Farmers’ selection cues in cowpea for vegetable use in eastern Uganda

A participatory cowpea varietal selection was carried out in Eastern Uganda in Kumi district among farmers (n=30) in the sub-Counties of: Ongino, Kumi and Kanyum. A range of opinions were collected to identify farmers’ selection criteria based on different sensory attributes and their most preferred genotypes for vegetable use. A preference analysis was carried out to obtain quantitative preference scores of each plot. This was followed by organoleptic tests which included attributes like taste, aroma and texture of the genotypes at the vegetative and immature R4 stages. Focus group discussions (FGDs) were also held to find consensus of the independent evaluations made by individual farmers. Data for sixteen (16) cowpea genotypes were collected at the different above mentioned stages. Quantitative data were analyzed based on farmers’ scores made on the different evaluated attributes and ANOVA was used to provide mean differences between location, gender and genotype at a significant level of 5%. Preference score for each of the varieties tested was determined and presented. Data from FGDs were grouped, similarities and differences were later determined depending on their level of importance to the farmers. Significant differences (p<0.05) in farmer choices were observed for leaf taste, immature pod aroma, taste and texture; mature pod aroma, taste between farmer groups, age genotype and gender. Irrespective of age, gender, farmer group and genotype, farmers seemed to give more importance to the smooth texture, little hard leaves when chewing, sweet taste with a mild aroma (leaves) and a moderate aroma (pods). Majority (9%) of the farmers preferred Ebelat (landrace) at V4 stage; this was followed by Danila (8.7%). On the other hand, UCUCOW1 (13% at immature and 10.2% at mature cooked R4 stage) followed by Ebelat (9% and 9.8% for immature and mature R4 stage, respectively) were preferred by majority of the farmers. In terms of sensory attributes, farmers preferred genotypes with sweet taste, moderate aroma and tender texture. The information is a baseline for understanding key farmer selection criteria in utilization of cowpea as a vegetable which can be used in generating a demand-led variety design for the crop.&nbsp

Farmers’ selection cues in cowpea for vegetable use in eastern Uganda

This is a research article on participatory cowpea varietal selection was carried out in Eastern Uganda in Kumi district among farmersA participatory cowpea varietal selection was carried out in Eastern Uganda in the Kumi district among farmers (n=30) in the sub-Counties of Ongino, Kumi and Kanyum. An arange of opinions were collected to identify farmers’ selection criteria based on different sensory attributes and their most preferred genotypes for vegetable use. A Apreference analysis was carried out to obtain quantitative preference scores of each plot. This was followed by organoleptic tests which included attributes like taste, aroma and texture of the genotypes at the vegetative and immature R4 stages. Focus group discussions (FGDs) were also held to find a consensus of the independent evaluations made by individual farmers. Data for sixteen (16) cowpea genotypes were collected at the different above-mentioned stages. Quantitative data were analyzed based on farmers’ scores made on the different evaluated attributes and ANOVA was used to provide mean differences between location, gender and genotype at a significant level of 5%. The preference score for each of the varieties tested was determined and presented. Data from FGDs were grouped, similarities and differences were later determined depending on their level of importance to the farmers. Significant differences (p<0.05) in farmer choices were observed for leaf taste, immature pod aroma, taste and texture; mature pod aroma, taste between farmer groups, age genotype and gender. Irrespective of age, gender, farmer group and genotype, farmers seemed to give more importance to the smooth texture, little hard leaves when chewing, sweet taste with a mild aroma (leaves) and a moderate aroma (pods). Majority (9%) of the farmers preferred Ebelat (landrace) at V4 stage; this was followed by Danila (8.7%). On the other hand, UCUCOW1 (13% at immature and 10.2% at mature cooked R4 stage) followed by Ebelat (9% and 9.8% for immature and mature R4 stage, respectively) were preferred by the majority of the farmers. In terms of sensory attributes, farmers preferred genotypes with a sweet taste, moderate aroma and tender texture. The information is a baseline for understanding key farmer selection criteria in the utilization of cowpea as a vegetable which can be used in generating a demand-led variety design for the crop

A genome scan for quantitative trait loci affecting cyanogenic potential of cassava root in an outbred population

<p>Abstract</p> <p>Background</p> <p>Cassava (<it>Manihot esculenta </it>Crantz) can produce cyanide, a toxic compound, without self-injury. That ability was called the cyanogenic potential (CN). This project aimed to identify quantitative trait loci (QTL) associated with the CN in an outbred population derived from 'Hanatee' × 'Huay Bong 60', two contrasting cultivars. CN was evaluated in 2008 and in 2009 at Rayong province, and in 2009 at Lop Buri province, Thailand. CN was measured using a picrate paper kit. QTL analysis affecting CN was performed with 303 SSR markers.</p> <p>Results</p> <p>The phenotypic values showed continuous variation with transgressive segregation events with more (115 ppm) and less CN (15 ppm) than either parent ('Hanatee' had 33 ppm and 'Huay Bong 60' had 95 ppm). The linkage map consisted of 303 SSR markers, on 27 linkage groups with a map that encompassed 1,328 cM. The average marker interval was 5.8 cM. Five QTL underlying CN were detected. <it>CN08R1</it>from 2008 at Rayong, <it>CN09R1</it>and <it>CN09R2 </it>from 2009 at Rayong, and <it>CN09L1 </it>and <it>CN09L2 </it>from 2009 at Lop Buri were mapped on linkage group 2, 5, 10 and 11, respectively. Among all the identified QTL, <it>CN09R1 </it>was the most significantly associated with the CN trait with LOD score 5.75 and explained the greatest percentage of phenotypic variation (%Expl.) of 26%.</p> <p>Conclusions</p> <p>Five new QTL affecting CN were successfully identified from 4 linkage groups. Discovery of these QTL can provide useful markers to assist in cassava breeding and studying genes affecting the trait.</p

Intensive Case Finding and Isoniazid Preventative Therapy in HIV Infected Individuals in Africa: Economic Model and Value of Information Analysis

Background: Tuberculosis (TB) accounts of much of the morbidity and mortality associated with HIV. We evaluate the costeffectiveness of different strategies to actively screen for TB disease in HIV positive individuals, where isoniazid preventative therapy (IPT) is given to those screening negative, and use value of information analysis (VOI) to identify future research priorities. Methodology / Principal Findings: We built an individual sampling model to investigate the costs (2010 US Dollars) and consequences of screening for TB, and providing TB treatment or IPT in adults testing HIV positive in Sub-Saharan Africa. A systematic review and meta-analysis was conducted to assess performance of the nine different TB screening strategies evaluated. Probabilistic sensitivity analysis was conducted to incorporate decision uncertainty, and expected value of perfect information for the entire model and for groups of parameters was calculated. Screening all HIV infected individuals with sputum microscopy was the least costly strategy, with other strategies not cost-effective at WHO recommended thresholds. Screening those with TB symptoms with sputum microscopy and CXR would be cost-effective at a threshold ICER of $7,800 per quality-adjusted life year (QALY), but associated with significant uncertainty. VOI analysis suggests further information would be of value. Conclusions / Significance: Resource-constrained countries in sub-Saharan Africa wishing to scale up TB preventativ

Treatment-seeking behaviour in low- and middle-income countries estimated using a Bayesian model

Background: Seeking treatment in formal healthcare for uncomplicated infections is vital to combating disease in low- and middle-income countries (LMICs). Healthcare treatment-seeking behaviour varies within and between communities and is modified by socio-economic, demographic, and physical factors. As a result, it remains a challenge to quantify healthcare treatment-seeking behaviour using a metric that is comparable across communities. Here, we present an application for transforming individual categorical responses (actions related to fever) to a continuous probabilistic estimate of fever treatment for one country in Sub-Saharan Africa (SSA).Methods: Using nationally representative household survey data from the 2013 Demographic and Health Survey (DHS) in Namibia, individual-level responses (n = 1138) were linked to theoretical estimates of travel time to the nearest public or private health facility. Bayesian Item Response Theory (IRT) models were fitted via Markov Chain Monte Carlo (MCMC) simulation to estimate parameters related to fever treatment and estimate probability of treatment for children under five years. Different models were implemented to evaluate computational needs and the effect of including predictor variables such as rurality. The mean treatment rates were then estimated at regional level.Results: Modelling results suggested probability of fever treatment was highest in regions with relatively high incidence of malaria historically. The minimum predicted threshold probability of seeking treatment was 0.3 (model 1: 0.340; 95% CI 0.155–0.597), suggesting that even in populations at large distances from facilities, there was still a 30% chance of an individual seeking treatment for fever. The agreement between correctly predicted probability of treatment at individual level based on a subset of data (n = 247) was high (AUC = 0.978), with a sensitivity of 96.7% and a specificity of 75.3%.Conclusion: We have shown how individual responses in national surveys can be transformed to probabilistic measures comparable at population level. Our analysis of household survey data on fever suggested a 30% baseline threshold for fever treatment in Namibia. However, this threshold level is likely to vary by country or endemicity. Although our focus was on fever treatment, the methodology outlined can be extended to multiple health seeking behaviours captured in routine national survey data and to other infectious diseases.<br/