Cowpea Vigna Unguiculata Research Articles

Effect of Microwave Radiation on Bacteria, Fungi and Some Growth Characteristics of Cowpea Vigna unguiculata L.

In this study, an experiment was conducted to describe the effects of using microwaves and chemical fertilization (isolated and combined) on the number of bacteria and fungi in the soil and on the growth of cowpea plants Vigna unguiculata L. Several times of exposure to microwave radiation (0, 25, 30, 35, 40, 45 s) and several concentrations of chemical fertilizer NPK (0, 0.9, 1.8 g 3 kg−1 soil) were carried out. After individual and combined treatments, experiments were carried out to quantify microorganisms (bacteria and fungi). In addition, 45 days after planting, analyzes were made of the cowpea plants for their development under different experimental conditions. The experiment was conducted in plastic pots to find out some characteristics of plant growth. The results indicated that the microwave sterilization resulted in the complete killing of bacteria and fungi and the fertilizer additive (NPK) to the soil had a critical role in increasing the values significantly for the number of root nodes and the remaining plant growth characteristics measured in this study.

Growth, nitrogen fixation and yields of cowpea (Vigna unguiculata L. Walp) and chemical properties of an acid Alfisol in response to applications of organic amendments and inorganic N

An acid Alfisol (Typic Paleustalfs) was amended in triplicates at the rate of 5 g kg−1 soil (12 t/ha) with organic amendment (cow dung (CD), corn cob (CC) and 1:1 CD:CC (CDCC), and 20 kg N ha−1 as urea, respectively, and planted to cowpea in the screenhouse. At flowering stage, plant shoots, roots and nodules were harvested. N2 fixed was estimated by N-difference method using maize planted and treated the same way as the cowpea as non-fixer. Considering average data for two planting periods, the increases (p < 0.05) obtained with the application of both organic manure with and without N over the control ranged from 125–775% for number of nodules, 96–296% for N2 fixed, 36–99% for dry matter yield and 160–460% for seed yield. The parameters were higher (p < 0.05) in the organic –inorganic N than in sole manure treatments. The organic amendments increased the pH, organic carbon (OC) and available P contents of the soil at both plantings, with CDCCN and CDCC recording the highest values. Average tissue N and P at the end of the two plantings were similar among all treatments, but average N and P uptakes were higher (p < 0.05) with than without amendments by 26–100% and 238–340%, respectively. Therefore, 5 g kg−1 cow dung:corn cob (1:1) or 5 g kg−1 cow dung in sole application or combined with 20 kg N ha−1 can promote cowpea growth, N2 fixation and yields with resultant positive effects on soil chemical properties.

Análise microbiológica do feijão caupi submetido a diferentes níveis de reposição hídrica com efluente doméstico tratado

Este trabalho teve como objetivo avaliar a qualidade microbiológica do feijão caupi (Vigna unguiculata) quando submetido a diferentes níveis de reposição hídrica em função da evapotranspiração da cultura (ETc) com três concentrações de efluente doméstico tratado. As plantas foram cultivadas em vasos dispostos em Delineamento de Blocos Casualizados (DBC) em esquema fatorial 3 x 4. A cultura foi submetida a quatro níveis de reposição hídrica (75, 100, 125 e 150% da ETc) com três concentrações de efluente doméstico tratado (0, 50 e 100%), com quatro repetições. Para a concentração correspondente a 0% foi utilizada água de abastecimento urbano, enquanto que nas concentrações de 50 e 100%, o efluente foi coletado da Estação de Tratamento de Esgoto da Universidade Federal de Sergipe. Foram avaliados: coliformes termotolerantes (NMP g-1) e Salmonella sp. Os resultados das amostras foram submetidos à análise de acordo com os parâmetros recomendados pela Resolução n° 12 de 02/01/2001 da Agência Nacional de Vigilância Sanitária - ANVISA. Os resultados demonstraram a ausência de Samonella, bem como de microrganismos indicadores de contaminação fecal nos grãos de feijão caupi, independente do tratamento utilizado.

Disease incidence and severity in cowpea lines evaluated for resistance to single and multiple infections of endemic viruses in Nigeria

ABSTRACT Cowpea (Vigna unguiculata (L.) Walp) is susceptible to several viruses in West Africa. Cowpea viral diseases are mainly controlled through the use of resistant cultivars. Co-infection with more than one virus is frequent in the fields and the resultant synergistic effect often compromises host resistance identified by screening against individual viruses under field or controlled conditions. In this study, eight improved cowpea breeding lines, identified as resistant to single infections and a susceptible cultivar (Ife Brown), were evaluated for their reactions to single and multiple infections of three viruses endemic in West Africa; viz., bean common mosaic virus-blackeye cowpea mosaic strain (BCMV-BlCM), southern bean mosaic virus (SBMV), and cucumber mosaic virus (CMV). Cowpea seedlings were inoculated with these viruses singly or in combination. Disease incidence and severity were recorded at weekly intervals for eight weeks. Virus infection was confirmed by enzyme-linked immunosorbent assay or reverse transcription-polymerase chain reaction. Systemic mosaic, vein-banding, and stunting were observed on inoculated plants. Mixed infection increased symptom severity and the highest severity was found in plants co-infected with CMV. Phenotyping against mixed-infections was more promising for estimating host resistance response in cowpea than single infections. Based on virus incidence and severity, lines IT97K-1069-6 and IT04K-405-5 were found to be resistant to SBMV, whereas IT99K-1060 and IT98K-503-1 were susceptible to the three viruses. IT-98 K-1092-1 was found to be resistant to BCMV and SBMV and tolerant to CMV under mixed inoculation scenario. Cowpea line IT-98 K-1092-1 is, thus, the best resistance source for use in virus resistance-breeding programs.

Effect of Arbuscular Mycorrhizal Fungi on Growth and Nutrient Status of Vigna unguiculata (L.)

Since last three decades, the increased use of chemical fertilizers in agriculture undoubtedly increased the food grain production and helped the country in achieving self-sufficiency in food grains. However, it also produced many harmful effects like water supply contaminations, shortage of quality of agricultural products and decrease in the amount of soil fertility. The study was performed to evaluate whether Arbuscular Mycorrhizal Fungi (AMF) improved Growth and Nutrient status in some important annual leguminous crops using Cow pea (Vigna unguiculate L) as a study material. Arbuscular mycorrhizal fungi (AMF) are important soil organisms belonging to phylum Glomeromycota and form symbiotic association with the roots of 70-90 % plant species. A pot experiment was conducted at Botanical Garden, School of Studies in Botany Jiwaji University Gwalior during the year 2019 to study the effect of arbuscular mycorrhizal fungi viz Glomus hoi and Acaulospora kentinensis on seed germination, growth and biochemical contents of cow pea Vigna unguiculata L. The Plants were raised in triplicates through the pot culture. The seeds were surface sterilized by hypochlorite solution before sowing. Pots were placed at a sunny place after the seed sowing. And after the seed germination, plants were irrigated when required. After germination the inoculated plants along with their controls was sampled. The results showed that Glomus hoi and Acaulospora kentinensis significantly increased growth parameters like root and shoot length, total leaf area, fresh and dry weight of roots and shoots in Vigna unguiculata L. Inoculation of Glomus hoi and Acaulospora kentinensis significantly increases the biochemical constituents like chlorophyll- a, chlorophyll-b, total chlorophyll, protein, carbohydrate, reducing sugar, non reducing sugar and total phenol. The present study pertains that AMF colonization improved positively the overall growth and development of cow Pea plant.

Mineral, organic, and organomineral fertilization associated with base saturation in Vigna unguiculata cultivation

ABSTRACT Eucalyptus spp. wood ash, as fertilizer, can be used for agriculture sustainability and the mitigation of production costs especially among small farmers who grow cowpea (Vigna unguiculata L.). The objective was to evaluate effects of fertilizers, mineral, organic (wood ash), and organomineral (organic+mineral) combined with base saturations of 30 or 60%, on growth and development of cowpea. Use of wood ash, alone and combined with mineral fertilizer, corrected soil acidity upward and increased shoot growth, nodule numbers, and water use efficiency. Wood ash may be an alternative fertilizer in cowpea production.

Development of SNP-based high-density genetic map and gene mapping of pod colour trait in Cowpea (Vigna unguiculata L. Walp.)

ABSTRACT The colour of fresh pods is one of the most important traits that affects the commercial value of cowpea (Vigna unguiculata) beans. To investigate the genetic architecture, we firstly scored the fresh pod colour of cowpea for six generations in field trials. Afterwards, an F2 population of 150 recombinant individuals was derived from crosses between two high-generation inbred cowpea lines, ‘Baojia’ (green pod colour, P1) and ‘Qilong’ (purple pod colour, P2). Ahigh-density genetic map based on 9,493 single nucleotide polymorphisms was constructed through SLAF sequencing and used for gene/s mapping of pod colour trait. We observed 59 single nucleotide polymorphism markers in one candidate gene region that may be associated with fresh pod colour trait located on LG6. The locus of pc was confirmed on chromosome 5 of the cowpea genome, which was corresponded to the genes encoding anthocyanin 5-aromatic acyltransferase and MYB-90 and MYB-114 domain proteins, that play important roles in the anthocyanin biosynthesis. Lastly, dCAPS markers were developed that explained the high rate of identification for the phenotypes of the F2 population. This study provides new knowledge of the genomic regions and will accelerate the genetic improvements, regarding the fresh pod colour (pc) trait in cowpea and marker-assisted selection.

EFFECTS OF CALCIUM HYDROGEN PHOSPHATE ON LEAD UPTAKE BY COWPEA (VIGNA UNGUICULATA)

The effects of calcium hydrogen phosphate on lead (Pb) uptake by cowpea (Vigna unguiculata) were investigated in a growth chamber experiment coupled with atomic absorption spectrophotometry (AAS) and colorimetry analyses. Cowpea seeds were planted and harvested in soil samples treated with Pb+2 added as lead nitrate at the rates of 0, 1000 and 3000 mg/kg followed by calcium hydrogen phosphate (CaHPO4) at 0, 10, 50 and 250 mg/kg. Increases in shoot yield brought about by phosphate fertilization were observed to oppress the shoot lead concentration as a result of growth dilution, where the actual amount of lead in shoots was unaffected by phosphate treatment. This work revealed that there is no substantial effect on lead uptake by cowpea, as a result of phosphate fertilization. Therefore, phosphate fertilization is a good means of cowpea production with minimal lead uptake and hence safe for human consumption

Effect of Seed Hardening and Pelleting on Growth, Yield, Physiology and Resultant Seed Quality of Cowpea under Natural Saline Conditions

Background: Cowpea (Vigna unguiculata) is one of the most important legume crops cultivated throughout the world. Cowpea is used as food, feed, forage, fodder, green manuring and vegetable. It’s seed is a nutritious component in the human diet, as well as for livestock. Seed hardening and pelleting are seed enhancement techniques used to improve seed germination and seedling vigour and growth by altering the physiological state of the seed. This alteration may improve the vigor or the physiology of the seed by enhancing uniformity of germination. Seed enhancement techniques like hardening and priming include use of chemicals that trigger systemic acquired resistance or improve stress tolerance whereas the pelleting treatments improve seed handling and planting. They also enhance nutrient availability or provide inoculates by delivering materials needed during sowing, germination and seedling establishment. Hence in order to study the combined effect of seed hardening and pelleting on growth, yield and resultant seed quality of cowpea under natural saline conditions, the present study was taken up. Methods: The present field and laboratory investigations were carried out to study the effect of seed hardening, seed pelleting and their combined effect on growth, physiology, yield and resultant seed quality of cowpea under natural saline conditions. The fresh seeds of cowpea seeds cv. CO (CP) 7 were hardened with KCl @ 1%, CaCl2 @ 1% and both KCl and CaCl2 @ 1% and then the hardened seeds were further pelleted with pungam leaf powder @ 100, 150 and 200 g kg-1 of seed. Then the treated seeds were evaluated for their seed productivity and resultant seed qualities using untreated seeds as control. Observations on growth, leaf chlorophyll content, gas exchange parameters, yield and resultant seed quality parameters were recorded. Result: The experimental results revealed that among the treatments, seeds hardened with KCl @ 1 % + CaCl2 @ 1 % and pelleted with pungam leaf powder @ 200 g per kg recorded higher growth, yield parameters, leaf chlorophyll content, gas exchange parameters and resultant seed quality when compared to control and other treatments.

Farmers’ perceptions, production constraints and variety preferences of rice in Tanzania

ABSTRACT Rice (Oryza sativa L.) is a major food and cash crop cultivated under diverse farming systems in Tanzania. The objective of this study was to assess farmers’ perceptions, production constraints, variety preferences and breeding priorities of rice in selected agro-ecologies in Tanzania to guide variety development and release. A participatory rural appraisal study was conducted involving 180 participants using a structured survey. Focus group discussions were held with 90 discussants in the Mvomero, Kilombero and Kyela districts of Tanzania. Survey results indicated that rice was the most important food and cash crop, followed by maize (Zea mays L.), cassava (Manihot esculenta Crantz), sweetpotato (Ipomoea batatas [L.] Lam.), sugarcane (Saccharum officinarum L.), pigeonpea (Cajanus cajan L.), cowpea (Vigna unguiculata [L.] Walp), simsim (Sesamum indicum L.), beans (Phaseolus vulgaris L.), cocoa (Theobroma cacao L.), banana (Musa acuminate L.), groundnuts (Arachis hypogaea L.), and palm (Elaeis guineensis Jacq.). Majority of respondents used saved seed from previous harvest. Major constraints limiting rice production and productivity in all studied areas were disease, insect pests, recurrent drought, non-availability and high cost of fertilizers, a lack of improved cultivars, poor soil fertility and bird damage. The farmers preferred rice varieties with high yield, disease resistance, drought tolerance, high market value, early maturity, aroma, and local adaptation. A systematic rice breeding program, aimed at improving yellow mottle virus resistance and incorporating farmers’ preferred traits, should be designed and implemented to increase productivity and adoption of new cultivars by the farmers across rice-growing areas of Tanzania.

Effect of biochar, lime and soil test value based fertilizer application on soil fertility, nutrient uptake and yield of rice-cowpea cropping system in an acid soil of Karnataka

A field experiment was conducted during Kharif and Summer seasons for two consecutive years of 2016-17 and 2017-18 with rice (Oryza sativa L.) and cowpea (Vigna unguiculata L.), grown in a sequence at Zonal Agricultural Research Station, Mandya on an acid soil to study the effect of biochar, lime and mangala setright on yield, nutrient uptake and fertility status of an acidic soil. Application of biochar along with soil test value based fertilizer (STV) + FYM + ZnSO4 influenced the productivity of rice and cowpea of 104.82 q ha−1 and 2474.77 kg ha−1, respectively and the uptake of nitrogen, phosphorus and potassium by rice (107.72, 28.16 and 69.34 kg ha−1, respectively) and cowpea (68.06, 5.86 and 38.67 kg ha−1, respectively) significantly, which was found on par with application of biochar along with RDF + FYM + ZnSO4. The soil pH (6.01), organic carbon content (5.03 g kg−1) and available nitrogen (340.45 kg ha−1), phosphorus (39.45 kg ha−1) and potassium (166.45 kg ha−1) significantly increased through the integrated use of biochar, FYM, ZnSO4 and fertilizers. Yield and soil properties like soil pH, organic carbon content and available nitrogen, phosphorus and potassium significantly increased with application of lime and mangala setright as compared to farmer’s practice. Highest net income and benefit:cost ratio (2.65) was obtained with integration of soil test value based fertilizer application, FYM and biochar. Significant reduction in the productivity of crop and soil fertility was recorded in farmer’s practice.

Population Development of Bean Weevils (Coleoptera: Chrysomelidae: Bruchinae) in Landrace Varieties of Cowpeas and Common Beans

Bean weevils (Coleoptera: Chrysomelidae: Bruchinae) are responsible for large quantity losses of cowpea (Vigna unguiculata (L.) Walp.; Fabaceae) and common bean (Phaseolus vulgaris L.; Fabaceae). The magnitude of damage is related to the grains’ varietal susceptibility. The objective of this study was to determine the population development rates of Callosobruchus maculatus (F.) (Coleoptera: Chrysomelidae) in 4 landrace varieties of cowpea (var. ‘UFAC-B01,’ ‘UFAC-MV01,’ ‘UFAC-MG01,’ and ‘UFAC-Q01’), as well as the population development rates of Zabrotes subfasciatus (Boheman) (Coleoptera: Chrysomelidae) in 4 landrace varieties of common bean (var. ‘UFAC-G01,’ ‘UFAC-M01,’ ‘UFAC-P01,’ and ‘UFAC-R01’). We determined the population development rates of the weevils in each variety. The weight of 100 grains (g) and the percentage of grain weight loss were measured, and correlations between these variables were analyzed. The statistical design was completely randomized, with 4 replications. Varieties UFAC-Q01 (cowpea) and UFAC-R01 (common bean) showed lower insect population development rates than other varieties. Although variations were found in the weight of 100 grains and grain weight loss, no significant correlations with bean weevil population development were observed. The cowpea and common bean landrace varieties from the southwestern Amazon region are important sources of resistance to bean weevils. The UFAC-Q01 cowpea variety and the UFAC-R01 common bean variety showed lower susceptibility to C. maculatus and Z. subfasciatus, respectively. Resumo Os bruquideos (Coleoptera: Chrysomelidae: Bruchinae) sao responsaveis por elevadas perdas na qualidade do caupi (Vigna unguiculata (L.) Walp.; Fabaceae) e feijao comum (Phaseolus vulgaris L.; Fabaceae), sendo que a magnitude dos danos esta relacionados a susceptibilidade varietal dos graos. O objetivo desta investigacao foi determinar as taxas de desenvolvimento populacional de Callosobruchus maculatus (F.) (Coleoptera: Chrysomelidae) em quarto variedades crioulas de caupi (var. ‘UFAC-B01,’ ‘UFAC-MV01,’ ‘UFAC-MG01,’ e ‘UFAC-Q01’), bem como a a taxa de desenvolvimento populacional de Zabrotes subfasciatus (Boheman) (Coleoptera: Chrysomelidae) em quarto variedades crioulas de feijao comum (vbean weevilsar. ‘UFAC-G01,’ ‘UFAC-M01,’ ‘UFAC-P01,’ e ‘UFAC-R01’). Foram realizados bioensaios para determinar as taxas de desenvolvimento populacional dos bruquideos em cada variedade, e avaliou-se a massa de 100 graos (g), perda de massa (%) e foram realizadas analises de correlacao entre estes fatores. O delineamento estatistico foi inteiramente casualizado com quatro repeticoes. As variedades UFAC-Q01 e UFAC-R01 de caupi e feijao comum, respectivamente, apresentaram menores taxas de desenvolvimento populacional, comparando-se com as demais variedades. Embora tenha havido variacao da massa de 100 graos, perda de massa, nao foram constadas correlacoes significativamente com o desenvolvimento populacional dos bruquideos. As variedades landraces de caupi e feijao comum, oriundos da Amazonia Sul-Ocideltal, constituem importantes fontes de resistencia para bruquideos, sendo que as variedades UFAC-Q01 e UFAC-R01 de caupi e feijao comum apresentaram menor susceptibilidade ao ataque de C. maculatus e Z. subfasciatus. Key Words: Vigna unguiculata; Phaseolus vulgaris; varietal susceptibility; storage; bruchids View this article in BioOne

Effect of Seed Hardening and Pelleting on Germination and Seedling Attributes of Cowpea under Saline Condition

Cowpea (Vigna unguiculata) is an important legume crop. Investigations were undertaken to study the effect of seed hardening, seed pelleting and combined effect of seed hardening with seed pelleting on germination and seedling growth of cowpea under induced saline condition viz., EC4, EC8, EC12 and EC16. Cowpea seeds were hardened with KCl @ 1%, CaCl2 @ 1% and both KCl and CaCl2 @ 1% and hardened seeds were further pelleted with pungam leaf powder @ 100, 150 and 200 g kg-1 of seed. Observations on germination % and seedling parameters were recorded. The experimental results revealed that increased salinity reduced germination and seedling growth in terms of germination %, speed of germination, root length, shoot length, dry matter production and vigour index. However, hardening and pelleting treatments significantly increased all these parameters at all the levels of salinity when compared to control. Among the treatments, seeds hardened with KCl @ 1 % + CaCl2 @ 1 % and pelleted with pungam leaf powder @ 200 g per kg recorded higher germination % and all the seedling parameters when compared to control and other treatments.

Influence of Inorganic Fertilizer (NPK 15:15:15) and Cacao (Theobroma cacao L) Leaf Litter Application Rates on Cowpea (Vigna unguiculata L.) Performance in the Tropics

Influence of inorganic fertilizer (NPK 15:15:15) and cacao (Theobroma cacao L.) leaf litter application rates on cowpea (Vigna unguiculata L.) performance in the tropics was studied for 24 months (January, 2017 – December, 2018) at Cocoa Research Institute of Nigeria (CRIN) Ibeku Sub-Station, Umuahia, Nigeria. Three 3 x 3 factorial experiments, each in a Randomized Complete Block Design (RCBD) with three replicates/blocks were used to study the responses of cowpea to three NPK 15:15:15 fertilizer rates 0 kg, 500 kg and 1000 kg ha-1 represented by (Factor F) F0, F1 and F2, respectively, and cocoa leaf litter rates 0 t, 10 t and 20 t ha-1 which were also represented by Lo, L1 and L2 (Factor L), respectively. The results obtained from the study show that the application of either 10 or 20 t ha-1 cocoa leaf litter alone or complementary application of either 10 or 20 t ha-1 cocoa leaf litter plus 500 or 1000 kg ha-1 NPK 15:15:15 fertilizer significantly increased the various cowpea growth and yield components than the fertilizer rates alone. The treatment without fertilizer and leaf litter, i.e. topsoil only (F0L0) gave significantly the least cowpea growth and yield components. The highest values were obtained with the application of 1000 kg ha-1 NPK 15:15:15 fertilizer with 20 t ha-1 cocoa leaf litter (F2L2). The cowpea crop performance in terms of growth, yield and yield components over the study periods, 2017 and 2018 were statistically similar. Therefore, the inclusion of leaf litter has greater potential for improving cowpea yield than when fertilizer was used alone. Leaves are potential sources of valuable nutrients providing a high quality of organic matter, which should be returned to the soil.&#x0D;

Native Bradyrhizobium Strains From Ghana Can Enhance Grain Yields of Field-Grown Cowpea and Groundnut

The existence of large population of ineffective native rhizobia and inconsistent performance of exotic strains in Ghanaian soils necessitate the need to identify effective and locally adapted elite strains for enhanced legume-rhizobium symbiosis. This study was designed to test the suitability of two previously selected potential elite Bradyrhizobium strains for use as inoculants on cowpea (Vigna unguiculata L. Walp) and groundnut (Arachis hypogaea L.) in multi-location experiments. Field experiments were set up at 26 locations (12 planted with cowpea and 14 planted with groundnut) in the Northern region of Ghana. Four treatments were applied at each location: inoculation with Bradyrhizobium strains KNUST 1002 and KNUST 1006, a positive nitrogen (+N) control and a negative control (without nitrogen or inoculation) arranged in randomized complete blocks with four replications. The results showed that inoculation with strains KNUST 1002 and KNUST 1006 promoted significant increases in grain yields of both cowpea and groundnut. On average, inoculating cowpea with strains KNUST 1002 and KNUST 1006 resulted in 63 and 52% increases in grain yield when compared to the negative control. Pod yields of groundnut on the other hand, were significantly (p< 0.05) increased at 57% of the study location with one or both test strains. Responses to inoculation were, however, highly variable across the different study locations (i.e. significant Treatment ⸼ Location Interaction, TLI). A detailed analysis of this significant TLI based on the genotype main effect (G) plus genotype-by-environment (GE) interaction (GGE) biplot analysis revealed that location contributed 71 and 88% of the variation observed in cowpea and groundnut, respectively, and grouped the locations into mega-environments. These results demonstrate that native elite Bradyrhizobium strains KNUST 1002 and KNUST 1006 have potential for use as inoculants to increase cowpea and groundnut production in Northern Ghana.

Protein Content and Seed Trait Analysis in a Subset of the USDA, ARS, PGRCU Cowpea [Vigna unguiculata (L.) Walp.] Core Collection

Cowpea (Vigna unguiculata (L.) Walp is used as a vegetable and feedcrop worldwide, but knowledge is limited regarding the variability and correlations for protein and seed traits within a cowpea core collection. We analyzed protein content and seed trait data from the cowpea core collection representing 111 accessions. The accession PI 354729 produced the significantly highest protein content of 25.527%. Eight Indian cowpea accessions produced significantly high protein content averaging 24.423%. Protein content was significantly correlated with seed pattern (r2 = 0.274***), seed texture (r2 = 0.346***), seed coat color (r2 = 0.136*) and seed pattern significantly correlated with seed texture (r2 = 0.197**). However, protein content showed a significant negative correlation (r2 =-0.333***) with 100 seed weight. One hundred seed weight (gm) showed significantly negative correlations with seed pattern (r2 = -0.191**) and seed texture (r2 = -0.265***). Seed coat color showed a significant negative correlation with seed pattern (r2 = -0.14). Based on these results, potential cowpea cultivars could be developed with improved protein content and morphological seed traits.

Effects of green manure legumes and their termination time on yield of maize and soil chemical properties

ABSTRACT A two-year field experiment was conducted to examine the effects of interseeded green manure (GM) legumes in maize (Zea mays L.) cropping systems and their termination time on yield of maize and soil chemical properties in southern Ethiopia. Maize variety, BH540 was planted as the main crop while three GM legumes cowpea (Vigna unguiculata L. Walp), lablab (Lablab purpureus (L.) Sweet) and hairy vetch (Vicia villosa Roth) were interseeded between maize rows. The GM legumes were terminated and incorporated into soils at 30, 45 and 60 days after planting. The amounts of dry biomass produced varied significantly (p < 0.05) among GM legumes and their termination time. The results indicated that GM legumes accumulated over 39.3–65.5 kg N ha−1 yr−1 during 2014 cropping season and 53.3–156.6 kg N ha−1 yr−1 during 2016 cropping season. However, maize stover and grain N yields were not significantly influenced by GM. The results suggest GM legumes, lablab and cowpea improved soil chemical properties (N, P and K). Therefore, interseeding and incorporation of GM legumes can be considered as an alternative mechanism of soil fertility management for sustainable crop production in southern Ethiopia, where rotational and successional GM legumes cultivation is practically impossible.

Performance Evaluation of a Cowpea Thresher at Various Moisture Contents

To improve the quality of threshed cowpea (Vigna unguiculata L.), produced by rural farmers in Ghana, and determine the best machine-crop parameters combination for optimum performance, a cowpea thresher was developed and evaluated at different moisture contents. The cowpea after harvesting was divided into five units and dried to 20.7, 18.4, 15.5, 13.5 and 12.6 % seed moisture contents. The effect of seed moisture contents on threshing quality was assessed at 735 rpm rotor speed using the white with black eye cowpea. The performance test showed that 12.6 % had the highest throughput of 77.56 kg/h with the lowest of 66.28 kg/h from the 20.7%. The seed damage ranged from 1.64 to 9.46 % and threshing efficiency from 93.11 to 99.40 %. Analyses done at 5% level of significance indicated no significant difference in the throughput and threshing efficiencies. However, seed damage had significant difference. Subsequently, analysis performed on the data for seed loss of 12.6 and 13.5 % which were the best performing moisture contents showed no significant differences. Therefore, seed moisture contents less than 13.5 % and rotor speeds less than 735 rpm are the crop- machine parameters combination for optimum thresher performance.&#x0D; &#x0D; &#x0D; &#x0D; Key words: Design; Throughput; Impact Force; Seed Loss; Simulation&#x0D; &#x0D; &#x0D;

Nitrogen transfer from green manure to organic cherry tomato in a greenhouse intercropping system

This work aimed to evaluate the nitrogen transfer, the yield and the nutrient contents of organic cherry tomatoes intercropped with legumes in two successive years. The randomized block experimental design was used with eight treatments and five replicates, as follows: two controls with single cherry tomato crop (with and without corn straw cover); cherry tomato intercropped with jack bean (Canavalia ensiformis DC); white lupine (Lupinus albus L.); sunn hemp (Crotalaria juncea L.); velvet bean-dwarf [(Mucuna deeringiana (Bort) Merrill)]; mung bean (Vigna radiata (L.) Wilczek), and cowpea (Vigna unguiculata (L.) Walp). The number of total fruits, the weight of total fruit and an average weight of the total fruit in the first year was 25%, 33% and 13% higher than the second-year, respectively. The lower N-content of cherry tomato leaves in the treatment with mung bean can be reflected of lower %N transfer of cherry tomato leaves in the same treatment compared to treatment with cowpea bean. The N-content and %N transfer of cherry tomato leaves was 50 and 42% higher in year 1 than in year 2, successively. Nevertheless, in general, the legumes used in this study contributed equally in the N transfer to the cherry tomato plants. The P, K, Mg, Ca, Cu, Mn, Fe and Zn content in the leaf and shoot were no difference between the treatments. However, the Mg, Ca, Cu, Fe, Mn and Zn content of the leaf were higher in year 2 than year 1.

Performance of pearl millet [Pennisetumglaucum (L.)R. Br.] varieties intercropped with cowpea varieties as affected by planting dates in Nigerian Sudan savanna

Field experiments were conducted in 2015 and 2016 rainy seasons at the Teaching and Research Farm of the Department of Crop Production, University of Maiduguri, Maiduguri (11047N; 12016E) to study the performance of pearl millet varieties (Pennisetum glaucum) (L.) R. Br.) intercropped with cowpea (Cowpea Vigna unguiculata (L.) Walp) varieties under different planting dates. The treatments consisted of three pearl millet varieties: ZATIP, SOSAT-C-88 and LACRI-9702-IC, two cowpea varieties: Borno Brown and SAMPEA 11 and four planting dates: 0 weeks after planting millet (WAPM), 1 WAPM, 2 WAPM and 3 WAPM. The experimental design was Split-Split plot with the pearl millet varieties allocated to the main plots, cowpea varieties assigned to the sub-plots and planting date assigned to the sub- sub plots in 1:1 alternate row arrangement, and replicated three times. The results showed that in 2015, 2016 and the combined mean, number of tillers/plants, harvest index and grain yield/hectare were significantly greater for SOSAT-C-88 than ZATIP or LACRI-9702-IC. Plant height, panicle were significantly greater for ZATIP, while, yield/hectare were significantly greater for Borno Brown than SAMPEA 11 variety. Delaying planting date by three weeks after planting the millet component decreased grain yield and fodder yield in cowpea. The land equivalent ratio of pearl millet and cowpea variety showed that, higher partial land equivalent ratio were produced by SOSAT-C-88 + Borno Brown. The partial land equivalent ratio of pearl millet variety for straw yield and grain yield advantages were higher for LACRI-9702-IC + cowpea intercrop. From this study, the millet variety SOSAT-C-88 intercropped with cowpea variety Borno Brown is ideal for both staple grain and cash returns from the system in the Sudan Savanna of Nigeria.