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Management of insects pests in storage for preservation of Cucumeropsis mannii seeds  [cached]
A.A. ADEKUNLE and NGWANMA U. UMA
Indian Phytopathology , 2012,
Abstract: The preservation of Cucumeropsis mannii Naud-Holl (‘Egusi’ melon) seeds by manipulating the temperature, relative humidity and type of storage was carried out. Fungi were pathogenic on melon seeds stored at high relative humidities of 100% and 91%, but not at lower humidity between 0 and 55%. Disease manifested on the melon seeds at temperature of 20°C and 37°C whereas no disease incidence was observed at temperatures 5-10°C and 40°C. Disease incidence varied with storage condition. Seeds stored in the oven (40°C±2; R.H. 0%) had no fungal isolate after 12 months storage. Those seeds stored in the garden (27-33°C; R.H. 76-90%) and laboratory shelf (28°C-30°C; R.H. 80-87%) for the same period had fungal isolates which were absent in the beginning of storage. There was an increase in the percentage infectivity of the melon seeds as the storage period increased, for seeds stored in the garden and laboratory. Seeds stored in the oven were not infected at the end of 12 months storage period. Unshelled melon seeds were less infected with fungi when compared to shelled seeds.
Triacylglycerols and fatty acids composition of egusi seed oil (Cucumeropsis Mannii Naudin)
Kapseu, C.,Kamga, R.,Tchatchueng, J. B.
Grasas y Aceites , 1993,
Abstract: Triacylglycerols were determined from a Cameroonian (African) white egusi seed oil (Cucumeropsis Mannii Naudin) using reversed phase high performance liquid chromatography. The fatty acid composition of two types of seed (red and white) is obtained by capillary gas chromatography. The study of the triacyiglycerol composition obtained in white egusi seed oil revealed that only nine triacylglycerols were present in amounts above 1% (area). The first five triglycerides represent more than 80% of the total triacylglycerols, and the major triacyiglycerol was palmitoyldilinoleoylglycerol, accounting for 23.6% of the oil. This oil contains a high proportion of linoleic acid (60% wt/wt). Se determinó la composición en triacilgliceroles del aceite de semilla de egusi del Camerún (Cucumeropsis Mannii Naudin) utilizando cromatografía líquida de alta eficacia en fase inversa. La composición en ácidos grasos de dos tipos de semillas de egusi (roja y blanca) fue obtenida por cromatografía de gases en columna capilar. El estudio de la composición en triacilgliceroles del aceite obtenido de semilla blanca de egusi reveló que sólo nueve de ellos se encontraban en proporción superior al 1% (en área). Cinco triacilgliceroles representaron más del 80% del total y el mayoritario fue el palmitoildilinoleoilglicerol (23,6%). Este aceite contiene una alta proporción de ácido linoleico (60%).
Cytology and Molecular Cytogenetics of Cucumeropsis mannii Naudin: Implications for Breeding and Germplasm Characterization  [PDF]
Julian O. Osuji,Bosa E. Okoli,J.S. Pat Heslop-Harrison
International Journal of Botany , 2006,
Abstract: Cytological and molecular cytogenetic studies were conducted on the two accessions of Cucumeropsis mannii Naudin to establish the true somatic chromosome count, investigate the occurrence and number of ribosomal RNA genes in its genome as well as investigate any cytological and cytogenetic variation in the two cultivars of the monospecific taxon. Chromosomal counts from squashed root tips stained with FLP orcein and DAPI stained mitotic chromosomes showed a somatic count 2n = 24 for this species. The chromosomes were small in size measuring 3-4.5 μm long and mostly varied from submetacentric to subacrocentric in shape. Both 18S-5.8S-25S and 5S rRNA genes were observed in the genome. Four sites, comprising two major and two minor, of 18S-5.8S-25S rRNA genes were present on four of the largest chromosomes (4.5 μm long) while two sites of the 5S rRNA genes were observed on two other individuals of the largest chromosomes. This report establishes the correct somatic chromosome count as well as the ribosomal rRNA features of this taxon. It also shows no cytological variation between the two cultivars of this species.
Effectiveness and efficiency of chemical mutagens in cowpea (Vigna unguiculata (L.) Walp)
D Dhanavel, P Pavadai, L Mullainathan, D Mohana, G Raju, M Girija, C Thilagavathi
African Journal of Biotechnology , 2008,
Abstract: A study was undertaken in a cowpea (Vigna unguiculata (L.) Walp.) variety CO 6 to assess the efficiency and effectiveness of chemical mutagens; ethyl methane sulphonate (EMS), diethyl sulphate (DES) and sodium azide (SA). EMS treatments were found highly effective than the other chemicals. Mutagenic effectiveness and efficiency decreased with increase in all mutagenic treatments.
Importance and practices of Egusi crops (Citrullus lanatus (Thunb.) Matsum. & Nakai, Cucumeropsis mannii Naudin and Lagenaria siceraria (Molina) Standl. cv. 'Aklamkpa') in sociolinguistic areas in Benin  [PDF]
Achigan-Dako E.G.,Fagbemissi R.,Avohou H.T.,Vodouhe R.S.
Biotechnologie, Agronomie, Société et Environnement , 2008,
Abstract: Importance et culture de Egusi (Citrullus lanatus (Thunb.) Matsum. & Nakai, Cucumeropsis mannii Naudin et Lagenaria siceraria (Molina) Standl. cv ' Aklamkpa ') dans les régions sociolinguistiques du Bénin. Les légumes traditionnels africains sont considérés comme potentiellement utiles pour contribuer à la sécurité alimentaire et à la génération de revenu au niveau des communautés locales. Cependant, Egusi (Citrullus lanatus subsp. mucosospermus, Cucumeropsis mannii et Lagenaria siceraria cv. ' Aklamkpa ') a rarement fait l'objet de recherche et de promotion alors que sa culture persiste dans les systèmes de production de plusieurs pays de l'Afrique de l'Ouest. Cette étude met l'accent sur le r le social des cultures de Egusi et leur importance dans le système de production des groupes sociolinguistiques au Bénin. En 2005, une investigation des systèmes de production et de culture de cinq régions socioculturelles prédominantes indique que la culture de Egusi est classée parmi les dix premières spéculations, selon la perception des ménages interrogés. Le rang attribué aux cultures de Egusi est relatif au genre mais pas à l'age. Les agriculteurs allouent en moyenne 0,74 ha pour la production de Egusi, avec une différence significative d'une région sociolinguistique à une autre. Dans la communauté Mahi-Fon du centre Bénin, par exemple, nous avons observé des champs de production de Egusi allant jusqu'à 5 ha. L'espèce la plus cultivée est C. lanatus subsp. mucosospermus. Cependant, dans la communauté Adja du sud Bénin, la préférence des agriculteurs est pour L. siceraria cv. ' Aklamkpa '. Egusi se cultive au champ et en jardin de case, soit en association ou en monoculture. C. mannii est généralement cultivée en association et joue un r le social très important dans les communautés Nagot-Yoruba. Bien que Egusi ne soit pas une culture réservée aux femmes, ces dernières réalisent la plupart des activités post-récolte. Les utilisations associées à la culture de Egusi varient d'un groupe sociolinguistique à un autre et constituent une base essentielle de promotion de la culture.
Plants regeneration from African cowpea variety (Vigna unguiculata L. Walp.)
MS Diallo, A Ndiaye, M Sagna, YK Gassama-Dia
African Journal of Biotechnology , 2008,
Abstract: Vigna unguiculata (L.) Walp. plant was efficiently regenerated from cotyledonary node explants. The shoots multiplication rate was influenced by the presence or the absence of cotyledons. Explants with two entire cotyledons from 5-6-d-old seedling produced the greater number of shoots (8.30) after two weeks on B5 medium supplemented with 1 mg.l-1 BAP. Shoots elongation is optimal on media supplemented with kinetin. Rooting is improved after an induction phase on half strength MS, producing 95.83% of rooted plants. No confined atmosphere surrounding plantlets is essential for survival during acclimatization. The regenerated plants flowered and produced pods and viable seeds.
Floral Biology and Pollination Ecology of Cowpea (Vigna Unguiculata L. Walp)  [cached]
Ige, O. E.,Olotuah, O.F,Akerele, V.
Modern Applied Science , 2011, DOI: 10.5539/mas.v5n4p74
Abstract: Studies on the floral biology and pollination ecology of three varieties of cowpea (Vigna unguiculata L. Walp) were carried out. The varieties studied were Var. Oloyin, Var. Sokoto, and Var. Drum. Cowpea is a self pollinated crop which is encouraged by the arrangements of the floral parts. However, Insects visiting cowpea flowers have been implicated in the movement of pollen from one cowpea plant to another. Flower opening of cowpea begins between 6:00am and 6:30am and closes between 11:30am and 12:00pm. Pollen analysis showed similarities in the pollen morphology of the cowpea varieties. Moreover Var. Drum produced the highest number of pollen grains per flower in terms of pollen productivity.
Caractérisation botanique et agronomique de trois espèces de cucurbites consommées en sauce en Afrique de l'Ouest : Citrullus sp., Cucumeropsis mannii Naudin et Lagenaria siceraria (Molina) Standl  [PDF]
Zoro Bi I.A.,Koffi K.K.,Djè Y.
Biotechnologie, Agronomie, Société et Environnement , 2003,
Abstract: Botanical and agronomical characterisation of three species of cucurbit consumed as sauce in West Africa: Citrullus sp., Cucumeropsis mannii Naudin and Lagenaria siceraria (Molina) Standl. There are in C te d'Ivoire at least five species of cucurbit incorrectly called ""pistaches"" in town and cultivated at small scale by women for their oleaginous seeds that are a great importance in the sociocultural live of several peoples. Nevertheless, few studies aimed at the improvement of these plants (related notably to taxonomy, genetic resources collecting missions, genetic characterisation, agronomic evaluation, and selection) have been carried out. In order to set up a list of reliable traits that should be examined easily during and after collecting missions, we carry out in the present study, for three species (Citrullus sp., Cucumeropsis mannii Naudin and Lagenaria siceraria (Molina) Standl) a botanic description and an analysis of eleven agronomic traits: 100-seeds weight, germination rate, seedlings emergence time, matured fruit weight, matured fruit decomposition time, mean number of seeds per fruit, seeds shape, fruit diameter, fruit interior cavity diameter, flowering time, and fruiting time. Statistical analyses using nine of these traits showed that the three species can be completely distinguished with six traits whereas the three other traits allowed partial distinction. Low yields have been observed for the three species: 11.41 kg/ha of decorticated seeds for C. mannii, 18.51 kg/ha for Citrullus sp. and 75.14 kg/ha for L. siceraria. From the observed yield components, the possibilities to improve the production of these cucurbits are discussed.
Response of Cowpea (Vigna unguiculata L. Walp.) to Water Stress and Phosphorus Fertilization
V.G. Uarrota
Journal of Agronomy , 2010,
Abstract: This study was conducted in the experimental college of agriculture and forestry, in Maputo-Mozambique, in order to evaluate the response of cowpea (Vigna unguiculata L. Walp.) to irrigation and phosphorus and test the hypothesis that high levels of phosphorus improves the tolerance of plants to water stress. We used a variety IT 18 of cowpea, short cycle and ended. The experiment was subdivided into building plots complete block design with five repetitions, the irrigation factor was fixed at the main plot with two levels (with irrigation and without irrigation) and phosphorus factor in sub-plots with 3 levels (0, 20 and 40 kg ha-1 of phosphorus). The fertilization strongly influenced the yield and the number of pods per plant in both irrigation conditions. The effect of fertilizing phosphorus was higher under irrigation. The interaction was significant only for grain yield and number of pods, which means that the effect of phosphorus in these two variables has not been the same for the two levels of irrigation, high levels of phosphate fertilizer (P2O5) have improved the tolerance of cowpea when not irrigated.
Physiological and biochemical responses of cowpea (Vigna unguiculata (L.) Walp) to ozone
Chanin Umponstira,Warin Pimpa,Suckaluck Nanegrungsun
Songklanakarin Journal of Science and Technology , 2006,
Abstract: The aim of this research was to investigate physiological and biochemical responses of cowpea (Vigna unguiculata (L.) Walp) to ozone. There were two main factors of the experiment; level of ozone concentration at 40 and 70 ppb and plant ages at 7 and 21 days. Plants were grown in fumigation chambers in which inlet air was filtered by a charcoal filter. Additional ozone was given 8 hours/day for 7 days in ozone fumigating chambers. The ozone concentration in the control chambers was less than 10 ppb. The results showed the biomass of ozone-fumigated plants was significantly lower and leaf injury of ozone fumigated plants was significantly greater compared to the control group. The major visible-injury symptom appeared as chlorosis on the upper surface of the leaves. Antioxidant levels in the charcoal filtered (CF) plants and ozoned plants had significant differences because of their detoxification role in removing ozone and its derivatives. The ozone treatment of 7-day-old plants showed superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) levels significantly higher than in 21-day-old plants and total ascorbate concentrations significantly lower than 21-day-old plants. These results showed that different ozone concentrations exhibit different effects on antioxidant production. Analysis of antioxidants daily for 7 days found that antioxidant levels rapidly changed. Notably, SOD and total ascorbate could be selected as indicators for ozone-effect monitoring in plants. This indicates that cowpea is sensitive to ozone and may be usable as an ozone bioindicator. In conclusion, plant age, ozone concentration and the duration to exposure to ozone were the main physiological or biochemical responses of cowpea. An efficient defense system was generated from a combination of antioxidants.
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