26 research outputs found
Sustainable use and conservation of Vitex doniana Sweet: unlocking the propagation ability using stem cuttings
One of the major constraints for domesticating widely used wild tree resources by local communities is the lack of adequate propagation techniques. In the case of Vitex doniana, seed propagation has usually been reported difficult and vegetative regeneration is rarely explored. To understand how stem cutting size or hormone application affect the regeneration and early growth ability in that species we used two categories of cutting diameter (1cmVitex doniana to reduce the pressure on wild tree population in Benin
Efficacy of mosquito netting for sustainable small holders' cabbage production in Africa
The efficacy of a mosquito netting to protect cabbages, Brassica oleracea L., against pests was investigated in field trials in Benin, West Africa. A polyester net covered the plants at night by using a wood armature. The net was removed during the day to prevent overheating and excessive shade, both problems of insect-proof screens used under tropical conditions. The number of all lepidopteran larvae with netting protection and foliar insecticide sprays was significantly lower than the unprotected control. The number of diamondback moth, Plutella xylostella (L.), was significantly lower with netting protection compared with foliar insecticide sprays and control. Netting treated with deltamethrin gave total protection of young plants against the aphid Lipaphis erysimi (Kaltenbach). At harvest, the number of marketable cabbages protected with untreated netting was significantly higher compared with the production with foliar insecticide sprays. The protection of cabbages with netting can be an economically viable method. Considering the price of cabbages on local markets (US247 by using netting, US117 for controls. The net returns for using netting are based on replacing the netting each crop cycle. But netting can be reused several times, depending upon conditions, increasing the profit margin. The netting protection may be an alternative to the growing unsustainable practices of vegetable cropping in peri-urban areas of tropical countries
Performance of Varieties of Gboma (Solanum Macrocarpon) under Disease Pressure with Organic Amendment in Southern Benin
‘Gboma’, the African eggplant, is one of the traditional vegetables in Benin that has not been studied in terms of varietal differences and reaction to diseases. Colletotrichum stem rot of Solanum macrocarpon ‘Gboma’ is a widespread disease in S. macrocarpon cultivated areas of South Benin. This study is focused on the disease diversity on S. macrocarpon and determines the behaviour of the varieties of S. macrocarpon to diseases using different doses of organic fertiliser. The appearance of disease symptoms was investigated in two locations (Cotonou and Sèmè) on six S. macrocarpon varieties fertilised with 20 t ha-1 and 40 t ha-1 of chicken manure in a completely randomised block design with 4 replications. The stem rot of S. macrocarpon caused by the fungus Colletotrichum capsici was the only recorded disease. The incidence of the disease was measured as area under the incidence progress curve. The disease incidence was significantly higher in Somalie Gboma variety and significantly lower in the Abidjan Gboma variety at both locations. Regarding the effect of amended manure, the disease incidence was low in plots amended with 40 t ha-1 and high in those amended with 20 t ha-1, with significant differences (p = 0.0237) obtained in the Cotonou location. This is in Benin the first record of C. capsici as pathogen of S. macrocarpon with positive Koch postulate reaction and of the Abidjan Gboma as resistant variety of S. macrocarpon to C. capsici. For this disease reduction and yield increase, organic amendment of 40 t ha-1 chicken manure is recommended.Keywords : Traditional vegetable, Disease diversity, African eggplant, Solanum macrocarpon, Indigenous vegetable, Benin.‘Gboman’, la grande morelle (Solanum macrocarpon), est l’un des légumes feuilles traditionnels du Bénin qui n’ont pas fait l’objet d’une étude de comportement variétale aux maladies. La pourriture de tige de S. macrocarpon provoquée par Colletotrichum est répandue dans les zones de culture au sud du Bénin. Cet article met en exergue la diversité des maladies inféodées à S. macrocarpon et étudie le comportement variétal de ce légume face aux maladies avec l’utilisation de doses variables de fertilisant organique. Les symptômes des maladies ont été évalués dans deux localités (Cotonou et Sèmè) sur six variétés de S. macrocarpon fertilisées avec 20 t ha-1 et 40 t ha-1 dans un dispositif de bloc aléatoire complet à quatre répétitions. La pourriture de tige de S. macrocarpon causée par le champignon Colletotrichum capsici a été la seule maladie observée. L’incidence de la maladie a été mesurée comme l’aire sous la courbe de progression de l’incidence de la maladie. Elle a été significativement élevée chez la variété Somalie Gboma et significativement faible chez la variété Abidjan Gboma dans les deux localités. En ce qui concerne l’effet de la matière organique apportée aux plants de S. macrocarpon, l’incidence de la maladie a été faible sur les parcelles amendées avec 40 t de fiente à l’hectare et élevée sur les parcelles amendées avec 20 t de fiente à l’hectare avec une différence significative dans la localité de Cotonou (p = 0,0237). Ce travail rapporte pour la première fois, l’infestation de S. macrocarpon par C. capsici et la variété Abidjan Gboma comme résistante à C. capsici. Pour réduire cette maladie et augmenter le rendement, un amendement organique de 40 t ha-1 de fiente de volaille est recommandé.Mots clés : Légumes traditionnels, Solanum macrocarpon, diversité de maladies, Colletotrichum capsici, Béni
Plantes pesticides et protection des cultures maraichères en Afrique de l'Ouest (synthèse bibliographique)
Pesticidal plants and vegetable crop protection in West Africa. A review. Introduction. Vegetable crops play a leading role in human nutrition and contribute significantly to the incomes of families in West Africa. However, their production is hampered by pressure from pests, which limits their productivity. Literature. This review, based on scientific publications, aims to evaluate the potential of pesticidal plants as an alternative to the use of synthetic pesticides to control vegetable crop pests in West Africa. It shows that the primary current method used to control these pests is mainly based on synthetic pesticides. However, in view of their harmful effects on humans and the environment, in addition to the range of resistant pest populations, the search for alternative approaches is needed. Pesticidal plants are a promising alternative in the West African context. Indeed, various species of pesticidal plant can be used as plant extracts or in association with other crops in pest management. These plants are presented in this review article. Conclusions. Pesticidal plants can be a promising alternative for the pest management of vegetable crops. However, most of these pesticidal plants are uncultivated. Exploring the biocidal capacities of these interesting plants, such as the genus Ocimum, known for its therapeutic, medicinal and food uses, could be of interest for farmers. However, populations need to be made informed of the long-term benefits of products treated with pesticidal plant extract, in order to facilitate their use
Performance of varieties of Gboma (Solanum macrocarpon) under disease pressure with organic amendment in Southern Benin
‘Gboma’, the African eggplant, is one of the traditional vegetables in Benin that has not been studied in terms of varietal differences and reaction to diseases. Colletotrichum stem rot of Solanum macrocarpon ‘Gboma’ is a widespread disease in S. macrocarpon cultivated areas of South Benin. This study is focused on the disease diversity on S. macrocarpon and determines the behaviour of the varieties of S. macrocarpon to diseases using different doses of organic fertiliser. The appearance of disease symptoms was investigated in two locations (Cotonou and Sèmè) on six S. macrocarpon varieties fertilised with 20 t ha-1 and 40 t ha-1 of chicken manure in a completely randomised block design with 4 replications. The stem rot of S. macrocarpon caused by the fungus Colletotrichum capsici was the only recorded disease. The incidence of the disease was measured as area under the incidence progress curve. The disease incidence was significantly higher in Somalie Gboma variety and significantly lower in the Abidjan Gboma variety at both locations. Regarding the effect of amended manure, the disease incidence was low in plots amended with 40 t ha-1 and high in those amended with 20 t ha-1, with significant differences (p = 0.0237) obtained in the Cotonou location. This is in Benin the first record of C. capsici as pathogen of S. macrocarpon with positive Koch postulate reaction and of the Abidjan Gboma as resistant variety of S. macrocarpon to C. capsici. For this disease reduction and yield increase, organic amendment of 40 t ha-1 chicken manure is recommended
Susceptibility of ten tomato cultivars to attack by Tetranychus evansi Baker & Pritchard (Acari: Tetranychidae) under laboratory conditions
Published online: 28 Jul 2020We evaluated, in a laboratory experiment, the susceptibility of 10 tomato cultivars to the attack by the tomato red spider mite Tetranychus evansi, an invasive pest of this crop in Benin. Among the 10 cultivars tested, six were imported (i.e. Roma VF, Tima, Rio Grande, Buffalo, Petomech, and TLCV15) and four local (i.e. Akikon, Tounvi, TomL4, and Kèkèfo). Leaf disks (2.5 cm diameter) excised from leaves of tested cultivars, and placed upper side down on top of water-soaked cotton wool laying in 9.5 cm diameter Petri dishes (6 leaf disks per Petri dish), served both as experimental units and feeding source for the mites. Mites were individually placed on leaf disks of each cultivar and several biological parameters – development, reproductive parameters and longevity – were assessed. The experiments were performed at 27 ± 1 °C, 65–70% RH, and 12:12 h (L: D) photoperiod. Our results revealed significant effects of tomato cultivars on several biological parameters of T. evansi, especially the developmental time of the egg stage (P ˂ 0.0001), and the larval stage (P = 0.0113), as well as female oviposition period (P = 0.0002). Likewise, female longevity (P = 0.0095) and fecundity (i.e. egg/♀, P = 0.0055) were significantly affected. The sex-ratio of the progeny was generally similar for all the cultivars except for Buffalo and Tounvi on which most juveniles did not develop beyond the larval stage. These two cultivars appeared as potential tomato cultivars for implementation of IPM strategies for the control of T. evansi