primers GRSVnR (5’-GCGGTCTACAGTGTTGCACTT3’)andGRSVnF(5’TCTTGTGCATCATCCATTGT-3’) using Rt-PCR at 614-bp fragment of the nucleocapsid gene of GRSV corresponding to the part of the nucleocapsid (N) gene. The RT-PCR product taken for Sanger sequencing. Sequence readings trimmed using Bio-edit software and phylogenetic analysis done in MEGA-X. New primers from GRSV sequences of western Kenya was designed using primer3plus software, synthesized and validated using PCR tests. GRSV occurs in surveyed regions with variant incidence; Chwele having the highest incidence (45.04 %) while Kapkateny having the lowest incidence (17.75 %) with significant difference of (P < 0.05). Groundnuts planted in pure stand had lowest disease incidence (4%) while intercropped groundnuts had the highest (28%). Screened groundnuts showed Homabay variety being more susceptible with incidence of 31 %, followed by ICGV-9991 with incidence of 28 %. SM99568 variety was tolerant to the virus. Varieties ICGV-90704, ICGV-99048 and ICGV-99019 were resistant to the virus.Screened plants; Pigeon peas, Bambara nut, peas, Chenopodium album, Galinsoga parviflora among others, revealed being as host range for the virus. Kenyan GRSV isolates clustered with USA, Ghanaian and South African isolates in GenBank. One of developed primers formed clear bands in a PCR tests with positive samples of western Kenya. GRSV occurs in surveyed counties of western Kenya, which should be a big concern to all stakeholders. Introgression of resistant genes into local groundnuts to gain resistance to the virus with urgency. Farmers should avoid intercropping groundnuts with alternative hosts to reduce transmission of the virus.