Development of sequence characterized amplified region (SCAR) markers linked to race-specific resistance to Striga gesnerioides in cowpea (Vigna unguiculata L.)

An amplified fragement length polymorphism (AFLP) fragment, E-ACT/M-CAA524, tightly linked to the Striga gesnerioides race 1 (SG1) resistance gene Rsg-2-1 in cowpea (Vigna unguiculata L.) was isolated by polyacrylamide gel electrophoresis, cloned, and its nucleotide sequence determined. Based on the resulting sequence information, a pair of sequence specific primers were designed and used to isolate identical and similar fragments from cowpea genomic DNA of different cowpea lines by polymerase chain reaction (PCR) amplification. The primers amplified a ~500 bp fragment (SCAR marker designated as 61R) that was present in the resistant parent TVU14676, absent in susceptible parent IT84S-2246, and segregated with the resistance phenotype in an F2 population, derived from a cross of these two genotypes. The same primers were used to isolate a fragment similar to 61R from another S. gesnerioides resistant line Kvx 61-1. The sequence of this fragment was used to design a new combination of primers that developed a second SCAR marker, designated as 61R-M2. Subsequent analysis of the three markers, E-ACT/M-CAA524, 61R and 61M2 showed that they are linked to each other by 0.6 centimorgans (cM). The utility of these SCARs in marker assisted selection programs for cowpea was discussed.Keywords: Striga gesnerioides, centimorgans (cM), race specific resistance, amplified fragment length polymorphism (AFLP), sequence characterized amplified region (SCAR), marker assisted selection (MAS

Aperçu de la culture du voandzou (Vigna subterranea (L.) Verdcourt) au Burkina Faso: enjeux et perspectives d’amélioration de sa productivité

Le voandzou constitue avec le niébé, les deux principales légumineuses alimentaires pour de nombreuses populations rurales et la frange pauvre des citadins au Burkina Faso. Cependant, des informations émanant de l’environnement de production de cette culture selon la perception des producteurs sont quasi inexistantes. Cette étude vise à s’informer au mieux des réalités sociales, environnementales et techniques qui entourent la production de cette culture. Les données collectées auprès des producteurs à l’aide des fiches d’enquêtes ont été soumises à une analyse fréquentielle. La culture du voandzou est pratiquée majoritairement par les femmes sur des petites superficies sans apport de fertilisants. Les maladies foliaires et les insectes de stock constituent les principales contraintes biotiques. Les producteurs conservent la semence dans des bidons fermés hermétiquement. Le cycle moyen des variétés cultivées est de 90 jours. La variété préférée est celle de couleur crème à hile blanc pour ses qualités organoleptiques, agronomiques et esthétiques. Le manque de sensibilisation sur la qualité nutritionnelle de la culture, l’insuffisance d’activités de recherche sur les techniques innovantes pour améliorer son système de production et les contraintes biotiques et abiotiques expliquent en grande partie la faible productivité et production de cette culture.© 2016 International Formulae Group. All rights reserved.Mots clés: Culture, Voandzou, Burkina Faso, productivitéEnglish Title:  Overview of the culture of bambara groundnut (Vigna subterranea (L.) Verdcourt) in Burkina Faso : Issues and prospects for improving its productivityEnglish AbstractBambara groundnut is, with cowpea, the two main food legumes for many rural and poor urban fringes in Burkina Faso. However, information from the production environment of this culture as perceived by  producers is almost nonexistent. This study aims at collecting information about social, environmental and technical realities surrounding the production of this crop. The data collected from producers using survey forms were subjected to a frequency analysis. Bambara groundnut cultivation is mainly practiced by women on small areas without adding fertilizers. Foliar diseases and insects in stock are major biotic constraints. Producers retain the seed in cans tightly closed. The average cycle of cultivated varieties is 90 days. The favorite variety is the cream-colored white hilum for its organoleptic, agronomic and aesthetic qualities. Lack of awareness on the nutritional quality of culture, the lack of research on innovative techniques to improve its production system and the biotic and abiotic constraints largely explain the low productivity and production of this crop.© 2016 International Formulae Group. All rights reserved.Keywords: Culture, Bambara groundnut, Burkina Faso, productivit

Post-Harvest Management Practices Of Bambara Groundnut (Vigna Subterranea (L.) Verdc) Seeds In Burkina Faso

Bambara groundnut plays a major role in the production systems and diets of farmers in Burkina Faso. This crop, due to certain production, storage, or preservation conditions, is subject to damage by insects and fungi. Effective post-harvest management can contribute significantly to reducing losses during storage. This study was carried out in the three agro-ecological areas in Burkina Faso to assess post-harvest management practices of Bambara groundnut among farmers. The data were collected from 180 farmers using surveys. The results showed that the culture of Bambara groundnut was mainly carried out by women (74.4%) on small farms (0.25-0.5ha). The harvested crops were dried at home during a period of 5 to 14 days. About 53% of farmers stored seeds for more than 3 months. Seeds were mainly stored in hermetically sealed cans (45.6%) and in plastic bags (31.1%). Some products such as wood ash and chemicals were used for seed storage. Challenges during seed storage were insects (91.4%) and fungi (42.9%). In the case of seeds attacked by pests (insects, fungi, etc.), farmers (84.4%) adopt a set of measures consisting of sorting, winnowing, drying, and repackaging the seeds. Besides the existence of traditional storage techniques, there is still a need to develop effective storage techniques and continue building farmers’ awareness on improved storage technologies to avoid post-harvest losses

ANALYZING SMALLHOLDERS AGRICULTURAL COMMERCIALIZATION IN BURKINA FASO. THE ROLE OF TRANSACTION COSTS AND HOUSEHOLDS ASSETS

Promoting smallholders’ agricultural commercialization is frequently identified as a promising strategy to improve agricultural contribution to poverty reduction and economic growth in developing countries. This paper analyses the determinants of agricultural commercialization of smallholder farmers in Burkina Faso, focusing on the role of transaction costs and households’ productive resources. Based on data collected in 2011 at national level from a sample of 1178 farm households, a double hurdle model of market participation and intensity of participation measured by crop commercialization index is estimated. The results indicate that households’ productive resources such as farm size per worker, use of animal traction, quantity of fertilizer used per hectare and access to credit significantly increase the likelihood of households’ market participation and the intensity of commercialization. In addition, transaction costs factors such as quality of rural roads and ownership of communication assets have positive and significant effects on the probability of market participation. Therefore, reducing remoteness-induced transaction costs by unlocking rural areas and improving farm households’ access to productive assets and technologies are required to promote agricultural transformation and commercialization of smallholder farmers

Coping with climate variability and change in research for development targeting West Africa: Need for paradigm changes

Climate change and variability impact on agriculture in the West African Semi-Arid Tropics (WASAT). At present WASAT farmers are most concerned by climate variability which shows the greatest consequences towards the northern drier end of the region. Relative variability, number of existential droughts, species loss and variety turnover are highest there. This paper presents experiences made and approaches developed in the framework of a Research for Development (R4D) project aiming at preparing WASAT farmers to deal with climate constraints. It is argued that agro-phytodiversity management is a reasonable approach to deal with climate variability but that it needs better social organisation to conserve a sufficient number of crops and varieties. Optimised participation and empowerment of farmers in the R4D continuum leads to faster progress with respect to innovation testing, adaptation and sustainable adoption

Yield and leafspot response of interspecific peanut crosses in early generation tests

Vita.Seven interspecific peanut (Arachis hypogaea L.) lines and Southern Runner were crossed in a half-diallel. The F, , F2, and F, progenies were evaluated for early leafspot reaction and yield. The objectives of the study were: 1) to determine the predictability in F, and F2 generations of crosses most likely to give the greatest expression of early leafspot resistance and yield; 2) to assess the genetic response due to early generation selection; 3) to compare alternative methods of selection for early leafspot resistance; and 4) to assess the use of molecular markers (RAPD) for selection for leafspot resistance. Disease assessment was made using the Florida leafspot rating scale at I 10 and 130 days after planting, and determinations were made for lesion diameter, amount of sporulation, and latent period in both the field and laboratory. Genetic analysis was performed using the Griffing method 2 model 1. Significant differences existed among crosses for the visual leafspot rating, latent period, and amount of sporulation in the F2 generation (P = 0.05). Pod yield, based on individual plants, differed significantly among the F2 crosses, but not in the F, (P = 0.05). Little heterosis was found among these F, crosses. Performance of the F , was not reflected in the F2, as rank correlation between the two populations for pod yield was low (r = 0.32) and not significant (P = 0.05). Combining ability effects (both general and specific) were significant for yield and disease parameters in the F2 and F3 generations. In a preliminary study, 60 primers out of 200 tested yielded 103 bands of size generally less than 1,900 bp. Analysis of the banding pattern revealed a higher incidence of polymorphism between A. hypogaea and A. cardenasii Krapov and W.C. Gregory and A. diogoi Hoehne respectively, than between A. hypogaea and the advanced interspecific lines. The results indicated that DNA segments were successfully transferred from the wild species to the cultivated A. hypogaea and that genetic diversity in peanut can be assessed using RAPD markers. Evidence of association between any of these RAPD markers to early leafspot resistance or any trait of interest was not established in this study

Yield and leafspot response of interspecific peanut crosses in early generation tests

Vita.Seven interspecific peanut (Arachis hypogaea L.) lines and Southern Runner were crossed in a half-diallel. The F, , F2, and F, progenies were evaluated for early leafspot reaction and yield. The objectives of the study were: 1) to determine the predictability in F, and F2 generations of crosses most likely to give the greatest expression of early leafspot resistance and yield; 2) to assess the genetic response due to early generation selection; 3) to compare alternative methods of selection for early leafspot resistance; and 4) to assess the use of molecular markers (RAPD) for selection for leafspot resistance. Disease assessment was made using the Florida leafspot rating scale at I 10 and 130 days after planting, and determinations were made for lesion diameter, amount of sporulation, and latent period in both the field and laboratory. Genetic analysis was performed using the Griffing method 2 model 1. Significant differences existed among crosses for the visual leafspot rating, latent period, and amount of sporulation in the F2 generation (P = 0.05). Pod yield, based on individual plants, differed significantly among the F2 crosses, but not in the F, (P = 0.05). Little heterosis was found among these F, crosses. Performance of the F , was not reflected in the F2, as rank correlation between the two populations for pod yield was low (r = 0.32) and not significant (P = 0.05). Combining ability effects (both general and specific) were significant for yield and disease parameters in the F2 and F3 generations. In a preliminary study, 60 primers out of 200 tested yielded 103 bands of size generally less than 1,900 bp. Analysis of the banding pattern revealed a higher incidence of polymorphism between A. hypogaea and A. cardenasii Krapov and W.C. Gregory and A. diogoi Hoehne respectively, than between A. hypogaea and the advanced interspecific lines. The results indicated that DNA segments were successfully transferred from the wild species to the cultivated A. hypogaea and that genetic diversity in peanut can be assessed using RAPD markers. Evidence of association between any of these RAPD markers to early leafspot resistance or any trait of interest was not established in this study

Yield, grade, and leafspot reaction of interspecific derived peanut lines

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