the study investigates consumers’ preference for cowpea reflected in the nigerian markets through price discounts and premiums that consumers pay for different cowpea characteristics. the price data used for this study were obtained through a market survey. a common data collection protocol was employed. every month, between october 2009 to december 2010, five cowpea samples per seller were bou...

There is uncertainty on how generally applicable near-infrared reflectance spectroscopy (NIRS) calibrations are across genotypes and environments, and this study tests how well a single calibration performs across a wide range of conditions. We also address the optimization of NIRS to perform the analysis of crude protein (CP) content in a variety of cowpea accessions (n = 561) representing gen...

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 cow...

The management of major field insect pests of cowpea under calendar and monitored sprays of cypermethrin was studied. The major insect pests studied were the cowpea aphid, Aphis craccivora Koch, legume bud thrips Megalurothrips sjostedti Tryb, legume pod borer, Maruca vitrata Fab. and pod sucking bugs. Influence of insect pest management on yield was also determined. The calendar sprays consist...

The performance of cowpea aphid, Aphis craccivora Koch. (Hemiptera: Aphididae), on five faba bean, Vicia faba L. (Fabales: Fabaceae) cultivars was evaluated. Colony development, biology, and demographic parameters were studied to measure the cowpea aphid performance. Two methods, whole plant and detached leaf, were used in these experiments. After 14 d , the number of apterous adult, nymphs, an...

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 colou...

Genetic diversity and phylogenetic relationships among 22 local cowpea (Vigna unguiculata) varieties and inbred lines collected throughout Senegal were evaluated using simple sequence repeat molecular markers. A set of 49 primer combinations were developed from cowpea genomic/expressed sequence tags and evaluated for their ability to detect polymorphisms among the various cowpea genotypes....

Martin, Daniel Thomas M.S., Purdue University, May 2014. Wheat Stored in Triple Layer Plastic Bags: Protection Against the Rice Weevil, Sitophilus oryzae L. (Coleoptera: Curcilionidae) and the Effect of Air Leaks on Hermetic Storage. Major Professor: Dr. Larry L. Murdock. The Purdue Improved Crop Storage system is a triple layer high-density polyethylene storage technology that has proven to be...

Cowpea (Vigna unguiculata) nodules contain three leghemoglobins (LbI, LbII, and LbIII) that are encoded by at least two genes. We have cloned and sequenced the gene that encodes for LbII (lbII), the most abundant Lb in cowpea nodules, using total DNA as the template for PCR. Primers were designed using the sequence of the soybean lbc gene. The lbII gene is 679 bp in length and codes for a predi...

An improved genetic linkage map has been constructed for cowpea (Vigna unguiculata L. Walp.) based on the segregation of various molecular markers and biological resistance traits in a population of 94 recombinant inbred lines (RILs) derived from the cross between 'IT84S-2049' and '524B'. A set of 242 molecular markers, mostly amplified fragment length polymorphism (AFLP), linked to 17 biologic...