The incidence of sweet potato virus disease and virus resistance of sweet potato grown in Uganda

Sweet potato virus disease (SPVD) was common (25–30% average incidences), and farmers recognised it as an important disease, in sweet potato crops in southern Mpigi, Masaka and Rakai Districts in Uganda, but SPVD was rare in Soroti and Tororo Districts. Whiteflies, which are the vector of sweet potato chlorotic stunt crinivirus (SPCSV) a component cause of SPVD, were correspondingly common on sweet potato crops in Mpigi and rare on crops in Tororo. However, aphids, which are the vectors of sweet potato feathery mottle potyvirus (SPFMV), the other component cause of SPVD, were not found colonising sweet potato crops, and itinerant alate aphids may be the means of transmission. Different sweet potato cultivars were predominant in the different districts surveyed and four local cultivars obtained from Kanoni in S. Mpigi, where whiteflies and SPVD were common, were more resistant to SPVD than four cultivars from Busia in Tororo District, where whiteflies and SPVD were rare. However, nationally released cultivars were even more resistant than the local cultivars from Kanoni. Yield results and interviews with farmers indicated that farmers in S. Mpigi were making compromises in their choice of cultivars to grow, some key factors being SPVD susceptibility, and the yield, taste, and marketability, duration of harvest and in-ground storability of the storage roots. These compromises need to be included in an assessment of yield losses attributable to SPVD.     

Aspects of resistance to sweet potato virus disease in sweet potato

In field trials during the first and the second rainy season of 1996 in Uganda, whiteflies were similarly abundant and aphids were absent on three clones of sweet potato (NIS-93–63, cv. Tanzania and cv. New Kawogo) although the three clones differed considerably in their resistance to sweet potato virus disease (SPVD), a complex disease resulting from infection by both the aphid-borne sweet potato feathery mottle virus (SPFMV) and the whitefly-borne sweet potato chlorotic stunt virus (SPCSV). This suggests that vector resistance does not determine the relative SPVD resistance of these genotypes. SPFMV alone had only a low virus titre in sweet potato cvs Tanzania and New Kawogo, became increasingly difficult to detect in plants of these cultivars and was seldom acquired by aphids. However, this resistance to SPFMV was not apparent in plants which were also infected with SPCSV. Plants then had a high SPFMV titre, appeared unable to eliminate SPFMV and provided good sources for aphids to acquire it.     

Targeting of SPCSV-RNase3 via CRISPR-Cas13 confers resistance against sweet potato virus disease

Sweet potato (Ipomoea batatas) is one of the most important crops in the world, and its production rate is mainly decreased by the sweet potato virus disease (SPVD) caused by the co-infection of sweet potato chlorotic stunt virus (SPCSV) and sweet potato feathery mottle virus. However, methods for improving SPVD resistance have not been established. Thus, this study aimed to enhance SPVD resistance by targeting one of its important pathogenesis-related factors (i.e., SPCSV-RNase3) by using the CRISPR-Cas13 technique. First, the RNA targeting activity of four CRISPR-Cas13 variants were compared using a transient expression system in Nicotiana benthamiana. LwaCas13a and RfxCas13d had more efficient RNA and RNA virus targeting activity than PspCas13b and LshCas13a. Driven by the pCmYLCV promoter for the expression of gRNAs, RfxCas13d exhibited higher RNA targeting activity than that driven by the pAtU6 promoter. Furthermore, the targeting of SPCSV-RNase3 using the LwaCas13a system inhibited its RNA silencing suppressor activity and recovered the RNA silencing activity in N. benthamiana leaf cells. Compared with the wild type, transgenic N. benthamiana plants carrying an RNase3-targeted LwaCas13a system exhibited enhanced resistance against turnip mosaic virus TuMV-GFP and cucumber mosaic virus CMV-RNase3 co-infection. Moreover, transgenic sweet potato plants carrying an RNase3-targeted RfxCas13d system exhibited substantially improved SPVD resistance. This method may contribute to the development of SPVD immune germplasm and the enhancement of sweet potato production in SPVD-prevalent regions.     

Resistance to sweet potato virus disease (SPVD) in wild East African Ipomoea

Sweet potato virus disease (SPVD), the most harmful disease of sweet potatoes in East Africa, is caused by mixed infection with sweet potato feathery mottle potyvirus (SPFMV) and sweet potato chlorotic stunt crinivirus (SPCSV). Wild Ipomoea spp. native to East Africa (J cairica, I. hildebrandtii, I. involucra and J wightii) were graft-inoculated with SPVD-affected sweet potato scions. Inoculated plants were monitored for symptom development and tested for SPFMV and SPCSV by grafting to the indicator plant J setosa, and by enzyme-linked immunosorbent assay (ELISA). Virus-free scions of sweet potato cv. Jersey were grafted onto these wild Ipomoea spp. in the field, and scions collected 3 wk later were rooted in the greenhouse and tested for viruses using serological tests and bioassays. In all virus tests, J cairica and J involucra were not infected with either SPFMV or SPCSV. J wightii was infected with SPFMV, but not SPCSV, in the field and following experimental inoculation; J hildebrandtii was infected with SPCSV, but not SPFMV, following experimental inoculation. These data provide the first evidence of East African wild Ipomoea germplasm resistant to the viruses causing SPVD.     

Stability of Sweet Potato Cultivars to Alternaria Leaf and Stem Blight Disease

Alternaria leaf petiole and stem blight is an economically important disease of sweet potato ( Ipomoea batatus L.) in tropical and sub-tropical environments. Published research on cultivar resistance to the sweet potato disease is limited. To evaluate cultivar reaction and stability to the disease, multi-location and replicated experiments were established in 12 environments in Uganda. Disease severity (area under disease progress curves – AUDPC), and cultivar root yield were also assessed. Significant differences (P < 0.001) in AUDPC were detected among cultivars. Mean AUDPC ranged from 46.3 (Araka Red) to 78.4 (New Kawogo) across locations and seasons and the genotypes Araka Red and Tanzania had the lowest disease values. The location and season effects accounted for 67.1% and 7.5% of the total variance of AUDPC recorded among cultivars. The ranking of cultivars based on predicted AUDPC from Additive Main Effect and Multiplicative Interactive model (AMMI) showed that the NASPOT 1, the susceptible check, and New Kawogo were most susceptible to the disease in 11 of the 12 environments. Low and stable disease was consistently recorded and predicted on NASPOT 3 and the landrace cultivars Tanzania, Dimbuca, and Araka Red across environments. These results suggest that landrace cultivars had relative stability to the disease and wide adaptation across environments. These results suggest that AMMI statistical model and other multivariate techniques can be utilized for prediction of Alternaria disease stability in these locations.     

Current characteristics of cassava mosaic disease in postepidemic areas increase the range of possible management options

As a case study to document the current characteristics of cassava mosaic virus disease (CMD) in postepidemic areas, surveys were carried out, in 2003 and 2004, in Siaya District of western Kenya. This was an area affected by a severe CMD pandemic in the late 1990s. Data recorded on cassava varieties were CMD incidence, severity index and number of adult whiteflies. Farmers (174) were interviewed on their understanding of the disease and their knowledge and practice of management interventions. Cassava cultivation was being re‐established, but local landraces predominated. Resistant varieties were present 13% in 2003, and 4% in 2004, of the surveyed fields. Adhiambolera was the most common variety, occurring in 35% and 40% of fields in 2003 and 2004, respectively, and had an average CMD incidence of 82% in 2003 and 73% in 2004. By contrast, the CMD‐resistant variety Migyera had a low mean incidence (28% in 2003). The overall incidence for both years was 71%, consisting of 61% as a result of infection through planting diseased cuttings and 10% as a result of whitefly infection. In 2003, the total incidence was 72% and the average severity 2.7 (severity index), while in 2004 the incidence was 78% and the severity 2.6. There were significant severity variations in each division of the Siaya District during the 2 years except for Karemo and Ukwala. The abundance of whiteflies on the top five leaves of plants was low in 2003 but high in 2004, with means of 1 and 16, respectively, over the same seven divisions in both years, although this variation was thought to be because of seasonal factors. East African cassava mosaic virus‐Uganda was the predominant geminivirus present in every division. Phytosanitation by farmers was minimal, as evidenced by 29% of farmers using a selection of CMD‐free stems for planting and 15% using hand‐roguing for CMD management. Occurrence of more than 25% CMD‐free plants in 2004, moderate CMD severity and limited spread provide a conducive environment for the use of phytosanitation as a CMD control measure that can be immediately used by farmers growing their own cassava varieties.     

The Effect of the Sequence of Infection of the Causal Agents of Sweet Potato Virus Disease on Symptom Severity and Individual Virus Titres in Sweet Potato cv. Beauregard

Sweet potato virus disease (SPVD) is caused by dual infection of plants with Sweet Potato Feathery Mottle Virus (SPFMV) and Sweet Potato Chlorotic Stunt Virus (SPCSV). Because SPFMV and SPCSV are transmitted by aphids and whiteflies, respectively, infection in nature occurs independently rather than simultaneously. To investigate the effect of consecutive infection on symptom development and individual virus titres, plants infected with a single virus were later inoculated with the second virus. Symptoms were significantly more severe in plants infected with SPCSV followed by SPFMV compared to plants infected with SPFMV followed by SPCSV. Virus titres were not significantly different for SPCSV, but SPFMV titres, in plants infected with SPCSV followed by SPFMV, were significantly higher than all other treatments. The results indicate that the sequence of infection of sweetpotato plants with the causal agents of SPVD influence the severity of symptoms and SPFMV titres in SPVD affected plants.     

Maize seed selection by East African smallholder farmers and resistance to Maize streak virus*

Interviews identified that most small‐scale maize farmers in central Uganda and in the Southern Highlands of Tanzania plant home‐saved seed of landraces or seed derived from various open‐pollinated and hybrid varieties. Some farmers also bought a portion of their seed, either certified seed, locally traded seed or even maize sold for consumption. Selection for home‐saved seed was generally among harvested cobs. Big cobs with many, regularly arranged, large, white, flint kernels were preferred. A maize cob may bear several hundred seeds, so a farmer needs to save <1% of cobs for seed. A form of resistance in which plants show only moderate symptoms and suffer only a small reduction in yield when infected has been incorporated in some released varieties. Because not all plants in most crops are infected and because plants uninfected with Maize streak virus (MSV) tend to produce bigger cobs than infected resistant plants, the few cobs selected by a farmer for seed may all be from the uninfected ‘escapes’, with no preferential selection of resistant types. On‐station simulation of the farmers’ selection process in a crop of the MSV‐resistant maize variety, Longe 1, confirmed this. An alternative very strong form of MSV resistance was identified.     

Factors Influencing Diversity of Farmers’ Varieties of Sweet Potato in Uganda: Implications for Conservation

Factors Influencing Diversity of Farmers’ Varieties of Sweet Potato in Uganda: Implications for Conservation. There is increasing concern that agricultural intensification is causing loss of crop biodiversity due to displacement of traditional farmers’ varieties by a small number of improved cultivars. Using ethnobotanical surveys, we assessed the implication of adoption of new sweet potato (Ipomoea batatas) cultivars on the maintenance of farmers’ varieties in Uganda. Other factors influencing varietal diversity were also assessed. A total of 102 farmer households distributed in the top three sweet potato production agro-ecological zones were interviewed. With the exception of released cultivars, very few varieties appeared in more than one region. The majority of the respondents indicated that they continue to plant some of the existing varieties when they adopt new cultivars. Loss of planting materials due to drought was a major constraint to maintaining varietal diversity for this vegetatively propagated crop. Limited land and lack of access to best management practices were also key constraints to maintenance of farmers’ varieties. The primary criteria for adopting new cultivars were higher yield, taste, and duration to maturity. Yield stability, tolerance to native biotic and abiotic stresses, and good taste were important for maintenance of currently grown varieties. Overall, criteria for variety selection varied with household characteristics including farmer age and gender, uses of the crop, micro-climatic conditions in the farmers’ fields, and level of access to agricultural extension. The observed heterogeneity in selection criteria, influence of social ties, and the role of environment in varietal maintenance have important implications for establishing breeding priorities and preservation of crop diversity.     

Assessment of Genetic Diversity of Sweet Potato in Puerto Rico

Sweet potato (Ipomoea batatas L.) is the seventh most important food crop due to its distinct advantages, such as adaptability to different environmental conditions and high nutritional value. Assessing the genetic diversity of this important crop is necessary due to the constant increase of demand for food and the need for conservation of agricultural and genetic resources. In Puerto Rico (PR), the genetic diversity of sweet potato has been poorly understood, although it has been part of the diet since Pre-Columbus time. Thus, 137 landraces from different localities around PR were collected and subjected to a genetic diversity analysis using 23 SSR-markers. In addition, 8 accessions from a collection grown in Gurabo, PR at the Agricultural Experimental Station (GAES), 10 US commercial cultivars and 12 Puerto Rican accessions from the USDA repository collection were included in this assessment. The results of the analysis of the 23 loci showed 255 alleles in the 167 samples. Observed heterozygosity was high across populations (0.71) while measurements of total heterozygosity revealed a large genetic diversity throughout the population and within populations. UPGMA clustering method revealed two main clusters. Cluster 1 contained 12 PR accessions from the USDA repository collection, while cluster 2 consisted of PR landraces, US commercial cultivars and the PR accessions from GAES. Population structure analysis grouped PR landraces in five groups including four US commercial cultivars. Our study shows the presence of a high level of genetic diversity of sweet potato across PR which can be related to the genetic makeup of sweet potato, human intervention and out-crossing nature of the plant. The history of domestication and dispersal of sweet potato in the Caribbean and the high levels of genetic diversity found through this study makes sweet potato an invaluable resource that needs to be protected and further studied.     

Reproductive incompatibility and cytochrome oxidase I gene sequence variability amongst host-adapted and geographically separate Bemisia tabaci populations (Hemiptera: Aleyrodidae)

Abstract. Reciprocal‐crossing experiments were carried out and mitochondrial cytochrome oxidase I gene (mtCOI) sequences were compared for allopatric and sympatric Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) populations collected from Africa and India, and from the host‐plants cassava, sweet‐potato and a common weed, Euphorbia geniculata. Three incompatible mating groups were discovered, which involved the cassava B. tabaci colonies from Africa and India, the cassava and sweet‐potato B. tabaci populations from Uganda, and the cassava and E. geniculata B. tabaci from India. Successful reciprocal mating occurred between cassava‐specific B. tabaci from Uganda, Tanzania and Ghana, and between two Indian cassava B. tabaci populations. The parsimony and neighbour‐joining analyses of 699 bp mtCOI gene sequences divided the colonies primarily into those originating from Africa and India. Further subgrouping corresponded to host‐plant specialization. Cassava‐specific Ugandan, Tanzanian and Ghanaian colonies formed a single group and the sympatric sweet‐potato colony from Uganda grouped separately from them. The two geographically distant Indian cassava B. tabaci populations were similar and formed a single group, whereas the sympatric E. geniculata colony formed a sister clade. The clades generated by the phylogenetic analyses were maintained, with highly supported bootstrap values, when other published mtCOI gene sequences were included in the tree‐building process and the divisions matched those revealed by the reciprocal‐crossing experiments. These data suggest that biologically discrete populations exist within B. tabaci (sensu Russell, 1957 ).     

Vaginal Practices among Women at High Risk of HIV Infection in Uganda and Tanzania: Recorded Behaviour from a Daily Pictorial Diary

Background

Intravaginal practices (IVP) are highly prevalent in sub-Saharan African and have been implicated as risk factors for HIV acquisition. However, types of IVP vary between populations, and detailed information on IVP among women at risk for HIV in different populations is needed. We investigated IVP among women who practice transactional sex in two populations: semi-urban, facility workers in Tanzania who engage in opportunistic sex work; and urban, self-identified sex workers and bar workers in Uganda. The aim of the study was to describe and compare IVP using a daily pictorial diary.

Methodology/Principal Findings

Two hundred women were recruited from a HIV prevention intervention feasibility study in Kampala, Uganda and in North-West Tanzania. Women were given diaries to record IVP daily for six weeks. Baseline data showed that Ugandan participants had more lifetime partners and transactional sex than Tanzanian participants. Results from the diary showed that 96% of Tanzanian participants and 100% of Ugandan participants reported intravaginal cleansing during the six week study period. The most common types of cleansing were with water only or water and soap. In both countries, intravaginal insertion (e.g. with herbs) was less common than cleansing, but insertion was practiced by more participants in Uganda (46%) than in Tanzania (10%). In Uganda, participants also reported more frequent sex, and more insertion related to sex. In both populations, cleansing was more often reported on days with reported sex and during menstruation, and in Uganda, when participants experienced vaginal discomfort. Participants were more likely to cleanse after sex if they reported no condom use.

Conclusions

While intravaginal cleansing was commonly practiced in both cohorts, there was higher frequency of cleansing and insertion in Uganda. Differences in IVP were likely to reflect differences in sexual behaviour between populations, and may warrant different approaches to interventions targeting IVP. Vaginal practices among women at high risk in Uganda and Tanzania: recorded behaviour from a daily pictorial diary.     

Endophytic nifH gene diversity in African sweet potato

A cultivation-independent approach was used to identify potentially nitrogen-fixing endophytes in seven sweet potato varieties collected in Uganda and Kenya. Nitrogenase reductase genes (nifH) were amplified by PCR, and amplicons were cloned in Escherichia coli. Clones were grouped by restriction fragment length polymorphism analysis, and representative nifH genes were sequenced. The resulting sequences had high homologies to nitrogenase reductases from alpha-, beta-, and gamma-Proteobacteria and low G+C Gram positives, however, about 50% of the sequences derived from rhizobia. Several highly similar or even identical nitrogenase reductase sequences clustering with different bacterial genera and species, including Sinorhizobium meliloti, Rhizobium sp. NGR234, Rhizobium etli, Klebsiella pneumoniae, and Paenibacillus odorifer, could be detected in different plants grown in distinct geographic locations. This suggests that these bacterial species preferentially colonize African sweet potato as endophytes and that the diazotrophic, endophytic microflora is determined only to a low degree by the plant genotype or the soil microflora.     

Soil Fungal Diversity and Community Composition in Response to Continuous Sweet Potato Cropping Practices

Soil fungi are extremely important for maintaining soil health and plant production in agricultural systems. Currently, the effect of continuous cropping of sweet potato on soil fungal communities and physiochemical parameters has not been well documented. In the present study, four sweet potato fields consecutively monocultured for 1, 2, 3, and 4 years were selected to investigate the effect of monoculture on soil fungal communities through Illumina MiSeq sequencing. Continuous cropping of sweet potatoes dramatically altered the fungal community composition, whereas fungal diversity was almost unchanged. Ascomycota and Basidiomycota were the most abundant phyla in all soil samples, accounting for 32.59% and 21.14% of the average relative abundance, respectively. The abundance of some potential pathogens, such as Ascobolus spp, specifically Ascobolus stercorarius, and some unknown fungi increased significantly as the sweet potato monoculture period increased, and their presence were highly positively correlated with disease incidence. In contrast, Basidiomycota, Bullera, Fusarium and Trichocladium most likely play roles as antagonists of sweet potato disease development, as their relative abundance decreased significantly over time and were negatively correlated with disease incidence. Redundancy and correlation analyses revealed that soil pH and organic carbon content were the most important factors driving these changes. Our findings provided a dynamic overview of the fungal community and presented a clear scope for screening beneficial fungi and pathogens of sweet potato.     

Effect of Acinetobacter sp on metalaxyl degradation and metabolite profile of potato seedlings (Solanum tuberosum L.) alpha variety

One of the most serious diseases in potato cultivars is caused by the pathogen Phytophthora infestans, which affects leaves, stems and tubers. Metalaxyl is a fungicide that protects potato plants from Phytophthora infestans. In Mexico, farmers apply metalaxyl 35 times during the cycle of potato production and the last application is typically 15 days before harvest. There are no records related to the presence of metalaxyl in potato tubers in Mexico. In the present study, we evaluated the effect of Acinetobacter sp on metalaxyl degradation in potato seedlings. The effect of bacteria and metalaxyl on the growth of potato seedlings was also evaluated. A metabolite profile analysis was conducted to determine potential molecular biomarkers produced by potato seedlings in the presence of Acinetobacter sp and metalaxyl. Metalaxyl did not affect the growth of potato seedlings. However, Acinetobacter sp strongly affected the growth of inoculated seedlings, as confirmed by plant length and plant fresh weights which were lower in inoculated potato seedlings (40% and 27%, respectively) compared to the controls. Acinetobacter sp also affected root formation. Inoculated potato seedlings showed a decrease in root formation compared to the controls. LC-MS/MS analysis of metalaxyl residues in potato seedlings suggests that Acinetobacter sp did not degrade metalaxyl. GC-TOF-MS platform was used in metabolic profiling studies. Statistical data analysis and metabolic pathway analysis allowed suggesting the alteration of metabolic pathways by both Acinetobacter sp infection and metalaxyl treatment. Several hundred metabolites were detected, 137 metabolites were identified and 15 metabolic markers were suggested based on statistical change significance found with PLS-DA analysis. These results are important for better understanding the interactions of putative endophytic bacteria and pesticides on plants and their possible effects on plant metabolism.     

Nutritional characterization of some tropical urban market crop wastes

Market crop wastes of banana (Musa acuminata) leaves and pseudo-stem sheaths, sweet potato (Ipomoea batatas) vines and Solanum aethiopicum (traditionally known as nakati) were collected from three major markets in Kampala (Uganda). The wastes were evaluated for chemical composition during the dry and wet seasons, rumen degradation using three cannulated indigenous mature ewes, and digestibility using 12 indigenous intact growing male goats, 4–6 months old and weighing 15.8 kg (S.D. 2.1). The goats in the digestibility study were kept in metabolism cages and fed the wastes as sole diets, either fresh or wilted.

Mean dry matter (DM) content was 97, 121, 197 and 216 g/kg for pseudo-stem sheaths, nakati, sweet potato vines and banana leaves, respectively. Crude protein (CP) was 34, 109, 112 and 114 g/kg DM for pseudo-stem sheaths, banana leaves, sweet potato vines and nakati, respectively. The chemical composition was similar among seasons and markets for the banana based wastes. However, for sweet potato vines and nakati, the wet season wastes had significantly higher CP and lower NDFom and ADFom. Chemical composition was different (P<0.05) among the markets for nakati. Effective degradability differed (P<0.05) between the wastes, averaging 0.43 (banana leaves), 0.47 (pseudo-stem sheaths) and 0.56 (nakati) to 0.69 g/g DM incubated (sweet potato vines). DM intake, N retention and digestibility were not significantly affected by wilting. Average DM intake was 176, 270 and 559 g/day; CP intake was 26, 30 and 63 g/day, while metabolizable energy (ME) intake was 1.3, 1.7 and 5.1 MJ/day for nakati, banana leaves and sweet potato vines, respectively. N retention (as a fraction of N intake) was −0.51 (banana leaves), 0.62 (nakati) and 0.39 (sweet potato vines). The organic matter (OM) and CP digestibilities of banana leaves were low, averaging 0.52 and 0.49, respectively. The high moisture content of nakati wastes resulted in low intake, whereas banana leaves had a low degradation rate and a low N retention. Market sweet potato vine wastes were sufficient to provide the CP and ME required by growing goats under tropical conditions.     

细胞和分子技术在甘薯茎线虫病抗病育种中的应用

甘薯茎线虫病是我国北方甘薯薯区的重要病害之一。为进一步研究甘薯茎线虫病育种中线虫和甘薯的抗感关系,利用细胞培养技术建立发根农杆菌转化甘薯发根,用该发根培养马铃薯腐烂线虫,构建植物寄生线虫培养和抗性鉴定的技术平台;用聚合酶链式反应(polymerase chain reaction,PCR)分子标记技术筛选甘薯茎线虫病抗感品种的分子标记,并对发根培养马铃薯腐烂线虫体系和分子标记辅助选择抗甘薯茎线虫病品种技术进行了展望。     

Genetic diversity of traditional South American Landraces of Cassava (Manihot esculenta Crantz): an analysis using microsatellites

The extent and structure of the genetic variability of traditional varieties of cassava (Manihot esculenta Crantz) have been little documented, despite considerable evidence for this crop? great varietal diversity in traditional agroecosystems. We used microsatellite markers to assess the genetic structure of traditional landraces of sweet and bitter cassava collected from five South American sites. As reference, we used a sample of 38 accessions from a world collection of cultivated cassava. For a total of 10 loci examined, we found 15 alleles that were not represented in this sample. Ten of these had been previously detected in wild Manihot species. The geographical structure of genetic variability was weak, but the genetic differentiation between bitter and sweet landraces was significant, suggesting that each form had evolved separately after domestication. Our results showed that traditional landraces form an important source of genetic diversity and merit more attention from managers of crop genetic resources.     

Rift Valley fever knowledge,mitigation strategies and communication preferences among male and female livestock farmers in Eastern Province,Rwanda

The Government of Rwanda reported an outbreak of Rift Valley fever (RVF) in the Eastern Province in 2018. To respond to the outbreak, vaccination and education campaigns about the disease were carried out. Because RVF cases continue to be detected in Rwanda and the disease impacts livelihoods and health, accurate knowledge and communication are imperative. The objectives of this study were to evaluate knowledge and risk perceptions of RVF transmission among livestock farmers in Nyagatare District, Eastern Province, Rwanda, and to compare RVF knowledge, risk perceptions, and farming practices between male and female livestock farmers. This cross-sectional, quantitative study was conducted in selected sectors of Nyagatare District in the Eastern Province of Rwanda in June 2019. A 34-question survey was used to ask about demographics, livestock ownership, risk perceptions about zoonotic diseases and livestock management, RVF knowledge, preferred communication sources and information sharing strategies, and protective strategies for RVF mitigation while working with livestock. Livestock farmers were interviewed at three milk collection centers, two village meeting points, a farm cooperative meeting, and during door-to-door visits in villages. In total, 123 livestock farmers were interviewed. The survey found that most livestock farmers lacked knowledge about epizootic and zoonotic transmission of RVF, more male livestock farmers were familiar with RVF and risk mitigation strategies, and female livestock farmers are not viewed as reliable sources of information. Additionally, most livestock farmers had not vaccinated their animals against RVF despite past vaccination campaigns. Radio was the most popular communication channel. These findings show that RVF knowledge and information sharing are inadequate among livestock farmers in Eastern Province. Therefore, vaccination and education campaigns may need to be reevaluated within the context of these trends in order to prepare for future RVF outbreaks.