Genotype evaluation of cowpea seeds (Vigna unguiculata) using 1H qNMR combined with exploratory tools and solid-state NMR.

Science.gov (United States)

Alves Filho, Elenilson G; Silva, Lorena M A; Teofilo, Elizita M; Larsen, Flemming H; de Brito, Edy S

2017-01-01

The ultimate aim of this study was to apply a non-targeted chemometric analysis (principal component analysis and hierarchical clustering analysis using the heat map approach) of NMR data to investigate the variability of organic compounds in nine genotype cowpea seeds, without any complex pre-treatment. In general, both exploratory tools show that Tvu 233, CE-584, and Setentão genotypes presented higher amount mainly of raffinose and Tvu 382 presented the highest content of choline and least content of raffinose. The evaluation of the aromatic region showed the Setentão genotype with highest content of niacin/vitamin B3 whereas Tvu 382 with lowest amount. To investigate rigid and mobile components in the seeds cotyledon, 13 C CP and SP/MAS solid-state NMR experiments were performed. The cotyledon of the cowpea comprised a rigid part consisting of starch as well as a soft portion made of starch, fatty acids, and protein. The variable contact time experiment suggests the presence of lipid-amylose complexes. Copyright © 2016 Elsevier Ltd. All rights reserved.

Symbiotic functioning and bradyrhizobial biodiversity of cowpea (Vigna unguiculata L. Walp. in Africa

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Dakora Felix D

2010-03-01

Full Text Available Abstract Background Cowpea is the most important food grain legume in Sub-Saharan Africa. However, no study has so far assessed rhizobial biodiversity and/or nodule functioning in relation to strain IGS types at the continent level. In this study, 9 cowpea genotypes were planted in field experiments in Botswana, South Africa and Ghana with the aim of i trapping indigenous cowpea root-nodule bacteria (cowpea "rhizobia" in the 3 countries for isolation, molecular characterisation using PCR-RFLP analysis, and sequencing of the 16S - 23S rDNA IGS gene, ii quantifying N-fixed in the cowpea genotypes using the 15N natural abundance technique, and iii relating the levels of nodule functioning (i.e. N-fixed to the IGS types found inside nodules. Results Field measurements of N2 fixation revealed significant differences in plant growth, δ15N values, %Ndfa and amounts of N-fixed between and among the 9 cowpea genotypes in Ghana and South Africa. Following DNA analysis of 270 nodules from the 9 genotypes, 18 strain IGS types were found. Relating nodule function to the 18 IGS types revealed significant differences in IGS type N2-fixing efficiencies. Sequencing the 16S - 23S rDNA gene also revealed 4 clusters, with cluster 2 forming a distinct group that may be a new Bradyrhizobium species. Taken together, our data indicated greater biodiversity of cowpea bradyrhizobia in South Africa relative to Botswana and Ghana. Conclusions We have shown that cowpea is strongly dependant on N2 fixation for its N nutrition in both South Africa and Ghana. Strain IGS type symbiotic efficiency was assessed for the first time in this study, and a positive correlation was discernible where there was sole nodule occupancy. The differences in IGS type diversity and symbiotic efficiency probably accounts for the genotype × environment interaction that makes it difficult to select superior genotypes for use across Africa. The root-nodule bacteria nodulating cowpea in this study

Genomic Tools in Cowpea Breeding Programs: Status and Perspectives

Science.gov (United States)

Boukar, Ousmane; Fatokun, Christian A.; Huynh, Bao-Lam; Roberts, Philip A.; Close, Timothy J.

2016-01-01

Cowpea is one of the most important grain legumes in sub-Saharan Africa (SSA). It provides strong support to the livelihood of small-scale farmers through its contributions to their nutritional security, income generation and soil fertility enhancement. Worldwide about 6.5 million metric tons of cowpea are produced annually on about 14.5 million hectares. The low productivity of cowpea is attributable to numerous abiotic and biotic constraints. The abiotic stress factors comprise drought, low soil fertility, and heat while biotic constraints include insects, diseases, parasitic weeds, and nematodes. Cowpea farmers also have limited access to quality seeds of improved varieties for planting. Some progress has been made through conventional breeding at international and national research institutions in the last three decades. Cowpea improvement could also benefit from modern breeding methods based on molecular genetic tools. A number of advances in cowpea genetic linkage maps, and quantitative trait loci associated with some desirable traits such as resistance to Striga, Macrophomina, Fusarium wilt, bacterial blight, root-knot nematodes, aphids, and foliar thrips have been reported. An improved consensus genetic linkage map has been developed and used to identify QTLs of additional traits. In order to take advantage of these developments single nucleotide polymorphism (SNP) genotyping is being streamlined to establish an efficient workflow supported by genotyping support service (GSS)-client interactions. About 1100 SNPs mapped on the cowpea genome were converted by LGC Genomics to KASP assays. Several cowpea breeding programs have been exploiting these resources to implement molecular breeding, especially for MARS and MABC, to accelerate cowpea variety improvement. The combination of conventional breeding and molecular breeding strategies, with workflow managed through the CGIAR breeding management system (BMS), promises an increase in the number of improved

Genomic tools in cowpea breeding programs: status and perspectives

Directory of Open Access Journals (Sweden)

Ousmane eBoukar

2016-06-01

Full Text Available Cowpea is one of the most important grain legumes in sub-Saharan Africa (SSA. It provides strong support to the livelihood of small-scale farmers through its contributions to their nutritional security, income generation and soil fertility enhancement. Worldwide about 6.5 million metric tons of cowpea are produced annually on about 14.5 million hectares. The low productivity of cowpea is attributable to numerous abiotic and biotic constraints. The abiotic stress factors comprise drought, low soil fertility, and heat while biotic constraints include insects, diseases, parasitic weeds and nematodes. Cowpea farmers also have limited access to quality seeds of improved varieties for planting. Some progress has been made through conventional breeding at international and national research institutions in the last three decades. Cowpea improvement could also benefit from modern breeding methods based on molecular genetic tools. A number of advances in cowpea genetic linkage maps, and quantitative trait loci associated with some desirable traits such as resistance to Striga, Macrophomina, Fusarium wilt, bacterial blight, root-knot nematodes, aphids and foliar thrips have been reported. An improved consensus genetic linkage map has been developed and used to identify QTLs of additional traits. In order to take advantage of these developments single nucleotide polymorphism (SNP genotyping is being streamlined to establish an efficient workflow supported by genotyping support service (GSS-client interactions. About 1100 SNPs mapped on the cowpea genome were converted by LGC Genomics to KASP assays. Several cowpea breeding programs have been exploiting these resources to implement molecular breeding, especially for MARS and MABC, to accelerate cowpea variety improvement. The combination of conventional breeding and molecular breeding strategies, with workflow managed through the CGIAR breeding management system (BMS, promises an increase in the number of

interactive effect of cowpea variety, dose and exposure time

African Journals Online (AJOL)

ACSS

Callosobruchus maculatus has for years remained a serious menace in cowpea in Sub-Sahara Africa. The objective of this study was to investigate the effect of genotypic cowpea (Vigna unguiculata (L.) Walp) varieties, time and dose on C. maculatus exposed to powders of Piper guineense and Eugenia aromatica.

nature of resistance of cowpea alectra vogelii infestation abstract ...

African Journals Online (AJOL)

USER

The objective of this study was to identify the type of gene action controlling the trait for resistance to. Alectra vogelii in cowpea and estimate the heritability of the trait. Seven genotypes of cowpea were mated in half diallel and their F2 progeny, including parents, were evaluated for reaction to Alectra vogelii infection in the ...

Nature of resistance of cowpea Alectra vogelii infestation | Mbwando ...

African Journals Online (AJOL)

The objective of this study was to identify the type of gene action controlling the trait for resistance to Alectra vogelii in cowpea and estimate the heritability of the trait. Seven genotypes of cowpea were mated in half diallel and their F2 progeny, including parents, were evaluated for reaction to Alectra vogelii infection in the ...

Cowpea Nodules Harbor Non-rhizobial Bacterial Communities that Are Shaped by Soil Type Rather than Plant Genotype

OpenAIRE

Leite, Jakson; Fischer, Doreen; Rouws, Luc F. M.; Fernandes-J?nior, Paulo I.; Hofmann, Andreas; Kublik, Susanne; Schloter, Michael; Xavier, Gustavo R.; Radl, Viviane

2017-01-01

Many studies have been pointing to a high diversity of bacteria associated to legume root nodules. Even though most of these bacteria do not form nodules with legumes themselves, it was shown that they might enter infection threads when co-inoculated with rhizobial strains. The aim of this work was to describe the diversity of bacterial communities associated with cowpea (Vigna unguiculata L. Walp) root nodules using 16S rRNA gene amplicon sequencing, regarding the factors plant genotype and ...

Genetic analysis of seed proteins contents in cowpea ( Vigna ...

African Journals Online (AJOL)

In order to select cowpea genotypes with high food value, 10 varieties were genetically screened in Ngaoundéré (Cameroon) for seed crude protein and its soluble fractions contents. Five divergent lines were studied through a 5 x 5 half diallel cross mating. The genotypes presented a significant genetic variability for these ...

Genetic parameters and path analysis in cowpea genotypes grown in the Cerrado/Pantanal ecotone.

Science.gov (United States)

Lopes, K V; Teodoro, P E; Silva, F A; Silva, M T; Fernandes, R L; Rodrigues, T C; Faria, T C; Corrêa, A M

2017-05-18

Estimating genetic parameters in plant breeding allows us to know the population potential for selecting and designing strategies that can maximize the achievement of superior genotypes. The objective of this study was to evaluate the genetic potential of a population of 20 cowpea genotypes by estimating genetic parameters and path analysis among the traits to guide the selection strategies. The trial was conducted in randomized block design with four replications. Its morphophysiological components, components of green grain production and dry grain yield were estimated from genetic use and correlations between the traits. Phenotypic correlations were deployed through path analysis into direct and indirect effects of morphophysiological traits and yield components on dry grain yield. There were significant differences (P < 0.01) between the genotypes for most the traits, indicating the presence of genetic variability in the population and the possibility of practicing selection. The population presents the potential for future genetic breeding studies and is highly promising for the selection of traits dry grain yield, the number of grains per pod, and hundred grains mass. A number of grains per green pod is the main determinant trait of dry grain yield that is also influenced by the cultivar cycle and that the selection for the dry grain yield can be made indirectly by selecting the green pod mass and green pod length.

Genotype evaluation of cowpea seeds (Vigna unguiculata) using ¹H qNMR combined with exploratory tools and solid-state NMR

DEFF Research Database (Denmark)

Alves Filho, Elenilson G.; Silva, Lorena M. A.; Teofilo, Elizita M.

2017-01-01

The ultimate aim of this study was to apply a non-targeted chemometric analysis (principal component analysis and hierarchical clustering analysis using the heat map approach) of NMR data to investigate the variability of organic compounds in nine genotype cowpea seeds, without any complex pre-tr...

The damage caused by Callosobruchus maculatus on cowpea grains is dependent on the plant genotype.

Science.gov (United States)

Torres, Elida Barros; Nóbrega, Rafaela S A; Fernandes-Júnior, Paulo Ivan; Silva, Luciana Barboza; Dos Santos Carvalho, Gabriel; Marinho, Rita de Cassia Nunes; Pavan, Bruno E

2016-09-01

Beans from cowpea cultivars fertilized with mineral N or inoculated with various rhizobium strains may contain different nitrogen concentrations and nitrogen metabolite composition, which affects the beans' defense mechanisms against pests. In this study, the population growth of Callosobruchus maculatus reared on beans from four cowpea cultivars fertilized with different nitrogen sources was evaluated. The factors tested were beans from four cowpea cultivars and seven different nitrogen sources: mineral N fertilization, inoculation with five strains of symbiotic diazotrophic bacteria, and soil nitrogen (absolute control). BRS Tapaihum and BRS Acauã cultivars had lower cumulative emergence and instantaneous rate of population growth of the insects compared with other cultivars, indicating antixenosis resistance against C. maculatus. Inoculation of BRS Acauã cultivar with the diazotrophic bacteria strain BR 3299 resulted in higher mortality of C. maculatus. For BRS Tapaihum cultivar, inoculation with diazotrophic bacteria strains BR3267, BR 3262 and BR 3299, and nitrogen fertilization resulted in higher mortality among C. maculatus. BRS Tapaihum and BRS Acauã cultivars showed the lowest cumulative insect emergence and instantaneous rates of population growth, and the highest insect mortality, mainly when the grains were obtained from plants inoculated with rhizobial strains. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Gel-free/label-free proteomic, photosynthetic, and biochemical analysis of cowpea (Vigna unguiculata [L.] Walp.) resistance against Cowpea severe mosaic virus (CPSMV).

Science.gov (United States)

Varela, Anna Lidia N; Komatsu, Setsuko; Wang, Xin; Silva, Rodolpho G G; Souza, Pedro Filho N; Lobo, Ana Karla M; Vasconcelos, Ilka M; Silveira, Joaquim A G; Oliveira, Jose T A

2017-06-23

Cowpea severe mosaic virus (CPSMV) causes significant losses in cowpea (Vigna unguiculata) production. In this present study biochemical, physiological, and proteomic analysis were done to identify pathways and defense proteins that are altered during the incompatible interaction between the cowpea genotype BRS-Marataoã and CPSMV. The leaf protein extracts from mock- (MI) and CPSMV-inoculated plantlets (V) were evaluated at 2 and 6days post-inoculation (DPI). Data support the assumptions that increases in biochemical (high hydrogen peroxide, antioxidant enzymes, and secondary compounds) and physiological responses (high photosynthesis index and chlorophyll content), confirmed by label-free comparative proteomic approach, in which quantitative changes in proteasome proteins, proteins related to photosynthesis, redox homeostasis, regulation factors/RNA processing proteins were observed may be implicated in the resistance of BRS-Marataoã to CPSMV. This pioneering study provides information for the selection of specific pathways and proteins, altered in this incompatible relationship, which could be chosen as targets for detailed studies to advance our understanding of the molecular, physiological, and biochemistry basis of the resistance mechanism of cowpea and design approachs to engineer plants that are more productive. This is a pioneering study in which an incompatible relationship between a resistant cowpea and Cowpea severe mosaic virus (CPSMV) was conducted to comparatively evaluate proteomic profiles by Gel-free/label-free methodology and some physiological and biochemical parameters to shed light on how a resistant cowpea cultivar deals with the virus attack. Specific proteins and associated pathways were altered in the cowpea plants challenged with CPSMV and will contribute to our knowledge on the biological process tailored by cowpea in response to CPSMV. Copyright © 2017 Elsevier B.V. All rights reserved.

Gene Pools and the Genetic Architecture of Domesticated Cowpea

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Bao-Lam Huynh

2013-11-01

Full Text Available Cowpea [ (L. Walp.] is a major tropical legume crop grown in warm to hot areas throughout the world and especially important to the people of sub-Saharan Africa where the crop was domesticated. To date, relatively little is understood about its domestication origins and patterns of genetic variation. In this study, a worldwide collection of cowpea landraces and African ancestral wild cowpea was genotyped with more than 1200 single nucleotide polymorphism markers. Bayesian inference revealed the presence of two major gene pools in cultivated cowpea in Africa. Landraces from gene pool 1 are mostly distributed in western Africa while the majority of gene pool 2 are located in eastern Africa. Each gene pool is most closely related to wild cowpea in the same geographic region, indicating divergent domestication processes leading to the formation of two gene pools. The total genetic variation within landraces from countries outside Africa was slightly greater than within African landraces. Accessions from Asia and Europe were more related to those from western Africa while accessions from the Americas appeared more closely related to those from eastern Africa. This delineation of cowpea germplasm into groups of genetic relatedness will be valuable for guiding introgression efforts in breeding programs and for improving the efficiency of germplasm management.

Numerical and RAPD Analysis of Eight Cowpea Genotypes from ...

African Journals Online (AJOL)

Agriculture, Abeokuta, P.M.B. 2240, Abeokuta-Nigeria. (Received: ... Cowpea, Vigna unguiculata (L.) Walp is one of the world's main legumes and is an important source of ... length, 100-seed weight and seed weight per plant contributed significantly to the overall variation ... accounts for most of Africa's production, with.

Regeneration and genetic transformation of cowpea (Vigna unguiculata Walp.)

Energy Technology Data Exchange (ETDEWEB)

Filippone, E; Colucci, G; Ciardi, F; Monti, L [Department of Agronomy and Plant Genetics, Univ. of Naples Federico 11, Portici (Italy)

1997-07-01

Regeneration of cowpea (Vigna unguiculata Walp.) was achieved through massive bud formation induced in apical and lateral meristems by the herbicide Thidiazuron (TDZ). The effect of TDZ (5, 10, or 20 {mu}M) was tested in vitro on four different cowpea genotypes. Thidiazuron, even at the highest concentration, had no effect on seed germination. After one month of culture, multiple bud cluster formation was observed in all genotypes tested; about 80% of shoot apices regenerated multiple buds, whilst only 34% of cotyledonary nodes behaved in the same way. Histology of regenerating multiple bud clusters revealed that regeneration initiated from pre-existing meristems in the apex and cotyledonary node. Thidiazuron at 10 {mu}M appeared to be the best concentration to produce clusters with high number of buds, ranging from 5 to 10. Shoot elongation occurred only on MS medium without TDZ. On the same medium, 75% of elongated shoots rooted. For genetic transformation of cowpea, a direct DNA transfer methods in plants under in vivo conditions was tested by electroporation of plasmid DNA into the nodal meristematic cells. Some transformed plants were obtained, and produced T{sub 1} transformed progenies; their transgenic nature was confirmed by Southern analysis. (author). 21 refs, 2 figs, 3 tabs.

Regeneration and genetic transformation of cowpea (Vigna unguiculata Walp.)

International Nuclear Information System (INIS)

Filippone, E.; Colucci, G.; Ciardi, F.; Monti, L.

1997-01-01

Regeneration of cowpea (Vigna unguiculata Walp.) was achieved through massive bud formation induced in apical and lateral meristems by the herbicide Thidiazuron (TDZ). The effect of TDZ (5, 10, or 20 μM) was tested in vitro on four different cowpea genotypes. Thidiazuron, even at the highest concentration, had no effect on seed germination. After one month of culture, multiple bud cluster formation was observed in all genotypes tested; about 80% of shoot apices regenerated multiple buds, whilst only 34% of cotyledonary nodes behaved in the same way. Histology of regenerating multiple bud clusters revealed that regeneration initiated from pre-existing meristems in the apex and cotyledonary node. Thidiazuron at 10 μM appeared to be the best concentration to produce clusters with high number of buds, ranging from 5 to 10. Shoot elongation occurred only on MS medium without TDZ. On the same medium, 75% of elongated shoots rooted. For genetic transformation of cowpea, a direct DNA transfer methods in plants under in vivo conditions was tested by electroporation of plasmid DNA into the nodal meristematic cells. Some transformed plants were obtained, and produced T 1 transformed progenies; their transgenic nature was confirmed by Southern analysis. (author). 21 refs, 2 figs, 3 tabs

Association analysis of salt tolerance in cowpea (Vigna unguiculata (L.) Walp) at germination and seedling stages.

Science.gov (United States)

Ravelombola, Waltram; Shi, Ainong; Weng, Yuejin; Mou, Beiquan; Motes, Dennis; Clark, John; Chen, Pengyin; Srivastava, Vibha; Qin, Jun; Dong, Lingdi; Yang, Wei; Bhattarai, Gehendra; Sugihara, Yuichi

2018-01-01

This is the first report on association analysis of salt tolerance and identification of SNP markers associated with salt tolerance in cowpea. Cowpea (Vigna unguiculata (L.) Walp) is one of the most important cultivated legumes in Africa. The worldwide annual production in cowpea dry seed is 5.4 million metric tons. However, cowpea is unfavorably affected by salinity stress at germination and seedling stages, which is exacerbated by the effects of climate change. The lack of knowledge on the genetic underlying salt tolerance in cowpea limits the establishment of a breeding strategy for developing salt-tolerant cowpea cultivars. The objectives of this study were to conduct association mapping for salt tolerance at germination and seedling stages and to identify SNP markers associated with salt tolerance in cowpea. We analyzed the salt tolerance index of 116 and 155 cowpea accessions at germination and seedling stages, respectively. A total of 1049 SNPs postulated from genotyping-by-sequencing were used for association analysis. Population structure was inferred using Structure 2.3.4; K optimal was determined using Structure Harvester. TASSEL 5, GAPIT, and FarmCPU involving three models such as single marker regression, general linear model, and mixed linear model were used for the association study. Substantial variation in salt tolerance index for germination rate, plant height reduction, fresh and dry shoot biomass reduction, foliar leaf injury, and inhibition of the first trifoliate leaf was observed. The cowpea accessions were structured into two subpopulations. Three SNPs, Scaffold87490_622, Scaffold87490_630, and C35017374_128 were highly associated with salt tolerance at germination stage. Seven SNPs, Scaffold93827_270, Scaffold68489_600, Scaffold87490_633, Scaffold87490_640, Scaffold82042_3387, C35069468_1916, and Scaffold93942_1089 were found to be associated with salt tolerance at seedling stage. The SNP markers were consistent across the three models and

Foliar Desiccators Glyphosate, Carfentrazone, and Paraquat Affect the Technological and Chemical Properties of Cowpea Grains.

Science.gov (United States)

Lindemann, Igor da Silva; Lang, Gustavo Heinrich; Hoffmann, Jessica Fernanda; Rombaldi, Cesar Valmor; de Oliveira, Maurício; Elias, Moacir Cardoso; Vanier, Nathan Levien

2017-08-16

The effects of the use of glyphosate (GLY), glyphosate plus carfentrazone (GLY/CAR), and paraquat (PAR) as plant desiccators on the technological and chemical properties of cowpea grains were investigated. All studied desiccants provided lower cooking time to freshly harvested cowpea. However, the coat color of PAR- and GLY/CAR-treated cowpea was reddish in comparison to the control treatment. Principal component analysis (PCA) from liquid chromatography-mass spectrometry (LC-MS) data sets showed a clear distinction among cowpea from the different treatments. Catechin-3-glucoside and epicatechin significantly contributed for discriminating GLY-treated cowpea, while citric acid was responsible for discriminating GLY/CAR-treated cowpea. Quercetin derivative and gluconic acid were responsible for discriminating control treatment. Residual glyphosate and paraquat content was higher than the maximum limits allowed by Codex Alimentarius and the European Union Commission. Improvements in the technological and chemical properties of cowpea may not be overlapped by the risks that those desiccants exhibit when exceeding the maximum limits of tolerance in food.

NOTE - Phenotypic correlations between combining abilities of F 2 cowpea populations

Directory of Open Access Journals (Sweden)

Carolline de Jesús Pires

2012-09-01

Full Text Available Cowpea is a crop that has become socio-economically relevant, mainly in developing countries. Correlation studies are important to determine the association between quantitative traits and yield to guide the selection, i.e., choose direct or indirect selection. The objective was to estimate the correlations between six agronomic traits in cowpea as well as the correlations between the estimates of combining abilities of parents. Genotypes with high pod weight and pod length, 100-grain weight, and number of beans per pod should be used to improve grain yield in cowpea. The breeder should preferably insert plants into his group of crosses that have a high combining ability for pod length, number of grains per pod and yield per plot.

Label-free Proteomic Reveals that Cowpea Severe Mosaic Virus Transiently Suppresses the Host Leaf Protein Accumulation During the Compatible Interaction with Cowpea (Vigna unguiculata [L.] Walp.).

Science.gov (United States)

Paiva, Ana L S; Oliveira, Jose T A; de Souza, Gustavo A; Vasconcelos, Ilka M

2016-12-02

Viruses are important plant pathogens that threaten diverse crops worldwide. Diseases caused by Cowpea severe mosaic virus (CPSMV) have drawn attention because of the serious damages they cause to economically important crops including cowpea. This work was undertaken to quantify and identify the responsive proteins of a susceptible cowpea genotype infected with CPSMV, in comparison with mock-inoculated controls, using label-free quantitative proteomics and databanks, aiming at providing insights on the molecular basis of this compatible interaction. Cowpea leaves were mock- or CPSMV-inoculated and 2 and 6 days later proteins were extracted and analyzed. More than 3000 proteins were identified (data available via ProteomeXchange, identifier PXD005025) and 75 and 55 of them differentially accumulated in response to CPSMV, at 2 and 6 DAI, respectively. At 2 DAI, 76% of the proteins decreased in amount and 24% increased. However, at 6 DAI, 100% of the identified proteins increased. Thus, CPSMV transiently suppresses the synthesis of proteins involved particularly in the redox homeostasis, protein synthesis, defense, stress, RNA/DNA metabolism, signaling, and other functions, allowing viral invasion and spread in cowpea tissues.

Alleviating acid soil stress in cowpea with a local population of ...

African Journals Online (AJOL)

Alleviating acid soil stress in cowpea with a local population of arbuscular ... Roots of the cowpea lines were all heavily colonized by the fungi and their leaf P was ... Total dry weight of inoculated cowpea was not affected by soil acidity while it ...

ECONOMIC ANALYSIS OF COWPEA PRODUCTION IN NIGERIA

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Abba M. Wakili

2013-01-01

Full Text Available This study employs a stochastic frontier production function analysis to examine the productivity and technical efficiency of cowpea production in Adamawa State, Nigeria and also to identify the factors affecting the technical inefficiency using farm level survey data collected from 150 cowpea farmers selected using multi stage sampling technique. Findings from the analysis show that cowpea farmers operated on a very small scale and are profitable. The productivity analysis shows that agro chemicals, fertilizer, farm size and labor were all positively and significantly related to the technical efficiency. The return to scale (RTS of 0.9904 shows that cowpea production was in the rational stage of the production surface. The technical efficiency varies from 0.1094 to 0.9568 with a mean technical efficiency of 0.6649, indicating that farmers were operating below the efficiency frontier. Thus, in the short run, there is a scope to increase output by 34%. The inefficiency model revealed that education of the farmers; extension visits and access to credit are the main factors that affect technical efficiency of the farmers.

Studies in Sri Lanka on cowpea: N2 fixation, growth, yield, and effects on cereals

International Nuclear Information System (INIS)

Senaratne, R.; Dayatilake, G.A.; Subasinghe, S.

1998-01-01

The impact of seed inoculation and N-fertilization on nodulation, plant dry-matter production, and seed yield was studied through a series of field experiments with cultivars of cowpea. In some instances there were positive growth responses to applied N, indicating the potential to improve N 2 fixation and yields by combining compatible genotypes and bradyrhizobial strains. Beneficial residual effects on growth of subsequent maize could not be related to N 2 fixation by the preceding cowpea. Although there was no evidence of direct transfer of N from cowpea to intercropped maize, there was greater efficiency of use of N for total crop production during intercropping

European cowpea landraces for a more sustainable agriculture system and novel foods.

Science.gov (United States)

Carvalho, Márcia; Bebeli, Penelope J; Pereira, Graça; Castro, Isaura; Egea-Gilabert, Catalina; Matos, Manuela; Lazaridi, Efstathia; Duarte, Isabel; Lino-Neto, Teresa; Ntatsi, Georgia; Rodrigues, Miguel; Savvas, Dimitrios; Rosa, Eduardo; Carnide, Valdemar

2017-10-01

Genetic diversity is fundamental to breeding programs and consequently has an important role in obtaining new varieties. To properly use the genetic diversity present in germplasm collections, a good knowledge of the agro-morphological traits of each accession is needed. The aim of this study was to explore the production capacity of 24 cowpea landraces from southern Europe, through phenotypic characterization and evaluation in three different locations in Greece and Portugal. Most qualitative parameters tested showed a high stability among the three locations. A wide difference was observed among the three locations with respect to number of days to flowering, ranging from 55 to 99 days. Quantitative traits showed a higher genotype × environment than genetic variance component. In general, an inverse relationship between σ 2 ge /σ 2 g ratio (where σ 2 ge is genotype × genotype interaction and σ 2 g is genotype impact) and heritability value was observed. Principal component analysis was able to group accessions based on their origin. The first two principal components explained 97.52% of variation, being the number of seeds per plant, plant height and seed protein content, the traits which contributed most to variability. The results show that sufficient variation exists in different traits within landraces in the studied cowpea germplasm to pursue a breeding program. However, the quantitative traits showed a higher genotype × environment component. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Drought increases cowpea (Vigna unguiculata [L.] Walp.) susceptibility to cowpea severe mosaic virus (CPSMV) at early stage of infection.

Science.gov (United States)

Silva, Rodolpho G G; Vasconcelos, Ilka M; Martins, Thiago F; Varela, Anna L N; Souza, Pedro F N; Lobo, Ana K M; Silva, Fredy D A; Silveira, Joaquim A G; Oliveira, Jose T A

2016-12-01

The physiological and biochemical responses of a drought tolerant, virus-susceptible cowpea genotype exposed to drought stress (D), infected by Cowpea severe mosaic virus (CPSMV) (V), and to these two combined stresses (DV), at 2 and 6 days post viral inoculation (DPI), were evaluated. Gas exchange parameters (net photosynthesis, transpiration rate, stomatal conductance, and internal CO 2 partial pressure) were reduced in D and DV at 2 and 6 DPI compared to control plants (C). Photosynthesis was reduced by stomatal and biochemical limitations. Water use efficiency increased at 2 DPI in D, DV, and V, but at 6 DPI only in D and DV compared to C. Photochemical parameters (effective quantum efficiency of photosystem II and electron transport rate) decreased in D and DV compared to C, especially at 6 DPI. The potential quantum efficiency of photosystem II did not change, indicating reversible photoinhibition of photosystem II. In DV, catalase decreased at 2 and 6 DPI, ascorbate peroxidase increased at 2 DPI, but decreased at 6 DPI. Hydrogen peroxide increased at 2 and 6 DPI. Peroxidase increased at 6 DPI and chitinase at 2 and 6 DPI. β-1,3-glucanase decreased in DV at 6 DPI compared to V. Drought increased cowpea susceptibility to CPSMV at 2 DPI, as verified by RT-PCR. However, at 6 DPI, the cowpea plants overcome this effect. Likewise, CPSMV increased the negative effects of drought at 2 DPI, but not at 6 DPI. It was concluded that the responses to combined stresses are not additive and cannot be extrapolated from the study of individual stresses. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Importance and correlations of characters for cowpea diversity in traditional varieties

Directory of Open Access Journals (Sweden)

Márcia Silva de Mendonça

Full Text Available ABSTRACT Cowpea is a legume with ample plasticity, versatility and nutritional potential. It is a species widely used as a source of income and subsistence for small farmers in several Brazilian states, among them Acre. Due to the different varieties found in the State, it is the target of studies aiming at its genetic improvement. Thus, as one of the first stages of its improvement, it was aimed to determine the importance and correlations of characters for diversity and selection in traditional varieties of cowpea. The experiment was carried in completely randomized design, with plots consisting of four vase with capacity to 15.7 L, with one plant each and two replicates. The characteristics evaluated were: days for emergence, flowering (days, plant vigor (note, number of main stem nodes, apical leaflet length (mm, apical leaflet width (mm, length of pod (cm and width of the pod (cm. The correlation coefficients (phenotypic, genotypic and environmental were obtained, and the principal components analysis and the importance of the characters by the method proposed by Singh were carried out. The Singh method and principal components analysis were partially concordant in the distinction of the evaluated characters. The days for emergence, width of the apical leaflet, flowering and length of the apical leaflet were the main determinants for quantification of the genotypes and those that contributed the most to the variability of cowpea. The least discriminant characteristic by principal component analysis and recommended for discarding was plant vigor.

participatory selection of mungbean genotypes in uganda abstract

African Journals Online (AJOL)

ACSS

2017-05-29

May 29, 2017 ... that there were no significant differences in genotype choices based on gender ... However, there were significant genotype preference differences between eastern and northern regions (χ2 = ..... for southern Ethiopia. ... of improved cowpea cultivars in the Guinea and Sudan savanna zones of north east.

Physical, proximate, functional and pasting properties of flour produced from gamma irradiated cowpea (Vigna unguiculata, L. Walp)

International Nuclear Information System (INIS)

Darfour, B.; Wilson, D.D.; Ofosu, D.O.; Ocloo, F.C.K.

2012-01-01

Cowpeas are leguminous seeds widely produced and consumed in most developing countries of sub Saharan Africa. The aim of this study was to determine the physical, proximate, functional and pasting properties of flour obtained from gamma irradiated cowpea. Four cowpea cultivars were irradiated with gamma radiation at dose levels of 0.25, 0.5, 0.75, 1.0 and 1.5 kGy with the unirradiated cultivars serving as controls. The samples were hammer milled, sieved and stored at 4 °C for analysis. Physical, proximate, functional, pasting properties were determined using appropriate methods. In general, the irradiation dose applied to cowpea for insect control did not significantly affect the physical and proximate properties of the flour. However, significant increase (p<0.05) was achieved in paste bulk density, water and oil absorption capacities, foam capacities and least gelation concentrations of flour in general, which may be attributed to the irradiation. The radiation reduced the swelling power and water solubility index significantly. The peak temperature, peak viscosity and setback viscosity of the pastes were significantly (p<0.05) reduced while breakdown viscosity was significantly (p<0.05) increased by the radiation. It was established that the doses used on cowpea affected both the functional and pasting properties of the flour. - Highlights: ► We investigated the effects of gamma irradiation of cowpea on quality characteristics of its resultant flour. ► Flour was prepared from four cowpea cultivars irradiated at 0, 0.25, 0.5, 0.75, 1.0 and 1.5 kGy. ► Proximate and physical properties of flour from irradiated cowpea were generally not affected by the radiation doses used. ► Functional properties of flour samples were affected by gamma irradiation of cowpea. ► Pasting parameters studied were also affected by the radiation at various radiation doses.

Advantage of Sesame and Cowpea Intercrops in Different Fertilizer Application Systems

Directory of Open Access Journals (Sweden)

Jasem Aminifar

2017-04-01

Full Text Available To investigate the effects of different fertilizer applications and sesame/cowpea intercropping systems on soil fertility, a split plot experiment based on randomized complete block design was conducted in Fasa, Fars province, during 2014. The main plots were five fertilizer levels consisted of: using chemical fertilizers nitrogen+phosphorous (F1, organic fertilizers (F2, biofertilizers (F3, 50% chemical fertilizer + 50% organic fertilizer (F4 and 50% chemical fertilizer + 50% biofertilizer (F5, and sub plots consisted of: sole cropping of sesame (M1, sole cropping of cowpea (M2, 50:50 sesame-cowpea intercropping (M3, 75:25 sesame-cowpea intercropping (M4 and 25:75 sesame-cowpea intercropping (M5. The results showed that soil fertility and cropping systems affected the yield and yield components of sesame and cowpea significantly. The highest yield of sesame (1292.6 kg.ha-1, and cowpea (3772.4 kg.ha-1 were obtained from their sole croppings. Among the applications of fertilizer, the highest yield of sesame (950.49 kg.ha-1 and cowpea (2582.50 kg.ha-1 belonged to bioorganic and biofertilizer treatments, respectively. In spite of these results, the highest land equivalent ratio (LER belonged to F4 (1.24 and M3 (1.03 treatments. In general, according to the results, it seems that 50:50 sesame-cowpea intercropping (M3 and application of 30 kg.ha-1 N + 50 kg.ha-1 P + 150 kg.ha-1 bio-organic fertilizer (F4, may reduce application of chemical fertilizers and be beneficial to sesame-cowpea intercropping system.

Association analysis of salt tolerance in cowpea (Vigna unguiculata (L.) Walp) at germination and seedling stages

Science.gov (United States)

Cowpea is one of the most important cultivated legumes in Africa. The worldwide annual production in cowpea dry seed is 5.4 million metric tons. However, cowpea is unfavorably affected by salinity stress at germination and seedling stages, which is exacerbated by the effects of climate change. The l...

Zinc fertilization in cowpea cultivars

Directory of Open Access Journals (Sweden)

Francisco de Brito Melo

Full Text Available ABSTRACT Zinc (Zn is an essential micronutrient for plants, due to its role as a functional, structural, or regulatory cofactor in a large number of enzymes. The element is necessary for the synthesis of tryptophan, which is a precursor of indoleacetic acid. The aim of this study was to evaluate the behavior of two cowpea cultivars fertilized with four doses of Zn (0.0, 2.0, 4.0, and 6.0 kg of Zn ha-1 regarding dry grain yield (PGS, in addition to quantifying leaf and grain Zn content and grain crude protein. The experiment was conducted in the town of Brejo, in the state of Maranhão, Brazil. A 4 x 2 factorial scheme was used with four replications. Response functions were adjusted by calculating the Zn doses which provided a maximum technical efficiency for each genotype. The tested cultivars of cowpea showed no great difference regarding Zn demand applied to the soil, ranging from 3.2 to 3.4 kg of Zn ha-1 for BRS Tumucumaque and BRS Guariba, respectively. Concerning Zn use efficiency, BRS Guariba was more responsive than was BRS Tumucumaque, i.e. the same dose of Zn produced 70 kg grain and 2.1 kg crude protein per hectare.

Effects of irradiation on physical and sensory characteristics of cowpea seed cultivars (Vigna unguiculata L. Walp)

International Nuclear Information System (INIS)

Ocloo, F.C.K.; Darfour, B.; Ofosu, D.O.; Wilson, D.D.

2012-01-01

Cowpeas (Vigna unguiculata L. Walp) are leguminous seeds widely produced and consumed in most developing countries of sub-Saharan Africa where they are a good source of affordable proteins, minerals and vitamins to the mainly carbohydrate-based diet of sub-Saharan Africa. At storage cowpea may be attacked by insects that cause severe damage to the seeds. The objective of this study was to investigate the effects of gamma irradiation on some physical and sensory characteristics of cowpea seed cultivars. Four cowpea cultivars were irradiated with gamma radiation at dose levels of 0.25, 0.50, 0.75, 1.0 and 1.5 kGy. Moisture content, thousand grain weight and bulk densities were determined as well as the amount of water absorbed during soaking and some sensory characteristics were equally determined. All the physical parameters studied were not significantly (p>0.05) affected by the radiation. There was no significant (p>0.05) effect of the radiation on the sensory attributes like flavour, taste, texture, softness and colour of the cowpea seeds. Similarly, the radiation did not affect significantly (p>0.05) the acceptability of the treated cowpea cultivars. - Highlights: → We investigated the effects of gamma irradiation on some physical and sensory characteristics of cowpea seed cultivars. → Four cowpea cultivars were irradiated at dose levels of 0.25, 0.50, 0.75, 1.0 and 1.5 kGy. → Physical parameters were not significantly (p>0.05) affected by the radiation. → Sensory attributes considered were not significantly influenced by the radiation doses used.

Effects of irradiation on physical and sensory characteristics of cowpea seed cultivars (Vigna unguiculata L. Walp)

Energy Technology Data Exchange (ETDEWEB)

Ocloo, F.C.K., E-mail: fidelis_ocloo@yahoo.com [Radiation Technology Centre, Biotechnology and Nuclear Agriculture Research Institute, Ghana Atomic Energy Commission. P.O. Box LG 80, Legon (Ghana); Darfour, B.; Ofosu, D.O. [Radiation Technology Centre, Biotechnology and Nuclear Agriculture Research Institute, Ghana Atomic Energy Commission. P.O. Box LG 80, Legon (Ghana); Wilson, D.D. [Department of Zoology, University of Ghana, Legon (Ghana)

2012-01-15

Cowpeas (Vigna unguiculata L. Walp) are leguminous seeds widely produced and consumed in most developing countries of sub-Saharan Africa where they are a good source of affordable proteins, minerals and vitamins to the mainly carbohydrate-based diet of sub-Saharan Africa. At storage cowpea may be attacked by insects that cause severe damage to the seeds. The objective of this study was to investigate the effects of gamma irradiation on some physical and sensory characteristics of cowpea seed cultivars. Four cowpea cultivars were irradiated with gamma radiation at dose levels of 0.25, 0.50, 0.75, 1.0 and 1.5 kGy. Moisture content, thousand grain weight and bulk densities were determined as well as the amount of water absorbed during soaking and some sensory characteristics were equally determined. All the physical parameters studied were not significantly (p>0.05) affected by the radiation. There was no significant (p>0.05) effect of the radiation on the sensory attributes like flavour, taste, texture, softness and colour of the cowpea seeds. Similarly, the radiation did not affect significantly (p>0.05) the acceptability of the treated cowpea cultivars. - Highlights: > We investigated the effects of gamma irradiation on some physical and sensory characteristics of cowpea seed cultivars. > Four cowpea cultivars were irradiated at dose levels of 0.25, 0.50, 0.75, 1.0 and 1.5 kGy. > Physical parameters were not significantly (p>0.05) affected by the radiation. > Sensory attributes considered were not significantly influenced by the radiation doses used.

RNA-dependent RNA polymerases from cowpea mosaic virus-infected cowpea leaves

NARCIS (Netherlands)

Dorssers, L.

1983-01-01

The aim of the research described in this thesis was the purification and identification of the RNA-dependent RNA polymerase engaged in replicating viral RNA in cowpea mosaic virus (CPMV)- infected cowpea leaves.

Previously, an RNA-dependent RNA polymerase produced upon infection of

Effect of Spatial Arrangement on Growth and Yield of Cowpea in a Cowpea-maize Intercrop

OpenAIRE

Ocaya, CP.; Adipala, E.; Osiru, DSO.

2001-01-01

Cowpea growth and yield performance when intercropped with maize was studied for 3 consecutive seasons under three spatial arrangements, i. e., maize planted at 90 x 30, 100 x 27, and 120 x 22.5 cm, with 2 rows of cowpea between the maize rows. Growth and yield of cowpea was improved significantly by widening maize intra-row distances as compared to the 90 x 30 cm spacing. Hence, intercropped cowpea needs to be sown where maize rows are wide apart, but the maize rows should not be too wide as...

Inheritance of carbon isotope discrimination and water-use efficiency in cowpea

International Nuclear Information System (INIS)

Ismail, A.M.; Hall, A.E.

1993-01-01

Theory has been developed predicting an association between water-use efficiency (WUE = total biomass/transpiration) and leaf discrimination against 13C carbon isotope discrimination which could be used to indirectly select for WUE in C3 plants. Previous studies indicated variation in WUE and carbon isotope discrimination among genotypes of cowpea [Vigna unguiculata (L.) Walp.] and due to drought. Moreover, a highly significant negative correlation between WUE and carbon isotope discrimination was observed for both genotypic and drought effects, as expected based on theory. Present studies were conducted to investigate whether the inheritance of WUE and carbon isotope discrimination is nuclear or maternal, and whether any dominance is present. Contrasting cowpea accessions and hybrids were grown over 2 yr in two outdoor pot experiments, subjected to wet or dry treatments, and under full irrigation in natural soil conditions in 1 yr. Highly significant differences in WUE were observed among cowpea parents and hybrids, and due to drought, which were strongly and negatively correlated with carbon isotope discrimination as expected based on theory. Data from reciprocal crosses indicated that both WUE and carbon isotope discrimination are controlled by nuclear genes. High WUE and low carbon isotope discrimination exhibited partial dominance under pot conditions. In contrast, high carbon isotope discrimination was partially dominant for plants grown under natural soil conditions but in a similar aerial environment as in the pot studies. We speculate that differences in rooting conditions were responsible for the differences in extent of dominance for carbon isotope discrimination of plants growing under pot conditions compared with natural soil conditions in a similar field aerial environment

Effect of Spatial Arrangement on Growth and Yield of Cowpea in a Cowpea-maize Intercrop

Directory of Open Access Journals (Sweden)

Ocaya, CP.

2001-01-01

Full Text Available Cowpea growth and yield performance when intercropped with maize was studied for 3 consecutive seasons under three spatial arrangements, i. e., maize planted at 90 x 30, 100 x 27, and 120 x 22.5 cm, with 2 rows of cowpea between the maize rows. Growth and yield of cowpea was improved significantly by widening maize intra-row distances as compared to the 90 x 30 cm spacing. Hence, intercropped cowpea needs to be sown where maize rows are wide apart, but the maize rows should not be too wide as this would lower the grain yield of maize.

Avaliação de genótipos de caupi sob salinidade Assessment of cowpea genotypes under salinity

Directory of Open Access Journals (Sweden)

José P. Dantas

2002-12-01

Full Text Available Foram conduzidos ensaios em abrigo telado de vegetação com cobertura de telha de fibra de vidro com o objetivo de se avaliar a tolerância de 50 genótipos de caupi sob salinidade. Os tratamentos de salinidade aplicados no solo, em termos de condutividade elétrica do extrato de saturação (CE, foram: CE1 - 0,3, CE2 - 3,0, CE3 - 6,0, CE4 - 9,0 e CE5 - 12,0 dS m-1. Os genótipos foram classificados para tolerância à salinidade com base na redução percentual do peso de matéria seca da parte aérea. No tratamento CE2, 36 genótipos foram tolerantes (T, 12 moderadamente tolerantes (MT e 2 moderadamente sensíveis (MS; no tratamento CE3, 3 foram T, 14 MT, 30 MS e 3 sensíveis (S; no tratamento CE4, um foi MS e 49 S e, no tratamento CE5, todos foram S. O teor de proteína nos grãos foi influenciado pela salinidade e variou de genótipo para genótipo.To assess the tolerance of 50 cowpea genotypes under salinity, experiments were conducted in greenhouse covered with fiberglass sheets. The salinity treatments applied in terms of electrical conductivity of saturation extract of soil (EC were EC1 - 0.3; EC2 - 3.0; EC3 - 6.0; EC4 - 9.0 and EC5 - 12.0 dS m-1. The genotypes were classified for the salinity tolerance on the basis of the reduction in dry weight (% of shoot. Under EC2, 36 genotypes were tolerant (T, 12 moderately tolerant (MT and 2 moderately susceptible (MS; under EC3, 3 were T, 14 MT, 30 MS and 3 susceptible (S; under EC4, one was MS and 49 S and under EC5, all were S. The protein content of seed was influenced by salinity and varied with the genotype.

Genomic regions, cellular components and gene regulatory basis underlying pod length variations in cowpea (V. unguiculata L. Walp).

Science.gov (United States)

Xu, Pei; Wu, Xinyi; Muñoz-Amatriaín, María; Wang, Baogen; Wu, Xiaohua; Hu, Yaowen; Huynh, Bao-Lam; Close, Timothy J; Roberts, Philip A; Zhou, Wen; Lu, Zhongfu; Li, Guojing

2017-05-01

Cowpea (V. unguiculata L. Walp) is a climate resilient legume crop important for food security. Cultivated cowpea (V. unguiculata L) generally comprises the bushy, short-podded grain cowpea dominant in Africa and the climbing, long-podded vegetable cowpea popular in Asia. How selection has contributed to the diversification of the two types of cowpea remains largely unknown. In the current study, a novel genotyping assay for over 50 000 SNPs was employed to delineate genomic regions governing pod length. Major, minor and epistatic QTLs were identified through QTL mapping. Seventy-two SNPs associated with pod length were detected by genome-wide association studies (GWAS). Population stratification analysis revealed subdivision among a cowpea germplasm collection consisting of 299 accessions, which is consistent with pod length groups. Genomic scan for selective signals suggested that domestication of vegetable cowpea was accompanied by selection of multiple traits including pod length, while the further improvement process was featured by selection of pod length primarily. Pod growth kinetics assay demonstrated that more durable cell proliferation rather than cell elongation or enlargement was the main reason for longer pods. Transcriptomic analysis suggested the involvement of sugar, gibberellin and nutritional signalling in regulation of pod length. This study establishes the basis for map-based cloning of pod length genes in cowpea and for marker-assisted selection of this trait in breeding programmes. © 2016 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

Effects of irradiation on physical and sensory characteristics of cowpea seed cultivars ( Vigna unguiculata L. Walp)

Science.gov (United States)

Ocloo, F. C. K.; Darfour, B.; Ofosu, D. O.; Wilson, D. D.

2012-01-01

Cowpeas ( Vigna unguiculata L. Walp) are leguminous seeds widely produced and consumed in most developing countries of sub-Saharan Africa where they are a good source of affordable proteins, minerals and vitamins to the mainly carbohydrate-based diet of sub-Saharan Africa. At storage cowpea may be attacked by insects that cause severe damage to the seeds. The objective of this study was to investigate the effects of gamma irradiation on some physical and sensory characteristics of cowpea seed cultivars. Four cowpea cultivars were irradiated with gamma radiation at dose levels of 0.25, 0.50, 0.75, 1.0 and 1.5 kGy. Moisture content, thousand grain weight and bulk densities were determined as well as the amount of water absorbed during soaking and some sensory characteristics were equally determined. All the physical parameters studied were not significantly ( p>0.05) affected by the radiation. There was no significant ( p>0.05) effect of the radiation on the sensory attributes like flavour, taste, texture, softness and colour of the cowpea seeds. Similarly, the radiation did not affect significantly ( p>0.05) the acceptability of the treated cowpea cultivars.

EFFECTS OF COWPEA FORTIFICATION, DEHYDRATION METHOD ...

African Journals Online (AJOL)

Fortification of cereal-based traditional foods with legume protein can improve their nutritional value. It is, however, important to find out the extent to which the addition of cowpea affects the desirable quality characteristics of traditional weaning foods prepared from fermented maize and also to assess the effect of ...

Diversity and Symbiotic Characteristics of Cowpea Bradyrhizobium Strains in Ghanaian Soils

International Nuclear Information System (INIS)

Fening, Joseph Opoku

1999-08-01

. Analysis of the 16S rRNA gene of the isolates by PCR-RFLP identified 20 different composite genotypes. Diversity among the genomic species identified was very high, reaching 80% diversity. The various methods used indicated large diversity among the isolates, but the groupings of the isolates by the various methods were inconsistent, due to the different levels of resolution by the various methods. Diversity of the isolates in symbiotic effectiveness showed that some of the isolates had high nitrogen fixing capabilities that were comparable to plants fertilized with inorganic fertilizer nitrogen. Some of the isolates even showed superiority in symbiotic effectiveness relative to the standard strain TAL 169, suggesting that the native isolates may be useful strains for cowpea inoculation. The Gus A marker gene technique was used to assess the competitive abilities of the effective and ineffective isolates. Competition between the isolates was examined at different population ratios. The results obtained indicated that competitive ability was not directly related to effectiveness of strains. Inoculation of cowpea with indigenous bradyrhizobia isolates increased the number of nodules, shoot dry weight and total nitrogen of plants. The method of inoculation was observed to influence these parameters The results indicated that response of cowpea to inoculation in the presence of native rhizobia in some soils is possible. (au)

A major QTL corresponding to the Rk locus for resistance to root-knot nematodes in cowpea (Vigna unguiculata L. Walp.).

Science.gov (United States)

Huynh, Bao-Lam; Matthews, William C; Ehlers, Jeffrey D; Lucas, Mitchell R; Santos, Jansen R P; Ndeve, Arsenio; Close, Timothy J; Roberts, Philip A

2016-01-01

Genome resolution of a major QTL associated with the Rk locus in cowpea for resistance to root-knot nematodes has significance for plant breeding programs and R gene characterization. Cowpea (Vigna unguiculata L. Walp.) is a susceptible host of root-knot nematodes (Meloidogyne spp.) (RKN), major plant-parasitic pests in global agriculture. To date, breeding for host resistance in cowpea has relied on phenotypic selection which requires time-consuming and expensive controlled infection assays. To facilitate marker-based selection, we aimed to identify and map quantitative trait loci (QTL) conferring the resistance trait. One recombinant inbred line (RIL) and two F2:3 populations, each derived from a cross between a susceptible and a resistant parent, were genotyped with genome-wide single nucleotide polymorphism (SNP) markers. The populations were screened in the field for root-galling symptoms and/or under growth-chamber conditions for nematode reproduction levels using M. incognita and M. javanica biotypes. One major QTL was mapped consistently on linkage group VuLG11 of each population. By genotyping additional cowpea lines and near-isogenic lines derived from conventional backcrossing, we confirmed that the detected QTL co-localized with the genome region associated with the Rk locus for RKN resistance that has been used in conventional breeding for many decades. This chromosomal location defined with flanking markers will be a valuable target in marker-assisted breeding and for positional cloning of genes controlling RKN resistance.

Quality characteristics of gamma irradiated cowpea (vigna unguiculata, L. walp) cultivars in Ghana and their resultant flours

International Nuclear Information System (INIS)

Darfour, B.

2010-01-01

Cowpeas are leguminous seeds widely produced and consumed in most developing countries of sub Saharan Africa. During storage, cowpeas may be attacked by a number of biological agents (microorganisms, rodents, and insects) which results in losses in the quality and quantity of the stored seeds. These losses can be minimized by irradiating the stored cowpea against microorganisms and insects attacks primarily Callosobruchus maculatus. The aim of this study was to evaluate quality characteristics of gamma irradiated cowpea cultivars and their resultant flours. Four cowpea cultivars were irradiated with gamma radiation at dose levels of 0.25 kGy, 0.5 kGy, 0.75 kGy, 1.0 kGy and 1.5 kGy. The unirradiated cultivars were used as controls. A portion of the samples were hammer milled, passed through sieve of 250μm and stored at 4 o C for analysis. Physicochemical, functional, pasting and sensory properties were determined using standards and/or appropriate methods. Moisture sorption isotherms of the cowpea samples were also determined. Radiosensitivity and storage studies on Callosobruchus maculatus were also done for one month. In general, significant effect (p 0.05) affected by the irradiation. All the physical parameters studied were not significantly (p > 0.05) affected by the radiation. Generally, significant increase (p o C. There was no significant (p > 0.05) effect of the radiation on the sensory attributes like flavour, taste, texture, softness and colour of the cowpea seeds. Similarly, the radiation did not affect significantly (p > 0.05) the acceptability of the treated cowpea cultivars. Irradiating at even a dose of 0.25 kGy killed the insects on average within eight days. There was significant difference (p < 0.05) in the percent mortality between the irradiated and the non-irradiated weevils. The percent mortality increased with increase in the radiation dose. It was established that at the lower doses studied although the radiation effect did not follow any

Physical, proximate, functional and pasting properties of flour produced from gamma irradiated cowpea (Vigna unguiculata, L. Walp)

Science.gov (United States)

Darfour, B.; Wilson, D. D.; Ofosu, D. O.; Ocloo, F. C. K.

2012-04-01

Cowpeas are leguminous seeds widely produced and consumed in most developing countries of sub Saharan Africa. The aim of this study was to determine the physical, proximate, functional and pasting properties of flour obtained from gamma irradiated cowpea. Four cowpea cultivars were irradiated with gamma radiation at dose levels of 0.25, 0.5, 0.75, 1.0 and 1.5 kGy with the unirradiated cultivars serving as controls. The samples were hammer milled, sieved and stored at 4 °C for analysis. Physical, proximate, functional, pasting properties were determined using appropriate methods. In general, the irradiation dose applied to cowpea for insect control did not significantly affect the physical and proximate properties of the flour. However, significant increase (pcowpea affected both the functional and pasting properties of the flour.

Complete genome sequences of cowpea polerovirus 1 and cowpea polerovirus 2 infecting cowpea plants in Burkina Faso.

Science.gov (United States)

Palanga, Essowè; Martin, Darren P; Galzi, Serge; Zabré, Jean; Bouda, Zakaria; Neya, James Bouma; Sawadogo, Mahamadou; Traore, Oumar; Peterschmitt, Michel; Roumagnac, Philippe; Filloux, Denis

2017-07-01

The full-length genome sequences of two novel poleroviruses found infecting cowpea plants, cowpea polerovirus 1 (CPPV1) and cowpea polerovirus 2 (CPPV2), were determined using overlapping RT-PCR and RACE-PCR. Whereas the 5845-nt CPPV1 genome was most similar to chickpea chlorotic stunt virus (73% identity), the 5945-nt CPPV2 genome was most similar to phasey bean mild yellow virus (86% identity). The CPPV1 and CPPV2 genomes both have a typical polerovirus genome organization. Phylogenetic analysis of the inferred P1-P2 and P3 amino acid sequences confirmed that CPPV1 and CPPV2 are indeed poleroviruses. Four apparently unique recombination events were detected within a dataset of 12 full polerovirus genome sequences, including two events in the CPPV2 genome. Based on the current species demarcation criteria for the family Luteoviridae, we tentatively propose that CPPV1 and CPPV2 should be considered members of novel polerovirus species.

A novel method for conserving cowpea germplasm and breeding stocks using solar disinfestation

Energy Technology Data Exchange (ETDEWEB)

Ntoukam, G.; Kitch, L.W.; Shade, R.E.; Murdock, L.L. [Purdue Univ., Entomology Dept., Lafayette, IN (United States)

1997-10-01

Experiments conducted in Maroua, Cameroon, demonstrated that a large 50-kg-capacity solar heater can be used to successfully eradicate infestations of Callosobruchus maculatus from cowpea seeds kept in small, transparent Minigrip zip lock plastic bags. Temperatures produced inside the heater were sufficient to kill all developing insects living within infested cowpea seeds. Small, transparent ziplock plastic bags are useful seed storage containers for short-term cowpea germplasm collections and are easily inspected during storage following solar disinfestation. Published reports indicate that temperatures of up to 85{sup o}C do not adversely affect seed germination, germination rates, or seeding viability. These temperature and biological experiments provide evidence that the solar heater technique can serve as an effective and practical means to improve the short-term storage of cowpea seeds in developing country national agricultural research programs. (author)

Effect of cowpea aphid-borne mosaic virus on penetration and reproduction of meloidogyne incognita in cowpea

OpenAIRE

Adekunle O.K.; Owa T.E.

2008-01-01

greenhouse studies were conducted to investigate the effects of cowpea aphid-borne mosaic virus on penetration and reproduction of Meloidogyne incognita in cowpea and the influence of these pathogens on the yield of cowpea. The interaction of both pathogens resulted in higher population density of the nematode at harvest and correspondingly reduced grain yield in comparison to inoculation of either pathogen alone or un-inoculated control. An almost equal number of nematode juveniles penetrate...

NaCl Effects on In Vitro Germination and Growth of Some Senegalese Cowpea (Vigna unguiculata (L.) Walp.) Cultivars

Science.gov (United States)

Thiam, Mahamadou; Ourèye SY, Mame

2013-01-01

Cowpea (Vigna unguiculata (L.) Walp.) is one of the most important grain legumes in sub-Saharian regions. It contributes to man food security by providing a protein-rich diet. However, its production is limited by abiotic stresses such as salinity. This study aims to evaluate the salt tolerance of 15 cowpea cultivars, at germination stage. The seed germination process consisted of sowing them in agarified water (8 g·L−1) supplemented with 6 different concentrations of NaCl (0, 10, 50, 100, 150, and 200 mM). Results highlighted that high salt concentrations drastically reduced germination and significantly delayed the process for all varieties. A cowpea varietal effect towards the salt tolerance was noticed. Genotypes Diongoma, 58-78, and 58-191 were more salt-tolerant cultivars while Mougne and Yacine were more salt-sensitive ones as confirmed in the three groups of the dendrogram. NaCl effects on the early vegetative growth of seedlings were assessed with a tolerant (58-191) and a susceptible (Yacine) cultivar. Morphological (length and dry biomass) and physiological (chlorophyll and proline contents) parameter measurements revealed a negative effect of high (NaCl). However, 58-191 was much more salt tolerant, and the chlorophyll and proline contents were higher than those of Yacine genotype at increasing salt concentrations. PMID:25937976

Relative planting times on the production components in sesame/cowpea bean intercropping in organic system

Directory of Open Access Journals (Sweden)

Afrânio César de Araújo

2013-12-01

Full Text Available Aiming at better land use, small farmers usually plant sesame and cowpea bean intercropped with other crops. The aim of this work was to analyze and quantify the influence of four relative planting times of the cowpea bean in intercropping with sesame from the standpoint of their production components, plant productivity and the index of land equivalent ratio (LER. The field experiment was conducted in a randomized blocks with four treatments and four replicates. The treatments were the sesame and the cowpea bean in intercropping with the cowpea bean planted at the same time, 7, 14 and 21days after than the sesame. A greater part of the production components of both the sesame as well the cowpea bean was affected by the intercropping and significant differences were noted among the treatments in a larger part of the parameters. As the planting of the cowpea bean became more distant from that of the sesame, the yield of the Pedaliaceae increased and the yield of the Fabaceae decreased. The results for LER findings on the other hand suggest that in the sesame/cowpea bean intercropping, when the Fabaceae is planted seven days after the sesame, there is better use of the land and a largest possibility to the producer earning a profit.

Association analysis of cowpea mosaic virus (CPMV) resistance in the USDA cowpea germplasm collection

Science.gov (United States)

Cowpea [Vigna unguiculata (L.) Walp.] is an important legume crop, widely grown in Africa, South America, South Asia, Southeast Asia, and the southern United States. Cowpea is consumed as both fresh vegetable and dry grain, and as an animal feed and fodder, and it is a major dietary protein source t...

Preservation of Cowpea (Vigna unguiculata (L.) Walp) Grains against Cowpea Bruchids (Callosobruchus maculatus) Using Neem and Moringa Seed Oils

OpenAIRE

Ilesanmi, Joana O.; Gungula, Daniel T.

2010-01-01

This study was conducted to determine the effects of neem (Azadirachta indica A. Juss) and moringa (Moringa oleifera) seed oils on the storability of cowpea grain. Cowpea samples were treated with various concentrations (0.5, 1.0, and 1.5 mL/200 g cowpea) of pure neem and moringa oils and their mixtures in ratios of 1:1, 1:2, and 1:3. The treated cowpea samples were stored for 180 days. Data were collected every 30 days on number of eggs laid, total weevil population, and percentage of uninfe...

H2O2 plays an important role in the lifestyle of Colletotrichum gloeosporioides during interaction with cowpea [Vigna unguiculata (L.) Walp].

Science.gov (United States)

Eloy, Ygor R G; Vasconcelos, Ilka M; Barreto, Ana L H; Freire-Filho, Francisco R; Oliveira, Jose T A

2015-08-01

Plant-fungus interactions usually generate H(2)O(2) in the infected plant tissue. H(2)O(2) has a direct antimicrobial effect and is involved in the cross-linking of cell walls, signaling, induction of gene expression, hypersensitive cell death and induced systemic acquired resistance. This has raised the hypothesis that H(2)O(2) manipulation by pharmacological compounds could alter the lifestyle of Colletotrichum gloeosporioides during interaction with the BR-3-Tracuateua cowpea genotype. The primary leaves of cowpea were excised, infiltrated with salicylic acid (SA), glucose oxidase + glucose (GO/G), catalase (CAT) or diphenyliodonium chloride (DPI), followed by spore inoculation on the adaxial leaf surface. SA or GO/G-treated plantlets showed increased H(2)O(2) accumulation and lipid peroxidation. The fungus used a subcuticular, intramural necrotrophic strategy, and developed secondary hyphae associated with the quick spread and rapid killing of host cells. However, CAT or DPI-treated leaves exhibited decreased H(2)O(2) concentration and lipid peroxidation and the fungus developed intracellular hemibiotrophic infection with vesicles, in addition to primary and secondary hyphal formation. These results suggest that H(2)O(2) plays an important role in the cowpea (C. gloeosporioides) pathosystem given that it affected fungal lifestyle during interaction. Copyright © 2015 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Genetic variability in cowpea (Vigna unguiculata (L.) Walp.) genotypes

African Journals Online (AJOL)

sive protein in human diets with grains containing about. 23–25% protein ... Keywords: heritability, phenotype, principal component analysis, variance. Introduction .... be due to genotype, environment, and the interaction of genotype and ...

Preferência do pulgão-preto e da cigarrinha-verde em diferentes genótipos de feijão-caupi em Roraima = Preference of the black aphid and green leafhopper in different genotypes of cowpea in Roraima, Brazil

Directory of Open Access Journals (Sweden)

Hugo Falkyner da Silva Bandeira

2015-03-01

Full Text Available A ocorrência de insetos praga está entre os fatores que mais afetam a produtividade do feijão-caupi. Objetivou-se, com este trabalho, avaliar a resistência de nove genótipos de feijão-caupi ao ataque do pulgão-preto, Aphis craccivora Koch, 1854, e da cigarrinha-verde, (Empoasca sp., e a flutuação populacional de A. craccivora sobre a cultura, em condições de campo. Foram selecionados nove genótipos de feijão-caupi (Vigna unguiculata (L. Walp, a saber: BR-17 Gurgueia, BRS Guariba, BRS Cauamé, Pretinho Precoce 1, UFRR Grão Verde, Apiaú, Iracema, Cara-Preta e Sempre Verde. O delineamento experimental foi realizado em blocos casualizados, em esquema de parcela subdividida, com quatro repetições. Cada variedade foi plantada em quatro linhas paralelas, considerando as duas fileiras centrais como área útil. A contagem dos pulgões foi feita diretamente na última folha trifoliolada completamente aberta, enquanto que a das cigarrinhas foi realizada pelo método da batida de plantas em bandeja com água. Nos genótipos BRS Cauamé, BRS Guariba e Pretinho Precoce 1 foram observados os menores índices de infestação por A. craccivora, apresentando, portanto, resistência do tipo não preferência em relação aos demais avaliados. O genótipo Apiaú mostrou-se suscetível a Empoasca sp., e os BR-17 Gurgueia, Cara-Preta, Sempre Verde, UFRR Grão Verde e BRS Cauamé foram os mais resistentes, em função da menor preferência pelas cigarrinhas, registrada, principalmente, aos 28 e 35 dias após a emergência das plantas. = The occurrence of insect pests is among the most important factors affecting cowpea productivity. This study aimed at evaluating the resistance of nine genotypes of cowpea attack in black aphid Aphis craccivora Koch, 1854, and of green leafhopper (Empoasca sp., and the population fluctuation of A. craccivora on culture, under field conditions. Nine cowpea (Vigna unguiculata (L. Walp genotypes were chosen: BR-17

Development of unigene-derived SSR markers in cowpea (Vigna unguiculata) and their transferability to other Vigna species.

Science.gov (United States)

Gupta, S K; Gopalakrishna, T

2010-07-01

Unigene sequences available in public databases provide a cost-effective and valuable source for the development of molecular markers. In this study, the identification and development of unigene-based SSR markers in cowpea (Vigna unguiculata (L.) Walp.) is presented. A total of 1071 SSRs were identified in 15 740 cowpea unigene sequences downloaded from the National Center for Biotechnology Information. The most frequent SSR motifs present in the unigenes were trinucleotides (59.7%), followed by dinucleotides (34.8%), pentanucleotides (4%), and tetranucleotides (1.5%). The copy number varied from 6 to 33 for dinucleotide, 5 to 29 for trinucleotide, 5 to 7 for tetranucleotide, and 4 to 6 for pentanucleotide repeats. Primer pairs were successfully designed for 803 SSR motifs and 102 SSR markers were finally characterized and validated. Putative function was assigned to 64.7% of the unigene SSR markers based on significant homology to reported proteins. About 31.7% of the SSRs were present in coding sequences and 68.3% in untranslated regions of the genes. About 87% of the SSRs located in the coding sequences were trinucleotide repeats. Allelic variation at 32 SSR loci produced 98 alleles in 20 cowpea genotypes. The polymorphic information content for the SSR markers varied from 0.10 to 0.83 with an average of 0.53. These unigene SSR markers showed a high rate of transferability (88%) across other Vigna species, thereby expanding their utility. Alignment of unigene sequences with soybean genomic sequences revealed the presence of introns in amplified products of some of the SSR markers. This study presents the distribution of SSRs in the expressed portion of the cowpea genome and is the first report of the development of functional unigene-based SSR markers in cowpea. These SSR markers would play an important role in molecular mapping, comparative genomics, and marker-assisted selection strategies in cowpea and other Vigna species.

N fixation and transfer in Maize/Cowpea and Sorghum/Cowpea inter cropping systems as determined by N-15 isotope dilution technique

International Nuclear Information System (INIS)

Dayatilake, G.A.; Subasinghe, S.; Senaratne, R.

2000-01-01

N fixation and transfer in maize/cowpea and sorghum/cowpea intercropping systems, as determined by N-15 dilution technique was studied in two field trials conducted at Bata-atha, in the dry zone of Sri Lanka. Two cvs. of cowpea i.e; Bombay and MI-35 were used in maize/cowpea intercropping system, with following combinations of treatments; maize/Bombay, maize/MI-35, Bombay (monocrop), MI-35 (monocrop) and maize (monocrop). A similar set of treatments was used in sorghum/cowpea intercropping system also. The N-15 atom excess, percentage Ndfa, total amount of N fixed, N yield and the total dry matter production were estimated. Maize/cowpea intercropping resulted in an increase in total dry matter production and total N yield compared to monocrop treatment. However the percentage Ndfa and total N fixed showed a decrease compared to monocrop stand. The percentage Ndfa was 60-65 percent monocrop while the same was 45-50 percent in intercropped treatments

Comparative Analysis of the Combined Effects of Different Water and Phosphate Levels on Growth and Biological Nitrogen Fixation of Nine Cowpea Varieties.

Science.gov (United States)

Jemo, Martin; Sulieman, Saad; Bekkaoui, Faouzi; Olomide, Oluwatosin A K; Hashem, Abeer; Abd Allah, Elsayed Fathi; Alqarawi, Abdulaziz A; Tran, Lam-Son Phan

2017-01-01

Water deficit and phosphate (Pi) deficiency adversely affect growth and biological nitrogen fixation (BNF) of legume crops. In this study, we examined the impact of interaction between soil water conditions and available soil-Pi levels on growth, nodule development and BNF potential of nine cowpea varieties grown on dry savanna soils. In our experimental design, soils with different available soil-Pi levels, i.e., low, moderate, and high soil-Pi levels, collected from various farming fields were used to grow nine cowpea varieties under well-watered and water-deficit conditions. Significant and severe water deficit-damaging effects on BNF, nodulation, growth, levels of plant-nitrogen (N) and -phosphorus (P), as well as shoot relative water content and chlorophyll content of cowpea plants were observed. Under well-watered and high available soil-Pi conditions, cowpea varieties IT07K-304-9 and Dan'Ila exhibited significantly higher BNF potential and dry biomass, as well as plant-N and -P contents compared with other tested ones. Significant genotypic variations among the cowpeas were recorded under low available soil-Pi and water-deficit conditions in terms of the BNF potential. Principal component (PC) analysis revealed that varieties IT04K-339-1, IT07K-188-49, IT07K-304-9, and IT04K-405-5 were associated with PC1, which was better explained by performance for nodulation, plant biomass, plant-N, plant-P, and BNF potential under the combined stress of water deficit and Pi deficiency, thereby offering prospects for development of varieties with high growth and BNF traits that are adaptive to such stress conditions in the region. On another hand, variety Dan'Ila was significantly related to PC2 that was highly explained by the plant shoot/root ratio and chlorophyll content, suggesting the existence of physiological and morphological adjustments to cope with water deficit and Pi deficiency for this particular variety. Additionally, increases in soil-Pi availability led

Comparative Analysis of the Combined Effects of Different Water and Phosphate Levels on Growth and Biological Nitrogen Fixation of Nine Cowpea Varieties

Science.gov (United States)

Jemo, Martin; Sulieman, Saad; Bekkaoui, Faouzi; Olomide, Oluwatosin A. K.; Hashem, Abeer; Abd_Allah, Elsayed Fathi; Alqarawi, Abdulaziz A.; Tran, Lam-Son Phan

2017-01-01

Water deficit and phosphate (Pi) deficiency adversely affect growth and biological nitrogen fixation (BNF) of legume crops. In this study, we examined the impact of interaction between soil water conditions and available soil-Pi levels on growth, nodule development and BNF potential of nine cowpea varieties grown on dry savanna soils. In our experimental design, soils with different available soil-Pi levels, i.e., low, moderate, and high soil-Pi levels, collected from various farming fields were used to grow nine cowpea varieties under well-watered and water-deficit conditions. Significant and severe water deficit-damaging effects on BNF, nodulation, growth, levels of plant-nitrogen (N) and -phosphorus (P), as well as shoot relative water content and chlorophyll content of cowpea plants were observed. Under well-watered and high available soil-Pi conditions, cowpea varieties IT07K-304-9 and Dan'Ila exhibited significantly higher BNF potential and dry biomass, as well as plant-N and -P contents compared with other tested ones. Significant genotypic variations among the cowpeas were recorded under low available soil-Pi and water-deficit conditions in terms of the BNF potential. Principal component (PC) analysis revealed that varieties IT04K-339-1, IT07K-188-49, IT07K-304-9, and IT04K-405-5 were associated with PC1, which was better explained by performance for nodulation, plant biomass, plant-N, plant-P, and BNF potential under the combined stress of water deficit and Pi deficiency, thereby offering prospects for development of varieties with high growth and BNF traits that are adaptive to such stress conditions in the region. On another hand, variety Dan'Ila was significantly related to PC2 that was highly explained by the plant shoot/root ratio and chlorophyll content, suggesting the existence of physiological and morphological adjustments to cope with water deficit and Pi deficiency for this particular variety. Additionally, increases in soil-Pi availability led

Comparative Analysis of the Combined Effects of Different Water and Phosphate Levels on Growth and Biological Nitrogen Fixation of Nine Cowpea Varieties

Directory of Open Access Journals (Sweden)

Martin Jemo

2017-12-01

Full Text Available Water deficit and phosphate (Pi deficiency adversely affect growth and biological nitrogen fixation (BNF of legume crops. In this study, we examined the impact of interaction between soil water conditions and available soil-Pi levels on growth, nodule development and BNF potential of nine cowpea varieties grown on dry savanna soils. In our experimental design, soils with different available soil-Pi levels, i.e., low, moderate, and high soil-Pi levels, collected from various farming fields were used to grow nine cowpea varieties under well-watered and water-deficit conditions. Significant and severe water deficit-damaging effects on BNF, nodulation, growth, levels of plant-nitrogen (N and -phosphorus (P, as well as shoot relative water content and chlorophyll content of cowpea plants were observed. Under well-watered and high available soil-Pi conditions, cowpea varieties IT07K-304-9 and Dan'Ila exhibited significantly higher BNF potential and dry biomass, as well as plant-N and -P contents compared with other tested ones. Significant genotypic variations among the cowpeas were recorded under low available soil-Pi and water-deficit conditions in terms of the BNF potential. Principal component (PC analysis revealed that varieties IT04K-339-1, IT07K-188-49, IT07K-304-9, and IT04K-405-5 were associated with PC1, which was better explained by performance for nodulation, plant biomass, plant-N, plant-P, and BNF potential under the combined stress of water deficit and Pi deficiency, thereby offering prospects for development of varieties with high growth and BNF traits that are adaptive to such stress conditions in the region. On another hand, variety Dan'Ila was significantly related to PC2 that was highly explained by the plant shoot/root ratio and chlorophyll content, suggesting the existence of physiological and morphological adjustments to cope with water deficit and Pi deficiency for this particular variety. Additionally, increases in soil

Strategies for Developing Drought Tolerant Cowpea varieties for the Semi-Arid regions of Nigeria

International Nuclear Information System (INIS)

Ishiyaku, M. F.

2000-10-01

Drought, meaning the deviation of the total amount and or distribution of precipitation from the normal is an important factor that cause untold human suffering as well as social and economic loss for any nation. Its effects are often felt by places so remote from the area of occurrence. In the agricultural sector, where its effect are most felt, drought risk greatly reduce investment in agriculture. This will no doubt contribute to national food insecurity and social unrest. Of the measures often prescribed to combat the menace of drought include the development and planting of drought resistant/tolerant crop varieties. This paper discusses the strategies for developing drought tolerant cowpea varieties for the drought-prone regions of Nigeria. These strategies include the introduction and screening of candidate drought tolerant cowpea germplasm and their utilization in developing new improved genotypes. The screening of populations will be carried out by adopting novel screening techniques in the lab as well as in the field. In addition to utilizing existing genetic variation to develop varieties with tolerance to drought, new sources of variation will be created artificially for the various traits known to confer tolerance to drought in cowpea. In creating genetic variability for drought tolerance traits artificially, the potential of irradiation induced mutation will be exploited

Diversity in 113 cowpea [Vigna unguiculata (L) Walp] accessions assessed with 458 SNP markers.

Science.gov (United States)

Egbadzor, Kenneth F; Ofori, Kwadwo; Yeboah, Martin; Aboagye, Lawrence M; Opoku-Agyeman, Michael O; Danquah, Eric Y; Offei, Samuel K

2014-01-01

Single Nucleotide Polymorphism (SNP) markers were used in characterization of 113 cowpea accessions comprising of 108 from Ghana and 5 from abroad. Leaf tissues from plants cultivated at the University of Ghana were genotyped at KBioscience in the United Kingdom. Data was generated for 477 SNPs, out of which 458 revealed polymorphism. The results were used to analyze genetic dissimilarity among the accessions using Darwin 5 software. The markers discriminated among all of the cowpea accessions and the dissimilarity values which ranged from 0.006 to 0.63 were used for factorial plot. Unexpected high levels of heterozygosity were observed on some of the accessions. Accessions known to be closely related clustered together in a dendrogram drawn with WPGMA method. A maximum length sub-tree which comprised of 48 core accessions was constructed. The software package structure was used to separate accessions into three groups, and the programme correctly identified varieties that were known hybrids. The hybrids were those accessions with numerous heterozygous loci. The structure plot showed closely related accessions with similar genome patterns. The SNP markers were more efficient in discriminating among the cowpea germplasm than morphological, seed protein polymorphism and simple sequence repeat studies reported earlier on the same collection.

Genome resources for climate-resilient cowpea, an essential crop for food security.

Science.gov (United States)

Muñoz-Amatriaín, María; Mirebrahim, Hamid; Xu, Pei; Wanamaker, Steve I; Luo, MingCheng; Alhakami, Hind; Alpert, Matthew; Atokple, Ibrahim; Batieno, Benoit J; Boukar, Ousmane; Bozdag, Serdar; Cisse, Ndiaga; Drabo, Issa; Ehlers, Jeffrey D; Farmer, Andrew; Fatokun, Christian; Gu, Yong Q; Guo, Yi-Ning; Huynh, Bao-Lam; Jackson, Scott A; Kusi, Francis; Lawley, Cynthia T; Lucas, Mitchell R; Ma, Yaqin; Timko, Michael P; Wu, Jiajie; You, Frank; Barkley, Noelle A; Roberts, Philip A; Lonardi, Stefano; Close, Timothy J

2017-03-01

Cowpea (Vigna unguiculata L. Walp.) is a legume crop that is resilient to hot and drought-prone climates, and a primary source of protein in sub-Saharan Africa and other parts of the developing world. However, genome resources for cowpea have lagged behind most other major crops. Here we describe foundational genome resources and their application to the analysis of germplasm currently in use in West African breeding programs. Resources developed from the African cultivar IT97K-499-35 include a whole-genome shotgun (WGS) assembly, a bacterial artificial chromosome (BAC) physical map, and assembled sequences from 4355 BACs. These resources and WGS sequences of an additional 36 diverse cowpea accessions supported the development of a genotyping assay for 51 128 SNPs, which was then applied to five bi-parental RIL populations to produce a consensus genetic map containing 37 372 SNPs. This genetic map enabled the anchoring of 100 Mb of WGS and 420 Mb of BAC sequences, an exploration of genetic diversity along each linkage group, and clarification of macrosynteny between cowpea and common bean. The SNP assay enabled a diversity analysis of materials from West African breeding programs. Two major subpopulations exist within those materials, one of which has significant parentage from South and East Africa and more diversity. There are genomic regions of high differentiation between subpopulations, one of which coincides with a cluster of nodulin genes. The new resources and knowledge help to define goals and accelerate the breeding of improved varieties to address food security issues related to limited-input small-holder farming and climate stress. © 2016 The Authors. The Plant Journal published by John Wiley & Sons Ltd and Society for Experimental Biology.

A multi-parent advanced generation inter-cross (MAGIC) population for genetic analysis and improvement of cowpea (Vigna unguiculata L. Walp.).

Science.gov (United States)

Huynh, Bao-Lam; Ehlers, Jeffrey D; Huang, Bevan Emma; Muñoz-Amatriaín, María; Lonardi, Stefano; Santos, Jansen R P; Ndeve, Arsenio; Batieno, Benoit J; Boukar, Ousmane; Cisse, Ndiaga; Drabo, Issa; Fatokun, Christian; Kusi, Francis; Agyare, Richard Y; Guo, Yi-Ning; Herniter, Ira; Lo, Sassoum; Wanamaker, Steve I; Xu, Shizhong; Close, Timothy J; Roberts, Philip A

2018-03-01

Multi-parent advanced generation inter-cross (MAGIC) populations are an emerging type of resource for dissecting the genetic structure of traits and improving breeding populations. We developed a MAGIC population for cowpea (Vigna unguiculata L. Walp.) from eight founder parents. These founders were genetically diverse and carried many abiotic and biotic stress resistance, seed quality and agronomic traits relevant to cowpea improvement in the United States and sub-Saharan Africa, where cowpea is vitally important in the human diet and local economies. The eight parents were inter-crossed using structured matings to ensure that the population would have balanced representation from each parent, followed by single-seed descent, resulting in 305 F 8 recombinant inbred lines each carrying a mosaic of genome blocks contributed by all founders. This was confirmed by single nucleotide polymorphism genotyping with the Illumina Cowpea Consortium Array. These lines were on average 99.74% homozygous but also diverse in agronomic traits across environments. Quantitative trait loci (QTLs) were identified for several parental traits. Loci with major effects on photoperiod sensitivity and seed size were also verified by biparental genetic mapping. The recombination events were concentrated in telomeric regions. Due to its broad genetic base, this cowpea MAGIC population promises breakthroughs in genetic gain, QTL and gene discovery, enhancement of breeding populations and, for some lines, direct releases as new varieties. © 2018 The Authors. The Plant Journal published by John Wiley & Sons Ltd and Society for Experimental Biology.

Electron beam irradiation: laboratory and field studies of cowpea seeds

International Nuclear Information System (INIS)

Srinivasan, K.; Chauhan, S.K.; Prasad, T.V.; Pramod, R.; Verma, V.P.; Petwal, V.; Dwivedi, J.; Bhalla, S.

2015-01-01

Cowpea (Vigna unguiculata) rich in protein and vitamins is emerging as one of the most important food legumes to tackle malnutrition. Pulse beetles (Callosobruchus chinensis and C. maculatus) are the pests of economic importance causing enormous losses during storage. Although various pest management strategies exist for the control of these pests, environmental concerns necessitate developing ecofriendly strategies. Electron beam (EB) irradiation has the potential to be a viable, non-chemical, residue-free strategy for management of pulse beetles during storage, but higher doses affect seed germination and viability. Hence, the present investigation was taken up to analyse the dosage effect of the irradiation on seed attributes of cowpea. Healthy cowpea seeds were irradiated with low energy electrons at different doses viz., 180, 360, 540, 720, 900, 1080, 1260, 1440 and 1620 Gy at 500 keV using the EB Accelerator facility at Raja Ramanna Centre for Advanced Technology, Indore. EB irradiated seeds were tested for physiological viz., germination, seedling vigour and vigour index and biochemical parameters viz., electrical conductivity of seed leachate, seed viability/tetrazolium test and dehydrogenase activity. Germination and vigour of the irradiated seeds were evaluated as per the ISTA Rules (ISTA, 1996). Vigour index was calculated as the product of germination percentage and seedling vigour. About 3,000 irradiated seeds from each dose were grown in the field at the Experimental farm, National Bureau of Plant Genetic Resources, New Delhi. Seeds harvested from 1500 individual plants of M 1 generation from each dose (50 seeds from each plant individually) were sown in next season and observed for chlorophyll mutations, if any. Results revealed that doses upto 1080 Gy (88%) did not affect the germination of cowpea seeds drastically as compared to untreated seeds (98%). Lower doses viz., 180 and 360 Gy had no impact on vigour components while higher doses (1080 Gy

Detection and validation of single feature polymorphisms in cowpea (Vigna unguiculata L. Walp using a soybean genome array

Directory of Open Access Journals (Sweden)

Wanamaker Steve

2008-02-01

Full Text Available Abstract Background Cowpea (Vigna unguiculata L. Walp is an important food and fodder legume of the semiarid tropics and subtropics worldwide, especially in sub-Saharan Africa. High density genetic linkage maps are needed for marker assisted breeding but are not available for cowpea. A single feature polymorphism (SFP is a microarray-based marker which can be used for high throughput genotyping and high density mapping. Results Here we report detection and validation of SFPs in cowpea using a readily available soybean (Glycine max genome array. Robustified projection pursuit (RPP was used for statistical analysis using RNA as a surrogate for DNA. Using a 15% outlying score cut-off, 1058 potential SFPs were enumerated between two parents of a recombinant inbred line (RIL population segregating for several important traits including drought tolerance, Fusarium and brown blotch resistance, grain size and photoperiod sensitivity. Sequencing of 25 putative polymorphism-containing amplicons yielded a SFP probe set validation rate of 68%. Conclusion We conclude that the Affymetrix soybean genome array is a satisfactory platform for identification of some 1000's of SFPs for cowpea. This study provides an example of extension of genomic resources from a well supported species to an orphan crop. Presumably, other legume systems are similarly tractable to SFP marker development using existing legume array resources.

Physicochemical and functional properties of two cowpea cultivars grown in temperate Indian climate

OpenAIRE

Saima Hamid; Sabeera Muzzafar; Idrees Ahmed Wani; Farooq Ahmad Masoodi

2015-01-01

Flours of two local cowpea cultivars namely Red cowpea and Black cowpea were analysed for proximate composition, pasting and functional properties. The crude protein and fat contents were higher for Black cultivar than the Red cultivar. The apparent amylose content was significantly higher for Red cowpea (25.54%) than Black cowpea (15.09%). Polyphenols were significantly higher for Red cowpea than Black cowpea. The pasting profile of two cultivars revealed significantly higher values of peak ...

Alleviating acid soil stress in cowpea with a local population of ...

African Journals Online (AJOL)

Jane

2011-10-24

Oct 24, 2011 ... Arbuscular mycorrhizal fungi from this system have been found to promote ... Total dry weight of inoculated cowpea was not affected by soil acidity while it was ... leaves and fresh fruit, fodder and dry seed (Steele et al.,. 1985).

Influence of fermentation and cowpea steaming on some quality ...

African Journals Online (AJOL)

Fermentation and cowpea steaming can be used to improve the protein quality and quantity of fermented maize dough. In the production of maize-cowpea blends, it is important that the quality characteristics are evaluated to determine their functionality in the products. A 5x4x2x2 factorial experiment with cowpea level, ...

Enhanced Synthesis of Antioxidant Enzymes, Defense Proteins and Leghemoglobin in Rhizobium-Free Cowpea Roots after Challenging with Meloydogine incognita

Directory of Open Access Journals (Sweden)

Jose T. A. Oliveira

2014-11-01

Full Text Available The root knot nematodes (RKN, Meloydogine spp., particularly Meloidogyne incognita and Meloidogyne javanica species, parasitize several plant species and are responsible for large annual yield losses all over the world. Only a few available chemical nematicides are still authorized for RKN control owing to environmental and health reasons. Thus, plant resistance is currently considered the method of choice for controlling RKN, and research performed on the molecular interactions between plants and nematodes to identify genes of interest is of paramount importance. The present work aimed to identify the differential accumulation of root proteins of a resistant cowpea genotype (CE-31 inoculated with M. incognita (Race 3 in comparison with mock-inoculated control, using 2D electrophoresis assay, mass spectrometry identification and gene expression analyses by RT-PCR. The results showed that at least 22 proteins were differentially represented in response to RKN challenge of cowpea roots mainly within 4–6 days after inoculation. Amongst the up-represented proteins were SOD, APX, PR-1, β-1,3-glucanase, chitinases, cysteine protease, secondary metabolism enzymes, key enzymes involved in ethylene biosynthesis, proteins involved in MAPK pathway signaling and, surprisingly, leghemoglobin in non-rhizobium-bacterized cowpea. These findings show that an important rearrangement in the resistant cowpea root proteome occurred following challenge with M. incognita.

Physical and cooking characteristics of two cowpea cultivars grown in temperate Indian climate

OpenAIRE

Saima Hamid; Sabeera Muzaffar; Idrees Ahmed Wani; Farooq Ahmad Masoodi; Mohd. Munaf Bhat

2016-01-01

Two local cowpea cultivars (Red cowpea and Black cowpea) were studied for various physical, cooking and textural properties. The moisture, crude protein, fat, ash and carbohydrate content of seeds ranged from 10.0% to 10.1%, 21.29–23.90%, 0.49–1.94%, 19.8–2.81%, and 60.53–62.45%, respectively. Sphericity, 1000-seed weight and surface area were significantly higher for Red cowpea than Black cowpea. However bulk density was found significantly higher for Black cowpea than Red cowpea. Black cowp...

Estimating the Broad-Sense Heritability of Early Growth of Cowpea

OpenAIRE

Xu, Nicole W.; Xu, Shizhong; Ehlers, Jeff

2009-01-01

Cowpea is an important tropical crop. It provides a large proportion of the food resource for the African human population and their livestock. The yield and quality of cowpea have been dramatically improved through traditional breeding strategies for the past few decades. However, reports of heritability estimates for early growth of cowpea are rare. We designed a simple experiment to estimate the broad-sense heritability of early growth. We randomly selected 15 cowpea varieties among a tota...

Physiological and molecular characterization of cowpea [Vigna ...

African Journals Online (AJOL)

Diaga Diouf

Cowpea, Vigna unguiculata (L.) Walp. presents phenotypical variabilities and in order to study the genetic diversity of cultivated Senegalese varieties, two experimental approaches were used. First, a physiological characterization based on nitrogen fixation was used to assess cowpea breeding lines. Inoculation with two ...

Cowpea: a legume crop for a challenging environment.

Science.gov (United States)

Carvalho, Márcia; Lino-Neto, Teresa; Rosa, Eduardo; Carnide, Valdemar

2017-10-01

Cowpea is a grain legume native from Africa and is a primary source of protein for millions of people in sub-Saharan Africa and other parts of the developing world. The main important characteristics of this crop include a good protein quality with a high nutritional value, its nitrogen-fixing ability, and an ability to be more drought- and heat-tolerant than most of its legume relatives. In a research perspective, studies of cowpea are relatively scarce, despite its relevance to agriculture in the developing world and its resilience to stress. The present review provides an overview of different aspects of cowpea, with a special emphasis on the molecular markers for assessing genetic diversity, as well as on biochemical and transcriptomic data with respect to evaluating cowpea drought stress tolerance. The integration of both datasets will be useful for the improvement of cowpea because research on drought stress tolerance is of major interest for this crop in a challenging environment. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Genetic engineering in Cowpea (Vigna unguiculata): history, status and prospects.

Science.gov (United States)

Citadin, Cristiane T; Ibrahim, Abdulrazak B; Aragão, Francisco J L

2011-01-01

In the last three decades, a number of attempts have been made to develop reproducible protocols for generating transgenic cowpea that permit the expression of genes of agronomic importance. Pioneer works focused on the development of such systems vis-à-vis an in vitro culture system that would guarantee de novo regeneration of transgenic cowpea arising from cells amenable to one form of gene delivery system or another, but any such system has eluded researchers over the years. Despite this apparent failure, significant progress has been made in generating transgenic cowpea, bringing researchers much nearer to their goal than thirty years ago. Now, various researchers have successfully established transgenic procedures for cowpea with evidence of inherent transgenes of interest, effected by progenies in a Mendelian fashion. New opportunities have thus emerged to optimize existing protocols and devise new strategies to ensure the development of transgenic cowpea with desirable agronomic traits. This review chronicles the important milestones in the last thirty years that have marked the evolution of genetic engineering of cowpea. It also highlights the progress made and describes new strategies that have arisen, culminating in the current status of transgenic technologies for cowpea.

Isolation of cowpea genes conferring drought tolerance ...

African Journals Online (AJOL)

The main objective of this study was to identify and isolate the genes conferring drought tolerance in cowpea. A cDNA library enriched for cowpea genes expressed specifically during responses to drought was constructed. A procedure called suppression subtractive hybridisation (SSH) was successfully employed to obtain ...

Diallel crosses for resistance to Macrophomina phaseolina and Thanatephorus cucumeris on cowpea.

Science.gov (United States)

Lima, L R L; Damasceno-Silva, K J; Noronha, M A; Schurt, D A; Rocha, M M

2017-09-27

This study aimed at identifying and selecting through partial diallel analysis, segregating populations of cowpea resistant to Macrophomina phaseolina and Thanatephorus cucumeris, based on the evaluation of general (GCA) and specific combining ability (SCA), involved in the genetic control of resistance. For this reason, 19 grouped cowpea genotypes, considering the resistance to these pathogens, were crossed in partial diallel scheme 14 x 5, during 2013 and 2014. The 70 F 2 populations and the 19 parents were evaluated in a greenhouse as the reaction to pathogens, separately. The diallel analysis was performed according to the model of partial diallel proposed by Geraldi and Miranda Filho (1988). The additive effects predominated in the genetic control of the traits severity of charcoal rot (SEV) and area under the disease progress curve (AUDPC) to web blight, enabling the achievement of genetic gain with selection of resistant strains. Analyzing the effects of GCA, the parents BR 14-Mulato, BRS Tumucumaque and BRS Guariba, have a higher concentration of favorable alleles, highlighting, according to the values of SCA, the combinations BR 14-Mulato x MNC02-675F-4-10, BRS Tumucumaque x IT98K-1092-1, BRS Tumucumaque x MNC02-675F-4-10, BRS Tumucumaque x MNC02-675F-9-2, BRS Guariba x IT98K-1092-1, BRS Guariba x MNC02-675F-4-9, and BRS Guariba x MNC02-675F-4-10, as the most promising and indicated to obtain lines resistant to M. phaseolina and T. cucumeris in cowpea, simultaneously.

Influence of carbofuran on certain metabolic and symbiotic activities of a cowpea Rhizobium

International Nuclear Information System (INIS)

Palaniappan, S.; Balasubramanian, A.

1983-01-01

Using carbon 14 radioisotope an in-vitro study of the effect of insecticides, carbofuran, on the metabolic and symbiotic activities of Rhizobium sp. cowpea group, was carried out. The study indicated that at 10 ppm carbofuran inhibited the in-vitro growth of the bacterium, suppressed the oxidation of all the Trichloroacetic acid (TCA) cycle intermediates, significantly reduced glucose oxidation and translocation and affected the growth and symbiotic activities of the cowpea as reflected by a reduction in the dry matter production and total nitrogen content. The insecticide was itself degraded by the Rhizobium sp. within 30 days of incubation

Transgenic plants expressing the coat protein gene of cowpea aphid ...

African Journals Online (AJOL)

Cowpea aphid-borne mosaic virus (CABMV) is a potyvirus that infects cowpea causing significant yield reduction. However, there is no durable natural resistance to the virus within the crop and genetic engineering for virus resistance was not possible because of a lack of an efficient, reliable and reproducible cowpea ...

Yields and protein content of two cowpea varieties grown under ...

African Journals Online (AJOL)

Sole cowpea and sweet corn treatments were included and all treatments replicated four times. Fully expanded cowpea leaves on all cowpea plants in the two middle rows were harvested once at seven weeks after seed sowing prior to flowering. Growth and yield component data were collected from component crops while ...

Effect of gamma radiation on seed germination and seedling vigour in cowpea [Vigna unguiculata (L.) Walp.

International Nuclear Information System (INIS)

Thimmaiah, S.K.; Mahadevu, P; Srinivasappa, K.N.; Shankara, A.N.

1998-01-01

Cowpea [Vigna unguiculata (L.) Walp.) is regarded as hardy and one of the important tropical legumes. The plants respond differently to mutagenic treatments. Ionizing radiations affect a wide range of physiological and biochemical activities of plants. The purpose of this paper is to report the effect of gamma radiation on seed germination and seedling vigour of two important cowpea varieties viz., KBC-1 and TVX-994-02E in M 1 generation under laboratory conditions. (author)

Diallelic analysis to obtain cowpea (Vigna unguiculata L. Walp.) populations tolerant to water deficit.

Science.gov (United States)

Rodrigues, E V; Damasceno-Silva, K J; Rocha, M M; Bastos, E A

2016-05-13

The purpose of this study was to identify parents and obtain segregating populations of cowpea (Vigna unguiculata L. Walp.) with the potential for tolerance to water deficit. A full diallel was performed with six cowpea genotypes, and two experiments were conducted in Teresina, PI, Brazil in 2011 to evaluate 30 F2 populations and their parents, one under water deficit and the other under full irrigation. A triple-lattice experimental design was used, with six 2-m-long rows in each plot. Sixteen plants were sampled per plot. The data were subjected to analysis of variance, and general and specific combining ability estimates were obtained based on the means. Additive effects were more important than non-additive effects, and maternal inheritance had occurred. The genotypes BRS Xiquexique, Pingo de Ouro-1-2, and MNC99-510F-16-1 were the most promising for use in selection programs aimed at water deficit tolerance. The hybrid combinations Pingo de Ouro-1-2 x BRS Xiquexique, BRS Xiquexique x Santo Inácio, CNCx 698-128G x MNC99-510F-16-1, Santo Inácio x CNCx 698-128G, MNC99-510F-16-1 x BRS Paraguaçu, MNC99- 510F-16-1 x Pingo de Ouro-1-2, and MNC99-510F-16-1 x BRS Xiquexique have the potential to increase grain production and tolerate water deficit.

Ethics and quality assessment of cowpea grains sold in southern ...

African Journals Online (AJOL)

The study examined the supply side of cowpea markets in two states of Nigeria. Specifically, quality status; grades of cowpea grains sold and effect of ethics on sales, quality and price were determined. A multi-stage sampling technique was used to select four hundred cowpea grain sellers in the study areas. Questionnaire ...

Genetic variability of indigenous cowpea genotypes as determined ...

African Journals Online (AJOL)

Bayesian statistics coupled with the Markov chain Monte Carlo technique was applied to determine population structure, while the genetic variability was established by analysis of molecular variance. UPGMA analysis allowed the separation of the genotypes into three groups, but no relationship between the genetic and ...

Metagenomic-Based Screening and Molecular Characterization of Cowpea-Infecting Viruses in Burkina Faso.

Science.gov (United States)

Palanga, Essowè; Filloux, Denis; Martin, Darren P; Fernandez, Emmanuel; Gargani, Daniel; Ferdinand, Romain; Zabré, Jean; Bouda, Zakaria; Neya, James Bouma; Sawadogo, Mahamadou; Traore, Oumar; Peterschmitt, Michel; Roumagnac, Philippe

2016-01-01

Cowpea, (Vigna unguiculata L. (Walp)) is an annual tropical grain legume. Often referred to as "poor man's meat", cowpea is one of the most important subsistence legumes cultivated in West Africa due to the high protein content of its seeds. However, African cowpea production can be seriously constrained by viral diseases that reduce yields. While twelve cowpea-infecting viruses have been reported from Africa, only three of these have so-far been reported from Burkina Faso. Here we use a virion-associated nucleic acids (VANA)-based metagenomics method to screen for the presence of cowpea viruses from plants collected from the three agro-climatic zones of Burkina Faso. Besides the three cowpea-infecting virus species which have previously been reported from Burkina Faso (Cowpea aphid borne mosaic virus [Family Potyviridae], the Blackeye cowpea mosaic virus-a strain of Bean common mosaic virus-[Family Potyviridae] and Cowpea mottle virus [Family Tombusviridae]) five additional viruses were identified: Southern cowpea mosaic virus (Sobemovirus genus), two previously uncharacterised polerovirus-like species (Family Luteoviridae), a previously uncharacterised tombusvirus-like species (Family Tombusviridae) and a previously uncharacterised mycotymovirus-like species (Family Tymoviridae). Overall, potyviruses were the most prevalent cowpea viruses (detected in 65.5% of samples) and the Southern Sudan zone of Burkina Faso was found to harbour the greatest degrees of viral diversity and viral prevalence. Partial genome sequences of the two novel polerovirus-like and tombusvirus-like species were determined and RT-PCR primers were designed for use in Burkina Faso to routinely detect all of these cowpea-associated viruses.

Metagenomic-Based Screening and Molecular Characterization of Cowpea-Infecting Viruses in Burkina Faso.

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Essowè Palanga

Full Text Available Cowpea, (Vigna unguiculata L. (Walp is an annual tropical grain legume. Often referred to as "poor man's meat", cowpea is one of the most important subsistence legumes cultivated in West Africa due to the high protein content of its seeds. However, African cowpea production can be seriously constrained by viral diseases that reduce yields. While twelve cowpea-infecting viruses have been reported from Africa, only three of these have so-far been reported from Burkina Faso. Here we use a virion-associated nucleic acids (VANA-based metagenomics method to screen for the presence of cowpea viruses from plants collected from the three agro-climatic zones of Burkina Faso. Besides the three cowpea-infecting virus species which have previously been reported from Burkina Faso (Cowpea aphid borne mosaic virus [Family Potyviridae], the Blackeye cowpea mosaic virus-a strain of Bean common mosaic virus-[Family Potyviridae] and Cowpea mottle virus [Family Tombusviridae] five additional viruses were identified: Southern cowpea mosaic virus (Sobemovirus genus, two previously uncharacterised polerovirus-like species (Family Luteoviridae, a previously uncharacterised tombusvirus-like species (Family Tombusviridae and a previously uncharacterised mycotymovirus-like species (Family Tymoviridae. Overall, potyviruses were the most prevalent cowpea viruses (detected in 65.5% of samples and the Southern Sudan zone of Burkina Faso was found to harbour the greatest degrees of viral diversity and viral prevalence. Partial genome sequences of the two novel polerovirus-like and tombusvirus-like species were determined and RT-PCR primers were designed for use in Burkina Faso to routinely detect all of these cowpea-associated viruses.

Performance of cowpea grown as an intercrop with maize of different ...

African Journals Online (AJOL)

The negative effects of shade were more pronounced in the semi-determinate cowpea than in the indeterminate. Therefore, in high maize populations, indeterminate spreading cowpeas should be grown; while semi-determinate cowpeas should be planted in low to moderate maize populations because of their intolerance ...

Effects of Cropping System and Cowpea Variety on Symbiotic Potential and Yields of Cowpea (Vigna unguiculata L. Walp and Pearl Millet (Pennisetum glaucum L. in the Sudano-Sahelian Zone of Mali

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Zoumana Kouyaté

2012-01-01

Full Text Available Many cowpea varieties (Vigna unguiculata L. Walp have been proposed by research in Mali. None of these varieties were investigated for their symbiotic potential in terms of root nodulation and mycorrhizal infection. An experiment was conducted at Cinzana Research Station, from 2007 to 2009 with an objective to identify a cowpea variety with high symbiotic potential which may improve millet/cowpea cropping global production. Randomized complete block (RCBD design with a factorial combination of 3 cowpea varieties (IT89KD-374, CZ1-94-23-1, and CZ11-94-5C and 2 cropping systems (millet/cowpea intercropping and cowpea-millet rotation was used. On farm test was conducted to evaluate CZ11-94-5C and IT89KD-374 nodulation performance. Cowpea variety CZ11-94-5-C had the highest nodule number and nodule weight. Millet/cowpea alternate rows intercropping (1/1, only, had a significant influence on cowpea root infection rates by mycorrhizae, on the 45th day after emergence. IT89KD-374 gave the best cowpea grain yield (1540 kg ha−1 in sole crop. The highest millet grain yield (1650 kg ha−1 was obtained under CZ11-94-5C-millet rotation. Farmers' fields assessments results confirmed CZ11-94-5C performance on research station. The CZ11-94-5C cowpea variety needs to be more characterized.

Control of Cowpea Weevil, Callosobruchus Maculatus (F.) (Coleoptera: Bruchidae), Using Natural Plant Products

OpenAIRE

Tiroesele, Bamphitlhi; Thomas, Kesegofetse; Seketeme, Seipati

2014-01-01

A laboratory study was conducted to investigate the effects of natural products on the reproduction and damage of Callosobruchus maculatus, the cowpea weevil, on cowpea seeds at Botswana College of Agriculture in Gaborone, Botswana. The cowpea variety Blackeye was used in the study. Fifty grams of each plant product (garlic, peppermint and chilies) was added to 500 g of the cowpea seeds. Findings of this experiment revealed that chilies and garlic had negative effects on cowpea weevils for al...

Yield and water use efficiencies of maize and cowpea as affected by tillage and cropping systems in semi-arid Eastern Kenya

International Nuclear Information System (INIS)

Miriti, M.J; Kironchi, G; Gachene, K.K.C; Esilaba, O.A.; Mwangi, M.D; Heng, K.L

2012-01-01

Soil water conservation through tillage is widely accepted as one of the ways of improving crop yields in rainfed agriculture. Field experiments were conducted between 2007 and 2009 to evaluate the effects of conservation tillage on the yields and crop water use efficiency of maize (Zea mays L.) and cowpea (Vigna unguiculata L.) in eastern Kenya. Experimental treatments were a combination of three tillage practices and four cropping systems. Tillage practices were tied-ridges, subsoiling-ripping and ox-ploughing. The cropping systems were single crop maize, single crop cowpea, intercropped maize.cowpea and single crop maize with manure. The treatments were arranged in split plots with tillage practices as the main plots and cropping systems as the sub-plots in a Randomized Complete Block Design (RCBD). The results showed that tied-ridge tillage had the greatest plant available water content while subsoiling-ripping tillage had the least in all seasons. Averaged across seasons and cropping season, tillage did not have a significant effects on maize grain yield but it did have a significant effect on crop grain and dry matter water use efficiency (WUE). Nevertheless, maize grain yields and WUE values were generally greater under tied-ridge tillage than under subsoiling-ripping and ox-plough tillages. The yields and WUE of cowpea under subsoiling-ripping tillage were less than those of ox-plough tillage. When averaged across the seasons and tillage systems, the cropping system with the manure treatment increased (P.0.05) maize grain yield, grain WUE and dry matter WUE by 36%, 30%, 26% respectively, compared to treatments without manure. Maize and cowpea when intercropped under ox-plough and ripping tillage systems did not have any yield advantage over the single crop

DETERMINATION OF THE EFFICACY OF BEST ACTION, FURADAN, AND NEEM EMULSION IN THE CONTROL OF MAJOR INSECT PESTS OF COWPEA [Vigna unguiculata (L. WALP

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2016-11-01

Full Text Available Field experiments to determine the efficacy of Best Action (30g/litre cypermethrine plus 250g/litre dimethoate as water emulsifiable concentrates, Furadan 10G (carbofuran, Neem emulsion (Azadiracta indica as insecticide treatments in the control of major insect pests of cowpea were conducted in two agro-environments simultaneously in Enugu Area, South Eastern Nigeria in 2014 cropping season using two cowpea varieties (Ife brown, and Potiskum as test crops. The experimental design was a split plot in a randomized compete block (RCB replicated three times. Best Action was more effective in controlling cowpea insect pests, followed by Furandan 10G, and Neem emulsion respectively and their effectiveness was not affected by climatic factors variations in the two agro-environments (Nsukka and Agbani. Ife brown and Potiskum did not significantly resist the attack of major insect pests of cowpea. Insecticides and cowpea varieties did not have a significant interaction effect on the control of major insect pests of cowpea.

Bioactive metabolites in improved cowpea seeds | Ameen | African ...

African Journals Online (AJOL)

The International Institute of Tropical Agriculture (IITA) has developed some pest and disease resistant cowpeas. From these the seeds of 8 cowpea cultivars were extracted with ethanol, and partitioned into chloroform and water-soluble fractions, the water-soluble fraction was further extracted with ethyl acetate. Residues ...

Cowpea production as affected by dry spells in no-tillage and conventional crop systems

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Rômulo Magno Oliveira de Freitas

2013-12-01

Full Text Available The objective of this study was to evaluate the effect of different periods of water shortage in no-tillage and conventional crop systems on cowpea yield components and grain yield in the Mossoró-RN region. For this, an experiment was conducted using two tillage systems (conventional and no-tillage subjected to periods of irrigation suspension (2; 6; 10; 14; 18 end 22 days, started at flowering (34 days after sowing. Plants were harvested 70 days after sowing, and the studied variables were: Pods length (CV, number of grains per pod (NGV, number of pods per plant (NPP, the hundred grains weight (PCG and grain yield (kg ha-1. The no-tillage system is more productive than the conventional under both irrigation and water stress treatments. The water stress length affected grain yield and all yield components studied in a negative way, except for the hundred grains weight. Among the systems studied, the no-tillage provides higher values for the yield components, except the hundred grains weight.

Production and characterization of cowpea protein hydrolysate with optimum nitrogen solubility by enzymatic hydrolysis using pepsin.

Science.gov (United States)

Mune Mune, Martin Alain; Minka, Samuel René

2017-06-01

Cowpea is a source of low-cost and good nutritional quality protein for utilization in food formulations in replacement of animal proteins. Therefore it is necessary that cowpea protein exhibits good functionality, particularly protein solubility which affects the other functional properties. The objective of this study was to produce cowpea protein hydrolysate exhibiting optimum solubility by the adequate combination of hydrolysis parameters, namely time, solid/liquid ratio (SLR) and enzyme/substrate ratio (ESR), and to determine its functional properties and molecular characteristics. A Box-Behnken experimental design was used for the experiments, and a second-order polynomial to model the effects of hydrolysis time, SLR and ESR on the degree of hydrolysis and nitrogen solubility index. The optimum hydrolysis conditions of time 208.61 min, SLR 1/15 (w/w) and ESR 2.25% (w/w) yielded a nitrogen solubility of 75.71%. Protein breakdown and the peptide profile following enzymatic hydrolysis were evaluated by sodium dodecyl sulfate polyacrylamide gel electrophoresis and size exclusion chromatography. Cowpea protein hydrolysate showed higher oil absorption capacity, emulsifying activity and foaming ability compared with the concentrate. The solubility of cowpea protein hydrolysate was adequately optimized by response surface methodology, and the hydrolysate showed adequate functionality for use in food. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Assessment of the polytank for fumigation and storage of cowpea

International Nuclear Information System (INIS)

Ademang Korletey, Francis

2009-06-01

Insect infestation of cowpea (Vigna unguiculata) in storage is identified as a major constraint facing cowpea farmers in Ghana. The major insect pest causing losses to stored cowpea in West Africa is the cowpea weevil (Callosobruchus maculatus). Fumigation is the most effective control method against cowpea weevil considering its mode of infestation. The jute sack lined with a plastic film bag commonly used by farmers for fumigation and storage is very delicate to handle, not sufficiently airtight for fumigation and easily attacked by rodents. The objectives of the project were to (1) assess the polytank for fumigation and storage of cowpea, and (2) compare the storage qualities of stored cowpea using the polytank and jute sack lined with a plastic film bag. The cowpea was fumigated using aluminium phosphide tablets for a period of 7 days and stored for six mouths. Data was collected, analysed and compared between the two storage containers on seed germination, seed vigour, grain moisture content, insect infestation, percentage usable proportion by number and by weight before, mid-storage and after the trial. The levels of phosphine gas concentration in the polytank and the jute sack were assessed daily for 7 days. The results showed no significant differences (1% probability) between the two storage containers in their performance as storage containers in terms of grain moisture content, seed germination, seed vigour, insect infestation, percentage usable proportion by number and by weight. There was also significant difference (5%) in phosphine gas concentration between the two storage containers in their performance as fumigation containers except on day one. However, it was found that fumigation and storage using the polytank had a greater advantage over the jute sack lined with plastic film bag in terms of air tightness, handling and resistance to rodent attacks. (au)

Highly distinct chromosomal structures in cowpea (Vigna unguiculata), as revealed by molecular cytogenetic analysis.

Science.gov (United States)

Iwata-Otsubo, Aiko; Lin, Jer-Young; Gill, Navdeep; Jackson, Scott A

2016-05-01

Cowpea (Vigna unguiculata (L.) Walp) is an important legume, particularly in developing countries. However, little is known about its genome or chromosome structure. We used molecular cytogenetics to characterize the structure of pachytene chromosomes to advance our knowledge of chromosome and genome organization of cowpea. Our data showed that cowpea has highly distinct chromosomal structures that are cytologically visible as brightly DAPI-stained heterochromatic regions. Analysis of the repetitive fraction of the cowpea genome present at centromeric and pericentromeric regions confirmed that two retrotransposons are major components of pericentromeric regions and that a 455-bp tandem repeat is found at seven out of 11 centromere pairs in cowpea. These repeats likely evolved after the divergence of cowpea from common bean and form chromosomal structure unique to cowpea. The integration of cowpea genetic and physical chromosome maps reveals potential regions of suppressed recombination due to condensed heterochromatin and a lack of pairing in a few chromosomal termini. This study provides fundamental knowledge on cowpea chromosome structure and molecular cytogenetics tools for further chromosome studies.

Viral protein synthesis in cowpea mosaic virus infected protoplasts

International Nuclear Information System (INIS)

Rottier, P.

1980-01-01

Some aspects of cowpea mosaic virus (CPMV) multiplication in cowpea mesophyll protoplasts were studied. The detection and characterization of proteins whose synthesis is induced or is stimulated upon virus infection was performed with the aid of radioactive labelling. (Auth.)

Inheritanceof seed coat colour pattern in cowpea [ Vigna ...

African Journals Online (AJOL)

Hybridization experiments were conducted in the screen house to study the inheritance of seed colour pattern in cowpea. Cowpea varieties of varying seed coat colour were used as parents for the investigation. Parental, F1 and segregating F2 populations were raised in the field and the study revealed that self colour ...

Application of response surface methodology for studying the product characteristics of extruded rice-cowpea-groundnut blends.

Science.gov (United States)

Asare, Emmanuel Kwasi; Sefa-Dedeh, Samuel; Sakyi-Dawson, Esther; Afoakwa, Emmanuel Ohene

2004-08-01

Response surface methodology (with central composite rotatable design for k=3) was used to investigate the product properties of extruded rice-cowpea-groundnut blends in a single screw extruder. The combined effect of cowpea (0-20%), groundnut (0-10%), and feed moisture (14-48%) levels were used for formulation of the products. The product moisture, expansion ratio, bulk density and total colour change were studied using standard analytical methods. Well-expanded rice-legume blend extrudates of less bulk density and lower moisture content were produced at low feed moisture. Increasing legume addition affected the various shades of colour in the product. Models developed for the indices gave R(2) values ranging from 52.8% (for the b-value) to 86.5% (for bulk density). The models developed suggested that the optimal process variables for the production of a puffed snack with an enhanced nutrition and spongy structure from a rice-cowpea-groundnut blend are low feed moisture of 14-20% and maximum additions of 20% cowpea and 10% groundnut. A lack-of-fit test showed no significance, indicating that the models adequately fitted the data.

Heavy metals and yield of cowpea cultivated under composted tannery sludge amendment

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Iuna Carmo Ribeiro Gonçalves

2014-04-01

Full Text Available The study aimed to evaluate the phytoavailability of heavy metals (Cr, Cd, Ni and Pb concentrations in leaves and grains, and yield of cowpea (Vigna unguiculata L grown in soil amended with composted tannery sludge (CTS for two consecutive years. The experiments were carried out in 2009 and 2010 in soil amended with CTS at 0, 5, 10, 20, and 40 Mg ha-1. The CTS amendment rates applied were above 10 Mg ha-1, increased Cr concentrations in cowpea leaves. There were not increases in the heavy metals concentrations in cowpea grains after two years. In 2009, the application of CTS amendment did not promote increase in plant yield. However, in 2010, CTS amendment at 10 and 20 Mg ha-1 increased cowpea yield. The amendment of composted tannery sludge linearly increased linearly the concentration of Cr in the leaves of cowpea after two years. Composted tannery sludge promoted increases in cowpea yield.

Microbiology of natural fermentation of cowpea and groundnut for ...

African Journals Online (AJOL)

Traditionally, locustbean is fermented naturally for dawadawa production. Scarcity of locustbean indicated a need for using other legumes as substitutes for producing dawadawa. The feasibility of using cowpea and groundnut was therefore investigated. The microorganisms associated with natural fermentation of cowpea ...

Use of two varieties of hard-to-cook beans (Phaseolus vulgaris) and cowpeas (Vigna unguiculata) in the processing of koki (a steamed legume product).

Science.gov (United States)

Mbofung, C M; Rigby, N; Waldron, K

1999-01-01

Koki is a nutritious cowpea-based food product usually processed by steam cooking whipped cowpea (Vigna unguiculata) paste mixed with spices and palm oil. A study was carried out to investigate the effect of the partial replacement of cowpeas (CP) with hard-to-cook (HTC) beans on the chemical, nutritional and sensory characteristics of koki. Towards this objective, two varieties of beans--Phaseolus vulgaris (red kidney beans--RKB and mottled brown beans--MBB), each with the HTC defect, were separately incorporated into cowpea paste in the following Bean:CP ratios 0:100, 20:80, 30:70, 40:60, 50:50, 60:40 and processed into koki. Incorporation of dry HTC beans into cowpeas in the making of koki affected the bulking properties of the uncooked paste, the nutrient composition, essential amino acid content, antinutritional factors, digestibility as well as the sensory attributes of cooked koki. Sensory tests showed that a highly acceptable, nutritious and digestible koki can be processed from cowpeas partially replaced with dry HTC bean paste up to levels of about 40-50% depending on the variety of dry bean used.

Susceptibility Of Five Cowpea ( Vigna unguiculata ) Varieties To ...

African Journals Online (AJOL)

Susceptibility Of Five Cowpea ( Vigna unguiculata ) Varieties To Attack By Callosobruchus maculatus (Fab.) ... in Ghana were screened for susceptibility to the cowpea beetle, C. maculatus, in storage for a period of 30 days in the laboratory at an ambient temperature of 27.5 ± 0.9oC and relative humidity of 64.6 ± 2%.

Sequencing and analysis of the gene-rich space of cowpea

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Cheung Foo

2008-02-01

Full Text Available Abstract Background Cowpea, Vigna unguiculata (L. Walp., is one of the most important food and forage legumes in the semi-arid tropics because of its drought tolerance and ability to grow on poor quality soils. Approximately 80% of cowpea production takes place in the dry savannahs of tropical West and Central Africa, mostly by poor subsistence farmers. Despite its economic and social importance in the developing world, cowpea remains to a large extent an underexploited crop. Among the major goals of cowpea breeding and improvement programs is the stacking of desirable agronomic traits, such as disease and pest resistance and response to abiotic stresses. Implementation of marker-assisted selection and breeding programs is severely limited by a paucity of trait-linked markers and a general lack of information on gene structure and organization. With a nuclear genome size estimated at ~620 Mb, the cowpea genome is an ideal target for reduced representation sequencing. Results We report here the sequencing and analysis of the gene-rich, hypomethylated portion of the cowpea genome selectively cloned by methylation filtration (MF technology. Over 250,000 gene-space sequence reads (GSRs with an average length of 610 bp were generated, yielding ~160 Mb of sequence information. The GSRs were assembled, annotated by BLAST homology searches of four public protein annotation databases and four plant proteomes (A. thaliana, M. truncatula, O. sativa, and P. trichocarpa, and analyzed using various domain and gene modeling tools. A total of 41,260 GSR assemblies and singletons were annotated, of which 19,786 have unique GenBank accession numbers. Within the GSR dataset, 29% of the sequences were annotated using the Arabidopsis Gene Ontology (GO with the largest categories of assigned function being catalytic activity and metabolic processes, groups that include the majority of cellular enzymes and components of amino acid, carbohydrate and lipid metabolism. A

Intercropping maize with cassava or cowpea in Ghana | Ennin ...

African Journals Online (AJOL)

Maize/cassava and maize/cowpea intercrops were evaluated in southern Ghana, over a 5-year period to determine the optimum combination of component crop varieties and component plant population densities to optimize productivity of maize-based intercropping systems. Results indicated that some cowpea varieties ...

Genetic variability and resistance of cultivars of cowpea [Vigna unguiculata (L.) Walp] to cowpea weevil (Callosobruchus maculatus Fabr.).

Science.gov (United States)

Vila Nova, M X; Leite, N G A; Houllou, L M; Medeiros, L V; Lira Neto, A C; Hsie, B S; Borges-Paluch, L R; Santos, B S; Araujo, C S F; Rocha, A A; Costa, A F

2014-03-31

The cowpea weevil (Callosobruchus maculatus Fabr.) is the most destructive pest of the cowpea bean; it reduces seed quality. To control this pest, resistance testing combined with genetic analysis using molecular markers has been widely applied in research. Among the markers that show reliable results, the inter-simple sequence repeats (ISSRs) (microsatellites) are noteworthy. This study was performed to evaluate the resistance of 27 cultivars of cowpea bean to cowpea weevil. We tested the resistance related to the genetic variability of these cultivars using ISSR markers. To analyze the resistance of cultivars to weevil, a completely randomized test design with 4 replicates and 27 treatments was adopted. Five pairs of the insect were placed in 30 grains per replicate. Analysis of variance showed that the number of eggs and emerged insects were significantly different in the treatments, and the means were compared by statistical tests. The analysis of the large genetic variability in all cultivars resulted in the formation of different groups. The test of resistance showed that the cultivar Inhuma was the most sensitive to both number of eggs and number of emerged adults, while the TE96-290-12-G and MNC99-537-F4 (BRS Tumucumaque) cultivars were the least sensitive to the number of eggs and the number of emerged insects, respectively.

Gas exchange and mass distribution of the cowpea (Vigna unguiculata [L.] Walp. under water deficit

Directory of Open Access Journals (Sweden)

Cardona-Ayala Carlos Enrique

2013-12-01

Full Text Available Drought tolerance is important for the survival and productivity of plants in environments where drought periods are increasing as a result of climate variability attributable to natural causes and climate change caused by human activities. The objective of this study was to evaluate the dynamics of photosynthesis (A, stomatal conductance (gs and intrinsic water-use efficiency (WUE=A/gs as a function of soil moisture content over a period of drought and the post-stress recovery of 14 cowpea genotypes. The studied genotypes tolerated soil moisture tensions close to -2 Mpa with no permanent wilting. Starting at a soil hydric potential of -0.7 MP a, decreases in photosynthesis (A, stomatal conductance (gs and transpiration (E were evident, as well as an increase in A/gs, which varied by genotype. Estimating with regression models allowed for the discrimination of the degrees of drought tolerance between the cultivars. At 4 days after resuming hydration, no significant differences were found between the means of A, gs, A/gs and E, suggesting drought tolerance in all genotypes. The genotypes: L-047 and L-034 conserved between 4 and 6 leaves, displaying the highest delayed leaf senescence during drought. Furthermore, they presented the highest biomass at 16 days post-stress recovery

Effect Of Cowpea Planting Density On Growth, Yield And ...

African Journals Online (AJOL)

Effect Of Cowpea Planting Density On Growth, Yield And Productivity Of Component Crops In Cowpea/Cassava Intercropping System. ... Similarly, fresh root yield (t/ha) of cassava was influenced by cropping system and population density in 2005/2006, but not in 2004/2005 cropping season. Cassava tuber yield was ...

RNAi-derived transgenic resistance to Mungbean yellow mosaic India virus in cowpea.

Science.gov (United States)

Kumar, Sanjeev; Tanti, Bhaben; Patil, Basavaprabhu L; Mukherjee, Sunil Kumar; Sahoo, Lingaraj

2017-01-01

Cowpea is an important grain legume crop of Africa, Latin America, and Southeast Asia. Leaf curl and golden mosaic diseases caused by Mungbean yellow mosaic India virus (MYMIV) have emerged as most devastating viral diseases of cowpea in Southeast Asia. In this study, we employed RNA interference (RNAi) strategy to control cowpea-infecting MYMIV. For this, we generated transgenic cowpea plants harbouring three different intron hairpin RNAi constructs, containing the AC2, AC4 and fusion of AC2 and AC4 (AC2+AC4) of seven cowpea-infecting begomoviruses. The T0 and T1 transgenic cowpea lines of all the three constructs accumulated transgene-specific siRNAs. Transgenic plants were further assayed up to T1 generations, for resistance to MYMIV using agro-infectious clones. Nearly 100% resistance against MYMIV infection was observed in transgenic lines, expressing AC2-hp and AC2+AC4-hp RNA, when compared with untransformed controls and plants transformed with empty vectors, which developed severe viral disease symptoms within 3 weeks. The AC4-hp RNA expressing lines displayed appearance of milder symptoms after 5 weeks of MYMIV-inoculation. Northern blots revealed a positive correlation between the level of transgene-specific siRNAs accumulation and virus resistance. The MYMIV-resistant transgenic lines accumulated nearly zero or very low titres of viral DNA. The transgenic cowpea plants had normal phenotype with no yield penalty in greenhouse conditions. This is the first demonstration of RNAi-derived resistance to MYMIV in cowpea.

Additive interactions of unrelated viruses in mixed infections of cowpea.

Directory of Open Access Journals (Sweden)

Imade Yolanda Nsa

2015-10-01

Full Text Available This study was carried out to determine the effects of single infections and co-infections of three unrelated viruses on three cowpea cultivars (one commercial cowpea cultivar White and 2 IITA lines; IT81D-985 and TVu76. The plants were inoculated with Cowpea aphid-borne mosaic virus (CABMV, genus Potyvirus, Cowpea mottle virus (CMeV, genus Carmovirus and Southern bean mosaic virus (SBMV, genus Sobemovirus singly and in mixture (double and triple at 10, 20 and 30 days after planting (DAP. The treated plants were assessed for susceptibility to the viruses, growth and yield. In all cases of infection, early inoculation resulted in higher disease severity compared with late infection. The virus treated cowpea plants were relatively shorter than buffer inoculated control plants except the IT81D-985 plants that were taller and produced more foliage. Single infections by CABMV, CMeV and SBMV led to a complete loss of seeds in the three cowpea cultivars at 10DAP; only cultivar White produced some seeds at 30DAP. Double and triple virus infections led to a total loss of seeds in all three cowpea cultivars. None of the virus infected IITA lines produced any seeds except IT81D-985 plants co-infected with CABMV and SBMV at 30DAP with a reduction of 80%. Overall, the commercial cultivar White was the least susceptible to the virus treatments and produced the most yield (flowers, pods and seeds. CABMV was the most aggressive of these viruses and early single inoculations with this virus resulted in the premature death of some of the seedlings. The presence of the Potyvirus, CABMV in the double virus infections did not appear to increase disease severity or yield loss. There was no strong evidence for synergistic interactions between the viruses in the double virus mixtures.

Phosphate utilization by moong and cowpea under differential P fertility

International Nuclear Information System (INIS)

Thind, S.S.; Hundal, H.S.; Vig, A.C.

1993-01-01

A greenhouse experiment was conducted with 12 soils to study the effect of applied P on dry matter accumulation, P concentration, fertilizer and soil P uptake and utilization of P by moong and cowpea at two stages of growth. The magnitude of increase in yield due to applied P depended upon the native soil fertility. Low P fertility status soils registered proportionately higher increase in fertilizer P uptake. Dry matter yield of moong and cowpea significantly increased with increase in applied P in both the harvests, however in the first harvest (30 days growth stage) per cent increase with applied P over control was more in moong compared to cowpea. Soil P uptake increased significantly with applied P upto 60 kg P 2 O 5 /ha beyond which it decreased in both the harvests. The removal of P from applied and native sources was more in case of cowpea compared to moong. Per cent fertilizer P utilization in different soils varied from 45 to 11.9 in case of moong whereas its range in cowpea was 9.7 to 30.6 per cent. It decreased significantly with increase in applied P. (author). 7 refs., 1 fig., 3 tabs

Genome-wide association mapping and agronomic impact of cowpea root architecture.

Science.gov (United States)

Burridge, James D; Schneider, Hannah M; Huynh, Bao-Lam; Roberts, Philip A; Bucksch, Alexander; Lynch, Jonathan P

2017-02-01

Genetic analysis of data produced by novel root phenotyping tools was used to establish relationships between cowpea root traits and performance indicators as well between root traits and Striga tolerance. Selection and breeding for better root phenotypes can improve acquisition of soil resources and hence crop production in marginal environments. We hypothesized that biologically relevant variation is measurable in cowpea root architecture. This study implemented manual phenotyping (shovelomics) and automated image phenotyping (DIRT) on a 189-entry diversity panel of cowpea to reveal biologically important variation and genome regions affecting root architecture phenes. Significant variation in root phenes was found and relatively high heritabilities were detected for root traits assessed manually (0.4 for nodulation and 0.8 for number of larger laterals) as well as repeatability traits phenotyped via DIRT (0.5 for a measure of root width and 0.3 for a measure of root tips). Genome-wide association study identified 11 significant quantitative trait loci (QTL) from manually scored root architecture traits and 21 QTL from root architecture traits phenotyped by DIRT image analysis. Subsequent comparisons of results from this root study with other field studies revealed QTL co-localizations between root traits and performance indicators including seed weight per plant, pod number, and Striga (Striga gesnerioides) tolerance. The data suggest selection for root phenotypes could be employed by breeding programs to improve production in multiple constraint environments.

[Use of cowpea (Vigna sinensis) as a chicken complement in an infant formula].

Science.gov (United States)

Modernell, Marisa Guerra; Granito, Marisela; Paolini, Mariangel; Olaizola, Cristina

2008-09-01

Legumes represent an important protein source worldwide. In Venezuela, they are generally prepared at home and are consumed by adults, as soup or stew, while children eat them in very small quantities. In order to include legumes in the children's diet, the following work was done using cowpea (Vigna sinensis) as an complement of chicken in the preparation of a nutritionally balanced formula, adapted to the requirements of children. Several formulas were developed and three of them were selected based on their acceptability. In the first formula, the protein source was only of chicken. In the second formula, the chicken was partially substituted by cowpea, and in the third formula, the protein source was only made of cowpea. Other formula ingredients included rice, pumpkin (Curcubita maxima), carrot and some seasonings. Proximal analysis, protein quality (as protein efficiency ratio and protein digestibility) and sensory evaluation (7-point hedonic scale) were performed on the formulas. The proximal composition was similar in the three formulas: protein (3.5%), fat (1.3%) and carbohydrates (19.7%), with a good distribution of the energy contribution (98.9 kcal/100 g or 413.8 kJ/100 g). The protein quality and protein digestibility were higher for the chicken-cowpea formula than for the cowpea one. The acceptability with the mothers was higher for the chicken-cowpea formula than for the cowpea one. The acceptability of the chicken-cowpea formula with children was 77% (7-point hedonic facial scale) and 92% (measuring consumption). Due to the high acceptability and good protein quality, the chicken-cowpea formula could be included in the lunch meal of the children in daycare homes.

Current approaches to Alectra vogelii control in cowpea | Ngwako ...

African Journals Online (AJOL)

Alectra vogelii (L.) Benth is a parasitic weed in the family Scrophulariaceae that causes substantial damage by attaching onto the cowpea, Vigna unguiculata (L. Walp.) plant and tapping nutrients from it. Cowpea is one of the most important food legumes and is widely adapted to semi-arid environments in Africa. The crop is ...

Influence of COMT genotype and affective distractors on the processing of self-generated thought.

Science.gov (United States)

Kilford, Emma J; Dumontheil, Iroise; Wood, Nicholas W; Blakemore, Sarah-Jayne

2015-06-01

The catechol-O-methyltransferase (COMT) enzyme is a major determinant of prefrontal dopamine levels. The Val(158)Met polymorphism affects COMT enzymatic activity and has been associated with variation in executive function and affective processing. This study investigated the effect of COMT genotype on the flexible modulation of the balance between processing self-generated and processing stimulus-oriented information, in the presence or absence of affective distractors. Analyses included 124 healthy adult participants, who were also assessed on standard working memory (WM) tasks. Relative to Val carriers, Met homozygotes made fewer errors when selecting and manipulating self-generated thoughts. This effect was partly accounted for by an association between COMT genotype and visuospatial WM performance. We also observed a complex interaction between the influence of affective distractors, COMT genotype and sex on task accuracy: male, but not female, participants showed a sensitivity to the affective distractors that was dependent on COMT genotype. This was not accounted for by WM performance. This study provides novel evidence of the role of dopaminergic genetic variation on the ability to select and manipulate self-generated thoughts. The results also suggest sexually dimorphic effects of COMT genotype on the influence of affective distractors on executive function. © The Author (2014). Published by Oxford University Press.

Effects of high plant cowpeas ( Vigna unguculata ) and animal ...

African Journals Online (AJOL)

Serum bicarbonate values of baseline rats were significantly higher (P<0.01) in rats fed casein diet and cowpeas diets. However, urinary bicarbonate value of the casein fed rat was significantly higher (P<0.01) than that of baseline and cowpeas fed rats. This study has shown that the intake of high casein diet leads to an ...

Nutritional quality and utilization of local and improved cowpea ...

African Journals Online (AJOL)

Cowpeas are grown for their leaves and grains both of which are used as relish or side dishes together with the staple food. Little information is available on the nutritional quality of local and improved cowpea varieties grown in Tanzania as well as the recipes in which they are ingredients. This study was done to investigate ...

Efficacy of plant extracts against the cowpea beetle, Callosobruchus maculatus

NARCIS (Netherlands)

Boeke, S.J.; Barnaud, B.; Loon, van J.J.A.; Kossou, D.K.; Huis, van A.; Dicke, M.

2004-01-01

Traditionally used African plant powders, with a known effect against the cowpea beetle Callosobruchus maculatus in stored cowpea, were extracted with water. The extracts, 13 volatile oils, 2 non-volatile oils and 8 slurries, were evaluated for their toxic and repellent effects against the beetle.

Irradiation disinfestation of cowpea seeds to control southern cowpea beetle Callosbruchus maculatus (Fabricius) (Coleoptera Bruchidae)

International Nuclear Information System (INIS)

El-Kady, E.A.; Hekal, A.M.; El-Refai, S.

1987-01-01

The possibility of using gamma radiation as an alternative to fumigation or direct chemical applications for the control of stored-products insects was investigated in the laboratory and in a warehouse in Cairo, Egypt. Polyethylene bags of the type used in local markets were filled with cowpeas [Vigna unguiculata] Callosobruchus maculatus and irradiated at 400, 600 or 800 Gy [4, 6 or 8 krad]. All the treatments were effective, and no living adults infested by were found in the bags until 3 months later, when adults from outside penetrated the bags with their mandibles. It is therefore recommended that 4 krad should be administered for initial control, but that treated cowpeas should be stored in polypropylene rather than polyethylene bags in order to prevent reinfestation

Chickpea and cowpea grain improvement using mutation and other advanced genetic techniques

Energy Technology Data Exchange (ETDEWEB)

Filippone, E; Monti, L [Department of Agronomy and Plant Genetics, Univ. of Naples Federico 2, Naples (Italy)

1997-12-01

The use of genetic engineering methodologies in breeding programmes seems to be very promising to find new resistance-related genes present in other phyla, to clone and transfer them into plants; and, to shorten the time to obtain an improved genotype since only a single gene is involved in this process. The main ``bottle-neck`` to apply this scheme in chickpea and cowpea is the absence of a reliable protocol of regeneration and genetic transformation. In this frame, following some pilot experiments on these grain legumes to induce regeneration and gene transfer, we attempted to find a regeneration medium, assay the effect of different hormones on young tissues; and, to select the best procedures for transfer of genes into the plant genome.

Chickpea and cowpea grain improvement using mutation and other advanced genetic techniques

International Nuclear Information System (INIS)

Filippone, E.; Monti, L.

1997-01-01

The use of genetic engineering methodologies in breeding programmes seems to be very promising to find new resistance-related genes present in other phyla, to clone and transfer them into plants; and, to shorten the time to obtain an improved genotype since only a single gene is involved in this process. The main ''bottle-neck'' to apply this scheme in chickpea and cowpea is the absence of a reliable protocol of regeneration and genetic transformation. In this frame, following some pilot experiments on these grain legumes to induce regeneration and gene transfer, we attempted to find a regeneration medium, assay the effect of different hormones on young tissues; and, to select the best procedures for transfer of genes into the plant genome

A socio-economic assessment of cowpea diversity on the Ghanaian market: implications for breeding

NARCIS (Netherlands)

Quaye, W.; Adofo, K.; Buckman, E.S.; Frempong, G.; Jongerden, J.P.; Ruivenkamp, G.T.P.

2011-01-01

Given the importance of cowpea [Vignaunguiculata(L)Walp] in fighting malnutrition and poverty, a socio-economic assessment of cowpea diversity found on the Ghanaian market was conducted. The objective was to investigate emerging consumer preference for cowpea and make recommendations for the

The helper component-proteinase of cowpea aphid-borne mosaic virus

NARCIS (Netherlands)

Mlotshwa, S.

2000-01-01

Cowpea aphid-borne mosaic potyvirus causes severe yield losses in cowpea, an important legume crop in semi-arid regions of Africa. We have elucidated the genomic sequence of the virus and subsequently focused our attention on the so-called helper component-proteinase (HC-Pro), a

Genetic mapping and legume synteny of aphid resistance in African cowpea (Vigna unguiculata L. Walp.) grown in California.

Science.gov (United States)

Huynh, Bao-Lam; Ehlers, Jeffrey D; Ndeve, Arsenio; Wanamaker, Steve; Lucas, Mitchell R; Close, Timothy J; Roberts, Philip A

The cowpea aphid Aphis craccivora Koch (CPA) is a destructive insect pest of cowpea, a staple legume crop in Sub-Saharan Africa and other semiarid warm tropics and subtropics. In California, CPA causes damage on all local cultivars from early vegetative to pod development growth stages. Sources of CPA resistance are available in African cowpea germplasm. However, their utilization in breeding is limited by the lack of information on inheritance, genomic location and marker linkage associations of the resistance determinants. In the research reported here, a recombinant inbred line (RIL) population derived from a cross between a susceptible California blackeye cultivar (CB27) and a resistant African breeding line (IT97K-556-6) was genotyped with 1,536 SNP markers. The RILs and parents were phenotyped for CPA resistance using field-based screenings during two main crop seasons in a 'hotspot' location for this pest within the primary growing region of the Central Valley of California. One minor and one major quantitative trait locus (QTL) were consistently mapped on linkage groups 1 and 7, respectively, both with favorable alleles contributed from IT97K-556-6. The major QTL appeared dominant based on a validation test in a related F2 population. SNP markers flanking each QTL were positioned in physical contigs carrying genes involved in plant defense based on synteny with related legumes. These markers could be used to introgress resistance alleles from IT97K-556-6 into susceptible local blackeye varieties by backcrossing.

SWJ:39-42 Inheritance of Pod Colour in Cowpea INHERITANCE

African Journals Online (AJOL)

Dr. Ahmed

Mustapha & Singh (2008) SWJ:39-42. Inheritance of Pod Colour in Cowpea. INHERITANCE OF POD COLOUR IN. COWPEA (Vigna unguiculata (L.) WALP). * MUSTAPHA, Y1. & SINGH, B. B2. 1 Department of Biological Sciences. Bayero University, Kano Nigeria. 2 Department of Genetics and Plant breeding,. G.B. Pant ...

Isolation of protoplast from soybean, cowpea, and tobacco and their fusion

International Nuclear Information System (INIS)

Irwansyah.

1988-01-01

Protoplast were isolated from leaf and callus. Young leaf of 3-4 weeks old plant of soybean T219 and A24, A27, C4, E1, and H6 of cowpeas strains (strains named by Prof. S. Sakamoto, University of Kyoto) were suspended in digestive medium containing cellulase 'Onuzuka' R-10, macerozyme R-10, mannitol, CaCl, and 2 (N-morpholilno) echane sulfonic acid (MES). For soybean leaf, the medium was enriched with driselase and pectolyase Y-23. They were incibated in full darkness at 27 Celcius centigrade by constant shaking at 50 rpm orbitor shaker. Callus wich has been two times resubcultured was suspended in the digestive medium without driselase, CaCl2, and MES and incubated in lowlight intensity by constant shaking at 100 rpm in reciprocal water shaker at 30 celcius centigrade. Leaf protoplast were releasaed in 10-14 h, soybean and tobacco callus protoplast in 3-4 h, and cowpeas callus protoplast in 4-6 h of incubation. Protoplast were collected by centrifugation of 400 g and a thin layer of the suspension was irradiated with ultraviolet light. Fusion was induced with PEG 6000 solution according to Uchimia and fused protoplasts were collected by centrifugation of 200 g. Protoplast were cultured on the medium of Ikeda and Uchimia. On both medium leaf protoplast, irradiated protoplasts and their fused do not regenerate cell wall and all cultured died out within four weeks incubation. Cell wall generation was observed. Regeneration of cell wall observed progessively in mother protoplast from tobacco, cowpea (A27, E1, and H6) and fused protoplast of soybean with tobacco, tobacco with cowpea (C4, E1, and H6), soybean with cowpea (C4) and between cowpea (C4) and cowpea (E1). (author). 25 refs, 4 tabs

Identificação de Genótipos de Feijão-caupi Tolerantes a Acidez em um Latossolo Vermelho-Amarelo do Estado de Roraima = Identification of cowpea genotypes sensitivity to acidicy conditions in an Oxisol of Roraima State (Brazil.

Directory of Open Access Journals (Sweden)

Sandra Cátia Pereira Uchôa

2007-12-01

Full Text Available O presente trabalho foi realizado com o objetivo de identificar genótipos de feijão-caupi (Vigna unguiculata (L Walp., tolerantes à acidez. O trabalho foi realizado em casa de vegetação localizada no Campus do Cauamé, da Universidade Federal de Roraima, utilizando um Latossolo Vermelho-Amarelo de Boa Vista-RR. Foi adotado o delineamento experimental de Blocos Inteiramente Casualizados em esquema fatorial 2 x 5 x 10 com três repetições. Os tratamentos resultaram de duas formas de localização do calcário (localizada e não-localizada, 5 profundidades (0-5; 5-10; 10-15; 15-20; 20-25 cm e 10 genótipos de feijão-caupi(IT85D-3428-4-R2,4-HM; Apiaú; Hikari Graúdo; Pretinho Precoce 1; IT85D-3428-4-3-HP; USA; UFRR Grão Verde; BRS-Mazagão; Canapum e Sempre Verde. A unidade experimental foi constituída por 2dm3 de solo, dispostos em tubo de PVC com 25cm de altura,10cm de diâmetro e duas plantas de feijão. Os tubos foram confeccionados por meio da junção de 5 anéis com 5 cm cada, sendo que no anel inferior foi colocada uma placa delgada de isopor para permitir a acomodação do solo. Aos 40 dias após a emergência, as plantas foram coletadas, sendo determinada à produção de matéria seca das raízes e parte aérea. Os genótipos IT85D-3428-4-3-HP e UFRRGRÃO VERDE foram classificados como sendo de baixa tolerância, os genótipos USA, BRS-Mazagão, IT85D-3428-4-R2,4-HM e Sempre Verde, medianamente tolerantes e os genótipos Apiaú, Hikari Graúdo, Pretinho Precoce 1 e Canapum, tolerantes à acidez.= This research was carried out objecting to identify the sensibility of cowpea (Vigna unguiculata (L Walp genotypes to acidity conditions. The experiment was installed in a greenhouse located at Campus of Cauamé (Universidade Federal de Roraima in an oxisol of Roraima State (Brazil. The experimental design adopted was a completely andomized blocks in a factorial scheme 2 x 5 x 10 with three replicates. The terms of this factorial

Field evaluation of improved cowpea lines for resistance to bacterial ...

African Journals Online (AJOL)

STORAGESEVER

2008-10-20

Oct 20, 2008 ... The average productivity of cowpea in the existing traditional systems is low due to a complex of biotic and abiotic stresses. The biotic factors include insect pests, parasitic plants, and viral, fungal and bacterial diseases. Concerted efforts are being made to develop improved cowpea varieties with combined ...

Evaluation of ecophysiological characteristics of intercropping of millet (Panicum miliaceum L. and cowpea (Vigna unguiculata L.

Directory of Open Access Journals (Sweden)

A. Ghanbari

2016-04-01

Full Text Available In order to evaluate millet (Panicum miliaceum L. and cowpea (Vigna unguiculata L. intercropping, an experiment was conducted during 2008-2009 at Agriculture Research Center of Zabol University, Iran. The experiment was as randomized complete block design with three replications. Treatment s consisted of sole crop of millet, sole crop of cowpea, 25% millet + 100% cowpea, 50% millet + 50% cowpea, 75% millet + 100% cowpea and 100% millet + 100% cowpea. The results showed that intercropping treatments had significant effect (P < 1% on millet and bean seed yield, LER, dry matter of weeds, PAR, temperature and (P < 5% on soil moisture content. The highest seed yield of millet and cowpea obtained from treatments of sole crops. The LER for most intercrops was greater than one which indicated that intercropping had advantage over sole crop. For weeds management and control the results indicated that weed suppressing effects in intercropping treatments is better than sole crops treatment, so that the lowest dry matter of weeds obtained from 100% millet + 100% cowpea treatment. PAR in all of stages showed that the highest PAR interception obtained from intercropping treatments specially 100% millet + 100% cowpea treatment. In addition to the lowest of soil moisture content and temperature obtained from this treatment.

Identification of QTL controlling domestication-related traits in cowpea (Vigna unguiculata L. Walp).

Science.gov (United States)

Lo, Sassoum; Muñoz-Amatriaín, María; Boukar, Ousmane; Herniter, Ira; Cisse, Ndiaga; Guo, Yi-Ning; Roberts, Philip A; Xu, Shizhong; Fatokun, Christian; Close, Timothy J

2018-04-19

Cowpea (Vigna unguiculata L. Walp) is a warm-season legume with a genetically diverse gene-pool composed of wild and cultivated forms. Cowpea domestication involved considerable phenotypic changes from the wild progenitor, including reduction of pod shattering, increased organ size, and changes in flowering time. Little is known about the genetic basis underlying these changes. In this study, 215 recombinant inbred lines derived from a cross between a cultivated and a wild cowpea accession were used to evaluate nine domestication-related traits (pod shattering, peduncle length, flower color, days to flowering, 100-seed weight, pod length, leaf length, leaf width and seed number per pod). A high-density genetic map containing 17,739 single nucleotide polymorphisms was constructed and used to identify 16 quantitative trait loci (QTL) for these nine traits. Based on annotations of the cowpea reference genome, genes within these regions are reported. Four regions with clusters of QTL were identified, including one on chromosome 8 related to increased organ size. This study provides new knowledge of the genomic regions controlling domestication-related traits in cowpea as well as candidate genes underlying those QTL. This information can help to exploit wild relatives in cowpea breeding programs.

Cheese bread enriched with biofortified cowpea flour

Directory of Open Access Journals (Sweden)

Rodrigo Barbosa Monteiro Cavalcante

2016-02-01

Full Text Available ABSTRACT The development and enrichment of food are of great importance not only for the industry but also to improve the population's nutrition, where you can create new products or optimize existing ones. The consumption of fortified products in the diet is an option for the control of deficiency diseases. This study aimed to develop enriched cheese bread with whole biofortified cowpea flour and evaluate their acceptance and chemical composition. Two formulations, F1 and F2, were prepared containing 5.6 and 8% of cowpea flour as a substitute for starch, respectively. To check acceptance, three sensory tests were used (Hedonic Scale, Purchase Intent, and Paired Comparison, F1 being sensory viable according to assessors, being chemically analyzed. Minerals were determined by atomic emission spectrometry with inductively coupled plasma source. The moisture was determined by drying at 105 °C, ash by calcination in muffle at 550 °C, proteins by the macro-Kjeldahl method, and lipids by hot extraction in a Soxhlet extractor. Carbohydrates were obtained by difference and the calories were calculated. The addition of cowpea increased the amounts of copper, iron, phosphorus, magnesium, manganese, and zinc, as well as protein and carbohydrate values. On the other hand, there was a reduction of the moisture concerning lipids and the total caloric value compared to the standard formulation. It was concluded , therefore, that the cowpea, a regional raw material in market expansion is presented as an option for the enrichment of baked foods that do not contain gluten, such as cheese bread.

Cowpeas as growth substrate do not support the production of aflatoxinby Aspergillus sp

DEFF Research Database (Denmark)

Houssou, P.A.; Schnidt-Heydt, M.; Geisen, R.

2008-01-01

A number of 21 Aspergillus sp. strains isolated from cowpeas from Benin (Africa) were characterizedby RAPD methodology. Seven of these strains grouped with A. flavus in the dendrogram generated with the RAPD data. Only three were able to produce aflatoxin in significant amounts. Twelve other...... produced high amounts of aflatoxin after growth on YES medium. However after growth on cowpea based medium aflatoxin biosynthesis was strongly ceased, albeit the growth of the colony was only partly reduced. This was true for media made either with the whole cowpea seed or with cowpea seed without seed...... coat. Interestingly when the cowpea medium was heat sterilized the fungus was able to produce high amounts of aflatoxin. This, however, was not the case after the use of gamma irradiation as sterilization method for the medium. The expression of the nor-1 gene, which is one of the early genes involved...

Evaluation of the efficacy of Levo 2.4 Sl against the cowpea beetle, Callosobruchus maculatus (F.) on stored cowpea grains

International Nuclear Information System (INIS)

Osekre, E. A.; Abrahamani, J.; Abudu, D.T.

2013-01-01

The adverse effects of synthetic pesticides on the environment and non-target organisms have necessitated the exploration of other safer and equally effective pesticides for the management of pests. The efficacy of Levo 2.4 SL (Oxymatrine 2.4 SL; Prosular oxamatrine a. i.), a botanical, against Callosobruchus maculatus (F.) infestation on stored cowpea, Vigna unguiculata (L.) (Walp.) was investigated in the insectary of the Entomology Section of the Faculty of Agriculture of the Kwame Nkrumah University of Science and Technology. The effects of Levo on the adult mortality, ovipoistion and F1 progeny of the insect were evaluated. Thus 200 g of cowpea grains were treated with three dosages; 0.01 ml, 0.02 ml and 0.03 ml of Levo 2.4 SL. Betallic Supper 2.5 EC (Primophos methyl and Permethrin a. i.) was used as a check and a control (untreated grains) was also maintained. The mean number of eggs laid and the number of F1 adults that emerged were significantly (P < 0.05) smaller in the Levo treated grains than the control. The higher dosages of Levo 2.4 SL were more effective against C. maculatus infestation and damage. At the end of four months of storage, Levo at all the dosages offered complete protection to the cowpea grains. Levo 2.4 SL at a dosage of 0.02 ml is considered the right dosage that can give optimum protection to cowpea grains against C. maculatus. (au)

Protein and Iron composition of cowpea leaves: An evaluation of six ...

African Journals Online (AJOL)

Protein and Iron composition of cowpea leaves: An evaluation of six cowpea varieties grown in eastern Africa. ... African Journal of Food, Agriculture, Nutrition and Development ... Mineral element, protein-energy and micronutrient deficiencies are primary public health concerns in Eastern and Southern Africa. Promoting the ...

Effect Of Sprouting On Available Lysine Content Of Cowpea ( Vigna ...

African Journals Online (AJOL)

This study was conducted to determine the effect of sprouting on available Lysine content of cowpea (Vigna unguiculata) flour and the performance of the flour used for producing “moi – moi” (steamed bean cake). Cowpea seed was subjected to sprouting for different periods of 1 day, 2 days and 3 days for samples B, C and ...

Effectiveness of Arbuscular Mycorrhizal Fungal Isolates from the Land Uses of Amazon Region in Symbiosis with Cowpea.

Science.gov (United States)

Silva, Gláucia Alves E; Siqueira, José O; Stürmer, Sidney L; Moreira, Fatima M S

2018-01-01

Arbuscular mycorrhizal fungi provide several ecosystem services, including increase in plant growth and nutrition. The occurrence, richness, and structure of arbuscular mycorrhizal fungi communities are influenced by human activities, which may affect the functional benefits of these components of the soil biota. In this study, 13 arbuscular mycorrhizal fungi isolates originating from soils with different land uses in the Alto Solimões-Amazon region were evaluated regarding their effect on growth, nutrition, and cowpea yield in controlled conditions using two soils. Comparisons with reference isolates and a mixture of isolates were also performed. Fungal isolates exhibited a wide variability associated with colonization, sporulation, production of aboveground biomass, nitrogen and phosphorus uptake, and grain yield, indicating high functional diversity within and among fungal species. A generalized effect of isolates in promoting phosphorus uptake, increase in biomass, and cowpea yield was observed in both soils. The isolates of Glomus were the most efficient and are promising isolates for practical inoculation programs. No relationship was found between the origin of fungal isolate (i.e. land use) and their symbiotic performance in cowpea.

Use of Cowpea and Pigeon pea as Nutritional Ingredients in Culture ...

African Journals Online (AJOL)

Use of Cowpea and Pigeon pea as Nutritional Ingredients in Culture Media. ... Sudan Journal of Medical Sciences ... Cheap, locally available plant seeds such as cowpea (Vigna unguiculata) and pigeon pea (Cajanus cajan) could be used in the design and formulation of microbial culture media in order to reduce the cost.

Performance of cowpea (Vigna unguiculata) and pearl millet (Pennisetum glaucum) intercropped under Parkia biglobosa in an agroforestry system in Burkina Faso

DEFF Research Database (Denmark)

Osman, Ahmed Nur; Ræbild, Anders; Christiansen, Jørgen Lindskrog

2011-01-01

In agroforestry systems, crop yields under trees are often low compared to outside. This study explored crop management under trees for improved production and income for farmers. Cowpea (Vigna unguiculata) and pearl millet (Pennisetum glaucum) sole and intercrops were grown under and outside...... the trees and intercrops flowered earlier than sole crops. Cowpea sole crops had significant grain yield losses of up to 21% under trees compared to outside, and pearl millet yield was reduced up to 67% under trees. Intercrop yields were less affected by growth under trees. LER was significantly higher...... under the trees than outside, and were always larger than unity indicating benefits of intercropping over sole cropping. Intercropping with two rows of cowpea and one row of millet gave significantly higher economic benefit than mixture with one row of each of the crops. Results indicate...

Enhancing the digestibility of cowpea (Vigna unguiculata) by traditional processing and fermentation

NARCIS (Netherlands)

Madode, Y.E.; Nout, M.J.R.; Bakker, E.J.; Linnemann, A.R.; Hounhouigan, D.J.; Boekel, van M.A.J.S.

2013-01-01

Flatulence is an important drawback for the consumption of legumes. Therefore, the ability of traditional processing (dehulling, boiling, soaking) and fermentation (bacterial, fungal or yeast) of cowpeas to reduce flatulence was investigated. Raw and processed cowpeas were assessed for their

Comparative Effects of Cowpea and Soybean Genotypes on N2 ...

African Journals Online (AJOL)

acer

ABSTRACT:A field trial was conducted to asses N2 - fixation and N balance in five cultivars each of soybean (TGX 1945 – 1F, ... Key words: Legume genotype, N2 fixation, N balance and Nitrogen Harvest Index (NHI) ..... subsequent maize grain yield in the guinea savanna ... On-farm evaluation of biological nitrogen fixation.

GERMINATION AND INITIAL GROWTH OF COWPEA CULTIVARS UNDER OSMOTIC STRESS AND SALICYLIC ACID

OpenAIRE

ARAÚJO, EDILENE DANIEL DE; MELO, ALBERTO SOARES DE; ROCHA, MARIA DO SOCORRO; CARNEIRO, REBECA FERREIRA; ROCHA, MAURISRAEL DE MOURA

2018-01-01

ABSTRACT Cowpea is one of the major food crops in Northeast Brazil, where it is commonly cultivated in the semi-arid regions with limited water availability. It is important to study the elicitors associated with cowpea to mitigate any deleterious effects of abiotic stress on the initial establishment of this crop. In this study, we aimed to evaluate the morphophysiological changes in cowpea cultivars under osmotic stress with seeds soaked in salicylic acid. The germination test was conducted...

23 cowpea for a changing environment in the rainforest of south ...

African Journals Online (AJOL)

cowpea may be a desirable option for use in mitigating the effect of climate change in the context of shift in crops and animals that can ..... Table 4: Frequency distributions and selection scores for cowpea varieties. Selection attributes. Variety value. Selection score*. Number of varieties. Remarks. Biomass (kg ha-1). 876.0- ...

Phenotypic diversity and evaluation of fresh pods of cowpea landraces from Southern Europe.

Science.gov (United States)

Lazaridi, Efstathia; Ntatsi, Georgia; Fernández, Juan A; Karapanos, Ioannis; Carnide, Valdemar; Savvas, Dimitrios; Bebeli, Penelope J

2017-10-01

Cowpea fresh pods are consumed as green vegetables in many countries in Southern Europe. Among cowpea cultivated material, a relatively large number of landraces can be found, maintaining species genetic diversity. To assess the value of these landraces in breeding programs, the characterization and estimation of diversity levels is therefore required. In the present study, an estimation of the diversity and evaluation of cowpea landraces originating from Portugal, Spain and Greece, in terms of their fresh pod traits, was performed, aiming to assist with the problem of low cowpea production in Southern Europe. A notable mean total phenotypic diversity (H T = 0.57) was observed in the whole collection. The Spanish cv. - gr. unguiculata collection exhibited the highest value of total phenotypic diversity (0.56). Landraces did not differ significantly from each other regarding the three countries of origin. Landraces such as Cp4906, Vg60 and BGE038478 presenting higher values of some traits studied could contribute to the breeding of new cowpea varieties for fresh pod production. Positive correlations were observed, indicating the feasibility of breeding for preferable traits regarding fresh pod consumption. The present study has revealed a wide diversity among and within cowpea landraces that could enhance fresh pod production in South European countries. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Fertilizer Use and Management Practices among Maize and Cowpea Smallholder Farmer in Ghana

Directory of Open Access Journals (Sweden)

Okebalama, CB.

2016-01-01

Full Text Available In most parts of West Africa, poverty contributes immensely to poor fertilizer adoption by smallholder farmers. Fertilizer adoption could be improved with micro-dosing technology. A socio-economic survey was conducted in the semi-deciduous forest zone of Ghana to assess the extent of fertilizer use and management among maize and cowpea smallholder farmers. Oral interview with structured questionnaire was used to interview one hundred farmers each at two locations. The results showed that farmers are aware of the use of fertilizer to increase crop yield. About 65% and 80% of maize and cowpea farmers respectively, identified high cost of fertilizer as a major constraint to fertilizer utilization. Consequently, only 32% maize farmers and 19% cowpea farmers were fertilizer users. In addition, the choice of fertilizer type to use was dependent on the type available on the market. As such, NPK 15:15:15 was mostly used for both maize and cowpea crops. Also, fertilizer application rate was mainly determined by the quantity farmer can purchase. On average, fertilizer application rate for maize and cowpea crops were 18.45 kg/ha and 9.05 kg/ha, respectively. The prevalent fertilizer application method on maize was mostly by point/side placement while ring application was largely used for cowpea. Awareness of fertilizer micro-dosing among the farmers was only 10%. Since the quantity of fertilizer used by the farmers as well as the fertilizer application methods were comparable to fertilizer micro-dosing, dissemination of micro-dosing technology to these farmers could promote fertilizer use and management among smallholder farmers, and ultimately sustain maize and cowpea production.

CHROMIUM IN SOIL ORGANIC MATTER AND COWPEA AFTER FOUR CONSECUTIVE ANNUAL APPLICATIONS OF COMPOSTED TANNERY SLUDGE

Directory of Open Access Journals (Sweden)

Mara Lucia Jacinto Oliveira

2015-02-01

Full Text Available Tannery sludge contains high concentrations of inorganic elements, such as chromium (Cr, which may lead to environmental pollution and affect human health The behavior of Cr in organic matter fractions and in the growth of cowpea (Vigna unguiculata L. was studied in a sandy soil after four consecutive annual applications of composted tannery sludge (CTS. Over a four-year period, CTS was applied on permanent plots (2 × 5 m and incorporated in the soil (0-20 cm at the rates of 0, 2.5, 5.0, 10.0, and 20.0 Mg ha-1 (dry weight basis. These treatments were replicated four times in a randomized block design. In the fourth year, cowpea was planted and grown for 50 days, at which time we analyzed the Cr concentrations in the soil, in the fulvic acid, humic acid, and humin fractions, and in the leaves, pods, and grains of cowpea. Composted tannery sludge led to an increase in Cr concentration in the soil. Among the humic substances, the highest Cr concentration was found in humin. The application rates of CTS significantly increased Cr concentration in leaves and grains.

Field trials with plant products to protect stored cowpea against insect damage

NARCIS (Netherlands)

Boeke, S.J.; Kossou, D.K.; Huis, van A.; Loon, van J.J.A.; Dicke, M.

2004-01-01

Plant products were evaluated under field conditions for their efficacy as insecticides against the cowpea beetle, Callosobruchus maculatus, on stored cowpea. Seeds, mixed with finely ground clay and three volatile oils were stored in air-tight jerry-cans and canisters. Pods were treated with leaf

Association mapping of aphid resistance in USDA cowpea (Vigna unguiculata L. Walp.) core collection using SNPs

Science.gov (United States)

Cowpea aphid (CPA; Aphis craccivora) is a destructive insect pest of cowpea, as well as other legume crops including alfalfa, beans, chickpea, lentils, lupins and peanuts. The utilization of aphid resistance in cowpea breeding is one of the most efficient and environmental friendly methods to contro...

Cowpeas in Northern Ghana and the Factors that Predict Caregivers’ Intention to Give Them to Schoolchildren

NARCIS (Netherlands)

Abizari, A.R.; Pilime, N.; Armar-Klemesu, M.; Brouwer, I.D.

2013-01-01

Background Cowpeas are important staple legumes among the rural poor in northern Ghana. Our objectives were to assess the iron and zinc content of cowpea landraces and identify factors that predict the intention of mothers/caregivers to give cowpeas to their schoolchildren. Methods and Findings We

De novo transcriptomic analysis of cowpea (Vigna unguiculata L. Walp.) for genic SSR marker development.

Science.gov (United States)

Chen, Honglin; Wang, Lixia; Liu, Xiaoyan; Hu, Liangliang; Wang, Suhua; Cheng, Xuzhen

2017-07-11

Cowpea [Vigna unguiculata (L.) Walp.] is one of the most important legumes in tropical and semi-arid regions. However, there is relatively little genomic information available for genetic research on and breeding of cowpea. The objectives of this study were to analyse the cowpea transcriptome and develop genic molecular markers for future genetic studies of this genus. Approximately 54 million high-quality cDNA sequence reads were obtained from cowpea based on Illumina paired-end sequencing technology and were de novo assembled to generate 47,899 unigenes with an N50 length of 1534 bp. Sequence similarity analysis revealed 36,289 unigenes (75.8%) with significant similarity to known proteins in the non-redundant (Nr) protein database, 23,471 unigenes (49.0%) with BLAST hits in the Swiss-Prot database, and 20,654 unigenes (43.1%) with high similarity in the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Further analysis identified 5560 simple sequence repeats (SSRs) as potential genic molecular markers. Validating a random set of 500 SSR markers yielded 54 polymorphic markers among 32 cowpea accessions. This transcriptomic analysis of cowpea provided a valuable set of genomic data for characterizing genes with important agronomic traits in Vigna unguiculata and a new set of genic SSR markers for further genetic studies and breeding in cowpea and related Vigna species.

Plant genotypes affect aboveground and belowground herbivore interactions by changing chemical defense.

Science.gov (United States)

Li, Xiaoqiong; Guo, Wenfeng; Siemann, Evan; Wen, Yuanguang; Huang, Wei; Ding, Jianqing

2016-12-01

Spatially separated aboveground (AG) and belowground (BG) herbivores are closely linked through shared host plants, and both patterns of AG-BG interactions and plant responses may vary among plant genotypes. We subjected invasive (USA) and native (China) genotypes of tallow tree (Triadica sebifera) to herbivory by the AG specialist leaf-rolling weevil Heterapoderopsis bicallosicollis and/or the root-feeding larvae of flea beetle Bikasha collaris. We measured leaf damage and leaves rolled by weevils, quantified beetle survival, and analyzed flavonoid and tannin concentrations in leaves and roots. AG and BG herbivores formed negative feedbacks on both native and invasive genotypes. Leaf damage by weevils and the number of beetle larvae emerging as adults were higher on invasive genotypes. Beetles reduced weevil damage and weevils reduced beetle larval emergence more strongly for invasive genotypes. Invasive genotypes had lower leaf and root tannins than native genotypes. BG beetles decreased leaf tannins of native genotypes but increased root tannins of invasive genotypes. AG herbivory increased root flavonoids of invasive genotypes while BG herbivory decreased leaf flavonoids. Invasive genotypes had lower AG and BG herbivore resistance, and negative AG-BG herbivore feedbacks were much stronger for invasive genotypes. Lower tannin concentrations explained overall better AG and BG herbivore performances on invasive genotypes. However, changes in tannins and flavonoids affected AG and BG herbivores differently. These results suggest that divergent selection on chemical production in invasive plants may be critical in regulating herbivore performances and novel AG and BG herbivore communities in new environments.

COMPARATIVE GERMINATION RESPONSES OF COWPEA AND ...

African Journals Online (AJOL)

iya beji

inadequate soil moisture (25%) in both cowpea and maize with greater effect on ... Of all factors controlling productivity, seed germination and vigour are pre- .... depth and date of first irrigation on seed cane germination of two commercial.

(ajst) influence of fermentation and cowpea

African Journals Online (AJOL)

opiyo

Statgraphics (Graphics Software System, STCC, Inc. U.S.A). Comparisons .... 7 2. 0.473. 0.597. 1.056. 0.14. Co-fermentation. Fermented maize and cowpea blends showed varied effects ...... Oligosaccharides in eleven Legumes and their air-.

Distribution and Prevalence of Parasitic Nematodes of Cowpea (Vigna unguiculata) in Burkina Faso.

Science.gov (United States)

Sawadogo, A; Thio, B; Kiemde, S; Drabo, I; Dabire, C; Ouedraogo, J; Mullens, T R; Ehlers, J D; Roberts, P A

2009-06-01

A comprehensive survey of the plant parasitic nematodes associated with cowpea (Vigna unguiculata) production fields was carried out in the three primary agro-climatic zones of Burkina Faso in West Africa. Across the three zones, a total of 109 samples were collected from the farms of 32 villages to provide a representative coverage of the cowpea production areas. Samples of rhizosphere soil and samples of roots from actively growing cowpea plants were collected during mid- to late-season. Twelve plant-parasitic nematode genera were identified, of which six appeared to have significant parasitic potential on cowpea based on their frequency and abundance. These included Helicotylenchus, Meloidogyne, Pratylenchus, Scutellonema, Telotylenchus, and Tylenchorhynchus. Criconemella and Rotylenchulus also had significant levels of abundance and frequency, respectively. Of the primary genera, Meloidogyne, Pratylenchus, and Scutellonema contained species which are known or suspected to cause losses of cowpea yield in other parts of the world. According to the prevalence and distribution of these genera in Burkina Faso, their potential for damage to cowpea increased from the dry Sahelian semi-desert zone in the north (annual rainfall < 600 mm/year), through the north-central Soudanian zone (annual rainfall of 600-800 mm/year), to the wet Soudanian zone (annual rainfall ≥ 1000 mm) in the more humid south-western region of the country. This distribution trend was particularly apparent for the endoparasitic nematode Meloidogyne and the migratory endoparasite Pratylenchus.

Influence of Gamma Irradiation, Soaking and Cooking the Detoxification of Aflatoxin β1 and sensory characteristics of Cowpea

International Nuclear Information System (INIS)

Mahrous, S.R.

2004-01-01

The present work deals with the effect of gamma irradiation, soaking in water and cooking on reducing or removal of aflatoxin β 1 as well as on sensory characteristics of cow peas. Long-time soaking (12 h) of gamma irradiated (5-10 kGy) Cowpea caused remarkable reduction in the levels of aflatoxin β 1 by about 88.4 to 97.28% . Cooking under pressure of gamma irradiated cowpea was more effective in detoxifying aflatoxin β 1 than ordinary cooking under pressure of 6 hours pre-soaked 7.5 kGy irradiated cowpea detoxified aflatoxin β 1 by 95.92% and there was no aflatoxin β 1 in 10 kGy irradiated cowpea. The sensory evaluation of pre-soaked and cooking under pressure of 10 kGy irradiated cowpea improved the overall acceptability of cowpea. In general, gamma irradiation, soaking and cooking (ordinary or under pressure) detoxified aflatoxin β 1 and did not induce any significant effect on the sensory profile in the cowpea

Functional properties of plantain, cowpea flours and oat fiber in extruded products

Science.gov (United States)

Drying effect on functional properties of two plantain and cowpea varieties and suitability of their flour blends in extruded snacks was determined. The functional and rheological behaviors of (plantain: cowpea): 90:10, 80:20, 70:30, 60:40 and 50:50 blends were evaluated. The extrusion product melt ...

Effect of gamma irradiation and cooking on cowpea bean grains (Vigna unguiculata L. Walp)

Energy Technology Data Exchange (ETDEWEB)

Santos Cople Lima, Keila dos, E-mail: keila@ime.eb.br [Nuclear Engineering Department, Military Institute of Engineering, Rio de Janeiro/RJ, Praca General Tiburcio, 80, CEP 22290-270 Rio de Janeiro/RJ (Brazil); Boher e Souza, Luciana [Nuclear Engineering Department, Military Institute of Engineering, Rio de Janeiro/RJ, Praca General Tiburcio, 80, CEP 22290-270 Rio de Janeiro/RJ (Brazil); Oliveira Godoy, Ronoel Luiz de [Technological Center, Embrapa Food Agroindustry, Av. das Americas, 29501, CEP 23020-470 Rio de Janeiro/RJ (Brazil); Costa Franca, Tanos Celmar; Santos Lima, Antonio Luis dos [Chemical Engineering Department, Military Institute of Engineering, Praca General Tiburcio, 80, CEP 22290-270 Rio de Janeiro/RJ (Brazil)

2011-09-15

Leguminous plants are important sources of proteins, vitamins, carbohydrates, fibers and minerals. However, some of their non-nutritive elements can present undesirable side effects like flatulence provoked by the anaerobic fermentation of oligosaccharides, such as raffinose and stachyose, in the gut. A way to avoid this inconvenience, without any change in the nutritional value and post-harvesting losses, is an irradiation process. Here, we evaluated the effects of gamma irradiation on the amino acids, thiamine and oligosaccharide contents and on the fungi and their toxin percentages in cowpea bean (Vigna unguiculata L. Walp) samples. For irradiation doses of 0.0, 0.5, 1.0, 2.5, 5.0 and 10.0 kGy the results showed no significant differences in content for the uncooked samples. However, the combination of irradiation and cooking processes reduced the non-nutritive factors responsible for flatulence. Irradiation also significantly reduced the presence of Aspergillus, Penicilium, Rhizopus and Fusarium fungi and was shown to be efficient in grain conservation for a storage time of 6 months. - Highlights: > In this study we evaluated cowpea beans subjected to different doses of gamma irradiation > Cowpea bean grains represent an important source of vegetal protein for Brazilian population. > Non-nutritive factors were reduced by irradiation and cooking. > Several genera of fungus were reduced by irradiation without affecting the nutritional content. > Irradiation helps the cooking process preserving thermosensible nutrients.

On the involvement of host proteins in Cowpea mosaic virus intercellular spread

NARCIS (Netherlands)

Hollander, den P.W.

2014-01-01

Abstract of thesis Paulus den Hollander entitled “On the involvement of host proteins in Cowpea mosaic virus intercellular spread”.

Defence: 18th of November 13.30 h

Abstract

Intercellular spread of Cowpea mosaic virus (CPMV) occurs via movement

Socio-cultural factors influencing and maintaining yam and cowpea diversity in Benin

NARCIS (Netherlands)

Zannou, A.; Tossou, R.C.; Vodouhè, S.; Richards, P.; Struik, P.C.; Zoundjihékpon, J.; Ahanchédé, A.; Agbo, V.

2007-01-01

Yam and cowpea are important elements in the food culture of local communities in the Transitional Guinea-Sudan Zone of Benin. Yam and cowpea serve to satisfy vital needs in households and in communities, but also play an essential role in the rituals and ceremonies of the agrarian civilizations of

Genomics Data for Cowpea Pests in Africa

Data.gov (United States)

US Agency for International Development — This dataset contains the complete mitochondrial genome of Anoplocnemis curvipes F. (Coreinea, Coreidae, Heteroptera), a pest of fresh cowpea pods. To get to the...

Proanthocyanidin profile of cowpea (Vigna unguiculata) reveals catechin-O-glucoside as the dominant compound.

Science.gov (United States)

Ojwang, Leonnard O; Yang, Liyi; Dykes, Linda; Awika, Joseph

2013-08-15

Proanthocyanidin (PA) profile and content can have important nutritional and health implications on plant foods. Six diverse cowpea phenotypes (black, red, green, white, light-brown and golden-brown) were investigated for PA composition using normal-phase HPLC and reversed-phase UPLC-TQD-MS. Catechin and (epi)afzelechin were the major flavan-3-ol units. Unusual composition was observed in all cowpea phenotypes with significant degrees of glycosylation in the monomers and dimers. The PA content of cowpea (dry basis) ranged between 2.2 and 6.3 mg/g. Monomeric flavan-3-ols were the largest group of PA (36-69%) in cowpea, with catechin-7-O-glucoside accounting for most (about 88%) of the monomers. The oligomers with degree of polymerization (DP) 2-4 ranged from 0.41 to 1.3 mg/g (15-20%), whereas DP>10 polymers accounted for only 13.5% of PA. Future studies that highlight the impact of the unusual cowpea PA profile on nutritional and bioactive properties of this important legume are warranted. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effect of oil palm sludge on cowpea nodulation and weed control in ...

African Journals Online (AJOL)

A field trial was conducted at the Rivers State University of Science and Technology Research and Training farm Port Harcourt to test the effect of oil palm sludge on cowpea nodulation and weed control. The cultivars of cowpea used were Dan Kano, Bornu local and Sokoto local while the oil palm sludge levels applied ...

Effects of cowpea fortification and the level of ripeness of plantain on ...

African Journals Online (AJOL)

Effects of cowpea fortification and the level of ripeness of plantain on the nutritive value of plantain based snack foods. ... The proximate composition and acceptability of products using a 7-point hedonic scale were evaluated. With the addition of 30% cowpea, the protein content of the Kaklo from the firm ripe and soft ripe ...

Utilization of graded levels of corn cobs and cowpea husk on growth ...

African Journals Online (AJOL)

Corncob (CC) and cowpea husk (CH) are by – products of maize and cowpea production respectively. They can be used as alternative feed resources for ruminants especially during the dry season. A 70d study was conducted to determine the effects of CC and CH based diets on performance of WAD rams. Sixteen ewes ...

Land use and vegetation cover on native symbionts and interactions with cowpea

Directory of Open Access Journals (Sweden)

Beatriz C. F. Rocha

Full Text Available ABSTRACT Arbuscular mycorrhizal fungi and rhizobia are important components of agroecosystems and they respond to human interference. The objective of this study was to investigate native communities of those microorganisms in soil collected under the native forest, four pastures (Brachiaria brizantha, Panicum maximum, Arachis pintoi and Stylosanthes guianensis and a fallow soil after maize cultivation, in interaction with cowpea (Vigna unguculata. The cowpea grew in a greenhouse until flowering. They were randomly distributed depending on soil, in five replications. The lowest mycorrhizal fungi sporulation and mycorrhizal root colonization occurred under the Panicum and forest soil. In the soils under forest and Stylosanthes, the cowpea did not exhibit nodules and grew less. Among the anthropized areas, the effect was variable, with stimulus to the multiplication and symbiosis of these microorganisms, except in areas of Panicum and Stylosanthes. When the native vegetation is substituted by pasture or farming, the mycorrhizal fungi and rhizobia proliferation predominate. However, the effect and its magnitude depends on the grown plant species, with reflects on the plant species in succession, such as the cowpea.

Additive interactions of unrelated viruses in mixed infections of cowpea (Vigna unguiculata L. Walp).

Science.gov (United States)

Nsa, Imade Y; Kareem, Kehinde T

2015-01-01

This study was carried out to determine the effects of single infections and co-infections of three unrelated viruses on three cowpea cultivars (one commercial cowpea cultivar "White" and 2 IITA lines; IT81D-985 and TVu 76). The plants were inoculated with Cowpea aphid-borne mosaic virus (CABMV), genus Potyvirus, Cowpea mottle virus (CMeV), genus Carmovirus and Southern bean mosaic virus (SBMV), genus Sobemovirus singly and in mixture (double and triple) at 10, 20, and 30 days after planting (DAP). The treated plants were assessed for susceptibility to the viruses, growth, and yield. In all cases of infection, early inoculation resulted in higher disease severity compared with late infection. The virus treated cowpea plants were relatively shorter than buffer inoculated control plants except the IT81D-985 plants that were taller and produced more foliage. Single infections by CABMV, CMeV, and SBMV led to a complete loss of seeds in the three cowpea cultivars at 10 DAP; only cultivar White produced some seeds at 30 DAP. Double and triple virus infections led to a total loss of seeds in all three cowpea cultivars. None of the virus infected IITA lines produced any seeds except IT81D-985 plants co-infected with CABMV and SBMV at 30 DAP with a reduction of 80%. Overall, the commercial cultivar "White" was the least susceptible to the virus treatments and produced the most yield (flowers, pods, and seeds). CABMV was the most aggressive of these viruses and early single inoculations with this virus resulted in the premature death of some of the seedlings. The presence of the Potyvirus, CABMV in the double virus infections did not appear to increase disease severity or yield loss. There was no strong evidence for synergistic interactions between the viruses in the double virus mixtures.

Insect pests associated with cowpea – sorghum intercropping system by considering the phenological stages

Directory of Open Access Journals (Sweden)

Diana González Aguiar

2016-10-01

Full Text Available The research aims to determine the main insect pest populations and their behavior in the combination cowpea - sorghum. This work took into account the phenology of each crop. The study was conducted on a Cambisol soil from the Basic Unit of Cooperative Production “Día y Noche”, which belongs to the Basic Unit of Cooperative Production “28 de Octubre”, Santa Clara municipality, Villa Clara province, Cuba. The experimental design was a random blocks included four treatments and four repetitions. The first arrangement consisted of two rows of cowpea for each row of sorghum; the second one included three rows of cowpea and one row of sorghum. The other treatments were the monocultures of cowpea and sorghum. The methodology included visual observations of plants with a weekly frequency until crop harvest to detect the presence of the insects. Also, the phenology of each crop was considered. The phytophagous insects quantified in the cowpea crop belong to the families Chrysomelidae, Pyralidae, Cicadellidae, while in the sorghum crop, these insects belong to the families Noctuidae and Aphididae. Finally, the results showed the positive effects of both spatial arrangements with a smaller incidence of insect pest populations.

Genetic and physical mapping of candidate genes for resistance to Fusarium oxysporum f.sp. tracheiphilum race 3 in cowpea [Vigna unguiculata (L.) Walp].

Science.gov (United States)

Pottorff, Marti; Wanamaker, Steve; Ma, Yaqin Q; Ehlers, Jeffrey D; Roberts, Philip A; Close, Timothy J

2012-01-01

Fusarium oxysporum f.sp. tracheiphilum (Fot) is a soil-borne fungal pathogen that causes vascular wilt disease in cowpea. Fot race 3 is one of the major pathogens affecting cowpea production in California. Identification of Fot race 3 resistance determinants will expedite delivery of improved cultivars by replacing time-consuming phenotypic screening with selection based on perfect markers, thereby generating successful cultivars in a shorter time period. Resistance to Fot race 3 was studied in the RIL population California Blackeye 27 (resistant) x 24-125B-1 (susceptible). Biparental mapping identified a Fot race 3 resistance locus, Fot3-1, which spanned 3.56 cM on linkage group one of the CB27 x 24-125B-1 genetic map. A marker-trait association narrowed the resistance locus to a 1.2 cM region and identified SNP marker 1_1107 as co-segregating with Fot3-1 resistance. Macro and microsynteny was observed for the Fot3-1 locus region in Glycine max where six disease resistance genes were observed in the two syntenic regions of soybean chromosomes 9 and 15. Fot3-1 was identified on the cowpea physical map on BAC clone CH093L18, spanning approximately 208,868 bp on BAC contig250. The Fot3-1 locus was narrowed to 0.5 cM distance on the cowpea genetic map linkage group 6, flanked by SNP markers 1_0860 and 1_1107. BAC clone CH093L18 was sequenced and four cowpea sequences with similarity to leucine-rich repeat serine/threonine protein kinases were identified and are cowpea candidate genes for the Fot3-1 locus. This study has shown how readily candidate genes can be identified for simply inherited agronomic traits when appropriate genetic stocks and integrated genomic resources are available. High co-linearity between cowpea and soybean genomes illustrated that utilizing synteny can transfer knowledge from a reference legume to legumes with less complete genomic resources. Identification of Fot race 3 resistance genes will enable transfer into high yielding cowpea varieties

Molecular detection, distribution and Pathogenesis of cowpea ...

African Journals Online (AJOL)

user

2012-09-25

Sep 25, 2012 ... In addition, fresh leaf and mature seed samples (100 per field) were collected ... protocol. Seed samples were processed as described by Koenraadt and ..... of farmer perception on pesticide usage for management of cowpea.

Effects of effluent water on the abundance of cowpea insect pests.

Science.gov (United States)

Tiroesele, Bamphitlhi; Sitwane, Monametsi; Obopile, M; Ullah, Muhammad Irfan; Ali, Sajjad

2017-10-03

Botswana experiences low and unreliable rainfall. Thus, the use of effluent water in agriculture is increasingly important. Insect damage is the major constraint for cowpea grain production in the most cowpea-producing lands. We investigated the effects of effluent water on insect pest abundance on cowpea (Vigna unguiculata) under field conditions. The experiment was laid out in a randomized complete block design with 100, 75, 50, and 25% of effluent water and 0% (control-clean tap water) treatments. Treatments with 100% effluent water resulted in a significant increase in insect pest populations as compared with the control. These results show that the use of effluent water to irrigate crops may increase incidence, abundance, and damage caused by insect pests possibly by decreasing plant vigor. The use of effluent water in agriculture should be addressed in a wise way.

Modelling farmers’ decisions on adoption and intensification of improved cowpea seeds in Niger

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O.H. Issoufou

2018-01-01

Full Text Available In Niger, global change leads farmers increasingly to intensify their agricultural production. That is one of the reason improved seeds have been diffused among farmers since decades. The study uses Logit and Tobit software for modeling farmers’ decision on adoption and intensification of improved cowpea seeds. The sample consisted of 612 agricultural households selected by random sampling without replacement in 16 villages. Data was collected in 2015 to 2016 through individual survey and focus group. The results show that the rate of improved cowpea seed adoption is 39.7% after three years of introduction. The accessibility of village, age and availability, accessibility of seeds determine at the same time decisions of adoption and intensification of improved cowpea seeds. The probability of improved seeds adoption is determined by education, access to agricultural extension and adaptability, productivity of seeds. Crops Risk perception and preference, precocity of seeds only affect the intensification probability. The analysis of marginal effects shows that adoption probability increases for accessibility of village, education, access to agricultural extension and adaptability, availability and productivity of improved seeds. On the other hand, the probability decreases for age and the availability of seed. Looking at also the marginal effects on seed intensification, it was observed that the probability increases for accessibility of village, perception of production risk and preference, availability and precocity of improved seeds. However, this probability decreases for age and seeds accessibility. These determinants of adoption and intensification are essential for improved seeds dissemination action to enhance the rate of adoption, intensity of seeds use, impact and sustainability for producers.

Overcoming barriers to trust in agricultural biotechnology projects: a case study of Bt cowpea in Nigeria

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Ezezika Obidimma C

2012-11-01

Full Text Available Abstract Background Nigeria, Africa’s most populous country, has been the world’s largest cowpea importer since 2004. The country is currently in the early phases of confined field trials for two genetically modified crops: Bacillus thuringiensis (Bt cowpea and nutritionally enhanced cassava (“BioCassava Plus”. Using the bio-safety guidelines process as a backdrop, we evaluate the role of trust in the operation of the Cowpea Productivity Improvement Project, which is an international agricultural biotechnology public-private partnership (PPP aimed at providing pest-resistant cowpea varieties to Nigerian farmers. Methods We reviewed the published literature and collected data through direct observations and semi-structured, face-to-face interviews. Data were analyzed based on emergent themes to create a comprehensive narrative on how trust is understood and built among the partners and with the community. Results Our findings highlight the importance of respecting mandates and eliminating conflicts of interest; holding community engagement initiatives early on; having on-going internal discussion and planning; and serving a locally-defined need. These four lessons could prove helpful to other agricultural biotechnology initiatives in which partners may face similar trust-related challenges. Conclusions Overcoming challenges to building trust requires concerted effort throughout all stages of project implementation. Currently, plans are being made to backcross the cowpea strain into a local variety in Nigeria. The development and adoption of the Bt cowpea seed hinges on the adoption of a National Biosafety Law in Nigeria. For countries that have decided to adopt biotech crops, the Nigerian cowpea experiment can be used as a model for other West African nations, and is actually applied as such in Ghana and Burkina Faso, interested in developing a Bt cowpea.

Seed coat darkening in Cowpea bean

Science.gov (United States)

Seed coat of cowpea bean (Vigna unguiculata L. Walp) slowly browns to a darker color during storage. High temperature and humidity during storage might contribute to this color change. Variation in browning rate among seeds in a lot leads to a mixture of seed colors creating an unacceptable product...

Genotypic differences in yield formation, phosphorus utilization and nitrogen fixation by cowpeas in Sierra Leone

International Nuclear Information System (INIS)

Amara, D.S.

1996-01-01

Available phosphorus (P) and nitrogen (NP) generally occur in very low amounts in soils of the tropics and subtropics. Under such conditions, most crops would require the addition of N and P fertilizer. This is not possible for small-scale farmers who cannot afford or have limited access to fertilizers, and therefore depend on low-input cropping systems. The selection of cultivars adapted to low soil nutrient conditions would sustain the production levels of subsistence farmers. Experiments were therefore conducted over a five-year period to identify cowpea cultivars with high phosphorus use efficiency and nitrogen fixation. Two of such cultivars-IT86D-1010 and IT86D-719 have been identified. Root morphological characteristics such as root length, root fineness and vesicular-arbuscular mycorrhizae are responsible for high P uptake and use efficiency. Multilocational testing of the cultivars showed that they cannot do well in areas with low rainfall. They have been distributed to farmers through the extension services for large scale production in southern Sierra Leone. (author). 28 refs, 4 figs, 6 tabs

Genotypic differences in yield formation, phosphorus utilization and nitrogen fixation by cowpeas in Sierra Leone

Energy Technology Data Exchange (ETDEWEB)

Amara, D S [Sierra Leone Univ., Njala Univ. College, Freetown (Sierra Leone). Dept. of Soil Science; Suale, D S [Institute of Agricultural Research, Freetown (Sierra Leone)

1996-07-01

Available phosphorus (P) and nitrogen (NP) generally occur in very low amounts in soils of the tropics and subtropics. Under such conditions, most crops would require the addition of N and P fertilizer. This is not possible for small-scale farmers who cannot afford or have limited access to fertilizers, and therefore depend on low-input cropping systems. The selection of cultivars adapted to low soil nutrient conditions would sustain the production levels of subsistence farmers. Experiments were therefore conducted over a five-year period to identify cowpea cultivars with high phosphorus use efficiency and nitrogen fixation. Two of such cultivars-IT86D-1010 and IT86D-719 have been identified. Root morphological characteristics such as root length, root fineness and vesicular-arbuscular mycorrhizae are responsible for high P uptake and use efficiency. Multilocational testing of the cultivars showed that they cannot do well in areas with low rainfall. They have been distributed to farmers through the extension services for large scale production in southern Sierra Leone. (author). 28 refs, 4 figs, 6 tabs.

SELECTIVITY OF DIFFERENT HERBICIDES TO COWPEA

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Francisco Aires Sizenando Filho2

2013-12-01

1.5 = recommended rate + half the recommended rate. At the end of the experiment it was found that: the cowpea showed phytotoxicity to use herbicide among 14 and 21 AAD; the herbicides diuron and metolachlor showed a rate "middle" in control weed, while the pendimethalin wasn't efficient for those function.

Phenolic composition and antioxidant properties of koose, a deep-fat fried cowpea cake.

Science.gov (United States)

Apea-Bah, Franklin B; Serem, June C; Bester, Megan J; Duodu, Kwaku G

2017-12-15

Koose, a West African delicacy, is a side dish prepared by deep frying thick cowpea paste. The current research determined the effect of deep-fat frying of cowpea paste on its total phenolic content (TPC), phenolic composition and antioxidant properties. Four cowpea cultivars comprising two reddish-brown, a brownish-cream and cream phenotypes were used. Liquid chromatography-mass spectrometry was used to determine phenolic composition of the samples. TPC was determined using Folin-Ciocalteu method while radical scavenging capacities were by Trolox equivalent antioxidant capacity, oxygen radical absorbance capacity and nitric oxide scavenging assays. The phenolic acids identified included benzoic and cinnamic acid derivatives. The predominant flavonoid classes were flavan-3-ols and flavonols. Deep-fat frying of the cowpea pastes decreased their TPC, radical scavenging capacities and total quantified flavonoids. The koose inhibited radical-induced oxidative cellular and DNA damage. It is concluded that koose is a potential functional food that can contribute to alleviating radical-induced oxidative stress. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of Tillage on Yield and Economic Returns of Maize and Cowpea in Semi-Arid Eastern Kenya

International Nuclear Information System (INIS)

Miriti, M.J; Kironchi, G; Gachene, K.K.C; Esilaba, O.A.; Mwangi, M.D; Nyamwaro, S.O; Heng, K.L

2014-01-01

Crop yields and financial returns are important criteria for adoption of conservation tillage by farmers. A study was conducted between 2007-2010 to compare the financial returns of subsoiling-ripping and tied-ridge tillage with the conventional ox-plough tillage in the production of maize (Zea mays L.) and cowpea (Vigna unguiculata L.) under semi-arid subsistence farming conditions in lower eastern Kenya. Four cropping systems namely maize sole crop, cowpea sole crop, maize/cowpea intercrop and maize sole crop with manure were evaluated in a split-plot treatments arrangement with tillage practices as the main plots and cropping systems as the sub-plots. The grain yields of maize and cowpea, prevailing market prices for cowpea and maize grains, labour, inputs applied and other relevant socio-economic data were collected every season, to enable estimation of economic returns and acceptability of the technologies. The results showed that average grain yield for maize sole crop, cowpea sole crop, maize/cowpea intercrop and maize sole crop with manure cropping systems under tied-ridge were 5, 9, 97 and 27% greater than the yields under oxplough tillage, respectively. Crop yields produced under subsoiling-ripping and ox-plough tillage were generally similar. However, land preparation and weeding labour expenses (KES 4240 / ha) for ox-plough tillage were 34% greater than those for subsoiling-ripping tillage but 40% lower than those for tied-ridge tillage. When averaged across seasons and tillage systems, the highest gross margins (KES 8567 / ha) were obtained in sole cowpea cropping system, followed by sole maize with manure (KES 4070 / ha), intercrop (KES 864 / ha) and least (loss of KES 1330 / ha) in sole maize without manure cropping system. (author)

Transgene expression in cowpea ( Vigna unguiculata (L.) Walp ...

African Journals Online (AJOL)

Transgene expression in cowpea ( Vigna unguiculata (L.) Walp.) ... and Bar genes for β-glucuronidase expression and bialaphos resistance respectively. ... expression also showed positive signals under PCR and Southern analysis giving ...

Prioritising in situ conservation of crop resources: a case study of African cowpea (Vigna unguiculata).

Science.gov (United States)

Moray, C; Game, E T; Maxted, N

2014-06-17

Conserving crop wild relatives (CWR) is critical for maintaining food security. However, CWR-focused conservation plans are lacking, and are often based on the entire genus, even though only a few taxa are useful for crop improvement. We used taxonomic and geographic prioritisation to identify the best locations for in situ conservation of the most important (priority) CWR, using African cowpea (Vigna unguiculata (L.) Walp.) as a case study. Cowpea is an important crop for subsistence farmers in sub-Saharan Africa, yet its CWR are under-collected, under-conserved and under-utilised in breeding. We identified the most efficient sites to focus in situ cowpea CWR conservation and assessed whether priority CWR would be adequately represented in a genus-based conservation plan. We also investigated whether priority cowpea CWR are likely to be found in existing conservation areas and in areas important for mammal conservation. The genus-based method captured most priority CWR, and the distributions of many priority CWR overlapped with established conservation reserves and targets. These results suggest that priority cowpea CWR can be conserved by building on conservation initiatives established for other species.

Mutation breeding for disease resistance in food beans and cowpea in Kenya

International Nuclear Information System (INIS)

Onim, J.F.M.

1983-01-01

Ionizing radiation is being used in attempts to obtain more disease resistant variants of bean, cowpea and pigeon pea. In bean M 2 populations large genetic variation for morphological and physiological characters has been observed, but also differences in anthracnose, angular leaf spot and rust. Cowpea appears to be rather resistant to mutagen treatment and although some variation was induced, the number of mutants appears smaller than in Phaseolus vulgaris. (author)

Genotypic and phenotypic diversity does not affect productivity and drought response in competitive stands of Trifolium repens

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Heidrun eHuber

2016-03-01

Full Text Available Clonal plants can form dense canopies in which plants of different genetic origin are competing for the uptake of essential resources. The competitive relationships among these clones are likely to be affected by extreme environmental conditions, such as prolonged drought spells, which are predicted to occur more frequently due to global climate change. This, in turn, may alter characteristics of the ecological system and its associated functioning.We hypothesized that the relative success of individual clones will depend on the size of the ramets as ramets with larger leaves and longer petioles (large ramets were predicted to have a competitive advantage in terms of increased light interception over smaller-sized ramets. Under drier conditions the relative performances of genotypes were expected to change leading to a change in genotype ranking. We also hypothesized that increased genotypic and phenotypic diversity will increase stand performance and resistance to drought. These hypotheses and the mechanisms responsible for shifts in competitive relationships were investigated by subjecting genotypes of the important pasture legume Trifolium repens to competition with either genetically identical clones, genetically different but similarly sized clones, or genetically as well as morphologically different clones under well-watered and dry conditions.Competitive relationships were affected by ramet size with large genotypes outperforming small genotypes in diverse stands in terms of biomass production. However, large genotypes also produced relatively fewer ramets than small genotypes and could not benefit in terms of clonal reproduction from competing with smaller genotypes, indicating that evolutionary shifts in genotype composition will depend on whether ramet size or ramet number is under selection. In contrast to our hypotheses, diversity did not increase stand performance under different selection regimes and genotype ranking was hardly

Genotypic and Phenotypic Diversity Does Not Affect Productivity and Drought Response in Competitive Stands of Trifolium repens.

Science.gov (United States)

Huber, Heidrun; During, Heinjo J; Bruine de Bruin, Fabienne; Vermeulen, Peter J; Anten, Niels P R

2016-01-01

Clonal plants can form dense canopies in which plants of different genetic origin are competing for the uptake of essential resources. The competitive relationships among these clones are likely to be affected by extreme environmental conditions, such as prolonged drought spells, which are predicted to occur more frequently due to global climate change. This, in turn, may alter characteristics of the ecological system and its associated functioning. We hypothesized that the relative success of individual clones will depend on the size of the ramets as ramets with larger leaves and longer petioles (large ramets) were predicted to have a competitive advantage in terms of increased light interception over smaller-sized ramets. Under drier conditions the relative performances of genotypes were expected to change leading to a change in genotype ranking. We also hypothesized that increased genotypic and phenotypic diversity will increase stand performance and resistance to drought. These hypotheses and the mechanisms responsible for shifts in competitive relationships were investigated by subjecting genotypes of the important pasture legume Trifolium repens to competition with either genetically identical clones, genetically different but similarly sized clones, or genetically as well as morphologically different clones under well-watered and dry conditions. Competitive relationships were affected by ramet size with large genotypes outperforming small genotypes in diverse stands in terms of biomass production. However, large genotypes also produced relatively fewer ramets than small genotypes and could not benefit in terms of clonal reproduction from competing with smaller genotypes, indicating that evolutionary shifts in genotype composition will depend on whether ramet size or ramet number is under selection. In contrast to our hypotheses, diversity did not increase stand performance under different selection regimes and genotype ranking was hardly affected by soil

Transformation of Cowpea Vigna unguiculata with a Full-Length DNA Copy of Cowpea Mosaic Virus M-RNA

NARCIS (Netherlands)

Hille, Jacques; Goldbach, Rob

1987-01-01

A full-length DNA copy of the M-RNA of cowpea mosaic virus (CPMV), supplied with either the 35S promoter from cauliflower mosaic virus (CaMV) or the nopaline synthase promoter from Agrobacterium tumefaciens, was introduced into the T-DNA region of a Ti-plasmid-derived gene vector and transferred to

Removal of six pesticide residues in cowpea with alkaline electrolysed water.

Science.gov (United States)

Han, Yongtao; Song, Le; An, Quanshun; Pan, Canping

2017-06-01

Reduction of six pesticide residues (isoprocarb, chlorpyrifos, bifenthrin, beta-cypermethrin, difenoconazole and azoxystrobin) in cowpea by alkaline electrolysed water (AlEW) solutions with different pH was investigated. The commonly used washing treatments in household processing were used for comparison. The residue magnitudes were determined by gas chromatography coupled with tandem mass spectrometry (GC-MS/MS). Results showed that the removal effect of AlEW solution on the six pesticides was superior to tap water, 5% sodium chloride, 5% sodium carbonate and 5% acetic acid solution. AlEW with pH 12.2 had more potential to eliminate the six pesticides in cowpeas. Moreover, the reduction of pesticide residues gradually increased with the increase of washing time. This study demonstrated that AlEW solution with pH of 12.2 could be used to reduce pesticide residues on fresh cowpea samples. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Fate and distribution of lindane and endosulfan in maize and cowpea ecosystems respectively

International Nuclear Information System (INIS)

Yeboah, P.O.; Montford, K.G.; Klake, R.K.; Akpabli, C.K.

1997-01-01

A quantitative study is presented on linande and endosulfan residues in maize and cowpea ecosystems respectively. Both pesticides were found to dissipate very fast under the tropical Ghanaian conditions. The high rate of dissipation in leaves is attributed to the fact that the leaves were exposed to sunshine and wind leading to increased volatilisation. Endosulfan was found to dissipate faster from the cowpea ecosystem than lindane did in the maize ecosystem. The mean residue levels of lindane in maize grains were 0.02 μg g -1 ; whilst residue levels of endosulfan in cowpea seeds were 0.05 μg g -1 . These levels are lower than the maximum residue limits recognized as acceptable by the Codex Alimentarus Commission. (author). 11 refs, 7 tabs

Assessment of sorghum–cowpea intercrop system under water ...

African Journals Online (AJOL)

2016-04-02

Apr 2, 2016 ... In such instances, crop models can be used as decision support ... Planting dates (trigger season climate method, modelling and fixed date approaches), .... cowpea intercrop system for biomass accumulation (2.1%), water.

Seed yield and agronomic parameters of cowpea (Vigna ...

African Journals Online (AJOL)

Jane

2011-10-12

Oct 12, 2011 ... 1Department of Field Crops, Faculty of Agriculture, Bozok University, Sivas ... Key words: Vigna unguiculata, seed yield, thousand seed weight, Black Sea. INTRODUCTION. The cowpea (Vigna unguiculata L.) is an important.

Assembled genomic and tissue-specific transcriptomic data resources for two genetically distinct lines of Cowpea ( Vigna unguiculata (L.) Walp).

Science.gov (United States)

Spriggs, Andrew; Henderson, Steven T; Hand, Melanie L; Johnson, Susan D; Taylor, Jennifer M; Koltunow, Anna

2018-02-09

Cowpea ( Vigna unguiculata (L.) Walp) is an important legume crop for food security in areas of low-input and smallholder farming throughout Africa and Asia. Genetic improvements are required to increase yield and resilience to biotic and abiotic stress and to enhance cowpea crop performance. An integrated cowpea genomic and gene expression data resource has the potential to greatly accelerate breeding and the delivery of novel genetic traits for cowpea. Extensive genomic resources for cowpea have been absent from the public domain; however, a recent early release reference genome for IT97K-499-35 ( Vigna unguiculata  v1.0, NSF, UCR, USAID, DOE-JGI, http://phytozome.jgi.doe.gov/) has now been established in a collaboration between the Joint Genome Institute (JGI) and University California (UC) Riverside. Here we release supporting genomic and transcriptomic data for IT97K-499-35 and a second transformable cowpea variety, IT86D-1010. The transcriptome resource includes six tissue-specific datasets for each variety, with particular emphasis on reproductive tissues that extend and support the V. unguiculata v1.0 reference. Annotations have been included in our resource to allow direct mapping to the v1.0 cowpea reference. Access to this resource provided here is supported by raw and assembled data downloads.

Identification of candidate genes and molecular markers for heat-induced brown discoloration of seed coats in cowpea [Vigna unguiculata (L.) Walp].

Science.gov (United States)

Pottorff, Marti; Roberts, Philip A; Close, Timothy J; Lonardi, Stefano; Wanamaker, Steve; Ehlers, Jeffrey D

2014-05-01

Heat-induced browning (Hbs) of seed coats is caused by high temperatures which discolors the seed coats of many legumes, affecting the visual appearance and quality of seeds. The genetic determinants underlying Hbs in cowpea are unknown. We identified three QTL associated with the heat-induced browning of seed coats trait, Hbs-1, Hbs-2 and Hbs-3, using cowpea RIL populations IT93K-503-1 (Hbs positive) x CB46 (hbs negative) and IT84S-2246 (Hbs positive) x TVu14676 (hbs negative). Hbs-1 was identified in both populations, accounting for 28.3% -77.3% of the phenotypic variation. SNP markers 1_0032 and 1_1128 co-segregated with the trait. Within the syntenic regions of Hbs-1 in soybean, Medicago and common bean, several ethylene forming enzymes, ethylene responsive element binding factors and an ACC oxidase 2 were observed. Hbs-1 was identified in a BAC clone in contig 217 of the cowpea physical map, where ethylene forming enzymes were present. Hbs-2 was identified in the IT93K-503-1 x CB46 population and accounted for of 9.5 to 12.3% of the phenotypic variance. Hbs-3 was identified in the IT84S-2246 x TVu14676 population and accounted for 6.2 to 6.8% of the phenotypic variance. SNP marker 1_0640 co-segregated with the heat-induced browning phenotype. Hbs-3 was positioned on BAC clones in contig512 of the cowpea physical map, where several ACC synthase 1 genes were present. The identification of loci determining heat-induced browning of seed coats and co-segregating molecular markers will enable transfer of hbs alleles into cowpea varieties, contributing to higher quality seeds.

Cowpea viruses: Effect of single and mixed infections on symptomatology and virus concentration

Directory of Open Access Journals (Sweden)

Nsa Imade Y

2007-09-01

Full Text Available Abstract Natural multiple viral infections of cultivated cowpeas have been reported in Nigeria. In this study, three Nigerian commercial cowpea cultivars ("Olo 11", "Oloyin" and "White" and two lines from the IITA (IT86D- 719 and TVU 76 were mechanically inoculated with Cowpea aphid-borne mosaic virus (CABMV, Bean southern mosaic virus (SBMV and Cowpea mottle virus (CMeV singly, as well as in all possible combinations at 10, 20 and 30 days after planting (DAP. Samples of leaves or stems were collected at 10, 20 and 30 days after inoculation (DAI and analyzed for relative virus concentration by Enzyme-Linked Immunosrbent Assay. All the cultivars and lines {CVS/L} were susceptible to the viruses but the commercial CVS showed more severe symptoms and had relatively higher viral concentration. In single virus infections, CABMV which induced the most severe symptoms had absorbance values (at 405 nm of 0.11 to 0.46 while SBMV and CMeV which induced moderate symptoms had virus titre of 0.74 to 1.99 and 0.11 to 0.90 respectively. Plants inoculated 10 DAP had significantly higher virus concentration than those inoculated 30 DAP. In mixed infections involving CABMV (10 DAP apical necrosis and death were observed in commercial cultivars "Olo 11" and "White". Enhancement of CMeV titers were observed in plants infected with CMeV + CABMV. Multiple viral infections of cowpeas may result in complete yield loss, hence, the availability of seeds of cultivars with a high level of multiple virus resistance is recommended as a means of control.

Antioxidant Activity of the Extracts of Some Cowpea (Vigna unguiculata (L Walp. Cultivars Commonly Consumed in Pakistan

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Vincenzo De Feo

2013-02-01

Full Text Available The present investigation has been carried out to determine the antioxidant activity of the methanolic extracts obtained from four cultivars of cowpea (Vigna unguiculata (L Walp. seeds. Phenolic compounds present in the extracts showed the antioxidant and antiradical properties when investigated using a linoleic acid peroxidation model, FRAP, ORAC and TRAP assays, as well as DPPH, hydroxyl, nitric oxide and superoxide radical scavenging activity. The HPLC analysis of the cowpea extracts showed the presence of neochlorogenic acid, chlorogenic acid and caffeic acids. The results indicated that methanolic extract of the cowpea resembled in the aforementioned activities those from other leguminous seeds and pulses. Phenolic constituents contained in cowpea may have a future role as ingredients in the development of functional foods.

inhibition of germination and growth behavior of some cowpea

African Journals Online (AJOL)

DR. AMIN

2011-12-02

Dec 2, 2011 ... COWPEA VARIETIES USING NEEM (AZADIRACTA INDICA) LEAF WATER. EXTRACTS ... Keywords: Neem, Allelopathic effect, Leaf extract, Germination, Growth behavior ... and lotion today, as well as biological insecticide.

Gamma radiosensitivity in common bean plant and cowpea

International Nuclear Information System (INIS)

Guimaraes, Sandra da Silva; Colaco, Waldeciro

2002-01-01

An indispensable step in mutation induction experiments is the determination of the sensitivity to mutagens to be used. Taking this into consideration the radiosensitivity of bean cultivars Carioca, Princesa (P. vulgaris L.), and IPA-206 [V. unguiculata (L.) Walp] to gamma rays from a 60 Co source was evaluated. Sets of seeds (40 seeds/sample) were irradiated with 100, 150, 200, 250 Gy, and compared to a control without irradiation (0 Gy), under greenhouse conditions. Bean and cowpea seeds were respectively inoculated with a suspension of Rhizobium (SEMIA-4077) and Bradyrhizobium (SEMIA-6145) strains. The radiosensitivity was evaluated through seedling height reduction determined at 15 days after emergence (15-DAE), and also through dry matter yield of above-ground part and root nodules at 40-DAE. Seedling height was significantly reduced with increased dose of radiation in relation to the control. The dose causing reduction of 50% seedling height for P. vulgaris cultivar Princesa was set up between 150-250 Gy. Cowpea (IPA-206) was less sensitive to radiation than common bean cultivars, considering the dose range of radiation studied, and a 75% seedling height reduction was reached in the range of 150-250 Gy. Dry mater yield of the above-ground part, root and nodule, were inversely related to the doses. It is recommended a dose range of 300-350 Gy for mutation breeding purposes using the cowpea cultivar (IPA-206). (author)

Effects of light quality on pod elongation in soybean (Glycine max (L.) Merr.) and cowpea (Vigna unguiculata (L.) Walp.).

Science.gov (United States)

Tanaka, Seiya; Ario, Nobuyuki; Nakagawa, Andressa Camila Seiko; Tomita, Yuki; Murayama, Naoki; Taniguchi, Takatoshi; Hamaoka, Norimitsu; Iwaya-Inoue, Mari; Ishibashi, Yushi

2017-06-03

Soybean pods are located at the nodes, where they are in the shadow, whereas cowpea pods are located outside of the leaves and are exposed to sunlight. To compare the effects of light quality on pod growth in soybean and cowpea, we measured the length of pods treated with white, blue, red or far-red light. In both species, pods elongated faster during the dark period than during the light period in all light treatments except red light treatment in cowpea. Red light significantly suppressed pod elongation in soybean during the dark and light periods. On the other hand, the elongation of cowpea pods treated with red light markedly promoted during the light period. These results suggested that the difference in the pod set sites between soybean and cowpea might account for the difference in their red light responses for pod growth.

Modeling of the water uptake process for cowpea seeds (vigna unguiculata l.) under common treatment and microwave treatment

International Nuclear Information System (INIS)

Demirhan, E.

2015-01-01

The water uptake kinetics of cowpea seeds were carried out at two different water absorption treatments - common treatment and microwave treatment - to evaluate the effects of rehydration temperatures and microwave output powers on rehydration. Water uptake of cowpea seeds during soaking in water was studied at various temperatures of 20 - 45 degree C, and at various microwave output powers of 180 - 900 W. As the rehydration temperature and microwave output power increased, the water uptake of cowpea seeds increased and the rehydration time decreased. The Peleg and Richards Models were capable of predicting water uptake of cowpea seeds undergoing common treatment and microwave treatment, respectively. The effective diffusivity values were evaluated by fitting experimental absorption data to Fick second law of diffusion. The effective diffusivity coefficients for cowpea seeds varied from 7.75*10-11 to 1.99*10-10 m2/s and from 2.23*10-9 to 9.78*10-9 m2/s for common treatment and microwave treatment, respectively. (author)

Cloning of cDNA sequences encoding cowpea (Vigna unguiculata) vicilins: Computational simulations suggest a binding mode of cowpea vicilins to chitin oligomers.

Science.gov (United States)

Rocha, Antônio J; Sousa, Bruno L; Girão, Matheus S; Barroso-Neto, Ito L; Monteiro-Júnior, José E; Oliveira, José T A; Nagano, Celso S; Carneiro, Rômulo F; Monteiro-Moreira, Ana C O; Rocha, Bruno A M; Freire, Valder N; Grangeiro, Thalles B

2018-05-27

Vicilins are 7S globulins which constitute the major seed storage proteins in leguminous species. Variant vicilins showing differential binding affinities for chitin have been implicated in the resistance and susceptibility of cowpea to the bruchid Callosobruchus maculatus. These proteins are members of the cupin superfamily, which includes a wide variety of enzymes and non-catalytic seed storage proteins. The cupin fold does not share similarity with any known chitin-biding domain. Therefore, it is poorly understood how these storage proteins bind to chitin. In this work, partial cDNA sequences encoding β-vignin, the major component of cowpea vicilins, were obtained from developing seeds. Three-dimensional molecular models of β-vignin showed the characteristic cupin fold and computational simulations revealed that each vicilin trimer contained 3 chitin-binding sites. Interaction models showed that chito-oligosaccharides bound to β-vignin were stabilized mainly by hydrogen bonds, a common structural feature of typical carbohydrate-binding proteins. Furthermore, many of the residues involved in the chitin-binding sites of β-vignin are conserved in other 7S globulins. These results support previous experimental evidences on the ability of vicilin-like proteins from cowpea and other leguminous species to bind in vitro to chitin as well as in vivo to chitinous structures of larval C. maculatus midgut. Copyright © 2018. Published by Elsevier B.V.

Complete genomic characterization of milk vetch dwarf virus isolates from cowpea and broad bean in Anhui province, China.

Science.gov (United States)

Zhang, Chenhua; Zheng, Hongying; Yan, Dankan; Han, Kelei; Song, Xijiao; Liu, Yong; Zhang, Dongfang; Chen, Jianping; Yan, Fei

2017-08-01

Cowpea and broad bean plants showing severe stunting and leaf rolling symptoms were observed in Hefei city, Anhui province, China, in 2014. Symptomatic plants from both species were shown to be infected with milk vetch dwarf virus (MDV) by PCR. The complete genomes of MDV isolates from cowpea and broad bean were sequenced. Each of them had eight genomic DNAs that differed between the two isolates by 10.7% in their overall nucleotide sequences. In addition, the MDV genomes from cowpea and broad bean were associated with two and three alphasatellite DNAs, respectively. This is the first report of MDV on cowpea in China and the first complete genome sequences of Chinese MDV isolates.

Genetics evaluation of phosphorus utilization in tropical cowpea ...

African Journals Online (AJOL)

Genetics evaluation of phosphorus utilization in tropical cowpea (Vigna ... that responds negatively to RP, using generation mean analysis of the parents, their ... was observed to be below the critical level, phosphorus uptake in the F1 and the ...

Identification of water storage tissue in the stem of cowpea plant (Vigna unguliculata Walp) by neutron radiography

International Nuclear Information System (INIS)

Nakanishi, T.M.; Don-Jin, K.; Ishii, R.; Matsubayashi, M.

1999-01-01

Cowpea (Vigna unguliculata Walp) is considered one of the most drought resistant species among the pulse crops. It was suggested that in the lower part of the stem, parenchymatous tissue for storing water has been developed for the function of drought resistance. However, such tissue has not been identified yet. In order to identify the water storing tissue in the stem of cowpea plant, the authors performed neutron radiography, which provides a non-destructive image of water distribution pattern in a plant. Common bean plant and soybean plant were used as references. Comparing the neutron radiograph for the stems of the plants, i.e., cowpea, common bean and soybean plants, the parenchymatous tissue with water storing function was distinguished in the intermode between primary leaf and the first trifoliate leaf specifically in cowpea plant. (author)

Population structure analysis and association mapping of seed antioxidant content in USDA cowpea (Vigna unguiculata L. Walp.) core collection using SNPs

Science.gov (United States)

Cowpea (Vigna unguiculata (L) Walp.) is an important legume and the antioxidants in cowpea seeds have been recognized as health-promoting compounds for human. The objectives of this study were to analyze the population structure of cowpea collections using single nucleotide polymorphism (SNP) and to...

Common bean and cowpea improvement in Angola

Science.gov (United States)

During 2014 and 2015, the Instituto de Investigação Agronómica (IIA) evaluated the performance of common bean (Phaselolus vulgaris L.) breeding lines and improved cowpea (Vigna unguiculata L. Walp.) varieties. The field experiments were planted in the lowlands at Mazozo and in the highlands at Chian...

Effect of variety mixtures on cowpea (Vigna unguiculata) vegetable ...

African Journals Online (AJOL)

jokonya

AN EVALUATION OF SIX COWPEA VARIETIES GROWN ... provide cheap sources of protein, micronutrients and mineral elements that can ... traditional vegetables is that, these leafy vegetables are present in most home ..... REFERENCES. 1.

Effect of Seed Priming on Germination Properties and Seedling Establishment of Cowpea (Vigna sinensis

Directory of Open Access Journals (Sweden)

Hamdollah ESKANDARI

2011-11-01

Full Text Available Early emergence and stand establishment of cowpea are considered to be the most important yield-contributing factors in rainfed areas. Laboratory tests and afield experiment were conducted in RCB design in 2011 at a research farm in Ramhormoz, Iran, to evaluate the effects of hydropriming (8, 12 and 16 hours duration and halo priming (solutions of 1.5% KNO3 and 0.8% NaCl on seedling vigor and field establishment of cowpea. Analysis of variance of laboratory data showed that hydropriming significantly improved germination rate, seed vigor index, and seedling dry weights. However, germination percentage for seeds primed with KNO3 and non-primed seeds were statistically similar, but higher than those for NaCl priming. Overall, hydropriming treatment was comparatively superior in the laboratory tests. Invigoration of cowpea seeds by hydropriming and NaCl priming resulted in higher seedling emergence and establishment in the field, compared to control and seed priming with KNO3. Seedling emergence rate was also enhanced by priming seeds with water, suggesting that hydropriming is a simple, low cost and environmentally friendly technique for improving seed and seedling vigor of cowpea.

A note on outbreak of cowpea mild mottle virus (CPMMV) in common bean in the River Nile State, Sudan

International Nuclear Information System (INIS)

Hamed, A. A.; Elkhair, J.; Elfaha, A.

2010-01-01

An outbreak of a devastating virus disease occurred in common ben (phaseolus vulgaris) in Berber area, the River Nile State, during the 2004/2005 cropping season, with symptoms of stunting and yellowing. The disease incidence reached a level of more than 85% in all visited fields. One hundred fifty symptomatic samples, collected from different fields at Hudeiba, Berber and Shendi were blotted on nitrocellulose membranes and tested for the presence of different viruses, using the tissue blot immunoassay (TBIA) technique. The results of the serological tests revealed that 95% of the samples were positive for cowpea mild mottle virus (CPMMV). Among the common bean genotypes screened for resistance to CPMMV, only RO/2/1 and Giza 3 were resistant to the disease.(Author)

Using violet laser-induced chlorophyll fluorescence emission spectra for crop yield assessment of cowpea (Vigna unguiculata (L) Walp) varieties

Science.gov (United States)

Anderson, Benjamin; Buah-Bassuah, Paul K.; Tetteh, Jonathan P.

2004-07-01

The use of violet laser-induced chlorophyll fluorescence (LICF) emission spectra to monitor the growth of five varieties of cowpea in the University of Cape Coast Botanical Garden is presented. Radiation from a continuous-wave violet laser diode emitting at 396 nm through a fibre is closely incident on in vivo leaves of cowpea to excite chlorophyll fluorescence, which is detected by an integrated spectrometer with CCD readout. The chlorophyll fluorescence spectra with peaks at 683 and 731 nm were used for growth monitoring of the cowpea plants over three weeks and analysed using Gaussian spectral functions with curve fitted parameters to determine the peak positions, area under the spectral curve and the intensity ratio F683/F731. The variation in the intensity ratio of the chlorophyll bands showed sensitive changes indicating the photosynthetic activity of the cowpea varieties. A discussion of the fluorescence result as compared to conventional assessment is presented with regard to discrimination between the cowpea varieties in terms of crop yield performance.

Cowpea Mosaic Virus-Encoded Protease Does Not Recognize Primary Translation Products of M RNAs from Other Comoviruses

OpenAIRE

Goldbach, Rob; Krijt, Jette

1982-01-01

The protease encoded by the large (B) RNA segment of cowpea mosaic virus was tested for its ability to recognize the in vitro translation products of the small (M) RNA segment from the comoviruses squash mosaic virus, red clover mottle virus, and cowpea severe mosaic virus (CPsMV, strains Dg and Ark), and from the nepovirus tomato black ring virus. Like M RNA from cowpea mosaic virus, the M RNAs from squash mosaic virus, red clover mottle virus, CPsMV-Dg, and CPsMV-Ark were all translated int...

serological detection of seed borne viruses in cowpea regenerated

African Journals Online (AJOL)

Administrator

out to detect the presence of seed borne viruses in fourteen cowpea accessions ... were serologically indexed to detect any seed-borne viruses after acclimatisation to screen house conditions. The .... showed external virus-like symptoms were.

Short communication Effect of pesticides applied in cowpea ...

African Journals Online (AJOL)

Mrs Mabel Antwi

2014-08-02

Aug 2, 2014 ... cowpea crop, application of lambda cyhalothrin, dimethoate, and cypermethrin is recommended (Afun et al.,. 1991) and commonly practised in Ghana and other sub-Saharan African countries. Inherent problems of pesticide residue accumulation and degradation compounds in edible tissues (Laben, 1968) ...

Nitrogen credits from cowpea, soybean, groundnut and Mucuna to

African Journals Online (AJOL)

komla

fixing capacity. A field study was conducted in 1999 and 2000 at Ejura in the forest savanna transition ..... plants. Soybean, cowpea, and groundnut could be susceptible to various root knot nematode ..... Maize and legumes production guide.

Growth and Yield Responses of Vegetable Cowpea ( Vigna ...

African Journals Online (AJOL)

The amendment of acidic soil with lime application enhances nutrient availability for optimum vegetable cowpea production. Field experiments were conducted in the teaching and research farm of Michael Okpara University of Agriculture, Umudike during 2006 and 2007 cropping seasons to determine the growth and yield ...

Plants regeneration from African cowpea variety (Vigna unguiculata ...

African Journals Online (AJOL)

STORAGESEVER

2008-08-18

Aug 18, 2008 ... Vigna unguiculata (L.) Walp. plant was efficiently regenerated from cotyledonary node explants. The shoots multiplication rate was ... Africa, insect pests are often responsible for 100% losses of cowpea yields (Singh and .... 26 days after acclimatization first flower buds were observed; thus plants were ...

Cowpea mosaic virus: effects on host cell processes

NARCIS (Netherlands)

Pouwels, J.; Carette, J.E.; Lent, van J.; Wellink, J.E.

2002-01-01

Taxonomy: Cowpea mosaic virus (CPMV) is the type member of the Comoviridae and bears a strong resemblance to animal picornaviruses, both in gene organization and in the amino acid sequence of replication proteins. Little systematic work has been done to compare isolates of the virus from different

31 -34_Yusuf N

African Journals Online (AJOL)

DR. AMINU

cowpea genotypes were studied under different daylenght, the ... The data obtained were subjected to analysis of ... (growth habit) which are affected by temperature and ... 79.00 abc. 67.16 ab. 72.10 a. 81.00 abc. 109.66 a. 96.20 ab. 108.00b.

Transformation of Cowpea Vigna unguiculata Cells with an Antibiotic Resistance Gene Using a Ti-Plasmid-Derived Vector

NARCIS (Netherlands)

Hille, Jacques; Goldbach, Rob

1986-01-01

A chimaeric antibiotic resistance gene was transferred to cowpea (Vigna unguiculata), a member of the legume family. This transfer was established by inoculating cowpea leaf discs with an Agrobacterium tumefaciens strain harboring a Ti-plasmid-derived vector that contained two copies of a chimaeric

CGKB: an annotation knowledge base for cowpea (Vigna unguiculata L. methylation filtered genomic genespace sequences

Directory of Open Access Journals (Sweden)

Spraggins Thomas A

2007-04-01

Full Text Available Abstract Background Cowpea [Vigna unguiculata (L. Walp.] is one of the most important food and forage legumes in the semi-arid tropics because of its ability to tolerate drought and grow on poor soils. It is cultivated mostly by poor farmers in developing countries, with 80% of production taking place in the dry savannah of tropical West and Central Africa. Cowpea is largely an underexploited crop with relatively little genomic information available for use in applied plant breeding. The goal of the Cowpea Genomics Initiative (CGI, funded by the Kirkhouse Trust, a UK-based charitable organization, is to leverage modern molecular genetic tools for gene discovery and cowpea improvement. One aspect of the initiative is the sequencing of the gene-rich region of the cowpea genome (termed the genespace recovered using methylation filtration technology and providing annotation and analysis of the sequence data. Description CGKB, Cowpea Genespace/Genomics Knowledge Base, is an annotation knowledge base developed under the CGI. The database is based on information derived from 298,848 cowpea genespace sequences (GSS isolated by methylation filtering of genomic DNA. The CGKB consists of three knowledge bases: GSS annotation and comparative genomics knowledge base, GSS enzyme and metabolic pathway knowledge base, and GSS simple sequence repeats (SSRs knowledge base for molecular marker discovery. A homology-based approach was applied for annotations of the GSS, mainly using BLASTX against four public FASTA formatted protein databases (NCBI GenBank Proteins, UniProtKB-Swiss-Prot, UniprotKB-PIR (Protein Information Resource, and UniProtKB-TrEMBL. Comparative genome analysis was done by BLASTX searches of the cowpea GSS against four plant proteomes from Arabidopsis thaliana, Oryza sativa, Medicago truncatula, and Populus trichocarpa. The possible exons and introns on each cowpea GSS were predicted using the HMM-based Genscan gene predication program and the

Comparative evaluation of six storage methods for postharvest preservation of cowpea grain

KAUST Repository

Baoua, I. B.

2012-04-01

Several technologies reputedly minimize losses of stored cowpea grain to bruchid beetles on low resource farms in Africa. Side by side comparison of these different postharvest storage methods can provide the basis for deciding which performs best. We compared six different technologies for cowpea storage: (1) grain mixed with ash; (2) mixed with sand; (3) fumigated with phostoxin; (4) admixed with the stems and leaves of . Boscia senegalensis (Pers) Lam ex Poir, a potential botanical insecticide; (5) disinfested using a solar heater, and; (6) hermetically sealed in triple-layer plastic bags. Sampling was done at thirty-day intervals over five months of storage. Counts were made of (i) adult emergence holes, (ii) dead larvae and (iii) surviving bruchid larvae and adults. Controls, which consisted of infested cowpea grain stored in cloth bags, were damaged extensively. . Boscia senegalensis-treated grain suffered similar severe damage. All other treatments suppressed bruchid population increases as was evident from the much lower counts of emergence holes and lower numbers of surviving or dead insects. © 2012 Elsevier Ltd.

Comparative evaluation of six storage methods for postharvest preservation of cowpea grain

KAUST Repository

Baoua, I. B.; Amadou, L.; Margam, V.; Murdock, L. L.

2012-01-01

Several technologies reputedly minimize losses of stored cowpea grain to bruchid beetles on low resource farms in Africa. Side by side comparison of these different postharvest storage methods can provide the basis for deciding which performs best. We compared six different technologies for cowpea storage: (1) grain mixed with ash; (2) mixed with sand; (3) fumigated with phostoxin; (4) admixed with the stems and leaves of . Boscia senegalensis (Pers) Lam ex Poir, a potential botanical insecticide; (5) disinfested using a solar heater, and; (6) hermetically sealed in triple-layer plastic bags. Sampling was done at thirty-day intervals over five months of storage. Counts were made of (i) adult emergence holes, (ii) dead larvae and (iii) surviving bruchid larvae and adults. Controls, which consisted of infested cowpea grain stored in cloth bags, were damaged extensively. . Boscia senegalensis-treated grain suffered similar severe damage. All other treatments suppressed bruchid population increases as was evident from the much lower counts of emergence holes and lower numbers of surviving or dead insects. © 2012 Elsevier Ltd.

Varying plant density and harvest time to optimize cowpea leaf yield and nutrient content

Science.gov (United States)

Ohler, T. A.; Nielsen, S. S.; Mitchell, C. A.

1996-01-01

Plant density and harvest time were manipulated to optimize vegetative (foliar) productivity of cowpea [Vigna unguiculata (L.) Walp.] canopies for future dietary use in controlled ecological life-support systems as vegetables or salad greens. Productivity was measured as total shoot and edible dry weights (DW), edible yield rate [(EYR) grams DW per square meter per day], shoot harvest index [(SHI) grams DW per edible gram DW total shoot], and yield-efficiency rate [(YER) grams DW edible per square meter per day per grams DW nonedible]. Cowpeas were grown in a greenhouse for leaf-only harvest at 14, 28, 42, 56, 84, or 99 plants/m2 and were harvested 20, 30, 40, or 50 days after planting (DAP). Shoot and edible dry weights increased as plant density and time to harvest increased. A maximum of 1189 g shoot DW/m2 and 594 g edible DW/m2 were achieved at an estimated plant density of 85 plants/m2 and harvest 50 DAP. EYR also increased as plant density and time to harvest increased. An EYR of 11 g m-2 day-1 was predicted to occur at 86 plants/m2 and harvest 50 DAP. SHI and YER were not affected by plant density. However, the highest values of SHI (64%) and YER (1.3 g m-2 day-1 g-1) were attained when cowpeas were harvested 20 DAP. The average fat and ash contents [dry-weight basis (dwb)] of harvested leaves remained constant regardless of harvest time. Average protein content increased from 25% DW at 30 DAP to 45% DW at 50 DAP. Carbohydrate content declined from 50% DW at 30 DAP to 45% DW at 50 DAP. Total dietary fiber content (dwb) of the leaves increased from 19% to 26% as time to harvest increased from 20 to 50 days.

Needs assessment of cowpea production practices, constraints and ...

African Journals Online (AJOL)

STORAGESEVER

2009-10-19

Oct 19, 2009 ... worsen the limitations to cowpea production in these provinces. Lack of .... avert risk, crop failure and distribution of farm labour. (Singh et al. ... turity groups was based on the length of rainfall. Farmer ... The market potential for bambara groundnut. ... Management of productivity of major cropping system.

Effect of different irrigation systems on root growth of maize and cowpea plants in sandy soil

Directory of Open Access Journals (Sweden)

Noha A. Mahgoub

2017-10-01

Full Text Available A field experiment was conducted at the Experimental Farm, Faculty of Agriculture, Suez Canal University to study the influence of different irrigation systems on root length density and specific root length of maize and cowpea plants cultivated in sandy soil. Three irrigation systems (Surface, drip and sprinkler irrigation were used in this study. The NPK fertilizers were applied as recommended doses for maize and cowpea. Root samples were collected from the soil profile below one plant (maize and cowpea which was irrigated by the three irrigation systems by using an iron box (30 cm× 20 cm which is divided into 24 small boxes each box is (5× 5 × 5 cm. At surface irrigation, root length density of cowpea reached to soil depth 30-40cm with lateral distances 5-10 cm and 15-20 cm. Vertical distribution of root length density of maize was increased with soil depth till 20-25 cm, and then it decreased till soil depth 35-40cm. Under drip irrigation, root length density of cowpea increased horizontally from 0-5cm to 10-15cm then it decreased till soil depth 25-30 cm and below this depth root length density disappeared. For the root length density and specific root length of maize under drip irrigation, the data showed that root length density and specific root length decreased with increasing in soil depth. The root length density of cowpea under sprinkler irrigation at 0-5cm disappeared from horizontal distance at 25-30 cm. The data showed that root length density of maize under sprinkler irrigation was higher at the soil top layers 0-5 cm and 5-10 cm than other layers from 10-40 cm.

Polyphenolic extracts from cowpea (Vigna unguiculata) protect colonic myofibroblasts (CCD18Co cells) from lipopolysaccharide (LPS)-induced inflammation--modulation of microRNA 126.

Science.gov (United States)

Ojwang, Leonnard O; Banerjee, Nivedita; Noratto, Giuliana D; Angel-Morales, Gabriela; Hachibamba, Twambo; Awika, Joseph M; Mertens-Talcott, Susanne U

2015-01-01

Cowpea (Vigna unguiculata) is a drought tolerant crop with several agronomic advantages over other legumes. This study evaluated varieties from four major cowpea phenotypes (black, red, light brown and white) containing different phenolic profiles for their anti-inflammatory property on non-malignant colonic myofibroblasts (CCD18Co) cells challenged with an endotoxin (lipopolysaccharide, LPS). Intracellular reactive oxygen species (ROS) assay on the LPS-stimulated cells revealed antioxidative potential of black and red cowpea varieties. Real-time qRT-PCR analysis in LPS-stimulated cells revealed down-regulation of proinflammatory cytokines (IL-8, TNF-α, VCAM-1), transcription factor NF-κB and modulation of microRNA-126 (specific post-transcriptional regulator of VCAM-1) by cowpea polyphenolics. The ability of cowpea polyphenols to modulate miR-126 signaling and its target gene VCAM-1 were studied in LPS-stimulated endothelial cells transfected with a specific inhibitor of miR-126, and treated with 10 mg GAE/L black cowpea extract where the extract in part reversed the effect of the miR-126 inhibitor. This suggests that cowpea may exert their anti-inflammatory activities at least in part through induction of miR-126 that then down-regulate VCAM-1 mRNA and protein expressions. Overall, Cowpea therefore is promising as an anti-inflammatory dietary component.

Yield Performance of Some Cowpea Varieties under Sole and ...

African Journals Online (AJOL)

Nekky Umera

The mean number of pod/plant, pod weight and seed yield of the cowpea varieties ... pattern of peasant farmers in Nigeria. Some of the advantages ... in maize-pigeon pea intercropping system as compared to sole crops. While intercropping ...

Cowpea Mosaic Virus-Encoded Protease Does Not Recognize Primary Translation Products of M RNAs from Other Comoviruses.

Science.gov (United States)

Goldbach, R; Krijt, J

1982-09-01

The protease encoded by the large (B) RNA segment of cowpea mosaic virus was tested for its ability to recognize the in vitro translation products of the small (M) RNA segment from the comoviruses squash mosaic virus, red clover mottle virus, and cowpea severe mosaic virus (CPsMV, strains Dg and Ark), and from the nepovirus tomato black ring virus. Like M RNA from cowpea mosaic virus, the M RNAs from squash mosaic virus, red clover mottle virus, CPsMV-Dg, and CPsMV-Ark were all translated into two large polypeptides with apparent molecular weights which were different for each virus and even for the two CPsMV strains. Neither the in vitro products from squash mosaic virus, red clover mottle virus, and CPsMV M RNAs nor the in vitro product from tomato black ring virus RNA-2 were processed by the cowpea mosaic virus-encoded protease, indicating that the activity of this enzyme is highly specific.

A compendium of transcription factor and Transcriptionally active protein coding gene families in cowpea (Vigna unguiculata L.).

Science.gov (United States)

Misra, Vikram A; Wang, Yu; Timko, Michael P

2017-11-22

Cowpea (Vigna unguiculata (L.) Walp.) is the most important food and forage legume in the semi-arid tropics of sub-Saharan Africa where approximately 80% of worldwide production takes place primarily on low-input, subsistence farm sites. Among the major goals of cowpea breeding and improvement programs are the rapid manipulation of agronomic traits for seed size and quality and improved resistance to abiotic and biotic stresses to enhance productivity. Knowing the suite of transcription factors (TFs) and transcriptionally active proteins (TAPs) that control various critical plant cellular processes would contribute tremendously to these improvement aims. We used a computational approach that employed three different predictive pipelines to data mine the cowpea genome and identified over 4400 genes representing 136 different TF and TAP families. We compare the information content of cowpea to two evolutionarily close species common bean (Phaseolus vulgaris), and soybean (Glycine max) to gauge the relative informational content. Our data indicate that correcting for genome size cowpea has fewer TF and TAP genes than common bean (4408 / 5291) and soybean (4408/ 11,065). Members of the GROWTH-REGULATING FACTOR (GRF) and Auxin/indole-3-acetic acid (Aux/IAA) gene families appear to be over-represented in the genome relative to common bean and soybean, whereas members of the MADS (Minichromosome maintenance deficient 1 (MCM1), AGAMOUS, DEFICIENS, and serum response factor (SRF)) and C2C2-YABBY appear to be under-represented. Analysis of the AP2-EREBP APETALA2-Ethylene Responsive Element Binding Protein (AP2-EREBP), NAC (NAM (no apical meristem), ATAF1, 2 (Arabidopsis transcription activation factor), CUC (cup-shaped cotyledon)), and WRKY families, known to be important in defense signaling, revealed changes and phylogenetic rearrangements relative to common bean and soybean that suggest these groups may have evolved different functions. The availability of detailed

Simple Screening Methods for Drought and Heat Tolerance in Cowpea

International Nuclear Information System (INIS)

Singh, B. B.

2000-10-01

Success in breeding for drought tolerance has not been as pronounced as for other traits. This is partly due to lack of simple, cheap and reliable screening methods to select drought tolerant plants/progenies from the segregating populations and partly due to complexity of factors involved in drought tolerance. Measuring drought tolerance through physiological parameters is expensive, time consuming and difficult to use for screening large numbers of lines and segregating populations. Since several factors/mechanisms (in shoot and root) operate independently and/or jointly to enable plants to cope with drought stress, drought tolerance appears as a complex trait. However, if these factors/mechanisms can be separated and studied individually, the components leading to drought tolerance will appear less complex and may be easy to manipulate by breeders. We have developed a simple box screening method for shoot drought tolerance in cowpea, which eliminates the effects of roots and permits non-destructive visual identification of shoot dehydration tolerance. We have also developed a 'root-box pin-board' method to study two dimensional root architecture of individual plants. Using these methods, we have identified two mechanisms of shoot drought tolerance in cowpea which are controlled by single dominant genes and major difference for root architecture among cowpea varieties. Combining deep and dense root system with shoot dehydration tolerance results into highly drought tolerant plants

Identification of cowpea cultivars for low phosphorus soils of Nigeria

International Nuclear Information System (INIS)

Afolabi, N.O.; Ogunbodede, B.A.; Adediran, J.A.

1996-01-01

Twenty cultivars of cowpea, Vigna unguiculata, adapted to the Nigerian ecologies were screened to identify cultivars which can give high and sustainable yields when grown on soils with low available phosphorus in a sub-humid climate. Some cultivars including TVX3236, AFB1757, Ogunfowokan and K-28 gave three to four times higher grain yields than the other cultivars at zero phosphorus supply. While phosphorus application reduced grain yield in most of the cultivars with marked reduction in the higher yielding cultivars, low yielding cultivars tended to show some yield increase. Phosphorus use efficiency of the roots, stem or leaves was not significantly correlated with grain yield when 60 KgP/ha was applied. Reduction in yield due to phosphorus application might be due to induced Zn deficiency as Zn supply in these soils has been found to be inherently low. High grain yielding capacity without fertilizer phosphorus application was generally positively correlated with high vegetative shoot dry matter production. However, no clear relationship could be found between grain yield and root dry matter at maturity. It is concluded that selection for phosphorus efficiency in cowpea can substantially contribute to higher cowpea productivity and the farmers income on soils low in available phosphorus in the sub-humid areas of Nigeria. (author). 5 refs, 2 figs, 2 tabs

Identification of cowpea cultivars for low phosphorus soils of Nigeria

Energy Technology Data Exchange (ETDEWEB)

Afolabi, N O; Ogunbodede, B A; Adediran, J A [Obafemi Awolowo Univ., Ibadan (Nigeria). Inst. of Agricultural Research and Training

1996-07-01

Twenty cultivars of cowpea, Vigna unguiculata, adapted to the Nigerian ecologies were screened to identify cultivars which can give high and sustainable yields when grown on soils with low available phosphorus in a sub-humid climate. Some cultivars including TVX3236, AFB1757, Ogunfowokan and K-28 gave three to four times higher grain yields than the other cultivars at zero phosphorus supply. While phosphorus application reduced grain yield in most of the cultivars with marked reduction in the higher yielding cultivars, low yielding cultivars tended to show some yield increase. Phosphorus use efficiency of the roots, stem or leaves was not significantly correlated with grain yield when 60 KgP/ha was applied. Reduction in yield due to phosphorus application might be due to induced Zn deficiency as Zn supply in these soils has been found to be inherently low. High grain yielding capacity without fertilizer phosphorus application was generally positively correlated with high vegetative shoot dry matter production. However, no clear relationship could be found between grain yield and root dry matter at maturity. It is concluded that selection for phosphorus efficiency in cowpea can substantially contribute to higher cowpea productivity and the farmers income on soils low in available phosphorus in the sub-humid areas of Nigeria. (author). 5 refs, 2 figs, 2 tabs.

Partial Molecular Characterization Of Cowpea Stunt Isolates Of ...

African Journals Online (AJOL)

Partial molecular characterization of the coat protein of the cowpea stunt-causing isolates of Cucumber Mosaic Virus (CMV) from Arkansas and Georgia revealed that both isolates of CMV belong to CMV subgroup I and differ at eight nucleotides positions, resulting in two amino acids difference. There was only one amino ...

Quixotic coupling between irrigation system and maize-cowpea ...

African Journals Online (AJOL)

A study was conducted at the Research and Experimental Station, Faculty of Agriculture, Ain Shams University at Shalakan, Kalubia Governorate, Egypt, to evaluate the effect of two irrigation systems (trickle and modified furrow irrigation) and five maize (M)-cowpea (C) intercropping patterns (sole M-30, sole M-15, ridge ...

Climate change impacts on cowpea productivity in Nigeria ...

African Journals Online (AJOL)

If a climate signal could be detected at state or regional level, it would be useful to policy planners, agricultural authority and farmers to prepare for climate change. This study, therefore, employed a statistical model to investigate the relationship between the yield of cowpea and temperature (in centigrade) and precipitation ...

Estimation of dinitrogen fixation by cowpea (Vigna unguiculata) using residual soil 15N in poppy (Papaver somniferum L) cowpea sequence

International Nuclear Information System (INIS)

Patra, D.D.; Chand, Sukhmal; Anwar, M.

1994-01-01

Estimation of dinitrogen fixation by cowpea was carried out under greenhouse conditions using pots each containing 12 kg soil. Different 15 N sources included residual soil 15 N where urea was applied to opium poppy before planting of cowpea as fixing and maize as non-fixing crop. Other N sources were labelled urea, 15 N labelled poppy straw, and labelled urea + unlabelled poppy straw. The amount of N 2 fixed varied with the source of 15 N in soil. Plant material treatment gave a higher estimate at 40 days, whereas the estimate was highest with residual 15 N at 75 days. Such variation is attributed to variation in 1 5N enrichment which can be reduced by utilizing the residual 15 N which gives a more stable enrichment of soil 15 N with time. It may also alleviate the errors resulting from the differential pattern of 15 N uptake by fixing and nonfixing plant due to temporal variation in 15 N enrichment in soil. (author). 8 refs., 3 tabs

interactive effect of cowpea variety, dose and exposure time

African Journals Online (AJOL)

ACSS

variety (V), exposure time (T) and dose (D) on the tolerance of C. maculatus to both plant materials. The effect ... laboratories and institutions of higher education in several West .... Each value is the mean±S.E of 20 cowpea seeds. Means ...

Study on transformation of cowpea trypsin inhibitor gene into ...

African Journals Online (AJOL)

Cowpea Trypsin Inhibitor (CpTI) gene was transferred into cauliflower by agrobacterium-mediated transformation method, and 14 transgenic cauliflower plants were obtained. Cotyledons and hypocotyls were used as explants. The putative transformants were assayed by PCR and Southern blotting analysis. The results ...

Analysis of pre- and post-harvest practices of cowpea ( Vigna ...

African Journals Online (AJOL)

International Journal of Biological and Chemical Sciences ... Practices such as farming and storage conditions may influence the production ... Cowpea infestation by insects on farm and in storage was a major problem mentioned by farmers.

Recent characterization of cowpea aphid-borne mosaic virus ...

African Journals Online (AJOL)

Woodiness disease is the most important disorder of passion fruit worldwide. The causal agent in Brazil is the Cowpea aphid-borne mosaic virus (CABMV), and despite the economic relevance of passion fruit for agriculture there have been recently very few studies about this virus in Brazil and worldwide. This work reveals ...

Spectrophotometric versus NIR-MIR assessments of cowpea pods for discriminating the impact of freezing.

Science.gov (United States)

Machado, Nelson; Domínguez-Perles, Raúl; Ramos, Ana; Rosa, Eduardo As; Barros, Ana Irna

2017-10-01

Freezing represents an important storage method for vegetal foodstuffs, such as cowpea pods, and thus the impact of this process on the chemical composition of these matrices arises as a prominent issue. In this sense, the phytochemical contents in frozen cowpea pods (i.e. at 6 and 9 months) have been compared with fresh cowpea pods material, with the samples being concomitantly assessed by Fourier-transform infrared spectroscopy (FTIR), both mid-infrared (MIR) and near infrared (NIR), aiming to evaluate the potential of these techniques as a rapid tool for the traceability of these matrices. A decrease in phytochemical contents during freezing was observed, allowing the classification of samples according to the freezing period based on such variations. Also, MIR and NIR allowed discrimination of samples: the use of the first derivative demonstrated a better performance for this purpose, whereas the use of the normalized spectra gave the best correlations between the spectra and specific contents. In both cases, NIR displayed the best performance. Freezing of cowpea pods leads to a decrease of phytochemical contents, which can be monitored by FTIR spectroscopy, both within the MIR and NIR ranges, whereas the use of this technique, in tandem with chemometrics, constitutes a suitable methodology for the traceability of these matrices. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Active aggregation among sexes in bean flower thrips (Megalurothrips sjostedti) on cowpea (Vigna unguiculata).

Science.gov (United States)

Niassy, Saliou; Ekesi, Sunday; Maniania, Nguya K; Orindi, Benedict; Moritz, Gerald B; de Kogel, Willem J; Subramanian, Sevgan

2016-01-01

Male sexual aggregations are a common territorial, mating-related or resource-based, behaviour observed in diverse organisms, including insects such as thrips. The influence of factors such as plant substrate, time of day, and geographic location on aggregation of thrips is uncertain, therefore we monitored the dispersion of male and female bean flower thrips (BFT), Megalurothrips sjostedti (Trybom) (Thysanoptera: Thripidae), on cowpea, Vigna unguiculata (L.) Walp. (Fabaceae), over three cowpea growth stages and across three cowpea-growing areas of Kenya. Our results indicated that for all the crop growth stages, the density of BFTs varied over the time of day, with higher densities at 10:00, 13:00, and 16:00 hours than at 07:00 hours. Thrips densities did not differ among blocks at the budding stage, but they did at peak flowering and podding stages. Dispersion indices suggested that both male and female BFTs were aggregated. Active male aggregation occurred only on green plant parts and it varied across blocks, crop stages, and locations. Similarly, active female aggregation was observed in peak flowering and podding stages. Such active aggregation indicates a semiochemical or behaviour-mediated aggregation. Identification of such a semiochemical may offer new opportunities for refining monitoring and management strategies for BFT on cowpea, the most important grain legume in sub-Saharan Africa.

The ability of rhizobacteria to solubilize phosphate and synthesize of indoleacetic acid in cowpea

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Weslany Silva Rocha

2018-01-01

Full Text Available The Cerrado comprises a vast ecoregion in central Brazil where plants show both growth and nitrogen fixation deficiencies due to low soil fertility. Farmers may overcome such problem using species of microorganisms capable of improving soil fertility such as the Rhizobia bacteria. This work aimed to assess the ability of phosphate solubilization and synthesis of indoleacetic acid (IAA of Rhizobium isolates obtained from Cerrado soils in the state of Tocantins, Brazil, evaluating their symbiotic efficiency in cowpea (Vigna unguiculata L. Walp. plants. We used a total of 32 isolates (or strains of Rhizobium and a reference species of Bradyrhizobium. The capacity of phosphate solubilization and synthesis of IAA was evaluated in vitro, while the symbiotic function of rhizobia isolates and the effect on cowpea biomass was assessed in a greenhouse. Only eight strains were able to solubilize calcium phosphate, while all isolates produced IAA. The rhizobia inoculation caused a significant increase in biomass and nodulation of cowpea. The isolates UFT R122 and UFT R124 stood out with the highest values for the studied parameters, showing rises above 33% of relative efficiency in comparison to the treatment with nitrogen fertilization. By associating the results of phosphate solubilization capacity, IAA synthesis, symbiotic ability, and nodulation, we conclude that the isolates that showed good performance are potential inoculants for cowpea in Cerrado soils.

First report of root rot of cowpea caused by Fusarium equiseti in Georgia in the United States

Science.gov (United States)

Root rot was observed on cowpea in Tift County, Georgia, in May of 2015. The disease occurred on approximately 10% of cowpea plants in 2 fields (2 ha). Symptoms appeared as sunken reddish brown lesions on roots and stems under the soil line, secondary roots became dark brown and rotted, and infected...

survey of the symptoms and viruses associated with cowpea (vigna

African Journals Online (AJOL)

Osondu

2012-10-29

Oct 29, 2012 ... of the prevalence of virus disease symptoms and to specifically identify the viruses infecting cowpea. (Vigna unguiculata . ... 1Department of Crop Protection, Faculty of Agriculture,. University of ..... emerging viruses. This will ...

Effects of feeding different levels of cowpea (Vigna unguiculata) on ...

African Journals Online (AJOL)

glucose by the hexokinase method (Gemeni, ENI Company). Total protein was ... compared by an 8 by 2 chi-square contingency test, using sin- .... small intestinal morphology caused by feeding cowpea diet ... Similar views were documented.

Inheritance of Early Maturity in Some Cowpea (Vigna unguiculata (L. Walp. Genotypes under Rain Fed Conditions in Northern Ghana

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Emmanuel Yaw Owusu

2018-01-01

Full Text Available A field experiment was conducted at Savanna Agricultural Research Institute in 2015 cropping season to examine the inheritance of early maturity among an extra-early maturing landrace Sanzi and a medium maturing variety Padi-Tuya and their progenies. The results indicated highly significant (P0.05 were observed between F1 and RF1, implying absence of maternal effect. The segregation ratio in the F2 population for early and medium maturity fitted into the ratio 3 : 1, indicating single dominant gene mode of inheritance. Significant positive correlations were found between DNPM, DFFI, DFF, and DFPM; hence selection criteria to improve early maturity of cowpea should focus on these traits. Grain yield also had significant positive correlations with maturity indices indicating high grain yield is associated with late maturity; therefore, high grain yield should be considered alongside early maturity when selecting progenies for earliness.

Spectroscopy on the assembly of cowpea chlorotic mottle virus

NARCIS (Netherlands)

Kruese, J.

1979-01-01

This thesis describes the characterization of cowpea chlorotic mottle virus (CCMV) by using spectroscopic techniques. In chapter one and two the main properties of CCMV, which belongs to the bromoviruses, are summarized. The application of spectroscopic techniques in the study of other viruses is

Increased heavy metal tolerance of cowpea plants by dual ...

African Journals Online (AJOL)

Through biological inoculation technology, the bacterial-mycorrhizal-legume tripartite symbiosis in artificially heavy metal polluted soil was documented and the effects of dual inoculation with arbuscular mycorrhizal (AM) fungus and Rhizobium (N-fixing bacteria, NFB) on the host plant cowpea (Vigna sinensis) in pot ...

Nitrogen symbiotically fixed by cowpea and gliricidia in traditional and agroforestry systems under semiarid conditions

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Júlio César Rodrigues Martins

2015-02-01

Full Text Available The objective of this work was to estimate the amounts of N fixed by cowpea in a traditional system and by cowpea and gliricidia in an agroforestry system in the Brazilian Northeast semiarid. The experiment was carried out in a randomized complete block design, in a split-plot arrangement, with four replicates, in the semiarid region of the state of Paraíba, Brazil. Plots consisted of agroforestry and traditional systems (no trees, and split-plots of the three crops planted between the tree rows in the agroforestry system. To estimate N fixation, plant samples were collected in the fourth growth cycle of the perennial species and in the fourth planting cycle of the annual species. In the agroforestry system with buffel grass and prickly-pear cactus, gliricidia plants symbiotically fix high proportions of N (>50% and contribute with higher N amounts (40 kg ha-1 in leaves than in the traditional system (11 kg ha-1 in grain and 18 kg ha-1 in straw. In the agroforestry system with maize and cowpea, gliricidia plants do not fix nitrogen, and N input is limited to the fixation by cowpea (2.7 kg ha-1, which is lower than in the traditional system due to its lower biomass production.

Identifying yield-optimizing environments for two cowpea breeding lines by manipulating photoperiod and harvest scenario

Science.gov (United States)

Ohler, T. A.; Mitchell, C. A.

1996-01-01

Photoperiod and harvest scenario of cowpea (Vigna unguiculata L. Walp) canopies were manipulated to optimize productivity for use in future controlled ecological life-support systems. Productivity was measured by edible yield rate (EYR:g m-2 day-1), shoot harvest index (SHI: g edible biomass [g total shoot dry weight]), and yield-efficiency rate (YER:g edible biomass m-2 day-1 per[g nonedible shoot dry weight]). Breeding lines 'IT84S-2246' (S-2246) and "IT82D-889' (D-889) were grown in a greenhouse under 8-, 12-, or 24-h photoperiods. S-2246 was short-day and D-889 was day-neutral for flowering. Under each photoperiod, cowpeas were harvested either for leaves only, seeds only, or leaves plus seeds (mixed harvest). Photoperiod did not affect EYR of either breeding line for any harvest scenario tested. Averaged over both breeding lines, seed harvest gave the highest EYR at 6.7 g m-2 day-1. The highest SHI (65%) and YER (94 mg m-2 day-1 g-1) were achieved for leaf-only harvest of D-889 under an 8-h photoperiod. For leaf-only harvest of S-2246, both SHI and YER increased with increasing photoperiod, but declined for seed-only and mixed harvests. However, photoperiod had no effect on SHI or YER for D-889 for any harvest scenario. A second experiment utilized the short-day cowpea breeding line 'IT89KD-288' (D-288) and the day-neutral breeding line 'IT87D-941-1' (D-941) to compare yield parameters using photoperiod extension under differing lamp types. This experiment confirmed the photoperiod responses of D-889 and S-2246 to a mixed-harvest scenario and indicated that daylength extension with higher irradiance from high pressure sodium lamps further suppressed EYR, SHI, and YER of the short-day breeding line D-288.

Complementary feeding with cowpea reduces growth faltering in rural Malawian infants: a blind, randomized controlled clinical trial.

Science.gov (United States)

Stephenson, Kevin B; Agapova, Sophia E; Divala, Oscar; Kaimila, Yankho; Maleta, Kenneth M; Thakwalakwa, Chrissie; Ordiz, M Isabel; Trehan, Indi; Manary, Mark J

2017-12-01

Background: Growth faltering is common in rural African children and is attributed to inadequate dietary intake and environmental enteric dysfunction (EED). Objective: We tested the hypothesis that complementary feeding with cowpea or common bean flour would reduce growth faltering and EED in 6-mo-old rural Malawians compared with the control group receiving a corn-soy blend. Design: A prospective, double-blind, randomized controlled clinical trial was conducted in which children received daily feeding for 6 mo (200 kcal/d when 6-9 mo old and 300 kcal/d when 10-12 mo old). The primary outcomes were change in length-for-age z score (LAZ) and improvements in EED, as measured by percentage of lactulose excretion (%L). %L Cowpea and common bean added 4.6-5.2 g protein/d and 4-5 g indigestible carbohydrate/d to the diet. LAZ and weight-for-height z score were reduced in all 3 groups from 6 to 12 mo of age. The changes in LAZ [mean (95% CI)] for the cowpea, common bean, and control groups from 6 to 9 mo were -0.14 (-0.24, -0.04), -0.27 (-0.38, -0.16), and -0.27 (-0.35, -0.19), respectively. LAZ was reduced less in infants receiving cowpea than in those receiving control food from 6 to 9 mo ( P = 0.048). The absolute value of %L did not differ between the dietary groups at 9 mo of age (mean ± SD: 0.30 ± 0.43, 0.23 ± 0.21, and 0.26 ± 0.31 for cowpea, common bean, and control, respectively), nor did the change in %L from 6 to 9 mo. Conclusion: Addition of cowpea to complementary feeding in Malawian infants resulted in less linear growth faltering. This trial was registered at clinicaltrials.gov as NCT02472262. © 2017 American Society for Nutrition.

Effect of rotation of cowpea (Vigna unguiculata) with fonio (Digitaria exilis) and millet (Pennisetum glaucum) on Macrophomina phaseolina densities and cowpea yield

NARCIS (Netherlands)

Ndiaye, M.; Termorshuizen, A.J.; Bruggen, van A.H.C.

2008-01-01

Macrophomina phaseolina, the causal agent of charcoal rot, causes great damage to cowpea in the Sahel. One of the few options to manage the disease is by cropping nonhosts that may reduce the soil inoculum below a damage threshold level. To test this, fonio (Digitaria exilis) and millet (Pennisetum

Genetic diversity and population structure analysis of accessions in the Chinese cowpea [Vigna unguiculata (L.) Walp.] germplasm collection

Science.gov (United States)

Cowpea (Vigna unguiculata) is an important legume crop with diverse uses. The species is presently a minor crop, and evaluation of its genetic diversity has been very limited. In this study, a total of 200 genic and 100 genomic simple sequence repeat (SSR) markers were developed from cowpea unigene ...

Purification and properties of cowpea mosaic virus RNA replicase

NARCIS (Netherlands)

Zabel, P.

1978-01-01

This thesis concerns the partial purification and properties of an RNA-dependent RNA polymerase (RNA replicase) produced upon infection of Vigna unguiculata plants with Cowpea Mosaic Virus (CPMV). The enzyme is believed to be coded, at least in part, by the virus genome and to

Effectiveness and efficiency of chemical mutagens in cowpea (Vigna ...

African Journals Online (AJOL)

STORAGESEVER

2008-11-19

Nov 19, 2008 ... A study was undertaken in a cowpea (Vigna unguiculata (L.) Walp.) variety CO 6 to assess the efficiency and effectiveness of chemical mutagens; ethyl methane sulphonate (EMS), diethyl sulphate (DES) and sodium azide (SA). EMS treatments were found highly effective than the other chemicals.

Management of foliar and soilborne pathogens of cowpea ( Vigna ...

African Journals Online (AJOL)

White and pink garlic extracts were tested for their antifungal potentials on mycelial radial growth, spores and sclerotial production of Macrophomina phaseolina (Tassi) Goid, Colletotrichum destructivum O gara and Colletotrichum capsici (Syd) Butler and Bisby pathogens of cowpea in vitro. Water or ethanol extracts of ...

Characterization of cowpea chlorotic mottle virus and its assembly

NARCIS (Netherlands)

Verduin, B.J.M.

1978-01-01

This thesis decribes the conditions for isolation of cowpea chlorotic mottle virus (CCMV), its ribonucleic acid (RNA) and the coat protein, the characterization of the virus and its constituents (chapter 3, 4 and 5) and the dissociation and assembly behaviour of the virus (chapter 6 and

Performance of polymer compositions as carrier to cowpea rhizobial ...

African Journals Online (AJOL)

... was to evaluate inoculant formulations to cowpea (Vigna unguiculata L. Walp) containing polymers as carrier materials and rhizobial strains. To assess the efficiency of the new inoculants formulations, the rhizobial survival in inoculated and stored seeds and the field performance of a selected formulation were evaluated.

Integrated management of cowpea insect pests using elite cultivars ...

African Journals Online (AJOL)

Cowpea planted in June flowered and podded between early to mid-August when post-flowering pests (M. vitrata, M. sjostedti and Clarigralla tomentosicollis) densities were relatively low and produced significantly higher grain yields without insecticide protection compared to other planting dates. The flowering and pod ...

Graphical assessment of yield stability and adaptation in cowpeas ...

African Journals Online (AJOL)

Graphical assessment of yield stability and adaptation in cowpeas (Vigna unguiculata (L) Walp). DK Ojo, MS Oduola, OA Oduwaye. Abstract. No Abstract. Nigerian Journal of Genetics Vol. 20 2006: pp. 17-25. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

Management of Seed-Borne Fungi in Cowpea Using Leaf Extracts ...

African Journals Online (AJOL)

PROF HORSFALL

2018-04-15

Apr 15, 2018 ... Management of Seed-Borne Fungi in Cowpea Using Leaf Extracts and Sodium. Bicarbonate ... is regarded as the most essential legume crop for poor people in ..... legumes and oil seeds of Nigeria: Principles of. Production ...

Effect of "6"0Co-induced gamma radiation exposure and Jasmonic acid on antioxidant responses in Cowpea varieties

International Nuclear Information System (INIS)

Shukla, Pradeep Kumar; Bhagoji, Ravi; Ramteke, P.W.; Misra, Pragati; Maurice, Navodita

2017-01-01

Cowpea used to be the first crop harvested before the cereal crops are ready and therefore is referred to as 'hungry-season crop'. The gamma irradiation is known to increase nutritional values of food sources and also enhance and accelerate growth of certain vegetables Antioxidants are the metabolites, produced by the plant in response to different stress conditions e.g. radiation stress etc. Seeds of four cowpea varieties were treated with different doses of gamma radiation and effect of jasmonic acid (JA) on antioxidant response of cowpea was studied. The results showed that there was no linear correlation between application of JA and different antioxidant contents. (author)

Dry matter content and fruit size affect flavour and texture of novel Actinidia deliciosa genotypes.

Science.gov (United States)

Nardozza, Simona; Gamble, Joanna; Axten, Lauren G; Wohlers, Mark W; Clearwater, Michael J; Feng, Jinquan; Harker, F Roger

2011-03-15

Previous studies with commercial kiwifruit cultivars have demonstrated that the taste of fruit with higher dry matter content (DM) is more liked by consumers. A unique replicated trial of kiwifruit genotypes (10 high/low DM × small/large-fruited genotypes) has provided an opportunity to consider how the genetic propensity for a kiwifruit to accumulate DM affects fruit flavour and texture. In the present study, eating-ripe fruit from each of the genotypes were assessed using a trained sensory panel and the relationships between these sensory attributes and fresh weight, DM, flesh firmness and soluble solids content (SSC) were explored. The genotypes provided a diversity of flavour and texture attributes, each of which varied in perceived intensity of the sensory experience. High-DM genotypes had higher SSC and were perceived as sweeter than low-DM genotypes. Sweet taste was closely associated with the perception of the tropical flavour and high-DM genotypes were found to have more tropical notes. Fruit size was associated with fruit texture, and small fruit were characterised by a firmer and more fibrous core. Large high-DM fruit were perceived as juicier than those of all other genotypes. Genotypes were perceived differently from one another, and differences in fruit size and DM content were reflected in fruit sensorial properties. This study is unique in demonstrating interactions between fruit size, DM and sensory properties. These findings could be relevant not only to kiwifruit but to fruiting crop breeders in general, because of the demonstrated potential for effects of fruit size and DM content on sweetness, flavour and fruit texture. Copyright © 2010 Society of Chemical Industry.

Economietric analysis of cowpea production in the north-eastern ...

African Journals Online (AJOL)

Economietric analysis of cowpea production in the north-eastern part of Adamawa State, Nigeria. J Stephen, SI Mshelia. Abstract. No Abstract. Global Journal of Agricultural Sciences Vol. 7 (1) 2008: pp.127-130. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL ...

Nucleotide sequences from the genomes of diverse cowpea accessions for discovery of genetic variation as part of the Feed the Future Innovation Lab for Climate Resilient Cowpea

Data.gov (United States)

US Agency for International Development — Nucleotide sequences were generated from 37 cowpea (Vigna unguiculata L. Walp.) accessions relevant to Africa, China and the USA to discover at type of genetic...

QTL mapping and transcriptome analysis of cowpea reveals candidate genes for root-knot nematode resistance.

Science.gov (United States)

Santos, Jansen Rodrigo Pereira; Ndeve, Arsenio Daniel; Huynh, Bao-Lam; Matthews, William Charles; Roberts, Philip Alan

2018-01-01

Cowpea is one of the most important food and forage legumes in drier regions of the tropics and subtropics. However, cowpea yield worldwide is markedly below the known potential due to abiotic and biotic stresses, including parasitism by root-knot nematodes (Meloidogyne spp., RKN). Two resistance genes with dominant effect, Rk and Rk2, have been reported to provide resistance against RKN in cowpea. Despite their description and use in breeding for resistance to RKN and particularly genetic mapping of the Rk locus, the exact genes conferring resistance to RKN remain unknown. In the present work, QTL mapping using recombinant inbred line (RIL) population 524B x IT84S-2049 segregating for a newly mapped locus and analysis of the transcriptome changes in two cowpea near-isogenic lines (NIL) were used to identify candidate genes for Rk and the newly mapped locus. A major QTL, designated QRk-vu9.1, associated with resistance to Meloidogyne javanica reproduction, was detected and mapped on linkage group LG9 at position 13.37 cM using egg production data. Transcriptome analysis on resistant and susceptible NILs 3 and 9 days after inoculation revealed up-regulation of 109 and 98 genes and down-regulation of 110 and 89 genes, respectively, out of 19,922 unique genes mapped to the common bean reference genome. Among the differentially expressed genes, four and nine genes were found within the QRk-vu9.1 and QRk-vu11.1 QTL intervals, respectively. Six of these genes belong to the TIR-NBS-LRR family of resistance genes and three were upregulated at one or more time-points. Quantitative RT-PCR validated gene expression to be positively correlated with RNA-seq expression pattern for eight genes. Future functional analysis of these cowpea genes will enhance our understanding of Rk-mediated resistance and identify the specific gene responsible for the resistance.

Uniformidade de sementes de genótipos de feijão-caupi cultivados em dois ambientes no Estado de Roraima. = Seeds uniformity from cowpea genotypes cultivated in two environments of the State of Roraima.

Directory of Open Access Journals (Sweden)

Katherine Rodrigues Arruda

2009-06-01

Full Text Available - Objetivou-se com o presente trabalho avaliar a uniformidade de sementes de 19 genótipos de feijão-caupi cultivados em dois ambientes no Estado de Roraima. Foram utilizadas sementes produzidas nos Campos Experimentais Serra da Prata (CESP e do Monte Cristo (CEMC pertencentes a Embrapa Roraima, produzidas durante o ano de 2008. Amostras de 400 g de sementes de feijão-caupi foram separadas e pesadas. Após a pesagem, cada amostra foi classifi cada por cinco peneiras de crivos redondos e oblongos de diferentes dimensões. As sementes retidas em cada peneira foram pesadas separadamente. Sementes da maior porção foram avaliadas quanto a massa de mil sementes e germinação. Na análise dos resultados de uniformidade verificou-se que 89,5% das sementes produzidas no CEMC são maiores que 4,5 x 22 mm e no CESP 90,0%. Quanto a massa média de mil sementes não se verifica diferenças entre os dois ambientes, e entre os materiais variação de 127,5 a 219,6 g. As sementes do CESP apresentam qualidade fisiológica superior as do CEMC. = The objective of this study was to evaluated the uniformity of seeds from 19 cowpea genotypes in two environment of Roraima State. The seeds utilized were produced in the experimental fields of Serra da Prata (CESP and Monte Cristo (CEMC, belonging to Embrapa Roraima. Samples of 400 g of cowpea seeds were separated and weighed and classified by five sieves with round and oblong holes of different dimensions, being weighed separately. Seeds retained in each sieve were weighed separately. Seeds withheld in 4.5 x 22 mm sieve were assessed according to mass of a thousand seeds and germination. Results showed that 89.5 % of seeds produced in CEMC are bigger than 4.5 x 22 mm and in CESP 9 0.0%. Concerning to average mass of a thousand seeds, no differences were verified between the two environments, while materials ranged from 127.5 to 219.6 g. Seeds of CESP showed physiological quality superior than CEMC.

BIOCHAR AS SOIL CONDITIONER IN THE SUCCESSION OF UPLAND RICE AND COWPEA FERTILIZED WITH NITROGEN

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NEYTON DE OLIVEIRA MIRANDA

2017-01-01

Full Text Available The effects of biochar and nitrogen application on yields of upland rice and cowpea and on soil fertility were determined in a greenhouse in Macaíba, RN, Brazil. The trial consisted of the succession of two crops in a completely randomized design and a factorial scheme, with four replicates. Initially, four doses of biochar and four doses of nitrogen were tested for cultivation of rice. Subsequently, four doses of biochar and two doses of nitrogen were tested in half of the pots maintained for planting cowpea. Soil was sampled after rice harvest for half of the pots and at end of the trial for the remaining pots. We evaluated the following parameters: mass of hundred grains of rice, dry shoot mass, panicle number, number of filled spikelets and of empty spikelets, and grain production. Determinations for cowpea were: pod number per pot, grain number per pod, and grain production per pot. Measured soil parameters were: pH, contents of organic carbon, P, K, Ca, Mg, Na, cation exchange capacity, and exchangeable sodium percentage. Biochar addition did not influence yield components of upland rice and cowpea, but resulted in increased soil N retention, which influenced rice dry shoot mass, spikelets sterility, panicle number, and grain mass. Biochar also promoted increased soil pH, potassium content, and exchangeable sodium percentage and decreased calcium and magnesium concentrations.

Evaluation of Growth and Species Composition of Weeds in Maize-Cowpea Intercropping based on Additive Series under Organic Farming Condition

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Hamdollah Eskandari

2016-11-01

relative yield total (RYT index. Weed smothering efficiency (WSE was used to evaluate the effect of intercropping on reducing weeds the dry weight. Results and discussion Results indicated that soil moisture content, PAR interception and soil temperature were affected by cropping patterns. The lowest and highest values of soil temperatures were observed in intercropping and sole crop systems, respectively. Intercropping systems exploited soil water more than sole crops. PAR interception was higher in intercropping compared to sole cropping. However, sole cowpea showed lower PAR interception compared to maize sole crop. Relative yield total (RYT index was more than unity in all intercropping systems. Weed smothering efficiency (WSE showed that dry weight of weeds was reduced by 21-26 and 28-42 percentages in intercropping systems compared to sole maize and sole cowpea cropping systems, respectively. The growth of weeds (in terms of total dry weight in intercropping systems were reduced in which from five recorded weed species, the dry weight of them, including amaranth (Amaranthus retondus L., pigweed (Echinocloa cruss-gali L., purslane (Portulaca oleraceae L. and Halikakabon (Solanum nigrum L. decreased in intercropping compared to sole cropping systems. Intercropping components showed a complementary relation in consuming environmental resources including soil moisture and PAR. Since the soil temperature was lower in intercropping compared to sole cropping, lower soil moisture in intercropping cannot be resulted from higher evaporation in intercropping, but also the widespread root system in intercropping resulted in higher efficiency in soil moisture consuming. Relative yield total more than unity, showing the advantages of intercropping in environmental resources consumption. Soil covering and higher biodiversity are two main factors reducing weeds growth in intercropping because the two recent factors lower PAR availability for weeds which can reduce weed. The current

Adoption of Kerala Agricultural University Recommended Practices of Amaranthus and Vegetable Cowpea

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K.K Anju

2017-04-01

Full Text Available The study was conducted in Thiruvananthapuram district of Kerala. Ninety farmers engaged in commercial cultivation of amaranthus and vegetable cowpea were selected through three stage random sampling procedure. Ten independent variables were selected based on judges’ relevancy rating. Majority of the respondents belonged to medium category with respect to adoption. In the case of amaranthus growers, four variables, namely, contact with extension agency, scientific orientation, innovativeness and mass media exposure were found to be significantly and positively related to adoption. Education, scientific orientation and innovativeness were found to be significantly and positively related to adoption in the case of vegetable cowpea growers.

Determination of some mineral components of cowpea (Vigna unguiculata (L.) Walp) using instrumental neutron activation analysis

International Nuclear Information System (INIS)

Asante, I.K; Acheampong, A.O.; Adu-Dapaah, H.

2007-01-01

Some mineral elements in the seeds of the cowpea were determined using instrumental neutron activation analysis. The cowpea cultivars were made up of improved varieties (Soronko, Gbeho, Ayiyi, Asontem, Asontem1, Bengpla, Asetenapa and Adom), farmers' accessions (87/7, 87/1, 87/27, 87/147, 87/34, 87/49, 87/83, 87/157, 87/149, 87/30, 87/153, 96/046, 87/137, 96/129, BTB 96/091, OAA 96/30, BTB 96/054), and experimental materials (IT870-677-2, Caroni, Kaase Market, 1977 and 1239). A total of 14 elements (Al, Ca, Mg, V, Mn, Br, Cl, K, Na, Zn, Cu, Ta, Si and In) were detected in the seeds of the 30 cowpea cultivars. Five of the elements (Na, K, Mg, Ca and Cl) identified are classified as major elements in the human body, while four (Mn, Zn, V, Si) are trace elements. The major elements K, Na, Ca, Mg and Cl were detected in high concentration in cultivars 96/129, 87/137, Ayiyi, 87/34 and 87/49, respectively. The trace elements Mn, Zn, V, Si, Cu and Al were detected in high concentration in cultivars 87/34, 87/27, 87/34, Bengpla, 87/34 and 87/34, respectively. From the results the following accessions could be selected and incorporated into a cowpea mineral nutritional improvement programme: 96/129, 87/137, Ayiyi, 87/34, 87/49 and 87/27. The presence of the five major elements and the trace elements indicates that cowpea has a rich source of mineral elements and, therefore, can be used to improve the diet of both humans and livestock. (au)

Effect of addition of thermally modified cowpea protein on sensory acceptability and textural properties of wheat bread and sponge cake.

Science.gov (United States)

Campbell, Lydia; Euston, Stephen R; Ahmed, Mohamed A

2016-03-01

This paper investigates the sensory acceptability and textural properties of leavened wheat bread and sponge cake fortified with cow protein isolates that had been denatured and glycated by thermal treatment. Defatted cowpea flour was prepared from cow pea beans and the protein isolate was prepared (CPI) and thermally denatured (DCPI). To prepare glycated cowpea protein isolate (GCPI) the cowpea flour slurry was heat treated before isolation of the protein. CPI was more susceptible to thermal denaturation than GCPI as determined by turbidity and sulphydryl groups resulting in greater loss of solubility. This is attributed to the higher glycation degree and higher carbohydrate content of GCPI as demonstrated by glycoprotein staining of SDS PAGE gels. Water absorption of bread dough was significantly enhanced by DCPI and to a larger extent GCPI compared to the control, resulting in softer texture. CPI resulted in significantly increased crumb hardness in baked bread than the control whereas DCPI or GCPI resulted in significantly softer crumb. Bread fortified with 4% DCPI or GCPI was similar to control as regards sensory and textural properties whereas 4% CPI was significantly different, limiting its inclusion level to 2%. There was a trend for higher sensory acceptability scores for GCPI containing bread compared DCPI. Whole egg was replaced by 20% by GCPI (3.5%) in sponge cake without affecting the sensory acceptability, whereas CPI and DCPI supplemented cakes were significantly different than the control. Copyright © 2015 Elsevier Ltd. All rights reserved.

Population dynamics of Aphis gossypii Glover and in sole and intercropping systems of cotton and cowpea.

Science.gov (United States)

Fernandes, Francisco S; Godoy, Wesley A C; Ramalho, Francisco S; Garcia, Adriano G; Santos, Bárbara D B; Malaquias, José B

2018-01-01

Population dynamics of aphids have been studied in sole and intercropping systems. These studies have required the use of more precise analytical tools in order to better understand patterns in quantitative data. Mathematical models are among the most important tools to explain the dynamics of insect populations. This study investigated the population dynamics of aphids Aphis gossypii and Aphis craccivora over time, using mathematical models composed of a set of differential equations as a helpful analytical tool to understand the population dynamics of aphids in arrangements of cotton and cowpea. The treatments were sole cotton, sole cowpea, and three arrangements of cotton intercropped with cowpea (t1, t2 and t3). The plants were infested with two aphid species and were evaluated at 7, 14, 28, 35, 42, and 49 days after the infestations. Mathematical models were used to fit the population dynamics of two aphid species. There were good fits for aphid dynamics by mathematical model over time. The highest population peak of both species A. gossypii and A. craccivora was found in the sole crops, and the lowest population peak was found in crop system t2. These results are important for integrated management programs of aphids in cotton and cowpea.

Radiation-use efficiency of soybean, mungbean and cowpea under different environmental conditions

International Nuclear Information System (INIS)

Muchow, R.C.; Robertson, M.J.; Pengelly, B.C.

1993-01-01

Radiation-use efficiency (RUE), defined as the amount of biomass accumulated per unit radiation intercepted, is a key measure of the photosynthetic performance of crops growing in different environments. The RUE of soybean (Glycine max L.), mungbean (Vigna radiata) and cowpea (Vigna unguiculata) growing under well-watered field conditions in tropical and subtropical environments was determined from frequent biomass samplings and continous logging of intercepted radiation throughout growth. The slope of the relationship between net biomass accumulation and intercepted radiation was linear throughout most of growth, almost until the end of pod-filling in all species and all environments. The decrease in RUE just prior to maturity was associated with losses of biomass due to leaf shedding, and also with a decline in specific leaf nitrogen. The RUE during the linear phase was slightly higher in cowpea than in mungbean and soybean. For each species, the RUE was similar in different environments despite large differences in air temperature, water vapour saturation deficit and incident radiation. It was concluded that RUE under well-watered conditions is constant throughout most of growth and unaffected by the aerial environment. Baseline values of RUE were 0.88 g MJ -1 for soybean, 0.94 g MJ -1 for mungbean, and 1.05 g MJ -1 for cowpea. (author)

Productive performance of cowpea-radish intercropping under different amounts of rooster tree biomass incorporated into the soil

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Maria F. S. Pereira

Full Text Available ABSTRACT Intercropping systems of cowpea with radish are beginning to be deployed in the semiarid region of Rio Grande do Norte state. The great challenge is to know whether or not there is productive efficiency in these systems when fertilized with organic matter produced by spontaneous species from the ‘Caatinga’ biome. Thus, the aim of this study was to evaluate the productive performance of cowpea-radish intercropping systems under different amounts of rooster tree biomass incorporated into the soil. The study was conducted at the experimental farm Rafael Fernandes, rural zone of Mossoró, RN, in the period from June to September 2013, in an experimental design of randomized blocks with four treatments and five replicates. The treatments consisted of the following amounts of rooster tree biomass incorporated into the soil (10, 25, 40 and 55 t ha-1 on a dry weight basis. The best productive performance of the cowpea-radish intercrop was obtained when the rooster tree biomass amount of 50.01 t ha-1 was incorporated to the soil. The use of rooster tree biomass as green manure is agronomically viable in intercropped systems of cowpea-radish.

Regulatory considerations surrounding the deployment of Bt-expressing cowpea in Africa: Report of the deliberations of an expert panel

Science.gov (United States)

Cowpea (Vigna unguiculata spp. unguiculata) is adapted to the drier agro-ecological zones of West Africa where it is a major source of dietary protein and widely used as a fodder crop. Improving the productivity of cowpea can enhance food availability and security in West Africa. Insect predation -...

Variation in relative water content, proline accumulation and stress gene expression in two cowpea landraces under drought.

Science.gov (United States)

Zegaoui, Zahia; Planchais, Séverine; Cabassa, Cécile; Djebbar, Reda; Abrous Belbachir, Ouzna; Carol, Pierre

2017-11-01

Many landraces of cowpea [Vigna unguiculata (L.) Walp.] are adapted to particular geographical and climatic conditions. Here we describe two landraces grown respectively in arid and temperate areas of Algeria and assess their physiological and molecular responses to drought stress. As expected, when deprived of water cowpea plants lose water over time with a gradual reduction in transpiration rate. The landraces differed in their relative water content (RWC) and whole plant transpiration rate. The landrace from Menia, an arid area, retained more water in adult leaves. Both landraces responded to drought stress at the molecular level by increasing expression of stress-related genes in aerial parts, including proline metabolism genes. Expression of gene(s) encoding proline synthesis enzyme P5CS was up regulated and gene expression of ProDH, a proline catabolism enzyme, was down regulated. Relatively low amounts of proline accumulated in adult leaves with slight differences between the two landraces. During drought stress the most apical part of plants stayed relatively turgid with a high RWC compared to distal parts that wilted. Expression of key stress genes was higher and more proline accumulated at the apex than in distal leaves indicating that cowpea has a non-uniform stress response at the whole plant level. Our study reveals a developmental control of water stress through preferential proline accumulation in the upper tier of the cowpea plant. We also conclude that cowpea landraces display physiological adaptations to water stress suited to the arid and temperate climates in which they are cultivated. Copyright © 2017 Elsevier GmbH. All rights reserved.

Effect of extrusion conditions and lipoxygenase inactivation treatment on the physical and nutritional properties of corn/cowpea (Vigna unguiculata) blends.

Science.gov (United States)

Sosa-Moguel, Odri; Ruiz-Ruiz, Jorge; Martínez-Ayala, Alma; González, Rolando; Drago, Silvina; Betancur-Ancona, David; Chel-Guerrero, Luis

2009-01-01

The influence of lipoxygenase inactivation and extrusion cooking on the physical and nutritional properties of corn/cowpea (Vigna unguiculata) blends was studied. Corn was blended in an 80:15 proportion with cowpea flour treated to inactivate lipoxygenase (CI) or non-inactivated cowpea flour (CNI). Extrusion variables were temperature (150 degrees C, 165 degrees C and 180 degrees C) and moisture (15%, 17% and 19%). Based on their physical properties, the 165 degrees C/15% corn:CNI, and 165 degrees C/15% corn:CI, and 150 degrees C/15% corn:CI blends were chosen for nutritional quality analysis. Extrudate chemical composition indicated high crude protein levels compared with standard corn-based products. With the exception of lysine, essential amino acids content in the three treatments met FAO requirements. Extrusion and lipoxygenase inactivation are promising options for developing corn/cowpea extruded snack products with good physical properties and nutritional quality.

Weed control in cowpea ( Vigna unguiculata (L) Walp) with ...

African Journals Online (AJOL)

Field experiments were conducted between 1994 and 1997 at the University of Ilorin Teaching and Research Farm, Ilorin (8o29`N; 4o35`E), in the southern Guinea savanna agro-ecological zone, to evaluate the efficacy of pre-emergence applications of two imidazolinone-based herbicide mixtures in cowpea (Vigna ...

CRY 1AB trangenic cowpea obtained by nodal electroporation ...

African Journals Online (AJOL)

Electroporation-mediated genetic transformation was used to introduce Cry 1 Ab insecticidal gene into cowpea. Nodal buds were electroporated in planta with a plasmid carrying the Cry 1Ab and antibiotic resistance npt II genes driven by a 35S CaMV promoter. T1 seeds derived from electroporated branches were selected ...

Genetic variability of cultivated cowpea in Benin assessed by ...

African Journals Online (AJOL)

STORAGESEVER

2008-12-17

Dec 17, 2008 ... Res. Crop Evol. 48: 559-566. Mignouna HD, Ng NQ, Ikea J, Thottapilly G (1998). Genetic diversity in cowpea as revealed by random amplified polymorphic DNA. J. Gen. Breed. 52: 151-159. Nei M, Li WH (1979). Mathematical model for studying genetic variation in terms of restriction endonucleases. Proc.

Quality of cowpea seeds treated with chemicals and stored in controlled and uncontrolled temperature and humidity conditions

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Lucicléia Mendes de Oliveira

2015-06-01

Full Text Available The cowpea is a Fabaceae originated in Africa cultivated in the northern and northeastern of Brazil, where stands out as the main source of protein for the population. For the establishment of culture, seeds are treated to control and prevent pest attacks and diseases, can also attach nutrients to the seeds which will be available for plant development. The objective of the research was to evaluate the performance of cowpea seeds treated with chemical products and stored in controlled and uncontrolled temperature and humidity conditions. The following seeds treatments were applied: control (no treatment; micronutrient Comol 118, insecticide thiamethoxam, fipronil and pyraclostrobin+thiophanate-methyl and imidacloprid+thiodicarb were then stored in a cold environment and natural. The assessment of physiological seed quality was made initially and every 45 days through the germination and vigor. Among all products used, the imidacloprid + thiodicarb and fipronil + pyraclostrobin + thiophanate methyl provides stimulating effect on seed performance; seeds treated with thiamethoxam were less affected by storage than the untreated seeds; seeds treated with micronutrients exhibits similar behavior to untreated seeds and storage in a controlled environment better preserves the seed physiological quality.

Influence of farmyard manure on some morphological and biochemical parameters of cowpea (Vigna unguiculata) seedling grown in cadmium-treated soil.

Science.gov (United States)

Asagba, Samuel Ogheneovo; Ezedom, Theresa; Kadiri, Helen

2017-10-01

The present study aims to assess the effects of the two kinds of farmyard manure (poultry and pig manures) as amendments for soil on cadmium (Cd) toxicity in plants using cowpea seedlings as plant model. Cd toxicity was evaluated by assessing the effect of the metal on the growth rate and antioxidant status as well as the ability of the plant to metabolise xenobiotic. There was a significantly (p cowpea seedlings grown in all the treated soils relative to control. Addition of poultry manure to the soil significantly (p cowpea seedlings grown in Cd-treated soil augmented with poultry manure but not in cowpea seedlings in cadmium-treated soil with pig manure amendments. Similarly, augmentation of Cd-treated soil with pig manure did not alter the Cd-induced effect on the levels of superoxide dismutase (SOD) and lipid peroxidation (LPO) in leaf, stem and roots, as SOD remained significantly (p cowpea seedlings grown in Cd-treated soils amended with poultry manure were restored to a level not significantly (p > 0.05) different from control. Like in the case of SOD, the Cd-induced inhibition of the activity of xenobiotic metabolising enzymes, aldehyde oxidase and sulphite oxidase remained significantly (p  0.05) different from control. In conclusion, the findings of the study revealed that supplementation of Cd-treated soils with pig and poultry manures reversed effects of Cd on cowpea seedlings. However, poultry manure was more effective than pig manure in ameliorating the effects of Cd.

Characterization and genetic relatedness among 37 yardlong bean and cowpea accessions based on morphological characters and RAPD analysis

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Vinich Saereeprasert

2007-05-01

Full Text Available Twenty four yardlong bean and 13 cowpea accessions were planted in the field to characterize their morphology and genetic relatedness. A randomized complete block design (RCBD with two replicationswas used. Growth habit, days to flowering, pod color, pod length, number of pods/plant, yield/plant and consumption quality were recorded. The results showed that pod length, number of pods/plant and podyield/plant among 37 accessions were highly significant differerence. Mean pod yield and pod length of 24 yardlong bean accessions were 212.1 g/plant and 48.7 cm, respectively, while mean pod yield and pod lengthof 13 cowpea accessions were 117.4 g/plant and 21.3 cm, respectively. Twenty two yardlong bean accessions exhibited indeterminate growth habit while 10 of 13 cowpea had determinate growth habit and the restsexhibited semi-determinate growth. Genetic variation and relationships among accessions were investigated based on RAPD technique. Total DNA was extracted from young leaf samples of all accessions using CTAB buffer. One hundred and twenty decamer oligonucleotide primers were screened and 5 primers (OPC-06,OPR-12, OPZ-03, OPZ-08, OPZ-13 were chosen for further evaluation. A dendrogram of genetic similarity was constructed based on 23 polymorphic bands obtained from 5 primers using UPGMA in SPSS program,which revealed separate groups between yardlong bean and cowpea. The similarity coefficient among yardlong bean and cowpea accessions ranged from 0.515 to 1.000 and 0.548 to 1.000, respectively.

Cowpea, Common Bean And Mung Bean Radiation Use Efficiency, Light Extinction Coefficient And Radiation Interception In Double Cropping

International Nuclear Information System (INIS)

Alimadadi, A.; Rostamza, M.; Jahansooz, M.R.; Ahmadi, A.; Tavakol Afshari, R.

2006-01-01

Crop growth modeling for forecasting various plant's functions and their contribution to yield, is one of the ways to improve field management. This trial was set up to evaluate radiation use efficiency of mung bean, common bean and cowpea cultivars in a double cropping system. Field experiment was conducted at Research Farm of College of Agriculture, University of Tehran, Karaj. A 4-replicate group balanced block field experiment was set up. Results showed that the differences among three pulses were significant in terms of biomass (p0.05). Cowpea, producing 5876.8 Kg/ha, had the highest yield among the species used in this study. Comparison of grain yield observed in this experiment with mono crop yield potential, showed that cowpea, common bean and mung bean produced 40%, 37% and 58% of their mono crop grain yield potential, respectively. In the late vegetative growth period, cowpea, mung bean and common bean absorbed 90%, 33% and 36% of photosynthetic active radiation, respectively. There was a significant difference among pulses, in terms of their radiation use efficiency and light extinction coefficient (p0.05 and p0.01, respectively). Cowpea, common bean and mung bean had radiation use efficiencies of 0.84, 0.82 and 0.99, g/MJ and light extinction coefficients of 0.605, 0.344 and 0.458, respectively. Results indicated that in some cultivars, when K decreases and LAI increases, LUE might be increased twice

Yields and protein content of two cowpea varieties grown under ...

African Journals Online (AJOL)

PRECIOUS

2010-02-01

Feb 1, 2010 ... cropping systems (sole and intercropping) and cowpea-leaf pruning regimes ... pruning did have consequential effects on the nutritional value of ... and cabbage for direct consumption or eaten as relish ... long history of fertilization (Mpangane et al., 2004). ..... cabbage (Brassica oleracea L.) proteins.

The major economic field diseases of cowpea in the humid agro ...

African Journals Online (AJOL)

STORAGESEVER

2008-12-29

Dec 29, 2008 ... high relative humidity, which correlates with high rainfall .... BThe 18 lines are representative samples of the 71-cowpea lines evaluated showing high, moderate and ... Nigeria has shown that water or alcohol extract of Piper.

23 cowpea for a changing environment in the rainforest of south

African Journals Online (AJOL)

Cowpea adapted and grown in the rainforest ... kg ha-1 with adjusted moisture at 15%. Above ... distributions were done by dividing the range ... several workers. .... *significant at 5% level of probability; **significant at 1% level of probability.

Protein synthesis directed by cowpea mosaic virus RNAs

International Nuclear Information System (INIS)

Stuik, E.

1979-01-01

The thesis concerns the proteins synthesized under direction of Cowpea mosaic virus RNAs. Sufficient radioactive labelling of proteins was achieved when 35 S as sulphate was administered to intact Vigna plants, cultivated in Hoagland solution. The large polypeptides synthesized under direction of B- and M-RNA are probably precursor molecules from which the coat proteins are generated by a mechanism of posttranslational cleavage. (Auth.)

Impact of sucrose contents and cooking time on cowpea prices in Senegal

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Mb.D Faye

2014-07-01

Full Text Available An alternative approach to traditional consumer behaviour and demand theory is characteristics theory, which assumes that a consumer’s utility function is generated by the characteristics, or attributes, that goods and services possess. Instead of a utility being a function of a product, it becomes a function of the attributes provided by these products. In this paper a hedonic pricing model is used to investigate the influence of sucrose level and cooking time on cowpea prices in Senegal.  Cooking time has a significant impact on price only at Tilene market in Dakar, while the sucrose contents tend to provide a premium throughout. Further investigation shows that the local varieties, AW, Matam and Ndiassiw have higher sucrose contents than the other cowpea varieties.

Draft genome sequence of Bradyrhizobium sp. strain BR 3267, an elite strain recommended for cowpea inoculation in Brazil

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Jean Luiz Simões-Araújo

Full Text Available Abstract The strain BR 3267 is a nitrogen-fixing symbiotic bacteria isolated from soil of semi-arid area of Brazilian Northeast using cowpea as the trap plant. This strain is used as commercial inoculant for cowpea and presents high efficient in nitrogen fixation as consequence of its adaptation potential to semi-arid conditions. We report here the draft genome sequence of Bradyrhizobium sp. strain BR 3267, an elite bacterium used as inoculant for cowpea. Whole genome sequencing of BR 3267 using Illumina MiSeq sequencing technology has 55 scaffolds with a total genome size of 7,904,309 bp and C+G 63%. Annotation was added by the RAST prokaryotic genome annotation service and has shown 7314 coding sequences and 52 RNA genes.

Transcriptional profiling of root-knot nematode induced feeding sites in cowpea (Vigna unguiculata L. Walp. using a soybean genome array

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Das Sayan

2010-08-01

Full Text Available Abstract Background The locus Rk confers resistance against several species of root-knot nematodes (Meloidogyne spp., RKN in cowpea (Vigna unguiculata. Based on histological and reactive oxygen species (ROS profiles, Rk confers a delayed but strong resistance mechanism without a hypersensitive reaction-mediated cell death process, which allows nematode development but blocks reproduction. Results Responses to M. incognita infection in roots of resistant genotype CB46 and a susceptible near-isogenic line (null-Rk were investigated using a soybean Affymetrix GeneChip expression array at 3 and 9 days post-inoculation (dpi. At 9 dpi 552 genes were differentially expressed in incompatible interactions (infected resistant tissue compared with non-infected resistant tissue and 1,060 genes were differentially expressed in compatible interactions (infected susceptible tissue compared with non-infected susceptible tissue. At 3 dpi the differentially expressed genes were 746 for the incompatible and 623 for the compatible interactions. When expression between infected resistant and susceptible genotypes was compared, 638 and 197 genes were differentially expressed at 9 and 3 dpi, respectively. Conclusions In comparing the differentially expressed genes in response to nematode infection, a greater number and proportion of genes were down-regulated in the resistant than in the susceptible genotype, whereas more genes were up-regulated in the susceptible than in the resistant genotype. Gene ontology based functional categorization revealed that the typical defense response was partially suppressed in resistant roots, even at 9 dpi, allowing nematode juvenile development. Differences in ROS concentrations, induction of toxins and other defense related genes seem to play a role in this unique resistance mechanism.

Affective neural responses modulated by serotonin transporter genotype in clinical anxiety and depression.

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Desmond J Oathes

Full Text Available Serotonin transporter gene variants are known to interact with stressful life experiences to increase chances of developing affective symptoms, and these same variants have been shown to influence amygdala reactivity to affective stimuli in non-psychiatric populations. The impact of these gene variants on affective neurocircuitry in anxiety and mood disorders has been studied less extensively. Utilizing a triallelic assay (5-HTTLPR and rs25531 to assess genetic variation linked with altered serotonin signaling, this fMRI study investigated genetic influences on amygdala and anterior insula activity in 50 generalized anxiety disorder patients, 26 of whom also met DSM-IV criteria for social anxiety disorder and/or major depressive disorder, and 39 healthy comparison subjects. A Group x Genotype interaction was observed for both the amygdala and anterior insula in a paradigm designed to elicit responses in these brain areas during the anticipation of and response to aversive pictures. Patients who are S/L(G carriers showed less activity than their L(A/L(A counterparts in both regions and less activity than S/L(G healthy comparison subjects in the amygdala. Moreover, patients with greater insula responses reported higher levels of intolerance of uncertainty, an association that was particularly pronounced for patients with two LA alleles. A genotype effect was not established in healthy controls. These findings link the serotonin transporter gene to affective circuitry findings in anxiety and depression psychopathology and further suggest that its impact on patients may be different from effects typically observed in healthy populations.

Consumer preference for cowpea in Kwara State, Nigeria | Ayinde ...

African Journals Online (AJOL)

The primary data were collected through a structured from 120 respondents and secondary data was used to determine the factors for variation in prices of cowpea. The study revealed that consumers prefer that is of medium size, red in colour, very sweet in taste and a shelf-life of at least month. It also showed that the most ...

Resistance source to cowpea aphid (Aphis craccivora Koch) in ...

African Journals Online (AJOL)

STORAGESEVER

2008-07-18

Jul 18, 2008 ... The present study evaluated the resistance of 7 varieties of the broad bean Vicia faba L. to cowpea aphid, Aphis craccivora Koch, 1854. These landraces from the region of Biskra (in the south of Algeria) were selected in an initial field trial and subjected to further testing in the greenhouse. Landrace V51.

A Single Nucleotide Polymorphism (SNP)-based association analysis for plant growth habit in worldwide Cowpea (Vigna unguiculata (L.) Walp) germplasm

Science.gov (United States)

Cowpea is a legume widely grown in Africa, North, Central and South America, and Asia. The Cowpea plant growth habits consist of erect, semi-prostrate, and prostrate types. Developing a cultivar while considering plant growth habit is essential within a breeding program since the need for a particul...

A study on zinc distribution in calcareous soils for cowpea (Vigna Unguiculata L.) and barely ( Hordeum Vulgare L.)

Science.gov (United States)

Boroomand, Naser; Maleki, Mohammad Reza

2010-05-01

Compared to other cereals, such as wheat and barley cultivars which have low sensitivity to Zn deficiency, cowpea is sensitive to zinc (Zn) deficiency, however it extensively grows even in soils with deficient in Zn. A 8-week greenhouse experiment was conducted to study the response of cowpea and barely to Zn in calcareous soils with different DTPA- Zn. The soil samples were taken from soil surface up to 0.3 m in which their DTPA- Zn ranged from 0.5 to 3.5 mg kg-1. Shoot dry matter, concentration and uptake of Zn were found to be significantly correlated with soil DTPA- Zn in cowpea and barely. Critical deficiency level of Zn in cowpea was 1.3 mg kg-1 in soil and 28.5 mg kg-1 in shoot dry matter, however, to barely symptoms of Zn deficiency was not observed and concentration of Zn was higher than the critical level reported in literatures. Organic carbon (OC), calcium carbonate equivalent (CCE), pH and field capacity soil moisture content(FC) were significantly correlated with plant responses to Zn which were the most influenced characteristics to Zn uptake by plants.

QTL mapping and transcriptome analysis of cowpea reveals candidate genes for root-knot nematode resistance.

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Jansen Rodrigo Pereira Santos

Full Text Available Cowpea is one of the most important food and forage legumes in drier regions of the tropics and subtropics. However, cowpea yield worldwide is markedly below the known potential due to abiotic and biotic stresses, including parasitism by root-knot nematodes (Meloidogyne spp., RKN. Two resistance genes with dominant effect, Rk and Rk2, have been reported to provide resistance against RKN in cowpea. Despite their description and use in breeding for resistance to RKN and particularly genetic mapping of the Rk locus, the exact genes conferring resistance to RKN remain unknown. In the present work, QTL mapping using recombinant inbred line (RIL population 524B x IT84S-2049 segregating for a newly mapped locus and analysis of the transcriptome changes in two cowpea near-isogenic lines (NIL were used to identify candidate genes for Rk and the newly mapped locus. A major QTL, designated QRk-vu9.1, associated with resistance to Meloidogyne javanica reproduction, was detected and mapped on linkage group LG9 at position 13.37 cM using egg production data. Transcriptome analysis on resistant and susceptible NILs 3 and 9 days after inoculation revealed up-regulation of 109 and 98 genes and down-regulation of 110 and 89 genes, respectively, out of 19,922 unique genes mapped to the common bean reference genome. Among the differentially expressed genes, four and nine genes were found within the QRk-vu9.1 and QRk-vu11.1 QTL intervals, respectively. Six of these genes belong to the TIR-NBS-LRR family of resistance genes and three were upregulated at one or more time-points. Quantitative RT-PCR validated gene expression to be positively correlated with RNA-seq expression pattern for eight genes. Future functional analysis of these cowpea genes will enhance our understanding of Rk-mediated resistance and identify the specific gene responsible for the resistance.

Sprouting characteristics and associated changes in nutritional composition of cowpea (Vigna unguiculata).

Science.gov (United States)

Devi, Chingakham Basanti; Kushwaha, Archana; Kumar, Anil

2015-10-01

Cowpea (Vigna unguiculata), is an important arid legume with a good source of energy, protein, vitamins, minerals and dietary fibre. Sprouting of legumes enhances the bioavailability and digestibility of nutrients and therefore plays an important role in human nutrition. Improved varieties of grain cowpea viz. Pant Lobia-1 (PL-1) and Pant Lobia-2 (PL-2) and Pant Lobia-3 (PL-3) were examined for sprouting characteristics and associated changes in nutritional quality. Soaking time, sprouting time and sprouting temperature combinations for desirable sprout length of ¼ to ½ inch for cowpea seed samples were standardized. All the observations were taken in triplicate except soaking time, where six observations were taken in a completely randomized design of three treatments. Results revealed that optimum soaking time of PL-1 and PL-2 seed was 3 h whereas PL-3 required 9 h. Sprouting period of 24 h at 25 °C was found to be desirable for obtaining good sprouts. Significant improvement in nutritional quality was observed after sprouting at 25 °C for 24 h; protein increased by 9-12 %, vitamin C increased by 4-38 times, phytic acid decreased by 4-16 times, trypsin inhibitor activity decreased by 28-55 % along with an increase of 8-20 % in in-vitro protein digestibility.

Recent advances in cowpea [ Vigna unguiculata (L.) Walp.] “omics ...

African Journals Online (AJOL)

After decades of research on cowpea, significant amount of omics datasets are available and useful in understanding the genetic relationship between Vigna unguiculata ssp. unguiculata and other species belonging to the same genus as well as its genetic variation. Besides, the development of genetic map allowed the ...

Ambient temperature and genotype differentially affect developmental and phenotypic plasticity in Arabidopsis thaliana.

Science.gov (United States)

Ibañez, Carla; Poeschl, Yvonne; Peterson, Tom; Bellstädt, Julia; Denk, Kathrin; Gogol-Döring, Andreas; Quint, Marcel; Delker, Carolin

2017-07-06

Global increase in ambient temperatures constitute a significant challenge to wild and cultivated plant species. Forward genetic analyses of individual temperature-responsive traits have resulted in the identification of several signaling and response components. However, a comprehensive knowledge about temperature sensitivity of different developmental stages and the contribution of natural variation is still scarce and fragmented at best. Here, we systematically analyze thermomorphogenesis throughout a complete life cycle in ten natural Arabidopsis thaliana accessions grown under long day conditions in four different temperatures ranging from 16 to 28 °C. We used Q 10 , GxE, phenotypic divergence and correlation analyses to assess temperature sensitivity and genotype effects of more than 30 morphometric and developmental traits representing five phenotype classes. We found that genotype and temperature differentially affected plant growth and development with variing strengths. Furthermore, overall correlations among phenotypic temperature responses was relatively low which seems to be caused by differential capacities for temperature adaptations of individual accessions. Genotype-specific temperature responses may be attractive targets for future forward genetic approaches and accession-specific thermomorphogenesis maps may aid the assessment of functional relevance of known and novel regulatory components.

New observations on gametogenic development and reproductive experimental tools to support seed yield improvement in cowpea [Vigna unguiculata (L.) Walp].

Science.gov (United States)

Salinas-Gamboa, Rigel; Johnson, Susan D; Sánchez-León, Nidia; Koltunow, Anna M G; Vielle-Calzada, Jean-Philippe

2016-06-01

Cowpea reproductive tools. Vigna unguiculata L. Walp. (cowpea) is recognized as a major legume food crop in Africa, but seed yields remain low in most varieties adapted to local conditions. The development of hybrid cowpea seed that could be saved after each generation, enabling significant yield increases, will require manipulation of reproductive development from a sexual to an asexual mode. To develop new technologies that could support the biotechnological manipulation of reproductive development in cowpea, we examined gametogenesis and seed formation in two transformable, African-adapted, day-length-insensitive varieties. Here, we show that these two varieties exhibit distinct morphological and phenological traits but share a common developmental sequence in terms of ovule formation and gametogenesis. We present a reproductive calendar that allows prediction of male and female gametogenesis on the basis of sporophytic parameters related to floral bud size and reproductive organ development, determining that gametogenesis occurs more rapidly in the anther than in the ovule. We also show that the mode of megagametogenesis is of the Polygonum-type and not Oenothera-type, as previously reported. Finally, we developed a whole-mount immunolocalization protocol and applied it to detect meiotic proteins in the cowpea megaspore mother cell, opening opportunities for comparing the dynamics of protein localization during male and female meiosis, as well as other reproductive events in this emerging legume model system.

Improving growth and yield of cowpea by foliar application of ...

African Journals Online (AJOL)

Water stress impaired cowpea plant growth and decreased ion percentage and chlorophyll and carbohydrate concentration in the shoot as well as yield and its quality. Foliar-applied chitosan, in particular 250 mg/l, increased plant growth, yield and its quality as well as physiological constituents in plant shoot under stressed ...

Cowpea N rhizodeposition and its below-ground transfer to a co-existing and to a subsequent millet crop on a sandy soil of the Sudano-Sahelian eco-zone

DEFF Research Database (Denmark)

Laberge, Guillaume; Haussmann, Bettina I.G.; Ambus, Per

2011-01-01

Nitrogen (N) rhizodeposition by cowpea (Vigna unguiculata (L.) Walp) is potentially a large N source in cropping systems of Sub-Saharan Africa. A field experiment was conducted to measure cowpea N rhizodeposition under the conditions of the Sudano-Sahelian zone using direct 15N labelling techniques...... to trace the amount of deposition and its transfer to associated and subsequent crops. Half of the total cowpea crop N was located below-ground at plant maturity, which exceeded 20 kg N ha−1 when intercropped with millet. Only 15% of the below-ground cowpea N was recovered in roots, while 85% was found...... in the rhizodeposited pools. The experiment demonstrated that direct below-ground N transfer occurred from cowpea to millet in intercrop at a rate of 2 kg N ha−1 over the growing season. Forty percent of the 25 kg below-ground N that the cowpea crop left at harvest were identifiable in the top 0.30 m soil...

Natural infection of cowpea (Vigna unguiculata (L.) Walp.) by toxigenic fungi and mycotoxin contamination in Benin, West Africa

DEFF Research Database (Denmark)

Houssou, P.A.; Ahohuendo, B.C.; Fandohan, P.

2009-01-01

for the two periods. About 23 fungal species were identified on cowpea seed samples across zones of which Aspergillus flavus, a fungus that produces aflatoxins, was most frequently encountered. Fusarium species shown to produce fumonisins were not recorded from cowpea seeds. Overall incidence of A. flavus...... infection was found to increase after storage from 7.6% at T0 to 28.25% at T3. In spite of this natural infection of cowpea, very low levels of fumonisin and aflatoxin were detected. Only three out of the 92 cowpea samples, all collected at T0, were found to be fumonisin B1 positive with a mean level of 0.......03 mg/g. Similarly, only six samples out of the 92, all collected at T3, were aflatoxin B1 positive with mean levels of 3.58 µg/kg. Fumonisin (B2 and B3) and aflatoxin (B2, G1 and G2) were not detected in any of the samples. Contrary to the situation with maize and groundnut where high levels of toxin...

Draft genome sequence of Bradyrhizobium sp. strain BR 3262, an effective microsymbiont recommended for cowpea inoculation in Brazil.

Science.gov (United States)

Simões-Araújo, Jean Luiz; Leite, Jakson; Marie Rouws, Luc Felicianus; Passos, Samuel Ribeiro; Xavier, Gustavo Ribeiro; Rumjanek, Norma Gouvêa; Zilli, Jerri Édson

The strain BR 3262 was isolated from nodule of cowpea (Vigna unguiculata L. Walp) growing in soil of the Atlantic Forest area in Brazil and it is reported as an efficient nitrogen fixing bacterium associated to cowpea. Firstly, this strain was assigned as Bradyrhizobium elkanii, however, recently a more detailed genetic and molecular characterization has indicated it could be a Bradyrhizobium pachyrhizi species. We report here the draft genome sequence of B. pachyrhizi strain BR 3262, an elite bacterium used as inoculant for cowpea. The whole genome with 116 scaffolds, 8,965,178bp and 63.8% of C+G content for BR 3262 was obtained using Illumina MiSeq sequencing technology. Annotation was added by the RAST prokaryotic genome annotation service and shown 8369 coding sequences, 52 RNAs genes, classified in 504 subsystems. Published by Elsevier Editora Ltda.

Draft genome sequence of Bradyrhizobium sp. strain BR 3262, an effective microsymbiont recommended for cowpea inoculation in Brazil

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Jean Luiz Simões-Araújo

Full Text Available Abstract The strain BR 3262 was isolated from nodule of cowpea (Vigna unguiculata L. Walp growing in soil of the Atlantic Forest area in Brazil and it is reported as an efficient nitrogen fixing bacterium associated to cowpea. Firstly, this strain was assigned as Bradyrhizobium elkanii, however, recently a more detailed genetic and molecular characterization has indicated it could be a Bradyrhizobium pachyrhizi species. We report here the draft genome sequence of B. pachyrhizi strain BR 3262, an elite bacterium used as inoculant for cowpea. The whole genome with 116 scaffolds, 8,965,178 bp and 63.8% of C+G content for BR 3262 was obtained using Illumina MiSeq sequencing technology. Annotation was added by the RAST prokaryotic genome annotation service and shown 8369 coding sequences, 52 RNAs genes, classified in 504 subsystems.

Effect of thermal treatments on the chemical and biological value of irradiated and non-irradiated cowpea bean (Vigna unguiculata L. Walp) flour

International Nuclear Information System (INIS)

Dario, A.C.; Salgado, J.M.

1994-01-01

Chemical and nutritional characteristics of irradiated and nonirradiated cowpea bean at 0.2 kGy submitted to several thermal treatments were studied. The cowpea bean flours irradiated at 0.2 kGy were superior to those non-irradiated concerning digestibility and the flours submitted to microwave oven were superior to those cooked under low pressure, autoclaved or even raw from the nutritional point of view. As to the presence of anti-nutritional factors, the results showed that the variety of cowpea bean under research presented neither trypsin inhibitor nor haemagglutinin activity, however, regarding tannin, a 0.006% content was found and considered negligible

Comparisonof physicochemical properties of selected locally available legume varieties (mung bean, cowpea and soybean

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Kulasooriyage Tharuka Gunathilake

2016-10-01

Full Text Available Grain legumes are widely used as high-protein contained crops that play a secondary role to cereal or root crops. In Sri Lanka various legume species are cultivated and often utilised in the whole grain boiled form. The objective of present study was to analyse and compare locally grown legumes varieties; Mung bean (MI 5, MI 6, Cowpea (Bombay, Waruni, Dhawal, MICP1, ANKCP1 and soybean (pb1, MISB1 for their morphological characteristics, proximate and mineral composition (Fe, Ca, Zn, K, P. Seed shape, seed coat texture and colour, seed size and 100 seed weight (g were observed morphological characteristics in present study. Most of the characteristics of mung bean and soybean were similar within their species whereas characteristics of cowpea varieties largely differed. Values of 100 seed weight among the varieties of mung bean, soybean and cowpea were ranged from 5.8 - 6.5 g, 13.5 - 14.1 g and 13.4 - 17.2 g, respectively. The moisture content of all legume seeds ranged from 6.81% to 11.99%. Results were shown that the protein content significantly higher in soybean (36.56 - 39.70% followed by mung bean (26.56 - 25.99% and cowpea (25.22 - 22.84% respectively. Range of total carbohydrate, crude fat, crude fibre and total ash contents of nine legume varieties varied from 15.29 - 62.97%, 1.25 - 22.02%, 3.04 - 7.93% and 3.43 - 6.35 respectively. potassium (K, phosphorus (P, calcium (Ca, iron (Fe and zinc (Zn ranged from 1000 - 1900, 360 - 669, 15.0 - 192.3, 2.26 - 11.6 and 1.67 - 4.26 mg.100g-1 respectively in all the species of studied legume varieties. The wide variation in the chemical and physical properties of observed nine legume varieties, suggesting possible applications for various end-use products. 

Effect of Malting on the Chemical Composition of Cowpea ( Vigna ...

African Journals Online (AJOL)

The out-of-steep grains were germinated in the dark for 72 hours and oven dried at 50 °C. The malts were analyzed for diastatic activity and their contents of moisture, protein, sugar, fat, peroxidation products, phytate, tannin and trypsin inhibitor. Results: After malting, the diastatic activity of cowpea increased from 28.87 to ...

Productivity of Roselle/cowpea intercropping system in a semi-arid ...

African Journals Online (AJOL)

The effects of three planting densities (27,700; 37,000 and 55,500 plants ha-1) of roselle grown sole or intercropped with cowpea were investigated in two field trials in the 1997 and 1998 wet seasons at Sokoto. The leaf area index (LAI) of roselle was highest with the highest roselle planting density in the sole or ...

Yield performance of cowpea plant introductions grown in calcareous soils

Science.gov (United States)

Cowpea or Southernpea [Vigna unguiculata (L.) Walp.] is an important legume crop used as a feed for livestock, as a green vegetable and for consumption of its dry beans which provide 22-25% protein. The crop is very sensitive to alkaline soil conditions. When grown at a soil pH of 7.5 or higher, co...

Mutational analysis of the genome-linked protein of cowpea mosaic virus

NARCIS (Netherlands)

Carette, J.E.; Kujawa, A.; Gühl, K.; Verver, J.; Wellink, J.; Kammen, van A.

2001-01-01

In this study we have performed a mutational analysis of the cowpea mosaic comovirus (CPMV) genome-linked protein VPg to discern the structural requirements necessary for proper functioning of VPg. Either changing the serine residue linking VPg to RNA at a tyrosine or a threonine or changing the

Genetic diversity and a population structure analysis of accessions in the Chinese cowpea [Vigna unguiculata (L. Walp.] germplasm collection

Directory of Open Access Journals (Sweden)

Honglin Chen

2017-10-01

Full Text Available Cowpea (Vigna unguiculata is an important legume crop with diverse uses. The species is presently a minor crop, and evaluation of its genetic diversity has been very limited. In this study, a total of 200 genic and 100 genomic simple sequence repeat (SSR markers were developed from cowpea unigene and genome sequences, respectively. Among them, 27 genic and 27 genomic SSR markers were polymorphic and were used for assessment of genetic diversity and population structure in 105 selected cowpea accessions. A total of 155 alleles and 2.9 alleles per marker were identified, and the average polymorphic information content (PIC value was 0.3615. The average PIC of genomic SSRs (0.3996 was higher than that of genic SSRs (0.3235, and most of the polymorphic genomic SSRs were composed of di- and trinucleotide repeats (51.9% and 37.0% of all loci, respectively. The low level of detected genetic diversity may be attributed to a severe genetic bottleneck that occurred during the cowpea domestication process. The accessions were classified by structure and cluster analysis into four subgroups that correlated well with their geographic origins or collection sites. The classification results were also consistent with the results from principal coordinate analysis and can be used as a guide during future germplasm collection and selection of accessions as breeding materials for cultivar improvement. The newly developed genic and genomic SSR markers described in this study will be valuable genomic resources for the assessment of genetic diversity, population structure, evaluation of germplasm accessions, construction of genetic maps, identification of genes of interest, and application of marker-assisted selection in cowpea breeding programs.

Structure, morphogenesis and function of tubular structures induced by cowpea mosaic virus

NARCIS (Netherlands)

Kasteel, D.T.J.

1999-01-01

During systemic plant infection, viruses move from the initially infected cells through plasmodesmata to neighbouring cells. Different mechanisms have been proposed for this cell-to-cell movement. Cowpea mosaic virus (CPMV) employs one of the major movement mechanisms, i.e. tubule-guided

Effects of manufactured nano-copper on copper uptake, bioaccumulation and enzyme activities in cowpea grown on soil substrate.

Science.gov (United States)

Ogunkunle, Clement O; Jimoh, Mahboob A; Asogwa, Nnaemeka T; Viswanathan, K; Vishwakarma, Vinita; Fatoba, Paul O

2018-07-15

Increased use of nanoparticles-based products in agriculture portends important implications for agriculture. Therefore, the impact of nano-copper particles (nano-Cu for 65 days. Results indicated significant (Pnano-Cu levels compared to control, and bioaccumulation increased in seeds by at least 250%. Response of antioxidant enzymes to both nano-Cu types was concentration-dependent. Activity of APX and GR was enhanced in leaves and roots in response to both nano-Cu treatments in similar patterns compared to control. Both nano-Cu increased CAT activity in roots while SOD activity reduced in both leaves and roots. This shows that response of antioxidant enzymes to nano-Cu toxicity was organ-specific in cowpea. Malondialdehyde, a measure of lipid peroxidation, increased at 500 -1000 mg/kg of 25 nm nano-Cu in leaves by average of 8.4%, and 60-80 nm nano-Cu in root by 52.8%, showing particle-size and organ-dependent toxicity of nano-Cu. In conclusion, exposure of cowpea to nano-Cu treatments increased both the uptake and bioaccumulation of Cu, and also promoted the activity of APX and GR in root and leaf tissues of cowpea. Therefore, APX- and GR-activity level could be a useful predictive biomarker of nano-Cu toxicity in cowpea. Copyright © 2018 Elsevier Inc. All rights reserved.

Insects observed on cowpea flowers in three districts in the central ...

African Journals Online (AJOL)

The main insects observed on the cowpea flowers were bees such as Apis mellifera, Ceratina sp, Megachile sp, Xylocopa calens, Xylocopa imitator, Braussepis sp., .Lipotriches sp., Melecta sp and Amegilla sp. and other insects, such as thrips, flies, butterflies / moths, beetles, and Dysdercus sp. Thrips were the insects most ...

The major economic field diseases of cowpea in the humid agro ...

African Journals Online (AJOL)

Cowpea, which has now become an important protein source for the teeming populace of Nigerians especially those living in the humid agro-ecological zones of South-western Nigeria, is severely attacked by diseases. The causal agents of these diseases find the environment more conducive for survival and hence induce ...

Comparative Analysis of the Combined Effects of Different Water and Phosphate Levels on Growth and Biological Nitrogen Fixation of Nine Cowpea Varieties

OpenAIRE

Jemo, Martin; Sulieman, Saad; Bekkaoui, Faouzi; Olomide, Oluwatosin A. K.; Hashem, Abeer; Abd_Allah, Elsayed Fathi; Alqarawi, Abdulaziz A.; Tran, Lam-Son Phan

2017-01-01

Water deficit and phosphate (Pi) deficiency adversely affect growth and biological nitrogen fixation (BNF) of legume crops. In this study, we examined the impact of interaction between soil water conditions and available soil-Pi levels on growth, nodule development and BNF potential of nine cowpea varieties grown on dry savanna soils. In our experimental design, soils with different available soil-Pi levels, i.e., low, moderate, and high soil-Pi levels, collected from various farming fields w...

EFFECT OF CRUDE CASSAVA WATER EXTRACT AS A NATURAL HERBICIDE ON PROXIMATE COMPOSITION AND BIOACCUMULATION OF HYDROCYANIC ACID IN FOOD COMPONENTS OF COWPEA -VIGNA UNGUICULATA (L WALP

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Olajumoke Oke FAYINMINNU

2013-06-01

Full Text Available This study was a field trial of two experiments to examine the effect of crude cassava water extract (CCWE as a natural post-emergence herbicide on nutritional quality and bioaccumulation of hydrocyanic acid in cowpea seeds. The spraying of CCWE on cowpea plants was carried out weekly for 5weeks. Treatments of CCWE at 25 and 50% concentrations of MS6 (Manihot Selection, TMS30555 (Tropical Manihot Selection and Bulk CCWE (different cassava varieties, hand weeded and unweeded (controls were laid in randomised complete block design with three replications respectively. At maturity, dry samples of cowpea `Ife brown` seeds were ground to fine powder and the proximate composition and bioaccumulation of hydrocyanic acid in the two experiments were determined. Significant variations (p0.05 among the herbicide treatments. It was therefore recommended that CCWE could be used as a natural post-emergence herbicide in cowpea production without altering the nutritional quality and residue of hydrocyanic acid in cowpea seeds.

Distribution and Phylogeny of Microsymbionts Associated with Cowpea (Vigna unguiculata) Nodulation in Three Agroecological Regions of Mozambique.

Science.gov (United States)

Chidebe, Ifeoma N; Jaiswal, Sanjay K; Dakora, Felix D

2018-01-15

Cowpea derives most of its N nutrition from biological nitrogen fixation (BNF) via symbiotic bacteroids in root nodules. In Sub-Saharan Africa, the diversity and biogeographic distribution of bacterial microsymbionts nodulating cowpea and other indigenous legumes are not well understood, though needed for increased legume production. The aim of this study was to describe the distribution and phylogenies of rhizobia at different agroecological regions of Mozambique using PCR of the BOX element (BOX-PCR), restriction fragment length polymorphism of the internal transcribed spacer (ITS-RFLP), and sequence analysis of ribosomal, symbiotic, and housekeeping genes. A total of 122 microsymbionts isolated from two cowpea varieties (IT-1263 and IT-18) grouped into 17 clades within the BOX-PCR dendrogram. The PCR-ITS analysis yielded 17 ITS types for the bacterial isolates, while ITS-RFLP analysis placed all test isolates in six distinct clusters (I to VI). BLAST n sequence analysis of 16S rRNA and four housekeeping genes ( glnII , gyrB , recA , and rpoB ) showed their alignment with Rhizobium and Bradyrhizobium species. The results revealed a group of highly diverse and adapted cowpea-nodulating microsymbionts which included Bradyrhizobium pachyrhizi , Bradyrhizobium arachidis , Bradyrhizobium yuanmingense , and a novel Bradyrhizobium sp., as well as Rhizobium tropici , Rhizobium pusense , and Neorhizobium galegae in Mozambican soils. Discordances observed in single-gene phylogenies could be attributed to horizontal gene transfer and/or subsequent recombinations of the genes. Natural deletion of 60 bp of the gyrB region was observed in isolate TUTVU7; however, this deletion effect on DNA gyrase function still needs to be confirmed. The inconsistency of nifH with core gene phylogenies suggested differences in the evolutionary history of both chromosomal and symbiotic genes. IMPORTANCE A diverse group of both Bradyrhizobium and Rhizobium species responsible for cowpea

Genotyping three SNPs affecting warfarin drug response by isothermal real-time HDA assays.

Science.gov (United States)

Li, Ying; Jortani, Saeed A; Ramey-Hartung, Bronwyn; Hudson, Elizabeth; Lemieux, Bertrand; Kong, Huimin

2011-01-14

The response to the anticoagulant drug warfarin is greatly affected by genetic polymorphisms in the VKORC1 and CYP2C9 genes. Genotyping these polymorphisms has been shown to be important in reducing the time of the trial and error process for finding the maintenance dose of warfarin thus reducing the risk of adverse effects of the drug. We developed a real-time isothermal DNA amplification system for genotyping three single nucleotide polymorphisms (SNPs) that influence warfarin response. For each SNP, real-time isothermal Helicase Dependent Amplification (HDA) reactions were performed to amplify a DNA fragment containing the SNP. Amplicons were detected by fluorescently labeled allele specific probes during real-time HDA amplification. Fifty clinical samples were analyzed by the HDA-based method, generating a total of 150 results. Of these, 148 were consistent between the HDA-based assays and a reference method. The two samples with unresolved HDA-based test results were repeated and found to be consistent with the reference method. The HDA-based assays demonstrated a clinically acceptable performance for genotyping the VKORC1 -1639G>A SNP and two SNPs (430C>T and 1075A>C) for the CYP2C9 enzyme (CYP2C9*2 and CYP2C9*3), all of which are relevant in warfarin pharmacogenentics. Copyright © 2010 Elsevier B.V. All rights reserved.

Are investments in an informal seed system for cowpea a worthwhile endeavour?

NARCIS (Netherlands)

Biemond, P.C.; Stomph, T.J.; Kamara, A.; Abdoulaye, T.; Hearne, S.; Struik, P.C.

2012-01-01

High seed quality is a critical component for realising yield potential. For smallholder cowpea farmers in northern Nigeria the informal seed system is a major supplier of genetically high-quality seed, but the physiological quality of farmers’ produced seed remains unknown. The project “Promoting

In vitro digestibility of processed and fermented soya bean, cowpea and maize

NARCIS (Netherlands)

Kiers, J.L.; Nout, M.J.R.; Rombouts, F.M.

2000-01-01

Tropical legumes, ie soya bean and cowpea, were pre-treated and subsequently fermented using pure cultures of Rhizopus spp. Impact of soaking, cooking and fermentation of the legumes on their digestibility was determined using an in vitro digestion method. Processing of white maize included, amongst

Growth and yield of cassava as influenced by maize and cowpea ...

African Journals Online (AJOL)

Two field trials were conducted at the research farm of the National Root Crops Research Institute (NRCRI) Umudike, Igbariam sub-station (060151N, 060521E) in 2013/2014 and 2014/2015 cropping seasons to determine the growth and yield of cassava as influenced by maize and cowpea population densities. Cassava at ...

Integration of Gamma Irradiation and Some Botanical oils To Protect Cowpea And Chickpea Seeds From Infestation With The Bruchid Beetle Callosobruchus Maculatus

International Nuclear Information System (INIS)

Hassan, R.S.; Mikhaiel, A.A.; Sileem, Th.M.

2013-01-01

The lethal effect of gamma radiation doses of 0.75 or 1.0 kGy on the adults Callosobruchus maculates reared on cowpeas and chickpeas were slow during the first and third days post-treatments. By increasing the dose to 1.5 kGy, the values of the percent mortality of adults in both seeds 24 h posttreatment were 53 and 40%, respectively. On the other hand, the dose 2 kGy caused sooner mortality for adults post-treatment for cowpeas. Different concentrations from eight plant oils; lemon grass, pinus sylvestris, parsley, fennel, geranium, peppermint, petitgrain and sweet basil, were used for protection of cowpea and chickpea seeds from infestation by Callosobruchus maculates. The results showed that sweet basil and geranium caused 89 and 79 % larval mortality, respectively, in case of cowpeas at concentration 0.5 % with exposure period of 48 hour while 71.0 and 63.33% adult mortality was occurred at the same concentration of both oils in chickpeas. The latent effects of tested plant oils on adult stage when beetles of C. maculatus were fed on seeds treated with the lowest two concentrations (0.0312, 0.0625%) of tested oils, the number of eggs laid per female was decreased in female exposed to all tested oils especially in case of cowpea treated with sweet basil and lemongrass. Most of the tested oils caused high reduction in larval penetration in both types of seeds. The adult weight was non significantly reduced at all treatments. The use of different plant oils leads to reduction in the progeny comparing to the control and sweet basil or geranium was found to be highly effective in decreasing the percentage of emergence (30 and 40% , respectively). No harmful effect was observed on germination of plant oils treated cowpea and chickpea seeds with concentration 2%.

DEVELOPMENT OF PIGEON PEA INOCULATED WITH RHIZOBIUM ISOLATED FROM COWPEA TRAP HOST PLANTS

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SALOMÃO LIMA GUIMARÃES

2016-01-01

Full Text Available Pigeon pea is an important protein source grown in several tropical and sub - tropical countries, and is considered a multi - purpose plant that is resistant to the conditions of the Brazilian Cerrado. Among the possible uses for cowpea, its use as a green manure, increasing soil nitrogen content through the association with diazotrophic bacteria, generically known as rhizobia, is noteworthy. The present work aimed to evaluate the efficiency of Rhizobium strains isolated from cowpea plants in the development of pigeon peas cultured in Red Latosol. The experiment was conducted in a greenhouse, using a completely randomized design with seven treatments and four replications. Treatments consisted of inoculation with four Rhizobium strains (MT8, MT15, MT16, and MT23 and one commercial inoculant comprising Bradyrhizobium spp. strains BR 2801 and BR 2003. There were two controls, one absolute (without inoculation or nitrogen fertilization and the other with nitrogen fertilization. Each experimental plot consisted of an 8 - dm 3 vase containing three plants. Analyzed variables included plant height, SPAD index, number and dry weight of nodules, and shoot and root dry masses. Pigeon peas responded significantly to inoculation treatment, since all the plants inoculated with Rhizobium strains isolated from cowpea strains showed results similar to plants in the nitrogen control and commercial inoculant treatments. This demonstrates a favorable plant – bacteria interaction, which can be utilized as an alternative nitrogen source for pigeon peas.

Monitoring soil coverage and yield of cowpea furrow irrigated with saline water

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Antonia Leila Rocha Neves

Full Text Available Abstract Cowpea crop is of great importance for northeast Brazil. The objective of this work was to evaluate the application of saline water in different developing stages on plant growth and changes in soil characteristics, measured by soil coverage, and on yield of cowpea plants. The experiment was conducted under field conditions, during the dry season in a completely randomized block design with five treatments and five replications. Each experimental unit consisted of 4 lines of plants with 5.0 m long. The treatments evaluated were: 1. irrigation with groundwater with electrical conductivity (ECw of 0.8 dS m-1 during the whole crop cycle; 2. saline water (5.0 dS m-1 during the whole crop cycle; 3, 4 and 5. saline water (5.0 dS m-1 up to 22nd, during 23rd to 42nd and from the 43rd to 62nd days after sowing, respectively, and groundwater in the remaining period. Soil coverage was evaluated by digital images using the software ENVI for image processing and classification. It was found that the continuous use of saline water inhibits plant growth, while irrigation with saline water during germination and initial growth stages caused retardation in plant development, but in this last case a recovery was observed in the final part of the experimental period. For treatments 2 and 3, a reduction was verified in the number of pods and in seed production, as compared to other treatments. Irrigation with saline water during 23 to 42 and 43 to 62 days after sowing did not affect reproductive and vegetative growth, but the saline water application in the pre-flowering (treatment 4 caused anticipation of the reproductive cycle.

Death by desiccation: Effects of hermetic storage on cowpea bruchids

KAUST Repository

Murdock, Larry L.

2012-04-01

When cowpea grain is stored in airtight containers, destructive populations of the cowpea bruchid (. Callosobruchus maculatus) don\\'t develop even though the grain put into the store is already infested with sufficient . C. maculatus to destroy the entire store within a few months. The surprising effectiveness of hermetic storage for preserving grain against insect pests has long been linked with the depletion of oxygen in the hermetic container and with the parallel rise in carbon dioxide. With . C. maculatus, low oxygen (hypoxia) leads to cessation of larval feeding activity, whereas elevated levels of carbon dioxide (hypercarbia) have little or no effect on feeding. Cessation of feeding arrests the growth of the insects, which don\\'t mature and don\\'t reproduce. As a result, population growth ceases and damaging infestations don\\'t develop. . C. maculatus eggs, larvae, and pupae subjected to hypoxia eventually die after exposures of various duration. The cause of death is desiccation resulting from an inadequate supply of water. We demonstrate that blocking the supply of oxygen interdicts the main supply of water for . C. maculatus. This leads to inactivity, cessation of population growth, desiccation and eventual death. © 2012 Elsevier Ltd.

Phylogenetic multilocus sequence analysis of indigenous slow-growing rhizobia nodulating cowpea (Vigna unguiculata L.) in Greece.

Science.gov (United States)

Tampakaki, Anastasia P; Fotiadis, Christos T; Ntatsi, Georgia; Savvas, Dimitrios

2017-04-01

Cowpea (Vigna unguiculata) is a promiscuous grain legume, capable of establishing efficient symbiosis with diverse symbiotic bacteria, mainly slow-growing rhizobial species belonging to the genus Bradyrhizobium. Although much research has been done on cowpea-nodulating bacteria in various countries around the world, little is known about the genetic and symbiotic diversity of indigenous cowpea rhizobia in European soils. In the present study, the genetic and symbiotic diversity of indigenous rhizobia isolated from field-grown cowpea nodules in three geographically different Greek regions were studied. Forty-five authenticated strains were subjected to a polyphasic approach. ERIC-PCR based fingerprinting analysis grouped the isolates into seven groups and representative strains of each group were further analyzed. The analysis of the rrs gene showed that the strains belong to different species of the genus Bradyrhizobium. The analysis of the 16S-23S IGS region showed that the strains from each geographic region were characterized by distinct IGS types which may represent novel phylogenetic lineages, closely related to the type species of Bradyrhizobium pachyrhizi, Bradyrhizobium ferriligni and Bradyrhizobium liaoningense. MLSA analysis of three housekeeping genes (recA, glnII, and gyrB) showed the close relatedness of our strains with B. pachyrhizi PAC48 T and B. liaoningense USDA 3622 T and confirmed that the B. liaoningense-related isolate VUEP21 may constitute a novel species within Bradyrhizobium. Moreover, symbiotic gene phylogenies, based on nodC and nifH genes, showed that the B. pachyrhizi-related isolates belonged to symbiovar vignae, whereas the B. liaoningense-related isolates may represent a novel symbiovar. Copyright © 2017 Elsevier GmbH. All rights reserved.

Cowpeas and pinto beans: yields and light efficiency of candidate space crops in the Laboratory Biosphere closed ecological system

Science.gov (United States)

Nelson, M.; Dempster, W. F.; Silverstone, S.; Alling, A.; Allen, J. P.; van Thillo, M.

An experiment utilizing cowpeas Vigna unguiculata pinto beans Phaseolus vulgaris L and Apogee ultra-dwarf wheat was conducted in the soil-based closed ecological facility Laboratory Biosphere from February to May 2005 The lighting regime was 13 hours light 11 hours dark at a light intensity of 960 mu mol m -2 s -1 45 moles m -2 day -1 supplied by high-pressure sodium lamps The pinto beans and cowpeas were grown at two different plant densities The pinto bean produced 710 g m -2 total aboveground biomass and 341 g m -2 at 33 5 plants per m 2 and at 37 5 plants per m 2 produced 1092 g m -2 total biomass and 537 g m -2 of dry seed an increase of almost 50 Cowpeas at 28 plants m -2 yielded 1060 g m -2 of total biomass and 387 g seed m -2 outproducing the less dense planting by more than double 209 in biomass and 86 more seed as the planting of 21 plants m -2 produced 508 g m-2 of total biomass and 209 g m-2 of seed Edible yield rate EYR for the denser cowpea bean was 4 6 g m -2 day -1 vs 2 5 g m -2 day -1 for the less dense stand average yield was 3 5 g m -2 day -1 EYR for the denser pinto bean was 8 5 g m -2 day -1 vs 5 3 g m -2 day -1 average EYR for the pinto beans was 7 0 g m -2 day -1 Yield efficiency rate YER the ratio of edible to non-edible biomass was 0 97 for the dense pinto bean 0 92 for the less dense pinto bean and average 0 94 for the entire crop The cowpeas

Effect of oil palm sludge on cowpea nodulation and weed control in ...

African Journals Online (AJOL)

STORAGESEVER

2008-08-18

Aug 18, 2008 ... weed control in the humid forest zone of Nigeria ... tropics, where rainfall is scanty and soils are sandy with ... Impact of oil palm sludge on 3 cultivars of cowpea length or roots at 6 and 8 WAP in wet and dry season. 6 WAP.

Proteolytic processing of the primary translation products of cowpea mosaic virus RNAs

NARCIS (Netherlands)

Franssen, H.

1984-01-01

Cowpea mosaic virus (CPMV) is the type member of a group of plant viruses, the comoviruses, with a genome consisting of two single stranded RNA molecules separately encapsidated in icosahedral particles. A characteristic feature of the two genome RNAs is that they are both polyadenylated at their

Genes and sequences involved in the replication of cowpea mosaic virus RNAs

NARCIS (Netherlands)

Eggen, R.

1989-01-01

The aim of the studies described in this thesis was to gain more insight in the complex molecular mechanisms underlying the RNA replication of the cowpea mosaic virus genome. Previously the replication of CPMV RNA has been examined extensively with crude membrane fractions prepared from