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1. Agronomic Potential of Eleven Phosphate Rocks from Brazil, Colombia, Perú, and Venezuela

Author:
L. A. Léon; W. E. Fenster; L. L. Hammond
Source:
Soil Science Society of America journal 1986 v.50 no.3 pp. 798-802
ISSN:
0361-5995
Subject:
Haplustox; Megathyrsus maximus; ammonium; citrates; citric acid; formic acid; greenhouse experimentation; laboratory techniques; pH; rocks; solubility; triple superphosphate; Brazil; Colombia; Florida; Israel; North Carolina; Peru; Tennessee; Tunisia; Venezuela
Abstract:
... The agronomic potential of 11 South American phosphate rocks was estimated by four laboratory methods (neutral ammonium citrate with two extractions, acid ammonium citrate [pH 3], 2% citric acid, and 2% formic acid) and by crop response data obtained from a greenhouse experiment with guinea grass (Panicum maximum Jacq.) on an acid (pH 4.9) Tropeptic Haplustox (Las Gaviotas) from Colombia. Standard ...
DOI:
10.2136/sssaj1986.03615995005000030046x

2. The effect of soil properties and level of fertilizer application on the dissolution of Sechura rock phosphate in some soils from Brazil, Colombia, Australia and Nigeria

Author:
Hughes, J.C.; Gilkes, R.J.
Source:
Soil research 1986 v.24 no.2 pp. 219-227
ISSN:
0004-9573
Subject:
fertilizer application; soil properties; soil chemistry; physicochemical properties; rock phosphate; Nigeria; Australia; Brazil; Colombia
DOI:
10.1071/SR9860219

3. Topically applied ivermectin: efficacy against torsalo (Diptera: Cuterebridae)

Author:
Uribe, L.F.; McMullin, P.F.; Cramer, L.G.; Amaral, N.K.
Source:
Journal of economic entomology 1989 v.82 no.3 pp. 847-849
ISSN:
0022-0493
Subject:
cattle; infection; Dermatobia hominis; insect control; ivermectin; Brazil; Colombia
Abstract:
... To determine the systemic efficacy and persistence of a 0.5% ivermectin topical formulation against natural infestation of torsalo, Dermatobia hominis (L., Jr.), larvae in cattle, two trials in Colombia and two trials in Brazil were done. Of 56 infested cattle used in these trials, 28 were treated and 28 served as untreated controls. The formulation was poured along the back of each animal at a ra ...
DOI:
10.1093/jee/82.3.847
PubMed:
2754099

4. The genus Melocactus (Cactaceae) in Central and South America

Author:
Nigel P. Taylor
Source:
Bradleya 1991 v.9 pp. 1-80
ISSN:
0265-086X
Subject:
Melocactus conoideus; Melocactus curvispinus; Melocactus deinacanthus; Melocactus glaucescens; Melocactus paucispinus; Melocactus violaceus; cacti and succulents; color; fruits; nomen novum; seed morphology; surveys; Andes region; Brazil; Caribbean; Central America; Colombia; Cuba; Mexico; Venezuela
Abstract:
... Melocactus Link & Otto (31 spp.) is revised in Central and South America to include 24 species and 10 heterotypic subspecies, arranged in 6 species-groups primarily on the basis of fruit, seed and spination characters: M. oreas Group incl. M. oreas (2 subspp.), M. ernestii (2 subspp.), M. bahiensis (2 subspp.), M. conoideus; M. deinacanthus Group (1 sp.); M. levitestatus Group (1 sp.); M. azureus ...
DOI:
10.25223/brad.n9.1991.a1

5. Oviposition attractants and stimulants for the sandfly Lutzomyia longipalpis (Diptera: Psychodidae)

Author:
Elnaiem, D.E.A.; Ward, R.D.
Source:
Journal of medical entomology 1992 v.29 no.1 pp. 5-12
ISSN:
0022-2585
Subject:
Lutzomyia longipalpis; larvae; culture media; oviposition; attractants; mortality; Brazil; Colombia
Abstract:
... Oviposition preferences of Lutzomyia longipalpis Lutz & Neiva for surfaces containing frass (colony remains), larval rearing medium, and rabbit feces were investigated in the laboratory. In oviposition choice chambers, significantly more eggs were laid on sites containing frass, larval rearing medium, or rabbit feces than on untreated control sites. Experiments using unwashed and washed materials ...
DOI:
10.1093/jmedent/29.1.5
PubMed:
1552528

6. A Dynamic Model of Oligopoly in the Coffee Export Market

Author:
Larry S. Karp; Jeffrey M. Perloff
Source:
American journal of agricultural economics 1993 v.75 no.2 pp. 448-457
ISSN:
0002-9092
Subject:
Bayesian theory; agricultural economics; coffee beans; dynamic models; exports; markets; oligopoly; Brazil; Colombia
Abstract:
... A linear‐quadratic, dynamic feedback oligopoly model that nests various market structures is used to estimate the degree of competitiveness and the adjustment paths of the two largest coffee exporters, Brazil and Colombia. Their estimated behavior is relatively competitive. This subgame perfect dynamic model is compared to a standard static oligopoly model and the open‐loop model (the dynamic gene ...
DOI:
10.2307/1242929

7. Mitochondrial DNA polymorphism and phylogenetic relationships in Hevea brasiliensis

Author:
Luo, H.; Coppenolle, B. van.; Seguin, M.; Boutry, M.
Source:
Molecular breeding 1995 v.1 no.1 pp. 51-63
ISSN:
1380-3743
Subject:
Hevea brasiliensis; restriction fragment length polymorphism; Vicia faba; mitochondrial DNA; chloroplast DNA; phylogeny; genetic distance; clones; genotype; genomics; chemotaxonomy; chloroplasts; Brazil; Colombia; Peru
Abstract:
... Using fourteen random mitochondrial DNA probes, we have examined restriction fragment length polymorphism (RFLP) in wild and cultivated Hevea brasiliensis. A total of 395 accessions, including 345 from various prospectings collected in Brazil, Colombia and Peru and 50 cultivated clones, were analyzed. Two other species (H. benthamiana and H. pauciflora) were also included in the study for comparis ...
DOI:
10.1007/BF01682089

8. Modern ticuna swidden-fallow management in the Colombian amazon: ecologically integrating market strategies and subsistence-driven economies?

Author:
Hammond, D.S.; Dolman, P.M.; Watkinson, A.R.
Source:
Human ecology 1995 v.23 no.3 pp. 335-356
ISSN:
0300-7839
Subject:
agriculture; production economics; shifting cultivation; fallow; farm management; objectives; rain forests; villages; modernization; Colombia; Brazil
DOI:
10.1007/BF01190136

9. Genetic resources of Centrosema spp.: genetic changes associated to the handling of an active collection

Author:
Penteado, M.I. de O.; Saenz, L.E.; Saenz de Miera, L.E.; Perez de la Vega, M.
Source:
Genetic resources and crop evolution 1996 v.43 no.1 pp. 85-90
ISSN:
0925-9864
Subject:
Centrosema acutifolium; Centrosema pubescens; Centrosema brasilianum; germplasm; plant genetic resources; isozymes; loci; genetic variation; genetic drift; agronomic traits; outcrossing; gene frequency; Brazil; Colombia
DOI:
10.1007/BF00126945

10. Diallel Analysis of Acid-Soil Tolerant and Intolerant Tropical Maize Populations

Author:
F. S. Salazar; S. Pandey; L. Narro; J. C. Perez; H. Ceballos; S. N. Parentoni; A. F. C. Bahia Filho
Source:
Crop science 1997 v.37 no.5 pp. 1457-1462
ISSN:
0011-183X
Subject:
heterosis; Zea mays; cultivars; plant development; acid soils; corn ears; fungal diseases of plants; ear rot; plant characteristics; height; diallel analysis; soil fertility; yield components; soil pH; Colombia; Brazil
Abstract:
... Acid soils cover approximately 30% of the global ice-free land area. Nearly 26 million hectares of maize (Zea mays L.) is already planted on acid soils. Maize yields are low on acidic soils because of toxicities of Al. Mn, and Fe, and deficiencies of P, Ca, Mg, and K. Acid-tolerant maize cultivars would be an environmentally friendly and relatively inexpensive method for improving maize production ...
DOI:
10.2135/cropsci1997.0011183X003700050007x

11. Genetic variability of Colletotrichum lindemuthianum in wild populations of common bean

Author:
Sicard, D.; Buchet, S.; Michalakis, Y.; Neema, C.
Source:
Plant pathology 1997 v.46 no.3 pp. 355-365
ISSN:
0032-0862
Subject:
Colletotrichum lindemuthianum; Phaseolus vulgaris; genetic variation; wild plants; virulence; biomarkers; genetic polymorphism; pathotypes; geographical variation; haplotypes; random amplified polymorphic DNA technique; Argentina; Brazil; Rwanda; Colombia; Europe
DOI:
10.1046/j.1365-3059.1997.d01-16.x

12. Isozyme and RAPD analysis of the genetic diversity within and between Vigna luteola anad V. marina

Author:
Sonnante, G.; Spinosa, A.; Marangi, A.; Pignone, D.
Source:
Annals of botany 1997 v.80 no.6 pp. 741-746
ISSN:
0305-7364
Subject:
random amplified polymorphic DNA technique; Vigna luteola; loci; enzyme polymorphism; genetic distance; genetic variation; allozymes; chemotaxonomy; Australia; Africa; Brazil; Mexico; Colombia
Abstract:
... Nineteen accessions of Vigna luteola, five of V. marina ssp. oblonga, and two of V. marina ssp. marina were analysed using variation of isozymes and RAPD markers to obtain better insight into genetic relationships within and between these taxonomic entities. Thirteen putative isozyme loci were scored, seven of which were polymorphic. Both species showed very low genetic diversity indices and most ...
DOI:
10.1006/anbo.1997.0511

13. Isozymic and metric variation in the Lutzomiya longipalpis complex

Author:
Dujardin, J.P.; Torrez, E.M.; Le Pont, F.; Hervas, D.; Sossa, D.
Source:
Medical and veterinary entomology 1997 v.11 no.4 pp. 394-400
ISSN:
0269-283X
Subject:
phenotype; Lutzomyia longipalpis; enzyme polymorphism; genetic distance; genetic variation; isozymes; wings; Brazil; Colombia; Bolivia; Nicaragua
Abstract:
... Male Lutzomyia longipalpis of two types from Bolivia were compared using isozyme electrophoresis and wing morphometry. One sample (ex Chiflonkaka Cave, alt. 2800 m at Toro Toro, Charcas Province, Potosi Department) was 'two-spot' phenotype males (i.e. tergites III and IV with paired pale patches of pheromone glands), whereas two other locality samples (Apa Apa and Imanaco, Sud Yungas Province, La ...
DOI:
10.1111/j.1365-2915.1997.tb00428.x

14. Tapeinostemon sessiliflorum (Gentianaceae), a new combination for a Guayana endemic

Author:
John F. Pruski; Stephen F. Smith
Source:
Brittonia 1997 v.49 no.3 pp. 346-349
ISSN:
0007-196X
Subject:
Gentianaceae; Rubiaceae; new combination; plant taxonomy; rare species; Brazil; Colombia; Venezuela
Abstract:
... A new combination,Tapeinostemon sessiliflorum (Gentianaceae), is made forPsychotria sessiliflora (Rubiaceae).Tapeinostemon capitatum is placed into synonymy ofT. sessiliflorum. This rare species occurs in the Guayanan region of Brazil, Colombia, and Venezuela. ...
DOI:
10.2307/2807834

15. A new dieback disease of the forage legume Stylosanthes guianensis in South America

Author:
Kelemu, S.; Badel, J.L.; Fernandes, C.D.
Source:
Canadian journal of plant pathology 1997 v.19 no.4 pp. 376-379
ISSN:
0706-0661
Subject:
etiology; cultivars; conidia; fungal diseases of plants; Deuteromycotina; varietal resistance; Stylosanthes guianensis; genotype; disease resistance; dieback; Brazil; Colombia
Abstract:
... A wilt and eventual dieback disease of the forage legume Stylosanthes guianensis, which occurs widely in Colombia and Brazil, is described. The causal agent of the wilt disease is identified as Lasiodiplodia theobromae, a virulent, unspecialized, facultative wound pathogen with worldwide distribution and more than 500 different host plants. The 1-septate conidia are slow maturing, brown, thick wal ...
DOI:
10.1080/07060669709501063

16. Mitochondrial DNA analysis of the neotropical malaria vector Anopheles nuneztovari

Author:
Conn, J.E.; Mitchell, S.E.; Cockburn, A.F.
Source:
Genome = 1998 v.41 no.3 pp. 313-327
ISSN:
0831-2796
Subject:
Anopheles nuneztovari; mitochondrial DNA; genetic variation; haplotypes; genetic distance; phylogeny; gene flow; Bolivia; Colombia; Suriname; Venezuela; Brazil
Abstract:
... Restriction endonucleases were used to test an hypothesis, based on cytological data, proposing the existence of two races in Anopheles nuneztovari, one Venezuelan-Colombian and the other Amazonian, and to examine variation in the mitochondrial DNA (mtDNA) of 263 individual A. nuneztovari mosquitoes from 12 sites in Bolivia, Brazil, Colombia, Suriname, and Venezuela. Cladistic analysis of the mtDN ...
DOI:
10.1139/g98-031

17. Identification of a novel source of resistance to angular leaf spot disease of common bean within the secondary gene pool

Author:
Busogoro, J.P.; Jijakli, M.H.; Lepoivre, P.
Source:
Plant breeding 1999 v.118 no.5 pp. 417-423
ISSN:
0179-9541
Subject:
Phaeoisariopsis griseola; hybrids; genetic resistance; Phaseolus coccineus; vertical resistance; Phaseolus vulgaris; leaf spot; genes; disease resistance; plant genetic resources; genotype; interspecific hybridization; Rwanda; Colombia; Kenya; Burundi; Brazil
Abstract:
... Phaeoisariopsis griseola (Sacc.) Ferr., the agent of angular leaf spot disease of common bean, is a highly variable pathogen for which resistance gene diversification is required. This study analysed genetic resistance to this disease within genotypes of three Phaseolus species. Twenty-nine genotypes of Phaseolus vulgaris, Phaseolus coccineus and Phaseolus polyanthus were inoculated with 54 isolat ...
DOI:
10.1046/j.1439-0523.1999.00413.x

18. Intragenomic heterogeneity of a ribosomal DNA spacer (ITS2) varies regionally in the neotropical malaria vector Anopheles nuneztovari (Diptera: Culicidae)

Author:
Onyabe, D.Y.; Conn, J.E.
Source:
Insect molecular biology 1999 v.8 no.4 pp. 435-442
ISSN:
0962-1075
Subject:
Anopheles nuneztovari; ribosomal DNA; nucleotide sequences; geographical variation; genome; males; females; population; intergenic DNA; Venezuela; Colombia; Brazil
Abstract:
... We investigated intragenomic heterogeneity of ITS2 within twenty individual Anopheles nuneztovari (subgenus Nyssorhynchus) from five geographical localities in the neotropics (three from Brazil and one each from Colombia and Venezuela) by cloning and sequencing PCR-amplified copies of this spacer. Intragenomic heterogeneity was observed in thirteen of twenty mosquitoes of both sexes from all local ...
DOI:
10.1046/j.1365-2583.1999.00134.x
PubMed:
10634969

19. Metaphase karyotypes and G‐banding in sandflies of the Lutzomyia longipalpis complex

Author:
Huaizhi Yin; J. ‐P. Mutebi; S. Marriott; G. C. Lanzaro
Source:
Medical and veterinary entomology 1999 v.13 no.1 pp. 72-77
ISSN:
0269-283X
Subject:
karyotyping; disease vectors; taxonomy; Lutzomyia longipalpis; chromosomes; chromosome banding; leishmaniasis; metaphase; Costa Rica; Brazil; Colombia
Abstract:
... Mitotic metaphase chromosomes (2n = 8) from brain cells of fourth instar sandfly larvae of four geographical strains of the Lutzomyia longipaplis complex were examined microscopically, with bright‐field illumination, after staining by a new G‐banding technique involving exposure of air‐dried chromosome preparations to quinacrine and ultraviolet light. Differences of G‐banding and/or position of th ...
DOI:
10.1046/j.1365-2915.1999.00139.x
PubMed:
10194752

20. Miospores from upper cretaceous‐Paleocene strata in northwestern Bolivia

Author:
Vivi Vajda‐Santivanez
Source:
Palynology 1999 v.23 no.1 pp. 181-196
ISSN:
1558-9188
Subject:
Angiospermae; Azolla; Botryococcus; Maastrichtian age; Paleocene epoch; algae; flora; fungal spores; megaspores; monosulcate pollen; tricolporate pollen; Bolivia; Brazil; Colombia; Venezuela
Abstract:
... Outcrop samples from the Flora and Eslabón formations from northwestern Bolivia contain abundant terrestrial palynomorphs. Pollen grains and spores of 49 species belonging to 36 genera were identified and two new pollen species — Psilaperiporites boliviensis and Psilaperiporites suarezi — are described. The Bolivian palynoflora consists mainly of monocolpate, tricolpate and tricolporate angiosperm ...
DOI:
10.1080/01916122.1999.9989527