Effect of Harvesting Stage and Drying Method on Cowpea Leaf Nutrient Composition

Cowpea leaves are lost annually due to infestation and spoilage when being transported to clients and the losses at the local markets are brought on by inadequate postharvest handling procedures and market glut, particularly during peak seasons. High moisture content from the cowpea leaves at harvest stage may contribute to increased spoilage hence lowering quantity and quality. The choice of appropriate harvesting stage and drying method can help to reduce this problem. The aim of this study was to determine the best harvesting stage and efficient drying method that would maintain high leaf nutrient composition. Cowpeas variety M66 was used for the research and the treatments included three harvesting stages (21, 35 and 49 days after sowing [DAS]), three drying methods (open sun, solar dryer and oven. Data was collected on iron, calcium, crude fibre, beta carotene, protein and moisture content. The data was subjected for variance using Statistical Analysis System 9.2 edition and significantly different means separated using least significant difference at 5%. The results indicated significant (p<0.05) differences in moisture, calcium, proteins, beta carotene and crude fibre content in both trials. Harvest stage and drying method did not significantly (p<0.05) influence the iron content. Oven and solar drying methods showed better nutrient and mineral retention in the three harvesting stages when compared to the open sun drying method.

Effect of Different Cooking Methods on the Concentration of Vitamin C in Cowpea Vegetable (Vigna unguiculata)

Background: Vitamin C is a water-soluble vitamin widely distributed in nature, mostly rich in fresh fruits and green leafy vegetables. The amount of Vitamin C in a given food depends on soil condition, climate in their area of growth, storage condition after harvest, and methods of preparation. Much amount of Vitamin C in vegetables is lost during cooking and there are still limited information on the impact of different cooking methods on the vitamin C content in leafy vegetable like cowpea vegetable (Vigna unguiculata). It is upon this background that this study aimed to determine the concentration of Vitamin C in cowpea vegetable when cooked using different cooking methods. Methodology: Vitamin C concentration in a solution of cowpea vegetable cooked by different cooking methods (boiling, steaming and microwave methods) was determined by a redox titration using iodine in the presence of starch indicator. This was conducted at Busitema University, Faculty of Science and Education, Biology Laboratory in Uganda. Results: The study revealed that cooking cowpea vegetable using microwave yields the highest concentration of vitamin C (154.8 mg/L), followed by steaming (142.9 mg/L) and boiling yielding the least concentration of vitamin C (130.4 mg/L). Conclusion: The concentration of vitamin C obtained by the three methods of cooking cowpea vegetable has shown that microwaving method of cooking yields the highest concentration of vitamin C followed by steaming method and finally boiling. Further studies should be done to explain the variation of vitamin C concentration in cowpea vegetable when cooked using the above cooking methods. Similar studies should be conducted on other leafy vegetables which are potential sources of Vitamin C.

Technological potential of under-utilized starches from eight varieties of legumes grown in Cameroon / Potencial tecnológico de amidos subutilizados de oito variedades de leguminosas cultivadas nos Camarões

Abstract Starch samples from eight legumes cultivars instar of one variety of Vigna unguiculata L. (Cowpea), one variety of Vigna subterrenea V. (Bambara groundnut) and six varieties of Phaseolus vulgaris L. (Common bean), grown in Cameroon were isolated, and their physicochemical and pasting properties were evaluated. The objectives of the study were to investigate the starch properties and processing characteristics of different bean varieties, and to establish the basic foundation of improving the functionality of beans and their starch grown in the region. The result revealed significant differences amongst the properties of the starches. The swelling power of the legume starch isolates put them in the category of highly restricted-swelling starch. This characteristic is desirable for the manufacture of value-added products such as noodles and composite blends with cereals. The pasting properties were determined using a rapid visco analyzer, and various legumes bean starches exhibited different pasting profiles. The high breakdown viscosity (BV) was founded for Cowpea and Bambara groundnut and confirmed their low. ability to resist heat and shear stress when compared to Common bean varieties studies. The factors which influence the pasting characteristics resulting to decrease in peak viscosity (PV), trough viscosity (TV) and final viscosity (FV) of starch are attributed to the interaction of starch with the protein, fat, etc. which depended to their variety.

Resumo Foram isoladas amostras de amido de oito cultivares de leguminosas ínstar de uma variedade de Vigna unguiculata L. (feijão caupi), uma variedade de Vigna subterrenea V. (amendoim Bambara) e seis variedades de Phaseolus vulgaris L. (feijão comum), cultivadas nos Camarões, e suas propriedades físico-químicas e de pasta foram avaliadas. Os objetivos do estudo foram investigar as propriedades do amido e as características de processamento de diferentes variedades de feijão e estabelecer as bases básicas para melhorar a funcionalidade do feijão e do amido cultivado na região. O resultado revelou diferenças significativas entre as propriedades dos amidos. O poder de inchamento dos isolados de amido de leguminosas os coloca na categoria de amido com inchamento altamente restrito. Esta característica é desejável para o fabrico de produtos de valor acrescentado, tais como macarrão e misturas compósitas com cereais. As propriedades de pasta foram determinadas usando um analisador rápido de visco, e vários amidos de feijão leguminosos exibiram diferentes perfis de pasta. A alta BV foi fundada para o amendoim Cowpea e Bambara e confirmou sua baixa. capacidade de resistir ao calor e tensão de cisalhamento quando comparado com estudos de variedades de feijão. Os fatores que influenciam as características colantes resultantes da diminuição do pico de viscosidade (PV), da viscosidade mínima (TV) e da viscosidade final (FV) do amido são atribuídos à interação do amido com a proteína, gordura, etc., que dependem da sua variedade.

Exploring spatial dependence of cowpea-beans yield using global and local autocorrelation statistics in the Eastern Cariri region of Paraíba / Explorando a dependência espacial da produtividade do feijão-caupi usando estatísticas globais e locais de autocorrelação na região do Cariri oriental da Paraíba

ABSTRACT: This study evaluated the variability and characterizedthe spatial dependence between some soil attributes in the Eastern Cariri microregion of Paraíba,and analyzed the spatial correlations in order to identify the interactions between such attributes in cowpea bean(Vigna unguiculata L. Walp)production. Harvest data of the agricultural years of 2000-2017 in the Eastern Cariri microregion of Paraíba were analyzed. Parameters of the fitted models wereestimated using the Maximum Likelihood method and the performance of the models was evaluated based on coefficients of determination(R2), maximum log-likelihood function, and Schwarz's Bayesian information criterion (BIC). Correlation and spatial autocorrelation between the cowpea productivity and agrometeorological elements was detected through the spatial analysis, using techniques such as the Moran's index I. The study showed that, according to the performance indicators used, the spatial error model offered better results in relation to the classical multiple regression models and the self-regressive spatial models, indicating that the inclusion of spatial dependence in the models improves the estimate of productivity of cowpea in the microregion of Cariri Oriental da Paraíba.

RESUMO: O estudo tem por finalidade avaliar a variabilidade e caracterizar a dependência espacial entre alguns atributos dos solos na microrregião do Cariri Oriental da Paraíba, bem como estudar as correlações espaciais para identificar as interações entre tais atributos na produção do feijão-caupi. O estudo foi realizado com os dados das safras dos anos agrícolas de 2000-2017, da microrregião do Cariri Oriental da Paraíba. A estimativa de parâmetros dos modelos ajustados foi obtida utilizando o método de Máxima Verossimilhança e a avaliação do desempenho dos modelos foi realizada com base no coeficiente de determinação (R2), no máximo valor do logaritmo da função verossimilhança e no critério de informação bayesiano de Schwarz (BIC). Este estudo também permitiu verificar a correlação e autocorrelação espacial entre a produtividade do feijão e dos elementos agrometeorológicos, por meio da análise espacial, usando de técnicas como o índice I de Moran. O estudo mostrou que, de acordo com os indicadores de desempenho utilizados, o modelo de erro espacial ofereceu melhores resultados em relação aos modelos clássicos de regressão múltipla e aos modelos espaciais autorregressivos, indicando que a inclusão da dependência espacial nos modelos melhora a estimativa da produtividade do feijão-caupi em a microrregião do Cariri Oriental da Paraíba.

Genetic dissection of yield associated traits in a cross between cowpea and yard-long bean (Vigna unguiculata (L.) Walp.) based on DArT markers

Both cowpea and yard-long bean belong to Vigna unguiculata ssp. unguiculata but have diverged through human induced evolution in sub-Saharan Africa and Asia, respectively. To map the quantitative trait loci (QTLs) for yield associated traits and derive new lines that may combine the attributes of both types, we developed a F2:3 mapping population derived from a cross between cowpea line TVu2185 and yard-long bean line TVu6642. Using DArT markers, a total of 30 QTLs accounting for 1.8–13.0% phenotypic variation was detected for pod and seed traits. Some novel major QTLs for peduncle number per plant (qPeN2.2), pod length (qPoL3), seed breadth (qSB4), length (qSL7.2) and thickness (qST9) identified on chromosomes 2, 3, 4, 7 and 9, respectively, are particularly interesting and need to be validated. Moreover, we confirmed previously reported QTLs for pod length (qPoL8) and 100-seed weight (qSW8) on chromosome 8 and for seed number per pod (qSN9.2) on chromosome 9 suggesting usefulness for marker-assisted-selection purpose. Notably, some QTLs for these traits were clustered especially on chromosomes 5, 7, 8, 9 and 10 indicating the presence of the same QTL or linked loci in these regions. Moreover, the involvement of epistasis was observed for trait expressions, but compared with the main effect QTLs, the phenotypic effects of epistatic-QTLs detected were much less. The present QTL analysis may provide a useful tool for breeders to formulate efficient breeding strategy for introgression of the desirable alleles for yield related traits in cowpea using molecular markers.

Toxicity of the essential oil of basil cultivars and hybrids and its repellent effect on stored grain pests / Toxicidade do óleo essencial de cultivares e híbridos de manjericão e seu efeito repelente sobre pragas de grãos armazenados

Essential oils have emerged as an alternative to synthetic insecticides in the control of stored grain pests. The toxicity and repellency of the essential oils of four basil cultivars and three basil hybrids and the monoterpenes linalool, citral, and (E)-methyl cinnamate were evaluated in the stored grain pests Callosobruchus maculatus and Sitophillus zeamais. The essential oils of the cultivar Genovese and the hybrid 'Genovese' x 'Maria Bonita' were more toxic to C. maculatus. Conversely, the essential oils of the cultivar Sweet Dani and the hybrid 'Cinnamom' x 'Maria Bonita' were more toxic to S. zeamais. Among the monoterpenes, (E)-methyl cinnamate was the most toxic to both pests, taking 0.14 and 0.34 µ L.mL-1 to kill 50% of the C. maculatus and S. zeamais populations, respectively. All essential oils from cultivars, hybrids, and monoterpenes were repellent to S. zeamais, except for (E)-methyl cinnamate. For C. maculatus, this effect was lower, being citral the most repellent compound. Results demonstrate the insecticidal potential of the essential oil of O. basilicum and its monoterpenes in the control of stored grain pests.

Os óleos essenciais surgem como alternativa aos inseticidas sintéticos no controle das pragas de grãos armazenados. A toxicidade e a repelência dos óleos essenciais de quatro cultivares e três híbridos de manjericão e dos monoterpenos linalol, citral e (E)-cinamato de metila foram avaliadas nas pragas de grãos armazenados Callosobruchus maculatus e Sitophillus zeamais. Os óleos essenciais da cultivar Genovese e do híbrido 'Genovese' x 'Maria Bonita' foram mais tóxicos para C. maculatus. Já para S. zeamais, os óleos essenciais das cultivar Sweet Dani e do híbrido 'Cinnamom' x 'Maria Bonita' apresentaram maior toxicidade. Dentre os monoterpenos, o (E)-cinamato de metila foi o mais tóxico para ambas as pragas. Foram necessários 0,14 e 0,34 µ L.mL-1 para matar 50% da população de C. maculatus e S. zeamais. Todos os óleos essenciais das cultivares, dos híbridos e dos monoterpenos foram repelentes a S. zeamais, com exceção do (E)-cinamato de metila. Já para C. maculatus, este efeito foi reduzido, sendo o citral o composto mais repelente. Nos resultados demonstram o potencial inseticida dos óleos essenciais de O. basilicum e seus monoterpenos para o controle de pragas de grãos armazenados.

Population parameters as a way to evaluate the risk of attack of Aphis craccivora (Hemiptera: Aphididae) on cowpea / Parâmetros populacionais como forma de avaliar os riscos de ataque de Aphis craccivora (Hemiptera: Aphididae) em feijão-caupi

The objective of this research was to develop fertility life tables in order to estimate the population parameters of black aphid (Aphis craccivora Koch) in cowpea (Vigna unguiculata) varieties, aiming to propose a risk scale for its use. The experiment consisted of six treatments and six replicates (five varieties plus the cultivar VITA 7 as a susceptible control). A cohort was formed with six adult females distributed in six replicates of each genotype, and the insects were observed daily. Based on the data, fertility life tables were drawn for each variety and the population parameters were estimated. The different values of the finite growth rate (λ) were considered to propose a risk scale for the use of the genotypes. The results obtained give the dimension of the variability of V. unguiculata in respect to the character, resistance to A. craccivora, with antibiosis as the main mechanism of resistance. Considering all the results, the varieties studied can be classified according to their suitability as a plant favorable to the development of the black aphid as follows: VITA 7 > CE-13 > CE-51 > CE-08 = CE-07. The proposal of a risk scale for the use of V. unguiculata genotypes against the A. craccivora population, based on the finite growth rate (λ) values, was adequate to discriminate the varieties studied.(AU)

Objetivou-se nesta pesquisa elaborar tabelas de vida de fertilidade com o intuito de estimar os parâmetros populacionais de pulgão-preto (Aphis craccivora Koch) em variedades de feijão-caupi (Vigna unguiculata), visando propor uma escala de risco para o seu uso. O experimento constituiu-se em seis tratamentos (cinco variedades mais o cultivar VITA 7 como padrão de suscetibilidade) com seis repetições. Formou-se uma coorte com seis fêmeas adultas distribuídas em cada genótipo, sendo todos os indivíduos observados diariamente. De posse dos dados, foram elaboradas tabelas de vida de fertilidade para cada variedade e estimados os parâmetros populacionais. Para propor uma escala de risco de uso de genótipos, ponderou-se sob os diferentes valores da razão finita de crescimento (λ). Os resultados obtidos dão a dimensão da variabilidade de V. unguiculata com relação ao caráter da resistência a A. craccivora, sendo a antibiose o principal mecanismo de resistência associado. Considerando-se todos os resultados, foi possível hierarquizar as variedades estudadas segundo sua aptidão como planta favorável ao desenvolvimento ao pulgão-preto conforme segue: VITA 7 >> CE-13 > CE-51 > CE-08 = CE-07. A proposta de uma escala de risco do uso de genótipos de V. unguiculata frente à população de A. craccivora, baseada nos valores da razão finita de crescimento (λ), foi adequada para discriminar as variedades estudadas.(AU)

Influence of weather parameters on Aphis craccivora and Bean common mosaic virus disease incidence in Vigna unguiculata L. Walp

Aim: Many crop modelling and climate simulation studies have reported variability in pest and pathogen distribution as well as their interaction with host. These prediction encourages to revisit the pest and pathogen epidemological and distribution studies in light of changing climate. In line with above assumption, the present field study was carried out to study the population dynamics of cowpea aphid (Aphis craccivora) and its influence on BCMV disease incidence. Methodology: In this field experiment, A. craccivora population and BCMV disease incidence data were collected in different standard meteorological weeks of 2013-2014 and 2014-2015. Impact of weather parameters on A. craccivora and BCMV disease incidence was statistically analyzed. Results: The significant change in A. craccivora population and BCMV disease incidence was documented during the study. The maximum aphid population was observed during rabi season and less was observed in kharif and summer season. Whereas, incidence of BCMV was recorded maximum in rabi season. Correlation analysis affirmed, minimum temperature (Tmin) and rainfall had negative impact on A. craccivora whereas weather parameters had non-significant impact on BCMV disease incidence. The regression models developed from the present study explained 41.4 % to 78.8 % and 18.5 % to 46.1% variability (R2) of aphid population and BCMV incidence, respectively. Interpretation: The weather parameters had more impact on A. craccivora population than BCMV disease incidence and merely presence of maximum number of A. craccivora was not a deciding factor for outbreak of virus disease incidence.

Leveraging barrel medic genome sequence for the development and use of genomic resources for genetic analysis and breeding in legumes

BACKGROUND: A total of 62,591 cowpea expressed sequence tags (ESTs) were BLAST aligned to the whole-genome sequence of barrel medic (Medicago truncatula) to develop conserved intron scanning primers (CISPs). The efficacy of the primers was tested across 10 different legumes and on different varieties of cowpea, chickpea, and pigeon pea. Genetic diversity was assessed using the same primers on different cowpea genotypes. Singlenucleotide polymorphisms (SNPs) were detected, which were later converted to length polymorphism markers for easy genotyping. CISPs developed in this study were used in tagging resistance to bacterial leaf blight disease in cowpea. RESULTS: A total of 1262 CISPs were designed. The single-copy amplification success rates using these primers on 10 different legumes and on different varieties of cowpea, chickpea, and pigeon pea were approximately 60% in most of the legumes except soybean (47%) and peanut (37%). Genetic diversity analysis of 35 cowpea genotypes using 179 CISPs revealed 123 polymorphic markers with PIC values ranging from 0.05 to 0.59. Potential SNPs identified in cowpea, chickpea, and pigeon pea were converted to PCR primers of various sizes for easy genotyping. Using the markers developed in this study, a genetic linkage map was constructed with 11 linkage groups in cowpea. QTL mapping with 194 F3 progeny families derived from the cross C-152 × V-16 resulted in the identification of three QTLs for resistance to bacterial leaf blight disease. Conclusions: CISPs were proved to be efficient markers to identify various other marker classes like SNPs through comparative genomic studies in lesser studied crops and to aid in systematic sampling of the entire genome for well-distributed markers at low cost

Laccase production by Myrothecium gramineum and its optimization under solid state fermentation using cowpea pod as substrate

The present study highlights the utilization of wastes such as cowpea outer pod generated from agro industries forlaccase production using Myrothecium gramineum LCJ177 under solid-state fermentation. Conventional methodswere used to optimize the process parameters. The classical one-factor-at-a-time method showed that the optimalstarch concentration was 1 g/L, peptone concentration was 0.5 g/L, copper sulfate concentration was 0.6 mM, andpyrogallol concentration was 0.8 mM. Likewise, the suitable physical conditions were an initial pH of five of theculture medium, the temperature of 30°C and moisture content of 60%. Utilization of dried cowpea outer pod as asubstrate reduces the pollution levels by converting agro-wastes as useful by-products.

Biochemical Composition of Seed and Husk of Cowpea (Vigna unguiculata (L.) Walp.) Infected by Colletotrichum destructivum O’Gara in Storage

Colletotrichum destructivum was isolated from infected seeds and pods of cowpea (Var. IAR-48) with typical symptoms of anthracnose disease. The fungus during the pathogenesis, reduced the protein, fat, ash, crude fibre, carbohydrate, calcium and phosphorus, and increased the amount of iron, sodium, zinc, magnesium and potassium in the infected seed and husk. The carbohydrate, protein and phosphorus contents in the healthy husk reduced from 55.05%, 11.21% and 171.85 mg to 39.94%, 8.92% and 42.92 respectively in the infected sample whereas potassium and sodium contents in the healthy pod increased from 1.03 mg and 78.29 to 2.90 mg and 100.65 mg respectively in the infected husk. The potassium, sodium, magnesium and iron increased from 1292.25 mg, 0.19 mg, 0.09 mg and 11.00 mg in the healthy seeds to 1536.03 mg, 0.28 mg, 0.21 mg and 13.19 mg respectively in the infected seeds. The fungus caused the depletion of phosphorus from 498. 06 mg in the healthy to 430.17 mg in the infected seed, protein from 24.09% to 17.86%, carbohydrate from 57.02% to 34.35%, fat from 1.70% to 1.33% and crude fibre from 3.94% to 2.61%. The average loss of the major nutrient values; protein, carbohydrate and fat were 28.95% and 22.55% for seed and husk respectively after 8 weeks of planting.

Reaction of yellow passion fruit to passion fruit woodiness disease and to bacterial spot / Reação de maracujazeiro azedo à virose do endurecimento dos frutos e à bacteriose

The use of resistant varieties is a promising strategy for passion fruit woodiness disease (PWD) (Cowpea aphid-borne mosaic virus - CABMV) and bacterial spot (Xanthomonas axonopodis pv. passiflorae - Xap) control in yellow passion fruit (Passiflora edulis Sims). This study aimed at evaluating the reaction of nine genotypes of yellow passion fruit to both mechanically inoculated CABMV and Xap, under protected cultivation. The experiment was conducted using a randomized block design with subdivided parcels comprised of nine treatments, four repetitions, six replications per genotype, and five evaluations. Disease incidence (% plants infected) and severity (% of total leaf area with necrotic lesions or leaf symptoms) were calculated at 7-day intervals. All genotypes evaluated were classified as moderately susceptible to PWD. MAR20#10, MAR20#41, and Rosa Intenso were classified as moderately resistant to bacterial spot whereas the remaining genotypes were classified as moderately susceptible. Genotypes Rosa Intenso, MAR20#41, MAR20#15, and MSCA stood out for presenting the lowest PWD mean severity scores as well as the greatest numbers of plants presenting resistance to PWD after five evaluations. MAR20#10, MAR20#41, and Rosa Intenso demonstrated the lowest bacterial spot mean severity scores. Among the genotypes selected, Rosa Intenso and MAR20#41 were the most promising genotypes for presenting the lowest severity scores for both PWD and bacterial spot disease.

O uso de variedades resistentes é uma estratégia promissora para o controle da virose do endurecimento dos frutos (VEF) (Cowpea aphid-borne mosaic virus - CABMV) e da bacteriose (Xanthomonas axonopodis pv. passiflorae - Xap) no maracujazeiro amarelo (Passiflora edulis Sims). Este estudo objetivou avaliar a reação de nove genótipos de maracujazeiro amarelo à CABMV e Xap, ambos inoculados mecanicamente, sob cultivo protegido. O experimento foi conduzido em delineamento de blocos casualizados com parcelas subdivididas, composto por nove tratamentos, quatro repetições, seis plantas por genótipo e cinco avaliações. A incidência (% plantas infectadas) e a severidade (% da área foliar total com lesões necróticas ou sintomas foliares) das doenças foram calculadas em intervalos de sete dias. Todos os genótipos avaliados foram classificados como moderadamente suscetíveis à VEF. MAR20#10, MAR20#41 e Rosa Intenso foram classificados como moderadamente resistente à bacteriose enquanto os demais genótipos foram classificados como moderadamente suscetíveis. Os genótipos Rosa Intenso, MAR20#41, MAR20#15 e MSCA se destacaram por apresentarem menores severidades médias da VEF bem como pelo maior número de plantas apresentando resistência à virose após as cinco avaliações. MAR20#10, MAR20#41 e Rosa Intenso demonstraram as menores severidades médias de bacteriose. Entre os genótipos selecionados, Rosa Intenso e MAR20#41 foram os mais promissores por apresentarem os menores valores de severidade para a VEF e para a bacteriose.

The behavior of Aphis gossypii and Aphis craccivora (Hemiptera: Aphididae) and of their predator Cycloneda sanguinea (Coleoptera: Coccinellidae) in cotton-cowpea intercropping systems

ABSTRACT The intercropping is an important cultural practice commonly used in pest management. It is based on the principle that increased plant diversity in the agro-ecosystem can lead to reductions of pest populations in the crop. The current study aimed to assess the impact the colored fiber cotton-cowpea intercropped systems on Aphis gossypii and Aphis craccivora and on their predator Cycloneda sanguinea and the losses and the dispersion behavior of these aphids and their predator in these cropping systems. The experiment had a randomized block experimental design with two bioassays and four treatments. The number of apterous and alate aphids (A. gossypii) per cotton plant was 1.46 and 1.73 or 1.97 and 2.19 times highest in the solid cotton system than that found in the cotton-cowpea intercropped systems (S1) and (S2), respectively. On the other hand, the cotton-cowpea intercropped systems (S1 and S2) reduced, respectively, in 43% and 31% the number of apterousA. gossypiiper cotton plant compared to the control. Implementing cotton-cowpea intercropped system in the S1 scheme reduced A. gossypii infestation, favored the multiplication of C. sanguinea, and allowed obtaining heavier open bolls.

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

ABSTRACT 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.

Protection effect of the anthraquinones, cassiatorin and aurantio-obtusin from seeds of Senna tora against cowpea weevil attack

Objective:To explore the potential insecticidal,ovipositor deterrent and antifeedant effects of ethyl acetate extract of the seeds of Senna tora (Syn.Cassia tora) against cowpea weevil (Callosobruchus maculaws).Methods:The activities were evaluated using standard protocols.In these bioassays,the cowpea seeds were used directly as an insect feed.The activity of the extract and isolated compounds were tested at concentrations of 100,200 and 300 μg/mL and compared to neem oil and cinnamaldehyde (as standard positive controls).Phytochemical analysis of the ethyl acetate extract was done through a number of chromatographic techniques and the structures of the isolated compounds were established through comprehensive spectroscopic analysis including 2D-NMR and ESI-MS studies.Results:Fractionation of the active ethyl acetate extract resulted in the isolation of one known anthraquinone,aurantio-obtusin (1) and a novel compound that was named as cassiatorin (2).Compounds 1 and 2 showed comparable insect antifeedant properties with the positive controls while their insecticidal and ovipositor deterrent effects were far superior to the standard controls.Contusions:It is thus concluded that Senna tora extracts and the isolated compounds (1 and 2) may be employed in the postharvest management of stored cowpea seeds and as other crop protectants.

Protection effect of the anthraquinones, cassiatorin and aurantio-obtusin from seeds of Senna tora against cowpea weevil attack

Objective: To explore the potential insecticidal, ovipositor deterrent and antifeedant effects of ethyl acetate extract of the seeds of Senna tora (Syn. Cassia tora) against cowpea weevil (Callosobruchus maculatus). Methods: The activities were evaluated using standard protocols. In these bioassays, the cowpea seeds were used directly as an insect feed. The activity of the extract and isolated compounds were tested at concentrations of 100, 200 and 300 μg/mL and compared to neem oil and cinnamaldehyde (as standard positive controls). Phytochemical analysis of the ethyl acetate extract was done through a number of chromatographic techniques and the structures of the isolated compounds were established through comprehensive spectroscopic analysis including 2D-NMR and ESI-MS studies. Results: Fractionation of the active ethyl acetate extract resulted in the isolation of one known anthraquinone, aurantio-obtusin (1) and a novel compound that was named as cassiatorin (2). Compounds 1 and 2 showed comparable insect antifeedant properties with the positive controls while their insecticidal and ovipositor deterrent effects were far superior to the standard controls. Conclusions: It is thus concluded that Senna tora extracts and the isolated compounds (1 and 2) may be employed in the postharvest management of stored cowpea seeds and as other crop protectants.

Draft genome sequence of Bradyrhizobium manausense strain BR 3351T, an effective symbiont isolated from Amazon rainforest

ABSTRACT The strain BR 3351T (Bradyrhizobium manausense) was obtained from nodules of cowpea (Vigna unguiculata L. Walp) growing in soil collected from Amazon rainforest. Furthermore, it was observed that the strain has high capacity to fix nitrogen symbiotically in symbioses with cowpea. We report here the draft genome sequence of strain BR 3351T. The information presented will be important for comparative analysis of nodulation and nitrogen fixation for diazotrophic bacteria. A draft genome with 9,145,311 bp and 62.9% of GC content was assembled in 127 scaffolds using 100 bp pair-end Illumina MiSeq system. The RAST annotation identified 8603 coding sequences, 51 RNAs genes, classified in 504 subsystems.

Technological potential of under-utilized starches from eight varieties of legumes grown in Cameroon

Abstract Starch samples from eight legumes cultivars instar of one variety of Vigna unguiculata L. (Cowpea), one variety of Vigna subterrenea V. (Bambara groundnut) and six varieties of Phaseolus vulgaris L. (Common bean), grown in Cameroon were isolated, and their physicochemical and pasting properties were evaluated. The objectives of the study were to investigate the starch properties and processing characteristics of different bean varieties, and to establish the basic foundation of improving the functionality of beans and their starch grown in the region. The result revealed significant differences amongst the properties of the starches. The swelling power of the legume starch isolates put them in the category of highly restricted-swelling starch. This characteristic is desirable for the manufacture of value-added products such as noodles and composite blends with cereals. The pasting properties were determined using a rapid visco analyzer, and various legumes bean starches exhibited different pasting profiles. The high breakdown viscosity (BV) was founded for Cowpea and Bambara groundnut and confirmed their low. ability to resist heat and shear stress when compared to Common bean varieties studies. The factors which influence the pasting characteristics resulting to decrease in peak viscosity (PV), trough viscosity (TV) and final viscosity (FV) of starch are attributed to the interaction of starch with the protein, fat, etc. which depended to their variety.

Resumo Foram isoladas amostras de amido de oito cultivares de leguminosas ínstar de uma variedade de Vigna unguiculata L. (feijão caupi), uma variedade de Vigna subterrenea V. (amendoim Bambara) e seis variedades de Phaseolus vulgaris L. (feijão comum), cultivadas nos Camarões, e suas propriedades físico-químicas e de pasta foram avaliadas. Os objetivos do estudo foram investigar as propriedades do amido e as características de processamento de diferentes variedades de feijão e estabelecer as bases básicas para melhorar a funcionalidade do feijão e do amido cultivado na região. O resultado revelou diferenças significativas entre as propriedades dos amidos. O poder de inchamento dos isolados de amido de leguminosas os coloca na categoria de amido com inchamento altamente restrito. Esta característica é desejável para o fabrico de produtos de valor acrescentado, tais como macarrão e misturas compósitas com cereais. As propriedades de pasta foram determinadas usando um analisador rápido de visco, e vários amidos de feijão leguminosos exibiram diferentes perfis de pasta. A alta BV foi fundada para o amendoim Cowpea e Bambara e confirmou sua baixa. capacidade de resistir ao calor e tensão de cisalhamento quando comparado com estudos de variedades de feijão. Os fatores que influenciam as características colantes resultantes da diminuição do pico de viscosidade (PV), da viscosidade mínima (TV) e da viscosidade final (FV) do amido são atribuídos à interação do amido com a proteína, gordura, etc., que dependem da sua variedade.

Aplicação exógena do ácido salicílico em maracujazeiro-amarelo para o controle do vírus do endurecimento dos frutos / Exogenous application of salicylic acid in yellow passion fruit for the control of fruit woodiness virus

Foram avaliados o efeito do ácido salicílico (AS) no controle do Cowpea aphid-borne mosaic virus (CABMV), vírus que induz o endurecimento dos frutos do maracujazeiro (EFM), e a sua influência na expressão dos sintomas e na ativação das enzimas peroxidase e polifenoloxidase. O experimento foi delineado e conduzido de forma inteiramente casualizada. Os tratamentos consistiram em AS (2,5 mM) e controle (etanol 10%), aplicados 12 horas antes da inoculação mecânica do CABMV, agente causal do EFM no Brasil. Um experimento similar foi conduzido sob as mesmas condições, porém, quatro aplicações do AS foram realizadas semanalmente após a inoculação mecânica do CABMV. Em ambos os experimentos a avaliação da severidade da doença foi realizada empregando escala de notas que variaram de 0 a 3. Para avaliar a atividade das enzimas peroxidase e polifenoloxidase, as plantas foram tratadas (AS e controle) e, após 12 horas, inoculadas com o isolado de CABMV. Foram realizadas amostragens foliares 0, 12, 24 e 48 horas após os tratamentos (HAT), que foram processadas e analisadas em espectrofotômetro para a constatação da ativação da peroxidase e polifenoloxidase. Aos 30 dias após a inoculação (DAI), o AS aplicado uma única vez promoveu redução da severidade de 57,1%, quando comparado com o controle. Nas plantas submetidas às aplicações semanais de AS foi constatada a redução significativa da expressão dos sintomas aos 45 DAI. Nos ensaios bioquímicos foi observado aumento significativo de peroxidase nos intervalos de 12 horas (DAI)/24 horas (HAT). Para polifenoloxidase foi observado um aumento significativo de sua atividade nos intervalos de 24 horas (DAI)/48 horas (HAT). Sugere-se que o AS pode representar uma ferramenta adicional no manejo do EFM.(AU)

The effect of salicylic acid (SA) was evaluated in control of Cowpea aphid-borne mosaic virus (CABMV), which induces hardening of the fruits of passion fruit (EFM). Also, its influence on the expression of symptoms and the activation of peroxidase and polyphenol oxidases were evaluated. The experiment was designed and conducted in a completely random way. The treatments consisted of SA (2.5 mM) and control (10% ethanol), applied 12 hours before mechanical inoculation of CABMV, the causal agent of EFM in Brazil. A similar experiment was conducted under the same conditions, but four applications were performed weekly after CABMV mechanical inoculation. In both experiments a rating scale ranging from 0 to 3 was used to assess the severity of the disease. To evaluate the activity of peroxidase and polyphenol oxidase, the plants were treated (SA and control) and, after 12 hours, inoculated with isolated CABMV. Leaf samplings were performed at 0, 12, 24 and 48 hours after the treatments (HAT), processed and analyzed in a spectrophotometer to verify the activation of peroxidase and polyphenol oxidase. At 30 days after inoculation (DAI), the SA applied once promoted reduction of 57.1% of the severity, when compared with the control. In plants subjected to SA weekly applications, it was found a significantly reduction in the expression of symptoms at 45 DAI. In the biochemical assays, a significant increase in peroxidase in 12-hour intervals (DAI)/24 hours (HAT) was observed. For polyphenol oxidase, a significant increase of its activity was observed at 24 hour intervals (DAI)/48 hours (HAT). It is suggested that SA may represent an additional tool in the management of EFM.(AU)

Trichoderma asperellum isolated from salinity soil using rice straw waste as biocontrol agent for cowpea plant pathogens.

This study discusses isolation and identification new fungal isolate from salinity soil for controlling soil borne diseases. Among sixteen fungal, a potent isolate coded SRBP_ZSHSG1 was isolated from Sugar beet rhizospher samples collected from Al-Hosainia localities-El-Sharkia-Egypt. Traditional methods consistent with phylogenetic analysis of 18S rRNA sequences showed SRBP_ZSHSG1 has 100% similarity with Trichoderma strains and the most closest is Trichoderma asperellum. Thus, it proposed name Trichoderma asperellum SRBP_ZSHSG1 (ID: KP336489). Results proved SRBP_ZSHSG1 followed by T. roseum and Chaetomium globosum were highly inhibitors to the tested pathogens. These results were confirmed by field experiments. SRBP_ZSHSG1 was able to grow on rice straw (biostraw) and produce most active compounds. The biostaw extract was the most effective bioagent and recorded highest reduction in pathogen numbers. GC/MS analysis of ethyl acetate extract revealed the presence of 9 compounds. These compounds were determined 4 volatile alcohols (1-4) and fatty acid esters (5-9).