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Journal and Journal Articles: Recent submissions
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Interactions between two neotropical phytoseiid predators and consequences for biological control of a shared prey
(2004)The issue of introducing single or multiple natural enemy species for classical biological control has been an area of intense inquiry by ecologists and biological control practitioners. This is particularly relevant to classical biological control of cassava green mite Mononychellus tanajoa (Bondar) (Tetranychidae) in Africa, as this pest mite is shared by several natural enemies in the Neotropics (its area of origin), two of which have been introduced and established widely in Africa. We conducted ... -
Market opportunities for Ugandan banana products: national, regional, and global perspectives
(2004)Banana (Musa spp.) is the most important food crop in Uganda, and it is also the most important income source for the majority of the Ugandan farmers, especially in the Western Ugandan Regions. Besides pests, diseases and declining soil fertility, marketing seems to be a major constraint to production and income generation in the banana sector. To address these problems, the project on Improvement of Banana Marketing and Utilization in Uganda, a joint venture of NARO/NBRP, Makerere University and ... -
A new method for the simultaneous measurement of Ph-dependent cation exchange capacity and ph buffering capacity
(2004)The pH dependent cation exchange capacity (CEC) and pH buffering capacity (pH BC) are two crucial properties in soil fertility management of variable charge soils. However, they are rarely measured, since most of the existing methods are cumbersome and time-consuming. We propose a new method, based on the silver-thiourea (AgTU) method, for the simultaneous measurement of pH dependent CEC and the pH BC. In general, this method consists of first increasing the pH of the soil to about pH 7 and then ... -
Lechec de la production agricole en Afrique francophone
(2004)Cet article examine les changements dans la productivité agricole dans 8 pays francophones. La performance relative du secteur agricole a été évaluée à l'aide de l'analyse de l'enveloppement des données. À partir d'un ensemble de données de panel sur les 8 pays, incluant la période de 30 ans 1970-2000, des méthodes de programmation mathématique ont été utilisées pour mesurer les indices de Malmquist de la productivité totale des facteurs. Il a été constaté que, durant cette période, la productivité ... -
Productivity growth, technical progress, and efficiency change in Africa agriculture
(2004)The paper examines the economic performance of a large number of African countries using an international comparable data set and the latest technique for analysis. The paper focuses on growth in total factor productivity and its decomposition into technical change and efficiency change components. The analysis is undertaken using the data envelopment analysis (DEA). The present study uses data of 16 countries over the period 1970–2001. It was found that, globally, during that period, total factor ... -
Phosphorus fractions in fallow systems of West Africa: effect of residue management
(2004)The effects of burning, incorporation and surface mulching after one year of natural regrowth (NF) and Pueraria cover crop fallows on soil P fractions and maize and cassava yields were assessed. Data were collected between 1998 and 2000 as part of an on-going long-term fallow management trial established in 1989 at the International Institute of Tropical Agriculture (IITA), Ibadan, in the derived savanna zone of southwestern Nigeria. After NF in 1998, burning temporarily increased resin- (63%) and ... -
Diversity and pest control potential of Hymenopteran parasitoids of Ceratitis spp (Diptera, Tephritidae) from mangos in Mali
(2004)In Mali, 1205 mangos (Mangifera indicaL.) were sampled between April and September 2000 andplaced under observation. We recovered 7518 adults of six species of Ceratitis, namely C. cosyra (Walker), C. silvestriiBezzi, C. quinaria (Bezzi), C. fasciventris (Bezzi), C. anonae Graham and C. ditissima (Munro). A total of 436 hymenopteran parasitoids belonging to eight species were recovered from the fruit flies: Psyttalia perproximus(Silvestri), P. cosyrae (Wilkinson), Fopius caudatus (Szépligeti), ... -
Factors affecting adoption of agroforestry practices by farmers in Cameroon
(2005)This paper presents empirical evidence on the impact of socio-economic factors on the adoption of agroforestry practices in Cameroon. The analysis uses primary farm-level data collected from June to December 1996. Three major provinces of the country were covered, namely Centre, Southwest and Northwest Several agroforestry technologies have been promoted among farmers in the zone, including alley farming, improved fallow, live fencing, cut-and-carry fodder and apiculture. The status of adoption ... -
Evaluating the efficiency of entomopathogenic fungi against the Asian longhorned beetle, Anoplophora glabripennis (Coleoptera: Cerambycidae), by using cages in the field
(2004)Three field experiments using cages were conducted in Anhui, China, to test the efficacy of entomopathogenic fungi against adult Asian longhorned beetles, Anoplophora glabripennis (Motschulsky). The use of two commercially available Beauveria spp. strains, Beauveria bassiana (Balsamo) Vuillemin and Beauveria brongniartii (Saccardo) Petch, applied as cultures in fiber bands fastened around tree trunks, was compared with trunk sprays in the first cage experiment. Longevity of A. glabripennis was ... -
Effects of soil temperature, seeding depth and seeding date on rhizoctonia seedling blight and root rot of chickpea
(2004)Effects of soil temperature, seeding depth, and seeding date on rhizoctonia seedling blight and root rot of chickpea. Rhizoctonia solani Kühn, a prevalent fungal pathogen in cultivated prairie soils, can be an important factor affecting seedling establishment of chickpea (Cicer arietinum L.). Studies were undertaken to determine the impact of different soil conditions on seedling establishment, development of root rot, and productivity of desi (Tyson) and kabuli (Sanford) chickpea plants sown in ... -
Efficacy of fiber bands impregnated with Beauveria brongniartii cultures against the Asian longhorned beetle, Anoplophora glabripennis (Coleoptera: Cerambycidae)
(2004)Use of 50 × 500 mm non-woven fiber bands impregnated with cultures of entomopathogenic fungi was investigated for control of Anoplophora glabripennis. Fungal bands produced as a commercial pest control product and obtained from industry contained Beauveria brongniartii NBL 851 while lab-produced bands contained B. brongniartii WU 20 or Metarhizium anisopliae VD 1. In the laboratory, adult longevity decreased when adult A. glabripennis were forced to walk for 5 s on bands impregnated with B. ... -
Effect of temperature on development and survival of the legume pod borer, Maruca vitrata (Fabricius) (Lepidoptera: Pyralidae) reared on a semisynthetic diet
(2004)The effect of temperature on the development and survival of the legume pod borer, Maruca vitrata (Fabricius) (Lepidoptera: Pyralidae) was examined by rearing cohorts on a semi-synthetic diet containing cowpea grain and leaf at different constant temperatures in the laboratory. The developmental periods for eggs, larvae and pupae shortened with increasing temperatures from 14.4°C to 29.3°C. The thermal constants and lower thermal thresholds for the development in the egg, larval and pupal stages ... -
Nutrient concentrations and NH4+‐N mineralization under different soil types and fallow forms in southern Cameroon
(2004)To evaluate the soil‐fertility sustainability of the fallow systems, nutrient concentrations and NH4+‐N mineralization were determined in different soil and fallow types in the humid forest zone of southern Cameroon. Two experiments were conducted, the first comprised planted leguminous tree Calliandra calothyrsus, planted leguminous Pueraria phaseoloides, and regrowth mainly composed of Chromolaena odorata on the Typic Kandiudult. The second experiment made up of a fallow dominated by C. odorata, ... -
Effect of hostplant resistance on growth and developmental parameters of the flower bud thrips, Megalurothrips sjostedti (Trybom) on some resistant cowpea (Vigna unguiculata [L.] Walp.) cultivars
(2004)The effect of host plant resistance on growth and developmental parameters of the bean flower thrips Megalurothrips sjostedti Trybom was determined on nine cowpea (Vigna unguiculata {L.}Walp.) cultivars under laboratory conditions. Newly emerged adults M. sjostedti were confined on peduncles with floral buds of the different cowpea cultivars. M. sjostedti suffered 100% pre-imaginal mortality on cowpea lines Moussa local, TVu1509, TVx3236, Sewe and Sanzibanili. Antibiosis is believed to be the ... -
Evaluation of seed treatment chemicals for the control of seedling bacterial blight of cowpea in Northern Nigeria
(2004)The effect of metalaxyl + mancozeb (RidomilMz), metalaxyl + carboxin + furathiocarb (Apron plus), metalaxyl + copper-1-oxide (Ridomil plus), benomyl (Benlate), maneb + thiophanate-methyl (Labilite) and zinc + maneb (Mycotrin) on seed germination, incidence and severity of seedling bacterial blight in cowpea induced by Xanthomonas campestris pv vignicola was assessed on the field in the 2000 and 2001 cropping seasons. Zinc + maneb gave the best control and was closely followed by metalaxyl + carb ... -
The influence of mineral fertilizer application and plant nutrition on plantparasitic nematodes in upland and lowland rice in Cote dIvoire and its implications in longterm experiments
(2004)Mineral fertilizer application and consequent plant nutrition has long been observed to influence associated plant-parasitic nematode population densities, offering the potential as a nematode management option. Observations were made on the influence of mineral fertilizer application on nematode populations on three separate long-term rice experiments, (differential mineral application on upland and on lowland rice, and P application on upland rice) undertaken between 1994 and 1997 in Côte d'Ivoire. ... -
Incorporating shortseason legumes and green manure crops into maizebased systems in the moist Guinea savanna of West Africa
(2004)A three-year trial was conducted on a degraded soil in the moist Guinea savanna of northern Nigeria to assess the possibility of improving productivity and economic viability of maize-based systems by incorporating short-season legumes and green manure crops into the cropping pattern. Treatments included double cropping legume-maize systems, full-season sole maize receiving various amounts of nitrogen, green manure crop mucuna (Mucuna pruriens var. utilis) followed by sole maize and a legume-maize ... -
How issues get framed and reframed when different communities meet: a multilevel analysis of a collaborative soil conservation initiative in the Ecuadorian Andes
(2004)Drawing on qualitative data from a longitudinal case study of a collaborative soil conservation initiative in southern Ecuador, we study how multiple actors, including university experts, development organizations and local communities, make sense of the issues from different perspectives through the process of issue framing. Starting from an analysis of the actors' usual issue frames, we point out their differences in selecting aspects, connecting them and drawing boundaries around the issues. ... -
Effect of temperature on the survival and infectivity of Pseudotheraptus devastans vector
(2004)The aim of this study was to investigate under a controlled environment, the effect of temperature on the survival and infectivity of Pseudotheraptus devastans Distant, a cassava anthracnose disease vector. The insect P. devastans was collected from young cassava (Manihot esculenta Crantz) field plots, at the International Institute of Tropical Agriculture, (IITA), Ibadan, Nigeria. A mixture of the different developmental stages of eggs, first to fifth instar nymphs, and adults, were incubated in ... -
Inheritance of purple pigmentation on vegetative parts in cowpea (Vigna unguiculata (L.) Walp.)
(2004)Two cowpea varieties Kanannado and IAR-1696 both of which are purple pigmented on the nodal region of their main stem, base of tertiary branches, base of the stalk of the trifoliate and base of peduncle were crossed to two other varieties, IT93K-693-2 and IT87D-941-1. These two varieties are completely devoid of any pigmentation on the plant parts mentioned above. The F1, F2 and backcross populations together with the parentals were planted in the screenhouse and evaluated for pigmentation. Results ...
