A field experiment was conducted to assess side effects of insecti.:ide treatments on the tomato,... more A field experiment was conducted to assess side effects of insecti.:ide treatments on the tomato, Lycopersicon esculentum Miller, cv. Peto Seed 98, entomofauna, in the Limón river zone, State of Zulia, Venezuela, du-ling March-April 1992. Three convencional treatments (CT): methomyl (0.25% active ingredient [ai] vlv; acephato (0.19% ai wlv); and lambdacyhalotrin (0.006% ai vlv); a selective (ST): methomyl (0.1% ai vlv) + Bacillus thuringiensis Berliner (0.0032% ai wlv; 16.000 UPImg) and an untreated check (UC) were assessed utilizing a randomized block design with four replications. Population dynamics ofland damages by Liriomyza spp, Bemisia tabaci (Gennadius) and Keiferia lycopersicella (Walsigham) were utilize 4 as indicators. The % infestation and the number of mines by Liriomyza, were significantly lower (Pc.05) on UC, while the % parasitism was significantly higher on UC and ST. Populations and % infestation by B. tabaci resulted significantly higher under acephate followed by...
The Begomovirus are transmitted by Bemisia tabaci and cause major problems on tomato. The selecti... more The Begomovirus are transmitted by Bemisia tabaci and cause major problems on tomato. The selective use of effective systemic insecticides represents a management alternative. Thus, the interference of pre-transplant treatment of tomato seedlings with imidacloprid on the transmission of ToVEV by B. tabaci was assessed during January-April 2010. After soaking their substrate with: 1) water (check), or 2) imidacloprid (0.53 g i.a.·L-1), seedling were exposed to 100 viruliferous adults.plant-1 and then transplanted to pots. The percentage of
Rev. Fac. Agron. (LUZ). 1997, 14: 163-171. Modelos para estimar el área foliar de melón híbrido `... more Rev. Fac. Agron. (LUZ). 1997, 14: 163-171. Modelos para estimar el área foliar de melón híbrido `Durango'. l. Leaf area estimation models for `Durango' hybrid melon. l Aceptado el 29-11-1996 1. Unidad Técnica Fitosanitaria ...
Tomato yellow leaf curl virus (TYLCV), a member of the family Geminiviridae, is a serious product... more Tomato yellow leaf curl virus (TYLCV), a member of the family Geminiviridae, is a serious production constraint to tomato worldwide. In the new world, the virus had been identified as the causal agent of tomato yellow leaf curl disease in the Caribbean countries of the Dominican Republic, Cuba, and Guadeloupe and also in Florida and the Yucatan Peninsula (1). Molecular data from these TYLCV isolates identified the virus as the TYLCV prototype from Israel. During April 2004, tomato plants showing symptoms such as chlorotic leaf edges, upward leaf cupping, leaf mottling, and reduced leaf size indicative of TYLCV were observed in commercial fields in Zulia state, Venezuela. Whiteflies (Bemisia tabaci Gennadius) were present in the field and appeared to be associated with the disease. Leaf samples from nine symptomatic plants were collected and brought to the lab at Instituto Venezolano de Investigaciones Científicas (IVIC) for further analyses. Geminivirus infection of samples was confirmed by PCR amplification with the degenerate primer pair PAL1v1978 and PAR1c494 (2). TYLCV coat protein gene-specific primers KL04-06_TYLCV CP F and KL04-07_TYLCV CP R (3) were used to confirm the diagnosis. These primers amplified the expected 842-bp PCR product from the nine symptomatic samples. One of the resulting amplicons was cloned into the pCR-TOPO vector (Invitrogen, Carlsbad, CA) and sequenced (GenBank Accession No. DQ302033). Sequence comparison with those available in the NCBI database indicated that the sequenced portion of the genome shared 99% nucleotide identity with the TYLCV mild strain from Portugal (GenBank Accession No. AF105975) and 98% nucleotide identity with the TYLCV mild strain from Spain (GenBank Accession No. AF071228), TYLCV Israel isolate (GenBank Accession No. AM234066), and TYLCV Mexico isolate (GenBank Accession No. DQ631892). To our knowledge, this is the first report of TYLCV infecting tomato crops in South America. Further studies are needed to clarify how TYLCV has been introduced into Venezuela. References: (1) J. E. Polston and P. K. Anderson. Plant Dis. 81:1358, 1997. (2) M. R. Rojas et al. Plant Dis. 77:340, 1993. (3) K. S. Ling et al. Plant Dis. 90:379, 2006.
International audienceBegomoviruses are one of the major constraint for crop production in tropic... more International audienceBegomoviruses are one of the major constraint for crop production in tropical and subtropical regions. Euphorbia mosaic Venezuela virus (EuMVV) is a begomovirus first reported infecting milkweed (Euphorbia heterophylla) and tomato (Solanum lycopersicum) in Venezuela and displaying mild symptoms of yellowing and curling of leave. In this study seven tomato plants exhibiting begomovirus-like symptoms were collected in a field of Zulia, Venezuela. The samples were analysed by PCR using universal primers for begomoviruses. Begomovirus incidence was confirmed for all samples and sequencing of the expected viral DNA fragments revealed the presence of EuMVV in three samples. One of the EuMVV isolates was highly divergent when compared with previous reported isolates. In order to characterize this EuMMV isolate further assays were carried out to perform full-genome amplification and production of an infectious clone
Review of the history of the discovery, the taxonomy and the biological control of Capulinia lina... more Review of the history of the discovery, the taxonomy and the biological control of Capulinia linarosae (Hemiptera: Coccoidea: Eriococcidae)
Revista De La Facultad De Agronomia De La Universidad Del Zulia, 1998
Un estudio de reconocimiento de artropodos asociados con melon, Cucumis melo L. fue conducido en ... more Un estudio de reconocimiento de artropodos asociados con melon, Cucumis melo L. fue conducido en la zona noroccidental de Venezuela durante el periodo 1989-1994. Mediante recolecciones de campo y crias de laboratorio fueron identificados mas de 39 taxa infrafamilia (especies, generos o tribus) ubicados en 28 familias dentro de 9 ordenes. De estos taxa, 14 (34%) son de habitos fitofagos y 26 (66%) entomofagos (31% parasitoides y 35% depredadores). Para los artropodos de mayor relevancia se discuten aspectos ecologicos asi como sus implicaciones en el manejo de plagas del cultivo.
Revista De La Facultad De Agronomia De La Universidad Del Zulia, 1997
Durante septiembre-noviembre 1993 fue conducido un ensayo de campo para evaluar efectos colateral... more Durante septiembre-noviembre 1993 fue conducido un ensayo de campo para evaluar efectos colaterales del uso de insecticidas, sobre la entomofauna del melon, Cucumis melo L, al suroeste de la planicie de Maracaibo, estado Zulia, Venezuela. Los tratamientos evaluados fueron: endosulfan [0.22 % ingrediente activo (ia) v/v]; buprofezin (0.125 % ia p/v); monocrotofos (0.15 % ia v/v) y un testigo sin insecticidas. El diseno fue un bloques al azar con cuatro repeticiones. Como indicadores fueron evaluadas, en tres tipos de hoja (jovenes, maduras y senescentes), las poblaciones de Bemisia tabaci (Gennadius) y Aphis gossypii Glover. Las poblaciones de B. tabaci fueron significativamente mayores con monocrotofos mientras que el porcentaje de parasistismo fue mayor en el testigo y donde se aplico endosulfan. En cuanto a edades de hojas, el numero de ninfas y el porcentaje de parasitismo fueron significativamente mayores en hojas maduras y senescentes. A. gossypii fue detectado solo durante las...
A field experiment was conducted to assess side effects of insecti.:ide treatments on the tomato,... more A field experiment was conducted to assess side effects of insecti.:ide treatments on the tomato, Lycopersicon esculentum Miller, cv. Peto Seed 98, entomofauna, in the Limón river zone, State of Zulia, Venezuela, du-ling March-April 1992. Three convencional treatments (CT): methomyl (0.25% active ingredient [ai] vlv; acephato (0.19% ai wlv); and lambdacyhalotrin (0.006% ai vlv); a selective (ST): methomyl (0.1% ai vlv) + Bacillus thuringiensis Berliner (0.0032% ai wlv; 16.000 UPImg) and an untreated check (UC) were assessed utilizing a randomized block design with four replications. Population dynamics ofland damages by Liriomyza spp, Bemisia tabaci (Gennadius) and Keiferia lycopersicella (Walsigham) were utilize 4 as indicators. The % infestation and the number of mines by Liriomyza, were significantly lower (Pc.05) on UC, while the % parasitism was significantly higher on UC and ST. Populations and % infestation by B. tabaci resulted significantly higher under acephate followed by...
The Begomovirus are transmitted by Bemisia tabaci and cause major problems on tomato. The selecti... more The Begomovirus are transmitted by Bemisia tabaci and cause major problems on tomato. The selective use of effective systemic insecticides represents a management alternative. Thus, the interference of pre-transplant treatment of tomato seedlings with imidacloprid on the transmission of ToVEV by B. tabaci was assessed during January-April 2010. After soaking their substrate with: 1) water (check), or 2) imidacloprid (0.53 g i.a.·L-1), seedling were exposed to 100 viruliferous adults.plant-1 and then transplanted to pots. The percentage of
Rev. Fac. Agron. (LUZ). 1997, 14: 163-171. Modelos para estimar el área foliar de melón híbrido `... more Rev. Fac. Agron. (LUZ). 1997, 14: 163-171. Modelos para estimar el área foliar de melón híbrido `Durango'. l. Leaf area estimation models for `Durango' hybrid melon. l Aceptado el 29-11-1996 1. Unidad Técnica Fitosanitaria ...
Tomato yellow leaf curl virus (TYLCV), a member of the family Geminiviridae, is a serious product... more Tomato yellow leaf curl virus (TYLCV), a member of the family Geminiviridae, is a serious production constraint to tomato worldwide. In the new world, the virus had been identified as the causal agent of tomato yellow leaf curl disease in the Caribbean countries of the Dominican Republic, Cuba, and Guadeloupe and also in Florida and the Yucatan Peninsula (1). Molecular data from these TYLCV isolates identified the virus as the TYLCV prototype from Israel. During April 2004, tomato plants showing symptoms such as chlorotic leaf edges, upward leaf cupping, leaf mottling, and reduced leaf size indicative of TYLCV were observed in commercial fields in Zulia state, Venezuela. Whiteflies (Bemisia tabaci Gennadius) were present in the field and appeared to be associated with the disease. Leaf samples from nine symptomatic plants were collected and brought to the lab at Instituto Venezolano de Investigaciones Científicas (IVIC) for further analyses. Geminivirus infection of samples was confirmed by PCR amplification with the degenerate primer pair PAL1v1978 and PAR1c494 (2). TYLCV coat protein gene-specific primers KL04-06_TYLCV CP F and KL04-07_TYLCV CP R (3) were used to confirm the diagnosis. These primers amplified the expected 842-bp PCR product from the nine symptomatic samples. One of the resulting amplicons was cloned into the pCR-TOPO vector (Invitrogen, Carlsbad, CA) and sequenced (GenBank Accession No. DQ302033). Sequence comparison with those available in the NCBI database indicated that the sequenced portion of the genome shared 99% nucleotide identity with the TYLCV mild strain from Portugal (GenBank Accession No. AF105975) and 98% nucleotide identity with the TYLCV mild strain from Spain (GenBank Accession No. AF071228), TYLCV Israel isolate (GenBank Accession No. AM234066), and TYLCV Mexico isolate (GenBank Accession No. DQ631892). To our knowledge, this is the first report of TYLCV infecting tomato crops in South America. Further studies are needed to clarify how TYLCV has been introduced into Venezuela. References: (1) J. E. Polston and P. K. Anderson. Plant Dis. 81:1358, 1997. (2) M. R. Rojas et al. Plant Dis. 77:340, 1993. (3) K. S. Ling et al. Plant Dis. 90:379, 2006.
International audienceBegomoviruses are one of the major constraint for crop production in tropic... more International audienceBegomoviruses are one of the major constraint for crop production in tropical and subtropical regions. Euphorbia mosaic Venezuela virus (EuMVV) is a begomovirus first reported infecting milkweed (Euphorbia heterophylla) and tomato (Solanum lycopersicum) in Venezuela and displaying mild symptoms of yellowing and curling of leave. In this study seven tomato plants exhibiting begomovirus-like symptoms were collected in a field of Zulia, Venezuela. The samples were analysed by PCR using universal primers for begomoviruses. Begomovirus incidence was confirmed for all samples and sequencing of the expected viral DNA fragments revealed the presence of EuMVV in three samples. One of the EuMVV isolates was highly divergent when compared with previous reported isolates. In order to characterize this EuMMV isolate further assays were carried out to perform full-genome amplification and production of an infectious clone
Review of the history of the discovery, the taxonomy and the biological control of Capulinia lina... more Review of the history of the discovery, the taxonomy and the biological control of Capulinia linarosae (Hemiptera: Coccoidea: Eriococcidae)
Revista De La Facultad De Agronomia De La Universidad Del Zulia, 1998
Un estudio de reconocimiento de artropodos asociados con melon, Cucumis melo L. fue conducido en ... more Un estudio de reconocimiento de artropodos asociados con melon, Cucumis melo L. fue conducido en la zona noroccidental de Venezuela durante el periodo 1989-1994. Mediante recolecciones de campo y crias de laboratorio fueron identificados mas de 39 taxa infrafamilia (especies, generos o tribus) ubicados en 28 familias dentro de 9 ordenes. De estos taxa, 14 (34%) son de habitos fitofagos y 26 (66%) entomofagos (31% parasitoides y 35% depredadores). Para los artropodos de mayor relevancia se discuten aspectos ecologicos asi como sus implicaciones en el manejo de plagas del cultivo.
Revista De La Facultad De Agronomia De La Universidad Del Zulia, 1997
Durante septiembre-noviembre 1993 fue conducido un ensayo de campo para evaluar efectos colateral... more Durante septiembre-noviembre 1993 fue conducido un ensayo de campo para evaluar efectos colaterales del uso de insecticidas, sobre la entomofauna del melon, Cucumis melo L, al suroeste de la planicie de Maracaibo, estado Zulia, Venezuela. Los tratamientos evaluados fueron: endosulfan [0.22 % ingrediente activo (ia) v/v]; buprofezin (0.125 % ia p/v); monocrotofos (0.15 % ia v/v) y un testigo sin insecticidas. El diseno fue un bloques al azar con cuatro repeticiones. Como indicadores fueron evaluadas, en tres tipos de hoja (jovenes, maduras y senescentes), las poblaciones de Bemisia tabaci (Gennadius) y Aphis gossypii Glover. Las poblaciones de B. tabaci fueron significativamente mayores con monocrotofos mientras que el porcentaje de parasistismo fue mayor en el testigo y donde se aplico endosulfan. En cuanto a edades de hojas, el numero de ninfas y el porcentaje de parasitismo fueron significativamente mayores en hojas maduras y senescentes. A. gossypii fue detectado solo durante las...
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