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Journal and Journal Articles: Recent submissions
Now showing items 1541-1560 of 5273
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Comparative effects of explant source and genotype on in vitro tuberization in Dioscorea alata and D. rotundata
(2004)Single node cuttings of two genotypes each of Dioscorea alata and D. rotundata from both plants grown in screen houses and in vitro plantlets were cultured in a tuberization medium. The screen house explants had significantly higher plantlet tuberization and primary nodal complex formation, and more tubers and primary nodal complexes per plantlet than in vitro explants, whereas in vitro explants performed better only in nodes per plantlet. It appears that in vitro tuberization is explant‐, species‐ ... -
Sclerotinia stem rot caused by Sclerotinia Sclerotiorum on soybeans in Nigeria
(1992)In Aug. 1990, S. sclerotiorum was isolated from soyabean cultivars TGx 1440-1E and TGx 1627-3F at Bukuru, Plateau, Nigeria. Disease symptoms are described. This is the first report of Sclerotinia stem rot of soyabean in Nigeria and West Africa. -
Merging biotechnology with biological control: banana Musa tissue culture plants enhanced by endophytic fungi
(2004)Among the major constriats to highland cooking banana (Musa spp. AAA-EA) production in Uganda is the high pests infestation levels. Most important are the banana weevil cosmopolites sordidus and a complex of plant parasitic root nematodes of which Radopholus similis is the most important. Clean planting material, such as tissue culture derived plants, is now being promoted in Uganda for establishments for new fields, although pest re-infestation remains a vital concern. Fungal endophytes are ... -
Outbreak of red leaf blotch caused by Dactuliochaeta glycines, on soybeans in Nigeria
(1992)Red leaf blotch, caused by Dactuliochaeta glycines (R.B. Stewart) Hartman & Sinclair (2) (= Pyrenochaeta glycines R.B. Stewart), was observed on soybeans (Glycine max (L.) Merr.) at Bukuru, near Jos in the state of Plateau, Nigeria, in 1990. Over 80% of the plants in the 4¬ha nonirrigated, sandy loam field nursery showed symptoms. Dark red to brown lesions on primary leaf veins eventually enlarged and coalesced to form irregular blotches 5¬10 mm in diameter. Most blotches had ash¬gray centers with ... -
Macrophomina phaseolina on the tropical cover crops Mucuna pruriens var. utilis
(1992)During the rainy season of 1991, severely reduced plant stands and severely stunted plants were observed in several fields of the cover crop Mucuna pruriens (L.) DC. var. utilis (Wallich ex Wight) Baker ex Burck at the International Institute of Tropical Agriculture in Ibadan, Nigeria. Initial outbreak of symptoms followed a brief dry period, and subsequently more than 75% of the crop was lost. When the sites were replanted, the mucuna was again severely affected, although there was no dry period. ... -
Spatial distribution of Rastrococcus invadens Williams (Hom., Pseudococcidae) in mango trees
(1992)The spatial dispersion pattern and the intracanopy distribution of the mango mealybug, Rastrococcus invadens Williams, were assessed during one year in a small mango plantation, in order to develop sampling plans and facilitate sampling in mango trees. Mean number of mango mealybugs per leaf differed significantly between trees for most sampling dates, between old and young leaves, and between geographical quadrants. A second one‐time assessment of the intracanopy distribution of the mango mealybugs ... -
Some studies on cowpea aphidborne mosaic and pea seedborne mosaic potyviruses in Nepal
(1996)Various virus‐like symptoms were recorded on field‐grown cowpea(Vigna unguiculataL. Walp) and pea(Pisum sativumL.) during 1989–1990 at the experimental farm of the Institute of Agriculture and Animal Sciences (IAAS), Rampur, Chitwan valley, in the central terai plains of Nepal. The causal agent(s) causing narrow and/or curled leaves, and stunting of pea, and prominent mosaic and vein banding of cowpea were transmitted by both aphids and sap inoculations. Electron microscopic examination of leaf ... -
Development in cowpea (Vigna unguiculata); l: the influence of temperature on seed germination and emergence
(1996)The base (Tb), optimum (To) and ceiling (Tce) temperature for 50% seed germination and seedling emergence, and the thermal time at sub-optimal temperatures (θ1), were examined in experiments with a range of cowpea genotypes from different habitats and latitudes. There was substantial genotypic variation in seed germination for Tb and To, but not for Tce. There was no evidence that genotypes from semi-arid habitats had higher values of To or Tce, but estimates of Tb for seed germination were related ... -
Retroconversion exercise in an online thesaurus environment: a post cardcatalogue conversion experience at the International Institute of Tropical Agriculture in Ibadan
(1996)Faced with the need to undertake the retrospective conversion of the library catalogue, we searched the literature for advice and experiences which might prove useful for our situation. However, apart from Crowe and Matthews reporting on OCLC and Dartmouth respectively, there seemed to be little of value to us.
