Cowpea Seeds Research Articles

Physiological quality of cowpea seeds after application of chitosan-based bioproduct

The use of biological methods in the agricultural field has instigated studies in the development of products based on biopolymers. Chitosan is a biopolymer and important alternative to the agrochemicals used in large cultures, presenting favorable characteristics to the development of the plants, to the environmental issues, and to the agricultural sector economy. Therefore, the present study aimed to evaluate the effect of the application of a chitosan-based bioproduct in the germination and vigor of cowpea seeds. A completely randomized design was adopted with four replications of 50 seeds, with the exception of the mass and length tests, carried out in five replications of 20 seeds. The chitosan-based product was tested in the concentrations of 0.0 (witness); 0.5; 1; 2.5; 5; and 10% and physiological quality parameters, emergency, vigor, leaf pigments contents and electrolyte extravasation were evaluated. The results indicated that the treatments coated with the bioproduct significantly increased the length of the seedling, shoots and radicle, shoot and seedling fresh masses, and seedlings dry mass emerged in a bed. We concluded that the application of the bioproduct, at FTSeed concentrations at 3 and 3.25%, as a coating in cowpea seeds induced the seedlings growth, acting as a biostimulant. The principal component analysis (PCA) showed a correlation between biochemical tests and germination potential in the field, with emphasis on the 5% treatment.

The Effect of Selenium Sources and Rates on Cowpea Seed Quality

Selenium (Se) is a beneficial element for plants and is essential for human nutrition. In plants, it plays an important role in the formation of selenocysteine and selenomethionine and in the activation of hydrolytic enzymes, which can aid in seed germination and reduce abiotic stress during germination. The objective of this study was to evaluate the effects of the application of selenium sources and rates to the soil on the physiological quality of cowpea seeds. The experimental design was a randomized block with four replications and a factorial scheme (7 × 2). Two sources of Se (sodium selenate and sodium selenite) and seven rates (0, 2.5, 5, 10, 20, 40 and 60 g ha−1) were used. Physiological characterization was carried out by first counting of germination, germination, emergence, accelerated aging, cold testing, electrical conductivity, length and dry biomass of shoots and roots. Germination after accelerated aging increased with selenate, even at higher rates, whereas selenite provided benefits at lower rates. Selenation linearly increased germination after the cold test and linearly reduced electrolyte leakage as the Se rate increased. The soil application of Se is beneficial for cowpea seed quality. Compared with those treated with sodium selenite, cowpea plants treated with sodium selenate through the soil produce more vigorous seeds. The application of 10 g ha−1 Se in the form of sodium selenate provides seedlings with faster germination and root development and is an alternative for rapid stand establishment.

The Influence of Biological Factors on Inhibiting Fusarium oxysporum, the Causal Agent of Fusarium Wilt in Cowpea Plant

This study was conducted for the agricultural season 2023-2024 with the aim of evaluating the efficiency of bio agent of Bacillus cereus, Trichoderma Longibrachiatum and Saccharomyces cerevisiae on Cowpea plants infected with Fusarium wilt disease in pots. Three isolates R2, R3 and R7 of Fusarium oxysporum were isolated from the roots of Cowpea plants that showed symptoms of wilt. The isolated fungi were diagnosed morphologically and partially. The results of molecular diagnosis of the fungi showed 100% matching of the isolates. Pathogenicity tests were conducted on cowpea seeds in the laboratory using Petri dishes containing W.A medium as a pathogen for cowpea plants, as the germination percentage of cowpea seeds for all isolates reached 76.66, 66.66 and 63.66% compared to the control treatment which reached 100%. The results of the pot experiment showed that there were no significant differences in the infection severity by the pathogenic fungus in the three isolates, as R2 reached 82.00, R3 82.00 and R7 87.33% respectively compared to the control treatment which reached 0.00%. The results of the pot experiment indicated the effect of bio agent in increasing some plant growth indicators and reducing the infection severity which reached 0.00% in the T. Longibrachiatum, B. cereus and S. cerevisiae treatments. It was also noted from the results that the highest germination rate of cowpea seeds was in the yeast S. cerevisiae treatment, which reached 96.00% compared to the control treatment, which reached 100%. The results of chlorophyll estimation indicated that the treatment of the biological fungus T. Longibrachiatum and the yeast S. cerevisiae was similar to the control treatment, which reached 0.82 mg/g¯¹.

Effect of Gamma Irradiation on Nutritional Quality and Shelf Life of Cowpea (Vigna unguiculata) Produced in Benue State Nigeria

Cowpea plays an important role in the lives of millions of people in the developing world, providing a major source of dietary protein that nutritionally complements low-protein cereal and tuber crops. However, during storage, cowpea is attacked by a number of biological agents, which result in losses in the quality and quantity of stored seeds. This research investigated the application of Cobalt-60 gamma irradiation on the proximate composition and shelf life of locally produced cowpea seeds in Benue State, Nigeria. Cowpea seeds were irradiated at doses of 200 Gy, 300 Gy, 400 Gy, and 500 Gy and stored for four months. Proximate analysis revealed no significant difference (p ≥ 0.01) in protein, fat, ash, crude fibre, and carbohydrate content between irradiated cowpea seeds and the control. However, a significant difference (p ≤ 0.01) was observed in moisture content across all doses. After four months of storage, weight loss analysis indicated significant differences between irradiated and non-irradiated seeds of cowpea. Control samples experienced greater damage from insect infestation, resulting in the highest percentage of weight loss compared to irradiated samples. Notably, 500 Gy exhibited the least weight loss among irradiated samples, highlighting a dose-dependent effect of gamma irradiation on weight loss and its potential impact on shelf life. Irradiation doses, of 500 Gy for cowpea, can effectively preserve the nutritional components and extend the shelf life of cowpea, offering an alternative to chemical preservation methods.

Impact of Live Mulch, Brown Manuring and Herbicides on Growth and Yield of Sorghum (Sorghum bicolor (L.) Moench) in Southern Midland Zone of Kerala, India

A field experiment was conducted during the rabi season of 2023 at the Farming System Research Station, Sadanandapuram, Kerala, to evaluate the effects of live mulch, brown manuring and herbicides effect as weed management method on growth and yield of sorghum. The experiment was conducted in a randomized block design with ten treatments, replicated thrice. The treatments included: Broadcasting cowpea seeds @ 15 kg ha -1 fb live mulch at 25 DAS, Broadcasting cowpea seeds @ 30 kg ha -1 fb live mulch at 25 DAS, Broadcasting cowpea seeds @ 15 kg ha -1 fb brown manuring with 2,4-D 1 kg ha-1 at 20 DAS, Broadcasting cowpea seeds @ 30 kg ha -1 fb brown manuring with 2,4-D 1 kg ha-1 at 20 DAS, PE pretilachlor 0.75 kg ha-1fb one HW at 25 DAS, fenoxaprop-p-ethyl 0.06 kg ha-1 at 20 DAS, T7:PoE 2,4-D 1 kg ha-1 at 20 DAS, HW at 20 DAS, Weed free control and Weedy check. Among the treatments, broadcasting cowpea seeds at 30 kg ha⁻¹ followed by live mulch at 25 DAS (T2) resulted the higher growth parameters, including plant height, number of leaves per plant, and dry matter production at 45 DAS and harvest. Leaf area per plant and leaf area index were also significantly higher in T2 at 30 and 45 DAS. Yield attributes, such as panicle length, number of grains per panicle, grain weight per panicle, grain yield, stover yield and harvest index were higher in T2. Broadcasting cowpea seeds @ 30 kg ha -1fb brown manuring with 2,4-D 1 kg ha-1 at 20 DAS, pre-emergence pretilachlor 0.75 kg ha⁻¹ fb hand weeding at 25 DAS, post-emergence fenoxaprop-p-ethyl 0.06 kg ha⁻¹ at 20 DAS and weed free control performed statistically comparable with T2 in terms of growth and yield attributes.

Effect of Bacillus licheniformis on Growth, Bone Mineralization, and Intestinal Microbiota in Broilers Fed Cowpea Diets

This study investigates the effects of the Bacillus licheniformis (BL) ATCC 21424 strain, as a potential bacterial probiotic in broiler diets based on soybean meal (SBM) or cowpea seeds (CWP), on growth performance (GP), bone mineralization, and intestinal/fecal microbiota status (0 to 42 d age). A 2 × 2 factorial arrangement was employed in a completely randomized design, with four dietary treatments: SBM and CWP diets with or without BL supplementation (1.0 × 1011 CFU spores g−1 feed). A total of 480 one-day-old mixed-sex Ross 308 broiler chickens were randomly assigned to the treatments, with 6 pens of 20 chicks each. The results showed that broilers fed with CWP diets showed comparable body weight gain (BWG), feed intake (FI), and feed conversion rate to those fed the SBM diet (p > 0.05). The inclusion of BL improved BWG during the grower and finisher periods (p = 0.01) and overall study (p < 0.001), resulting in a numerical increase in FI (p = 0.054). In addition, BL in birds’ diets reduced abdominal fat (p = 0.032) and influenced cecum weight (p = 0.040). Additionally, BL improved tibia iron (Fe) and phosphorus (P) bone mineralization and reduced the calcium–phosphorus (Ca:P) ratio (p = 0.0001). Microbial analysis revealed that BL inclusion decreased Coliforms counts in the CWP diet (p = 0.073), reduced E. coli in the ileum (p ≤ 0.05), and lowered Clostridium spp. and Enterococcus spp. in the cecum broilers on SBM diets (p ≤ 0.05). The presence of Staphylococcus spp. in broiler feces was also reduced in both SBM and CWP groups (p < 0.05). In conclusion, the addition of BL to broiler diets enhanced growth performance and bone mineralization and positively influenced gut and excreta bacterial populations in both SBM and CWP diets.

Fungicidal Potentials of Leaf and Bark Extracts of Bryophyllum pinnatum on Cowpea (Vigna unguiculata L.) Seed Fungi

In Nigeria, Cowpea (Vigna unguiculata [L.] Walp) is an important grain legume which besides being a food crop serves as a major source of income for rural households. The action of pathogens on stored seeds causes huge post-harvest and economic losses to cowpea farmers in Nigeria. This research was aimed at isolating and identifying the spoilage pathogens of cowpea seed and testing the potentiality of ethanol extracts of Bryophyllum pinnatum on the isolates. Spoilt cowpea seed samples were purchased from different markets in Anambra State. They were transported to Alpha Research Laboratory, Awka in sterile polythene bags for microbial isolation. The spoilage organisms were isolated from the seeds through microbial culture. The media used for the isolation were Sabouraud Dextrose Agar and Potato Dextrose Agar. Pathogenic fungi were isolated from the spoilt cowpea seeds. The findings indicated that Aspergillus aculeatus, Fusarium solani, Penicillium citrinum, Rhizopus stolonifer, and Aspergillus flavus were present. The pathogenicity test also showed that the above organisms were responsible for cowpea spoilage. These isolates were tested for their in-vitro antifungal activity against the leaf and bark extracts of Bryophyllum Pinnatum. The antifungal activity ethanol extracts of Bryophyllum pinnatum on the isolated microorganisms were investigated using the disc method. Three different concentrations (25%, 50%, 100%) of extracts were used for the test. Fusarium solani showed the highest percentage of inhibition with antifungal medication while Penicillium citrinum showed the least percentage of inhibition with antifungal medication. The antifungal potential of Bryophyllum pinnatum extract on spoilage pathogens of stored cocoyam corms encourages more research on the active ingredient of the plant for easy use by farmers as alternative to commercial/ synthetic fungicides.

Hand Warmer-Induced Hypoxia Accelerates Pest Control in Hermetic Storage.

Accelerating oxygen depletion during hermetic storage can minimize pest damage and preserve product quality. This study evaluated the effectiveness of hand warmers in accelerating hypoxia to control insect pests inside hermetic containers. We used one, two, or four hand warmers to deplete oxygen in a 4-gallon hermetic jar with 4 kg of cowpea and cowpea bruchids, alongside a non-hermetic control with cowpea bruchids and no hand warmers. Oxygen levels, insect mortality, egg counts, seed moisture content, and germination rates were monitored over 2, 5, or 8 days of storage. Only the four hand warmers treatment reduced oxygen levels below 1% within 12 h and maintained them for up to 168 h. The other treatments did not achieve this level. Insect mortality was higher with more hand warmers and extended storage duration, reaching 100% after 5 and 8 days with four and two hand warmers, respectively. Similarly, increased hand warmers and extended storage durations reduced egg counts and adult emergence. The treatments did not affect the moisture content or germination rates of the stored cowpea seeds. Hand warmers proved effective in accelerating hypoxia during hermetic storage, resulting in high insect mortality and reduced reproduction, without compromising grain quality.

Biochar addition influences C and N dynamics during biochar co-composting and the nutrient content of the biochar co-compost

This study investigated the effects of corn cob biochar (CCB) and rice husk biochar (RHB) additions (at 0%, 5%, and 10% w/w) on nitrogen and carbon dynamics during co-composting with poultry litter, rice straw, and domestic bio-waste. The study further assessed the temperature, moisture, pH, and nutrient contents of the mature biochar co-composts, and their potential phytotoxicity effects on amaranth, cucumber, cowpea, and tomato. Biochar additions decreased NH4+-N and NO3- contents, but bacteria and fungi populations increased during the composting process. The mature biochar co-composts showed higher pH (9.0–9.7), and increased total carbon (24.7–37.6%), nitrogen (1.8–2.4%), phosphorus (6.5–8.1 g kg−1), potassium (26.8–42.5 g kg−1), calcium (25.1–49.5 g kg−1), and magnesium (4.8–7.2 g kg−1) contents compared to the compost without biochar. Germination indices (GI) recorded in all the plants tested with the different composts were greater than 60%. Regardless of the biochar additions, all composts treatments showed no or very minimal phytotoxic effects on cucumber, amaranth and cowpea seeds. We conclude that rice husk and corn cob biochar co-composts are nutrient-rich and safe soil amendment for crop production.

Effects of priming duration and rhizosphere bacteria metabolite concentration on the germinability of cowpea, soybean, sesame, and okra seeds

Seed priming enhances germination and growth, which are important determinants of crop yield. This study was carried out to assess the effect of priming duration and metabolite concentration on the priming of five (5) crops using the metabolites of five (5) bacterial isolates. The crop seeds were treated in the cold-extracted metabolites of the five isolates at five (5) different priming durations (1, 2, 3, 4, and 5 h) and then in five metabolite concentrations (200, 400, 600, 800, and 1000 mg/L) of the five extracted metabolites at the optimal priming duration determined in the first experiment. Characterization of the cold-extracted metabolites was also carried out using gas-chromatography-mass spectrometry (GC-MS). Results revealed that priming cowpea and soybean seeds for longer durations (< 3 h) could hinder their growth and development. Lower concentrations were observed to be optimal for cowpea and soybean, but for sesame and okra, there was no detectable pattern with metabolite concentration. The GC-MS revealed the presence of some molecules (e.g. hexadecanoic acid) that have shown plant growth promotion potential in other studies. This study showed that seeds with large endosperms, such as those of cowpea and soybean, are more prone to the harmful effects of treatment for longer durations. Further experiments should be undertaken to isolate and purify the bioactive moieties for further studies and application.

Evaluation of three inert materials in controlling Cowpea weevil (<em>Callasobruchus maculatus</em> F.) on stored cowpea (<em>Vigna unguiculate</em> L.)

Eco-friendly inert materials can be achieved minimizing insect damages, this study was conducted to explore the efficacy of the three inert materials at 20% (w/w) paddy husk ash (PHA), fine dry sea salt and tiny bricks against the cowpea weevil C. maculatus on stored cowpea (V. unguiculata) on the basis of adulticidal effects and asses the influence against germination losses of the seeds. The result exhibited a significant difference (p≤ 0.0001) in their level of weevil attack during the storage. Maximum 100% adult mortality was recorded in the cowpea seeds incorporated with PHA after 96 hours of the treatment followed by dry salt it was observed 94% at the 5th day whereas, tiny bricks killed only 20% weevils as untreated control until 5th day after the treatment. Further, PHA treated seeds much reduced the capable of the egg laying capacity of weevil (9.8± 0.58eggs/ female) as well as minimized the production of new progenies (13.6 ± 0.37) and also there were recorded 0.03% weight loss and zero percent germination losses proving it to be best protectant on stored cowpea. However, significantly (p≤ 0.0001) any adverse effects that, egg laying capacity and new progeny production did not visible in dry salt up to 90 days after the treatments except minimize the germination loss. Among the inert materials used, tiny bricks were found ineffective to cause adult mortality, fecundity and adult emergency in F1 generation (119.8± 1.78), it was further increased production of new weevils obtained following the next F2 generation (1301 ± 0.65) and play down the losses of weight and germination of the seeds. Considering it was noticed tiny bricks treated seeds significantly equivalence with the level of damage by the weevil C. maculatus in untreated control on stored cowpea.

Isolation, Purification and Identification of Fungi Associated with Cowpea Seeds, Vigna unguiculata (L.) and the Possibility of Their Resistance Using Some Biological Techniques

Isolation, Purification and Identification of Fungi Associated with Cowpea Seeds, Vigna unguiculata (L.) and the Possibility of Their Resistance Using Some Biological Techniques

Animal pollination shapes fruits market features, seeds functional traits and modulates their chemistry

In this study, we experimentally addressed the impact of different pollination treatments on the morphological, reproductive and chemical traits of fruits and seeds of two crop species, the wild strawberry (Fragaria vesca L.) and cowpea (Vigna unguiculata (L.) Walp.). Multiple flowers from each plant were exposed to different pollination treatments: (1) self pollination, (2) hand cross pollination and (3) open pollination. Both crops were positively affected by open pollination in terms of morpho-chemical parameters concerning the marketability (e.g., 35% decrease in sugar/acid ratio in open pollinated strawberries compared to the autogamous ones) and the seed germination rate as a proxy of reproduction efficiency (e.g., the almost complete absence of seed abortion in the open pollination treatment). Remarkably, the pollination treatment also strongly influenced the phytochemical composition. Open-pollinated strawberries exhibited a higher relative concentration of compounds endowed with nutraceutical properties such as anthocyanins, ellagic acid derivatives and flavonoids. At the same time, cowpea seeds displayed higher concentrations of anti-nutrients in the self pollination treatments, such as saponins, compared to the open and hand cross pollinated seeds. This study suggests the presence of a link between the pollination mechanism, market quality, plant reproduction and chemical properties of fruits and seeds, supporting the intricate interplay between pollinators, plants and human nutrition, highlighting the crucial importance of animal pollination in the ecological and dietary contexts.

INVESTIGATION OF COMBINED EFFECT OF THREE PLANT POWDERS WITH DIATOMACEOUS EARTH AGAINST CALLOSOBRUCHUS MACULATUS

The study was conducted to investigate the combined effects of various plant powders and Silico-sec, a diatomaceous earth, on Callosobruchus maculatus at the research laboratory of the Department of Crop Pest and Soil Management, the Federal University of Technology, Akure. The study included three replications. The treatments consisted of three (3) plant materials derived from the dry flower buds of Eugenia aromatica, seeds of Piper guineense, and leaves of Nicotiana tabacum and their combination with Silico-sec. In one experiment, 0.4g of each plant material was added to 20 C. maculatus adults (10 couples, aged 1-2 days) in 20g of Ife Brown cowpea seeds, all contained within an air-tight plastic container. Another experiment involved the addition of 0.4g mixtures of Silico-sec and each plant powder (E. aromatica, P. guineense, and N. tabacum) in various ratios (1:5, 5:1, 1:10, 10:1, and 1:1) to the same number of C. maculatus adults in 20g of cowpea seeds, also in separate air-tight plastic containers. All the treatments and their combination were laid out in a completely randomized design (CRD) repeated three times. Data were collected at 12, 24, and 48 at p,0hours post-treatment. Oviposition, adult emergence, and seed weight loss were evaluated. The results demonstrated that both the plant powders and Silico-sec were effective in controlling C. maculatus infestation on cowpea by causing significant adult mortality at p< 0.05, reducing oviposition, suppressing F1 adult emergence, and minimizing seed damage. Among single applications, Silico-sec and E. aromatica powder provided the best protection for stored cowpea, yielding the highest adult mortality, lowest oviposition, most suppressed F1 adult emergence, and minimal seed damage. However, the mixture of Silico-sec and P. guineense at ratios of 5:1 and 10:1 offered the best protection, exhibiting significantly higher mortality, lower oviposition rates, suppressed F1 adult emergence, and reduced seed damage compared to other treatments. This study suggests that combination of P. guineense and Silico-sec is particularly effective in controlling cowpea storage pests and could serve as a viable alternative to synthetic insecticides for protecting stored cowpea against C. maculatus.

Effects of bio-insecticide formulated from M. charantia leaves extract in association with gum Arabic/kaolinite composite on mortality of Callosobruchus maculatus and nutritional composition of cowpea (Vignaunguilata)

The preservation of post-harvest losses of cowpeas constitutes a major challenge for producers worldwide. Therefore, the aim of this work was to investigate the nutritional qualities of cowpea seeds treated with a bio-insecticide formulated from M. charantia leaves extract in association with gum arabic/kaolinite composite. Three bio-insecticides were formulated using different ethyl acetate, hexane and methanol solvents. These bio-insecticides were obtained by introducing each into a bottle, 10 g of composite in 10 mL of a solution (1 mg/L of extract each extract). However, 5 doses of each formulation (1 %–5 %) were prepared. Each dose of insecticide powders received 20 g of cowpea seeds and then infested with 10 C. maculatus previously starved for 48 h. Then, the biochemical parameters of untreated and treated cowpea seeds using the methanol formulation were evaluated. The obtained results showed that insecticide formulated at 5 % with methanol induced 100 % mortality rate on the second day of treatment with a lethal dose of 0.10 % which is related to its high content of triterpenes and polyphenols. The untreated (UWH) and treated (TWH) seeds without husk have the same contents of ash (2.19 %), proteins (29.14 %), fibers (2.69 %), vitamin C (147.32 mg/100 g) and carbohydrates (53.20 %), while untreated and treated seeds with husk showed the same values in these nutrients even for minerals content. Hence, biochemical analyzes of cowpea seeds treated with the formulated insecticide showed no change in nutritional quality and M. charantia leaves extract in association with gum arabic/kaolinite composite could be used as insect repellent.

Effect of fertility levels and stress mitigating chemicals on nutrient content, uptake, intercropping advantage and competition effect in cowpea-baby corn intercropping

The primary goal of this study was to analyze how various row ratios of intercrops, in conjunction with different fertilizer levels with spray of two stress mitigating chemical, affect nutrient content, land productivity, and economic viability during Summer season. Furthermore, we aimed to explore the competitive dynamics within legume/cereal intercropping systems. Hence, A field experiment at Agriculture University, Kota, during the summers of 2019 and 2020, investigated different cowpea + baby corn intercropping system's intercropping indices, nutrient dynamics, uptake, and post-harvest soil nutrient balance under varying recommended fertilizer levels and foliar spray of stress mitigating chemicals. Using a split-split plot design replicated four times, the experiment involved thirty treatment combinations, including five intercropping techniques viz. Sole cowpea, sole baby corn, cowpea + baby corn 2:1, cowpea + baby corn 3:1, cowpea + baby corn 4:1 in the main plot, three fertility levels viz. 100 %, 125 % and 150 % recommended dose of fertilizer (RDF) in subplots, and two stress mitigation chemicals; CaCl2 0.5 % and KNO3 1% in sub-subplots. The findings revealed notable trends, including nitrogen (N) and (P) content in cowpea seeds and straw, baby corn cobs and fodder, as well as enhanced land-equivalent ratio (LER) and monetary advantage index (MAI) within the cowpea + baby corn 2:1 row ratio. However, despite these advantages, total N and P uptake were markedly higher in sole crops. Notably, sole cowpea demonstrated the highest actual N and P balance and lowest was under sole baby corn. Among the fertility levels, the 150 % RDF level exhibited the most favorable outcomes across various parameters, including LER, MAI, NP content, and uptake in both crops. Additionally, higher fertility levels correlated with increased apparent and actual soil nutrient balances. While, among stress mitigation chemicals, CaCl2 0.5 % resulted in significantly heightened N and P uptake. Hence, to optimize intercropping dynamics and maintain soil nutrient balance, it is advisable to intensify cowpea cultivation along with baby corn in a 2:1 row ratio, utilizing 150 % RDF is beneficial. Additionally, alleviating higher temperature stress during the summer season can be achieved by applying a 0.5 % solution CaCl2 through spraying at the flowering and pod development stages of cowpea.

Time of Application of Desiccant Herbicides Affects Photosynthetic Pigments, Physiological Indicators, and the Quality of Cowpea Seeds.

Chemical desiccation is widely used in agriculture to anticipate harvest and mitigate the effects of adverse environmental conditions. It is applied to both grains and seeds. Although this practice is widely used, there are still significant gaps in understanding the effects of different herbicide application times on seed quality and plant physiological responses. The objective of this study was to evaluate the effects of different herbicide application times on cowpea, focusing on seed quality, physiological responses, and biochemical composition, including chlorophylls, carotenoids, sugars, and proline, under nocturnal desiccation. In the first experiment, eight herbicides and two mixtures were applied at night: diquat, flumioxazin, diquat + flumioxazin, glufosinate ammonium, saflufenacil, carfentrazone, diquat + carfentrazone, atrazine, and glyphosate. All of the tested herbicides caused a reduction in normal seedling formation, with the diquat + carfentrazone combination resulting in 100% abnormal seedlings. A significant decrease in chlorophyll levels (chlorophyll a: 63.5%, chlorophyll b: 50.2%) was observed using diquat, which indicates damage to photosynthetic processes, while the carotenoid content increased. Total soluble sugars and proline were also negatively impacted, reflecting physiological stress and metabolic changes in seedlings. In the second experiment, three application times were tested with diquat, diquat + flumioxazin, and diquat + carfentrazone. Nocturnal application showed the most significant reduction in chlorophyll levels and increased carotenoid levels. Application at noon and late afternoon also significantly changed the soluble sugar and proline levels. These results indicate that the herbicide application time directly influences the seeds' physiological quality.

Evaluation of biological traits, morphometric characteristics, feeding preferences, and infestation potential of pulse beetle (Callosobruchus maculatus fab.) on various pulse crops

The pulse beetle, Callosobruchus maculatus (Fab.), is a major invasive pest of stored legume seeds in Pakistan. This study aimed to investigate the biology, morphometrics, feeding potential, and seed damage caused by the beetle on different pulses under laboratory conditions in 2023. The insect laid the highest number of eggs on Vigna unguiculata (8.53±0.95), followed by V. radiata (7.55±0.78), V. mungo (6.66±0.75), Phaseolus vulgaris (6.61±0.63), and Cicer arietinum (5.02±0.37). The mean egg incubation periods were recorded as follows: black gram (5.60±0.54), cowpeas (5.50±0.21), chickpea (4.00±0.72), green gram (4.00±0.37), and kidney bean (0.00±0.00) days, respectively. The egg hatching rates were (39.30%) green gram, (36.10%) cowpeas, (19.50%) chickpea, (5.10%) black gram, and (0.00%) for kidney beans. Notably, while (23.30%) of the eggs were laid on kidney beans, none hatched, and no adults emerged due to the smooth surface of the seed coat. The larvae and pupae development period lasted (24-27) days on black gram, (23-25) days on white gram, (19-21) days on cowpeas, and (18-20) days on green gram. Adult females survived for (14-15) days on cowpeas, (10-15) days on green gram, (12-14) days on black gram, and (10-11) days on chickpea. The mean fecundity was recorded at (6.12±3.17) eggs when two males fertilized one female and (8.73±4.22) eggs when one male fertilized two females. Cowpea seeds were identified as the preferred food source for C. maculatus compared to other pulses. Therefore, effective control of this pest is crucial to protect legume crops.

Interactive Effects of Boron and Molybdenum on Nodulation, Growth and Yield of Cowpea under South Gujarat Condition

Background: Cowpea seeds are nutritious component of human diet and being a legume crop, it also improves the soil fertility by increasing the amount of nitrogen in the soil through symbiotic nitrogen fixation. To study the effect of boron and molybdenum on nodulation, growth and yield of cowpea the field experiment was conducted at the Regional Horticultural Research Station, Navsari Agricultural University, Navsari, Gujarat, India, during summer season of 2019 and 2021. Methods: The experiment was carried out in a factorial randomized block design with 3 replications. Factor-1 consisted of four levels of seed treatments with molybdenum at 2 mg/l (M1), 4 mg/l (M2), 6 mg/l (M3) for 24 hours prior to sowing including control (M0), where as the second factor was consisted of four levels of boron (B) spray at 2 mg/l (B1), 4 mg/l (B2), 6 mg/l (B3) and control at 30 DAS, 45 DAS and 60 DAS with control. Boron was applied in the form of Boric acid and Molybdenum as ammonium molybdate. Result: The treatment combination of seed treatment of molybdenum @ 2 mg/ l with foliar spray of boron @ 4 mg/ l at 30, 45 and 60 DAS (M1B2) has significantly influenced yield parameters and registered maximum number of clusters per plant (6.50), green pod yield per plant (0.153 kg), green pod yield per net plot (3.98 kg), green pod yield per hectare (12.27 tonne). Seed treatment with different levels of molybdenum has significantly influenced nodulation in cowpea and recorded maximum number of nodules per plant (31.69 at final harvest) and fresh nodule weight (0.230 g/plant) in seed treatment of molybdenum @ 2 mg/ l (M2) among all the treatments at final harvest during all the years of study, including pooled analysis.

Toxicity and Synergistic Effect of Native Plants Extracts against the Cowpea Weevil (Callosobruchus maculatus Fab.) (Coleoptera: Bruchidae)

Callosobruchus maculatus causes loss of cowpea seeds and its weight after six months of unprotected storage. This study aimed to evaluate the toxicity and synergistic effects of plant extracts on the biological parameters of C. maculatus from Bobo Dioulasso in order to reduce its damage on cowpea stocks in Bobo Dioulasso city. Seven treatments including an untreated control and doses of three powdery extracts of Cassia nigricans, Zanthoxylum zanthoxyloides and Hyptis suaveolens, and their combinations were compared in a Fischer block with four completely randomized repetitions. One hundred healthy cowpea seeds were mixed with doses of each extract in Petri dishes then submitted as food substrates to ten pairs of C. maculatus for 15 days. The synergistic effect was evaluated following the formula of Chou and Talalay. Extracts of C. nigricans, Z. zanthoxyloides and H. suaveolens was toxic against the weevil. The extract of Z. zanthoxyloides was more toxic to adults (21.16 mg/g) followed by H. suaveolens (51.84 mg/g) and C. nigricans (52.09 mg/g). The infestation rates of batches treated with C. nigricans and Z. zanthoxyloides extracts did not exceed 1.00% compared to 2.00% for H. suaveolens at 20 mg/g. All combinations were synergistic and resulted in 100% mortality and less than 14.98 eggs/female in H. suaveolens coupled with C. nigricans. The application of Z. zanthoxyloides extract alone or the combination of H. suaveolens and C. nigricans extracts would be an alternative for the sustainable management of C. maculatus in cowpea stocks.