Cowpea Varieties Research Articles

Cowpea cropping systems, traits preference and production constraints in the upper west region of Ghana: farmers' consultation and implications for breeding

BackgroundCowpea (Vigna unguiculata (L.) Walp) is used primarily as food for humans and feed for animals. It is also used for soil management within a cropping system. However, cowpea production is confronted with numerous challenges. As such farmers and consumers alike have certain preferences in terms of production and utilization. This present study investigated cowpea cropping systems, traits preference and production constraints among farmers in the Nandom, Lambusie and Lawra districts in the northern part of the Upper West Region of Ghana. A total of 306 farming households were sampled from the 3 chosen districts. Questionnaires and interviews were used for data collection. The IBM SPSS software, version 22, was employed to analyze the data using descriptive statistics, specifically frequencies, percentages and crosstabulations.ResultsThe study’s results indicated that a majority (58.5%) of the cowpea farmers practice intercropping, whereas a minority (41.5%) practice sole cropping. The farmers intercropped cowpea with maize, millet, sorghum and yam. Farmers preferred cowpea varieties with the following traits: high yield, drought tolerance, early maturing, pest resistance, improve soil fertility, high price, high demand, better taste, less cooking time, storage quality, palatability and fast growing. Farmers indicated that susceptibility to storage pests, high pest incidence, late maturity, difficulty in harvesting, high input cost, small grain size, low yield, high disease incidence, poor colour, lack of improved variety, and drought are some constraints that hinder cowpea production.ConclusionResults indicate a need for behavioural change communication to assist cowpea farmers to adopt improved and appropriate cropping systems. Farmers should be involved in cowpea technology development in order to understand their preferences and constraints to enable subsequent adoption of such technologies. The results from this study call for an interdisciplinary committee to plan and breed cowpea varieties that meet the needs of the farmers.

MORPHOPHYSIOLOGICAL CHARACTERS AND PRODUCTION OF COWPEA DUE TO VARIATION IN THE NUMBER OF SEEDS AND FERTILIZATION COMBINATION

Cowpea, known as a food crop, demonstrates thrive on land with low soil fertility. Albina IPB is a new superior variety of cowpea with a potential yield of 3.88-4.69 t ha-1. This study aims to evaluate the productivity of Albina based on differences in the number of seeds and fertilization. Minus one test method was applied to find out which nutrients among N, P, and K had the most influence on the growth and production of cowpea. The results showed that one seed per planting hole gave the best results which were significantly different from others, while the combination of three seeds per planting hole with minus K resulted in the lowest growth in general. Nevertheless, anthocyanin in the combination of three seeds per planting hole with minus K produced the highest value, significantly different from the other treatments. These results indicate that element K is a limiting element in the growth of cowpea. However, neither the fertilization treatment nor the number of seeds was significantly different in the yield and yield components. Plant productivity ranged from 0.82-1.42 t ha-1 for all treatments.

Evaluation of aflatoxin levels in selected varieties of cowpea in the Greater Accra Region, Ghana

Cowpea, a major source of food in Ghana is known for its nutritional benefits and is highly recommended for consumption to tackle malnutrition. Its production and distribution however are faced with challenges such as fungal and mycotoxin contamination. The aim of this study was to assess aflatoxin levels of common cowpea varieties in the Nima and Agbogbloshie markets and to explore if these levels fall within the acceptable consumption ranges. The aflatoxin levels of all the procured samples were analyzed following the Reveal Q+ protocol. All the samples analyzed contained aflatoxin at levels ranging from 2.1 to 12.6 ppb. Red beans cowpea variety from Nima market had the highest mean aflatoxin concentration (9.1 ppb) while Agbogbloshie Red beans variety had the lowest mean aflatoxin concentration (3.6 ppb). There was no significant difference between the aflatoxin level of both markets (p = 0.610) nor was there a significant difference between the aflatoxin levels in the cowpea varieties (p = 0.950). The results revealed in this study compromise food safety and could lead to serious health implications for consumers. Authorities in charge of food ensuring safety must provide important education and training to food crop vendors which will gradually lead to the total elimination of fungi and aflatoxin in food crops. Also, there should be periodic checks on the condition of cowpea and cowpea products in markets to boost food safety.

Effect of Cowpea Trap Crop on the Control of [Aphis gossypii (Glover)] in Zimbabwean Cotton

Cotton aphids are major cotton pests causing significant yield losses of more than 65% in Zimbabwe. Field experiments to investigate the effectiveness of cowpea as a trap crop in reducing aphid pressure on cotton were conducted over three seasons 2010/11 to 2013/14 at Cotton Research Institute (CRI) in Kadoma, and Umguza in Matebeleland North, in Zimbabwe. Incidence of aphid predators on sole cotton, cotton intercropped with cowpea trap crop and the trap crop itself were also assessed. The measurements were aphid scores, aphid predator counts in both sole cotton, intercropped cotton and cowpea trap crop. Seed cotton yield was measured. Aphid scores and predator counts were subjected to Analysis of Variance (ANOVA) using GenStat 14th Edition software. The square root transformation [x + 3/8] was used for scores or counts not normally distributed. At CRI Cowpea trap crop significantly controlled aphids in intercropped cotton better than chemical control using Acetamiprid 20 SP (P< 0.05). Coccinellid grubs (ladybird beetle larval) populations were highest in cowpea trap crop. At Umguza poor germination of cowpea resulted in highest Coccinellid adults (ladybird beetle adults) in intercropped cotton. Yield of intercropped cotton was comparable to yield from plots where Acetamiprid 20SP was used as a standard practice. Farmers can adopt this technology of aphid control in cotton using commercial cowpea variety CBC 3 as cotton aphid trap crop.

Comparative Spatial Distribution of Sucking Insect-Pest-Complex in Summer and Monsoon Cowpea [Vigna unguiculata (L.) Walp.

Background: Pulse crops are known as an important dietary source of proteins for a major part of the vegetarian population across the globe; especially in India. Legume crops help restoration of soil fertility through symbiotic nitrogen fixation. Spatial distribution is an important aspect as it interprets the interaction between individuals of the species and their habitat. The biological reason of aggregation is highly unpredictable and it depends on behavioural pattern of the insect; therefore, spatial distribution accounts for informative description of organisms. Methods: In order to study the spatial distribution of sucking pests of cowpea, a field trial was laid out during Zaid and Kharif separately at the Instructional Farm of Rajasthan College of Agriculture, Udaipur in 2019 and 2020. Cowpea variety Pusa Komal was cultivated in 6 plots each of 3 m x 3 m with the row to row and plant to plant spacing of 50 cm and 10 cm, respectively. Different distribution pattern were used to determine spatial distribution pattern of species of insect fauna associated with cowpea during the summer and monsoon season. Result: The spatial distribution for most the insect pest complex was contagious during both the respective seasons. All positive IDM (index of clumping) values confirmed the clumping of the pest during the season. The mean crowding index was more than unity, indicated clumped interaction.

Biochemical and histopathological assessment of transgenic cowpea in male Wistar rats

Cowpea is one of the most consumed legumes in Africa. Recombinant DNA technology has been used to insert foreign genes into plants genome thereby creating a new generation of plants with desired traits. Such plants possess improved seed quality, yield and resistance to pests and pathogens. The aim of this work is to assess the safety profile of an improved variety of cowpea by examining its effect on the liver and kidney.Native cowpea and improved variety of cowpea, IT89KD, were fed to Wistar rats which were divided into 3 groups. One group was fed poultry feed with 50% native cowpea and the second group was fed poultry feed with 50% improved cowpea variety while the control group was fed standard rat chow. At the end of 40 days feeding period, improved varieties group were found to have higher protein content than normal variety. Also, there was elevation in the following liver enzymes, Alanine Transaminase (ALT), Aspartate transaminase (AST) and bilirubin in the group fed with improved variety. The presence of black arrowheads and inflammation in liver and kidneys of rats fed with Genetically Modified(GM)cowpea was observed. This suggests that caution should be applied in the use of GM Cowpea as feed for Wistar rats and food for man.

Adaptive Capabilities of Two Varieties of Cowpea in Crude Oil-Contaminated and Un-Contaminated Soils

Adaptive Capabilities of Two Varieties of Cowpea in Crude Oil-Contaminated and Un-Contaminated Soils

Efficacy of the parasitic wasp, Dinarmus basalis Rondani (Hymenoptera: Pteromalidae), in reducing infestations by the cowpea beetle, Callosobruchus maculatus (L.) (Coleoptera: Chrysomelidae: Bruchinae)

BackgroundCowpea seed beetle, Callosobruchus maculatus (L.) (Coleoptera: Chrysomelidae: Bruchinae), is the most important pest of stored cowpea in tropical regions. This study was designed to determine the presence of parasitoids associated with C. maculatus, investigate the efficacy of the parasitic wasp, Dinarmus basalis Rondani (Hymenoptera: Pteromalidae), in controlling C. maculatus as influenced by time and number of applications and ascertain the use of olfactory cues by D. basalis in host searching. Three markets in Ibadan, Southwest Nigeria, namely: Bodija, Mapo and Ojoo, were purposively surveyed for parasitoids associated with C. maculatus. Two pairs of D. basalis were released at 3-day intervals into cowpea seeds previously infested with C. maculatus. Treatments included: four times of parasitoid applications (4-TPA), three applications (3-TPA), two applications (2-TPA), 1 application (1-TPA) and a control without parasitoid application (0-TPA). All treatments were replicated four times in a completely randomized design to determine F1 progeny of C. maculatus and seed damage. Olfactory bioassay was carried out with D. basalis adults placed in a Y-tube olfactometer; and their preference for infested or uninfested three cowpea varieties, namely: Ife Brown, Ife BPC (Branching Peduncle) and Oloyin, as well as infested cowpea grains or pure air was evaluated.ResultsAmong the previously known parasitoids associated with C. maculatus, only D. basalis was found in the sampled markets. F1 progeny of adult C. maculatus reduced from 4.75 individuals (0-TPA) to 1.25 (2-TPA), 0.25 (3-TPA) and 0 (4-TPA). Concurrently, the number of exit holes on cowpea seeds significantly (p < 0.05) ranged from 5.25 (0-TPA) > 3.21 (1-TPA) > 2.20 (2-TPA) > 2.18 (4-RAP) > 1.39 (3-TPA). Adults D. basalis were more attracted to infested grains of Ife Brown (χ2 = 4, df = 1, p = 0.0455) and infested grains of Ife BPC (χ2 = 4, df = 1, p = 0.0455) than clean air. Similarly, adults D. basalis were more attracted to infested Ife Brown than the uninfested (χ2 = 5, df = 1, p = 0.0254). The results further showed that there were non-significant differences between the infested and uninfested grains of Ife BPC (χ2 = 0.2, df = 1, p = 0.6547) and Oloyin (χ2 = 3.2, df = 1, p = 0.0736) varieties.ConclusionsAdult D. basalis reduced emergence of C maculatus and reduced damage in cowpea seeds. Olfactory cues played a necessary role in host-searching efforts of D. basalis.

Effect of Zinc Levels on Growth and Yield of Cowpea (Vigna unguiculata L.) Varieties

The field experiment was conducted at Crop Research Farm (CRF), Department of Agronomy, Sam Higginbottom University of Agriculture, Technology and Sciences, Prayagraj (U.P.) during Zaid season of 2022 on Cowpea crop. The treatments Consists of 3 levels of Zinc [20kg/ha, 0.6% and (10kg/ha + 0.3%)] and 3 different varieties (GOMTI, HIMANI-06, KASHI-KANCHAN) and a Control. The experiment was laid out in Randomized Block Design with 10 treatments replicated thrice. The application of Zinc (10kg/ha + 0.3%) + GOMTI variety recorded higher plant height (83.96 cm), more number of nodules per plant (9.20), maximum plant dry weight (12.55 g/plant), Crop growth rate (7.94 g/m2/day), Relative growth rate (0.037 g/g/day) and yield attributes namely Number of Pods per plant (14.44), Number of seeds per pod(18.55), Test weight(91.00 g), Seed yield (1.03 t/ha), Stover yield (5.33 t/ha) and Harvest index (16.12%) was found maximum in treatment 3 that is Zinc (10kg/ha + 0.3%) + GOMTI variety as compared to other treatment combinations. The maximum gross return (INR 112750.00/ha), net return (INR 74582.50/ha) and B:C ratio (1.95) is recorded in treatment 3 Zinc (10kg/ha + 0.3%) + GOMTI variety as well.

Effect of Spacing on Growth and Grain Yield of Cowpea Varieties (Vigna Unguiculata) in Guinea Savanna Zone, Nigeria

Purpose: Field experiment was conducted at the Biotechnology Advanced Research Centre Farm, Garki-Abuja during 2022 cropping season to evaluate the effect of spacing on growth and grain yield of cowpea varieties. The experimental plot was ploughed and harrowed after which lining out was carried out. There were 24 plots with three replications. Each replicate consisted of 8 plots. Each treatment was in a plot size of 2.0 m x 2.0 m (4.0 m2). The alley way between replicates plots was 1.0 m and within replicates was 1.0 m. The treatments consisted of four spacing, (65 x 20 cm, 75 x 20 cm, 85 x 20 cm and 95 x 20 cm) designated as S1, S2, S3, and S4 and two cowpea varieties (TVU 14346 and TVU 14788). The treatments were 4 x 2 factorial experiment and fitted into a Randomized Complete Block Design (RCBD), replicated three times and data were collected on plant height per plant, number of leaves per plant, number of pods, pod length, number of seeds per plant, 100 seed weight, seed weight and grain seed yield. The seeds were sourced from the International Institute of Tropical Agriculture IITA) Ibadan. Two seeds were planted at the depth of 4 cm and later thinned to one three weeks after planting.&#x0D; Methodology: The treatments were subjected to analysis of variance (ANOVA) using CROP STAT statistical package and significant means compared using Duncan Multiple Range Test (DMRT).&#x0D; Findings: Results obtained revealed that the growth parameters of the plants increased as the plant aged with the highest number of leaves obtained from TVU 14788 (40.20) variety. There was significant (p≤0.05) difference in the yield performance with the highest grain yield gotten from TVU 14788 (7.42 t/ha) and the plants spaced with S1 (8.79 t/ha) gave the highest mean grain yield while the least mean value was received from S4 (3.98 t/ha).&#x0D; Unique Contribution to Theory, Practice and Policy: From this study, it could be stated that for optimum yield performance TVU 14788 and S1 thrived better than other treatments evaluated and could be recommended for farmers within this ecological zone.

Comparative Evaluation of Neem Seed Extract as Bio-insecticide for the Control of Three Field Insect Pests of Cowpea in Maiduguri, Borno State, Arid Zone of Nigeria

Cowpea Vigna unguiculata is an important source of nutritious food for man for healthy living and provides fodder to the animal for optimum production and grows in the ecological part of Nigeria. However, despite its importance to man and national development, its main cultivation challenge is insect pests which sometimes account for as high as 40 % loss in production. The continuous use of conventional insecticides to control pests is resulting in unbearable health hazards, hence the need for alternative control measures such as the use of botanicals. This study evaluated the efficacy of neem seed extract biopesticide compared to cypermethrin synthetic insecticide for the management of Thrips, Maruca vitrata and Clavigralla tomentosicollis on cowpea varieties in Maiduguri, Borno State of Nigeria. The neem seed extract was extracted following standard procedures and used as a treatment alongside cypermethrin against the three pests at weekly intervals on four cowpea varieties. Pest population buildup was monitored for five weeks on treated and untreated (control) crops beginning from 24 hours after each treatment on weekly bases. The result revealed a significant reduction (P&gt;0.05) in the population buildup of the three pests on both neem seed oil and cypermethrin-treated crops compared to the control. No significant difference (P&gt;0.05) in population reduction was observed between crops treated with neem seed extract and Cypermethrin. Consequently, there was a significant increase in the grain yield of cowpea on treated plots compared to untreated plots. The neem seed extract has demonstrated a high potential substitute for synthetic insecticide to control the three insect pests.

Influence of Phosphorus and Zinc Application on Leaf Area Ratio (LAR) of Cowpea (Vigna unguiculata (L.) Walp) Varieties in the Scrub Savanna of Nigeria

Currently there is increasing attention to evaluate the possible Relative Growth Rate (RGR) of plant species, and to evaluate whether the disparities are principally caused by structural or by physiological characters. Leaf area ratio (LAR) of plant is defined as leaf area per unit total plant biomass and net assimilation rate. Phosphorus (P) and Zinc (Zn) are the most important factors affecting LAR of cowpea (Vigna unguiculata L. Walp). Two field trials were conducted at the Faculty of Agriculture and Agricultural Engineering Research Farm of Abubakar Tafawa Balewa University, Bauchi, North Eastern, Nigeria, between 2006 and 2007. The experiments consisted of fifty-four (54) treatments consisting of six varieties by three SSP levels by three Zinc levels. The objective of this study was to examine whether there are disparities in the LAR of cowpea varieties at different P and Zn levels or none? Bauchi is located at 100 22’, N latitude and 900 47’ E longitude at about 109.45m above sea level. Results indicated that year, varieties, P and Zn were found to have significant (P&lt;0.05) effect on LAR. Kanannado recorded the highest LAR than other five varieties. The differences in LAR observed in the varieties may be attributed to the differences in phenotypes and climatic factors such as rainfall, sunshine and availability of nutrients. The increase in LAR indicated an encouraging influence on crop growth rate, dry matter and yield. Application of SSP at 50kgha-1 to Kanannado and IT89KD-288 was observed to be more valuable for enhancement of LAR and hence recommended for growers in the study area.

Cowpea Yield Under Water Stress Scenarios

Cowpea is considered a subsistence crop, so it is generally cultivated by family farming in the rainy season and, outside this season, with the aid of irrigation. Its yield is reduced if there is water stress due to the lack of rainfall or irrigation water. Objective of this study was to evaluate the influence of water stress in the rainy and dry seasons on grain yield, biomass, harvest index and water use efficiency in the ‘Costela de Vaca’ cowpea variety cultivated in no-tillage system using crop residues present in the experimental area. Experimental design used was randomized blocks, in a 2 x 5 factorial scheme (cropping season x water stress), with four replicates. Treatments consisted of two cropping seasons (rainy and dry) and five forms of water stress (without water stress, water suspension for 5, 10 and 15 days, and rainfed cultivation). Biomass was the only parameter influenced by the cropping season versus water stress interaction. Regardless of the cowpea cropping season, water stress reduced grain yield and biomass. Harvest index showed no sensitivity to water stress and cropping season. Water use efficiency was influenced by the cropping season. Soil cover promoted maintenance of soil moisture during cowpea cultivation in both periods.

Evaluation of cowpea genotypes for resistance to the legume pod borer, Maruca Vitrata (Fabricius) (Lepidoptera: Pyralidae)

16 cowpea varieties were screened for resistance to the legume pod borer, Maruca vitrata F. under natural infestation in the field. Plants were planted in a randomized complete block design in three replicates; each plot consisted of four rows, 3m long. Spacing was 1.5m between plots and 0.75m between rows. Intra- row spacing was 0.2m.Two weeks prior to planting experimental materials, a susceptible cultivar was planted perpendicular to every range of rows within a plot to serve as a reservoir of the test insect, M.vitrata. Plants were sprayed with Monocrotophos at 200g a.i /ha once at the vegetative stage and at the onset of flower bud initiation and later during podding to control other pests apart from Maruca. Larval density, flower damage, pod damage, seed damage, pod load (a measure of the degree of successful pod production) and Index of pod evaluation (Ipe), calculated as [PL X (9-PD)], (a measure of the varietal performance of the cowpea genotypes) were used to assess resistance in cowpea varieties. Significant variations were observed in the level of resistance among the cowpea genotypes in the field. The findings show that Tvu 4578 is resistant while Tvu 1544, IT97K-499-35, IT93K452-1 and IT90K-76 show promising level of resistance. The probable factor contributing to resistance may be non- preference or host plant resistant factors.

Inferring multilocal typologies of agrosystems and farmers’ practices: A methodological basis for the setting of participatory breeding designs

Family farms play an essential role in agroecological transition in Sahelian countries and worldwide. They present diversified features in terms of socio-economic organization, agrobiodiversity management and cropping systems diversity. Decentralized participatory breeding approaches aim to sustain the diversity of varieties adapted for such smallholder farmers' contexts. However the lack of clear target population of environments limits the focus and the efficiency of these approaches given the large diversification of the local contexts. In this study, we surveyed variables linked to agrosystems, crop management options and farmers’ criteria of varietal evaluation from 254 family farms sampled along 13 locations spanning the target area of a decentralized participatory breeding program of cowpea crop (Vigna unguiculata L. Walp) in Niger. The objective of our study was to infer typologies of family farms in the study area based on relevant variables supporting the setting of target population of environments (TPEs) to be considered in the breeding program. We used factorial analysis of mixed data (FAMD) and the Discriminant Analysis of Principal Components (DAPC) to infer the clusters. Chi square test, analysis of variance and generalized linear model were used to identify key variables discriminating the clusters. These clusters were geographically mapped to analyze their multilocal distribution. So, we identified and characterized four clusters structuring the diversity of the local agrosystems (Typologie G), five clusters structuring the diversity of cowpea cropping management options (Typologie C) and five clusters structuring the diversity of criteria used by farmers to evaluate the performance of cowpea varieties in the local contexts (Typologie P). Typology G distinguished farms based on discriminating variables linked for instance to secondary activities, cultivated species, soil fertility management practices and farm resources including land and livestock. Typology C distinguished farms based on cowpea management pratices including the secondary crop intercropped with cowpea (sorghum, Guinea sorrel, sesame or groundnut) and the use of cowpea harvest products (seeds, haulms, hulls). Typology P was based on discriminating performance criteria including cycle length, insect resistance, striga resistance, drought resistance, haulm production and economic value of cowpea variety. This methodology provides a robust and replicable way for the definition of clusters capturing the diversity of farms and local contexts. We discussed the perspective of using these clusters to set target population of environments for decentralized breeding programs.

Importance of the Social Structures in Cowpea Varietal Demands for Women and Men Farmers in Segou Region, Mali

Cowpea is the second most consumed leguminous crop after groundnut in Mali. Its national production was 260,000 tons in 2018. It contributes to nitrogen fixation in the soil. The improved varieties of cowpea cultivars contain traits such as high grain yield, drought resistance, and early maturity. However, the adoption of improved cowpea varieties remains low. The non-participation and or non-consideration of the needs of men and women farmers in the varietal selection process contributed to the low adoption rate of improved cowpea varieties. This study aims to understand the gender dynamics and social structures within the communities. It examines its influence on the adoption of improved varieties of cowpea. Anchored on gender relations theories, gender and social structures are analyzed as the core frame for organizing social relations that guide and coordinate individuals’ actions in a given situation. Qualitative and quantitative approaches were applied to collect data from cowpea growers in 11 villages around the Cinzana Research Station. It emerged from the study that male farmers are quick adopters of newly released cowpea varieties because they are mainly more involved in trials, innovation platforms, field visits, demonstration plot activities, and FPVS than women. Women are less involved in these activities, except in sorting harvested cowpea grains and seeds in the Cinzana Research Station. Women’s participation in cowpea related-activities is determined by the rules and norms of physical mobility and the structures that control and guide social interactions and connections within and outside of households and communities. The study recommends efficient resource allocation within households and communities, and the set up of strong institutional frameworks (such as innovation platforms) to enable women in adopting new and improved cowpea varieties and to expand the available opportunities in the cowpea production system.

Bread Products from Blends of African Climate Resilient Crops: Baking Quality, Sensory Profile and Consumers’ Perception

With food insecurity rising dramatically in Sub-Saharan Africa, promoting the use of sorghum, cowpea and cassava flours in staple food such as bread may reduce wheat imports and stimulate the local economy through new value chains. However, studies addressing the technological functionality of blends of these crops and the sensory properties of the obtained breads are scarce. In this study, cowpea varieties (i.e., Glenda and Bechuana), dry-heating of cowpea flour and cowpea to sorghum ratio were studied for their effects on the physical and sensory properties of breads made from flour blends. Increasing cowpea Glenda flour addition from 9 to 27% (in place of sorghum) significantly improved bread specific volume and crumb texture in terms of instrumental hardness and cohesiveness. These improvements were explained by higher water binding, starch gelatinization temperatures and starch granule integrity during pasting of cowpea compared to sorghum and cassava. Differences in physicochemical properties among cowpea flours did not significantly affect bread properties and texture sensory attributes. However, cowpea variety and dry-heating significantly affected flavour attributes (i.e., beany, yeasty and ryebread). Consumer tests indicated that composite breads could be significantly distinguished for most of the sensory attributes compared to commercial wholemeal wheat bread. Nevertheless, the majority of consumers scored the composite breads from neutral to positive with regard to liking. Using these composite doughs, chapati were produced in Uganda by street vendors and tin breads by local bakeries, demonstrating the practical relevance of the study and the potential impact for the local situation. Overall, this study shows that sorghum, cowpea and cassava flour blends can be used for commercial bread-type applications instead of wheat in Sub-Saharan Africa.

Evaluation of Source and Sink Capacity of New Cowpea Varieties

Cowpea (Vigna unguiculata (L.) Walp) is a perennial species originating from sub-Saharan Africa. Cowpea has long been cultivated in Indonesia and is classified as a species tolerant of drought and acid soil. Cowpea shows its adaptation to acidic soil (pH = 4.83) by being able to produce 50% to 60% of the seed weight under optimum conditions. This enhances the potential of cowpea to be used and developed as one of the current food options. This research was carried out to optimise of cowpea productivity by studying the relationship between the source and sink of cowpea. This research was conducted from December 2020 to March 2021 at the Cikabayan experimental station, Bogor Agricultural University. The experiment was set up in a completely randomized block design. Four cowpea varieties were evaluated, “Albina”, “Arghavan”, and “Uno”. The measured parameters consisted of photosynthesis rate, stomatal conductance, plant growth rate, the net assimilation rate of the number of pods, pod weight, number of seeds per pod, dry seed weight, the weight of 100-seeds, and productivity. The cowpea varieties did not show significant differences in the rate of photosynthesis, stomatal conductance, plant growth rate, and net assimilation rate. Photosynthesis rate in the three cowpea varieties ranged from 29.20 to 31.77 mol. m⁻².s⁻1 at 50% flowering, and from 17.01 to 19.79 mol.m⁻².s⁻1 at the first harvest. The three cowpea varieties in this study showed no differences in their source-sink capacity and productivity.

Critical components and loss factors in inoculated and non-inoculated cowpea varieties grown in the Brazilian Amazon

The cowpea (Vigna unguiculata [L.] Walp) is of social and economic importance in developing countries. There are several factors that lead to low cowpea yields in tropical regions, such as pests and low technological development. This study aimed to identify and quantify losses in the critical component of production, and the key loss factors for three cowpea varieties (buttermilk, milk, and vinegar) grown in Santarém, Brazil, and inoculated or not with Bradyrhizobium japonicum. Crop life tables, loss factors, and production components of the three varieties were evaluated. Differences in yield and total losses were observed between varieties, but not between treatments with and without inoculant. In all three varieties, flowers were a critical component of production, and flower abortion was the key factor behind losses. Grain losses contributed significantly to total losses. The factors that contributed the most to grain component losses in all three varieties were malformation of grains and non-fertilisation of eggs. Inoculation increased losses through increased abortion of flowers in the buttermilk and milk varieties. Inoculation also increased damage caused to cowpea plants by cowpea weevils, Callosobruchus maculatus, in the buttermilk variety. Inoculation increased the total losses in the three varieties studied.

EVALUATION OF THE EFFICACY OF PLANT EXTRACTS (Cassia nigricans, Azadiracta indica and Carapa procera) AGAINST INSECTS (Aphis craccivora and Maruca vitrata) OF COWPEA IN A CROPPING SYSTEM IN MALI

Cowpea Vigna unguiculata L. Walpers (Fabaceae) is one of the main seed legumes produced and consumed in the world and particularly in West Africa precisely in Mali. In Mali, the cultivation of sorghum and cowpea in association occupies an important place in agriculture and contributes to achieving food and nutritional security in the country. Cowpea is an important source of vegetable protein. This crop is faced with many biotic (insects) and abiotic (drought) problems. The attack of pests (insects) can completely reduce the production of cowpea. Most farmers use chemicals to reduce these pests. While these chemicals (insecticides) have a negative impact on human health and that of the ecosystem. Aphids (Aphis craccivora) and Marucas (Maruca vitrata) can cause yield losses of up to 80%. Finding alternatives to synthetic pesticides is therefore a major challenge for the design of cropping systems. The study was carried out at the Sotuba agronomic research station for two years. Three varieties of cowpea (Sangaranka, djiguifa and Ghana Shoba) were planted in split plot in pure culture and in association with sorghum (Tiandougou coura). Three (3) products (Azadiracta indica and Cassia nigricans leaf, Carapa procera oil) and two controls (optimal K and without treatment) were used against Aphis craccivora and Maruca vitrata of cowpea. Observations focused on the number of Maruca vitrata and Aphis craccivora colonies before and after each treatment, the weight (pod, grain, haulm). The data was analyzed with GENSTAT Release 12.1 of the 12th edition of 2012. Zarama(Cassia nigricans) extract was the most effective among the others after the first treatment on Aphis and Maruca with a count average of 1.44 and 1.33 respectively of these two insects. The best grain yield was recorded in the same Sangaraka variety (1623 kg.ha-1) by treatment with Neem extract (Azadiracta indica), i.e. an increase of 8.1%.