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At least two indigenous species of the Bemisia tabaci complex are present in Brazil

Marubayashi, J. M.; Yuki, V. A.; Rocha, K. C G; Mituti, T.; Pelegrinotti, F. M.; Ferreira, F. Z.; Moura, M. F.; Navas-Castillo, J.; Moriones, E.; Pavan, M. A.; Krause-Sakate, R.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 113-121
ENG
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Bemisia tabaci is one of the most important global agricultural insect pests, being a vector of emerging plant viruses such as begomoviruses and criniviruses that cause serious problems in many countries. Although knowledge of the genetic diversity of B. tabaci populations is important for controlling this pest and understanding viral epidemics, limited information is available on this pest in Brazil. A survey was conducted in different locations of São Paulo and Mato Grosso states, and the phylogenetic relationships of B. tabaci individuals from 43 populations sampled from different hosts were analysed based on partial mitochondrial cytochrome oxidase 1 gene (mtCOI) sequences. According to the recently proposed classification of the B. tabaci complex, which employs the 3.5% mtCOI sequence divergence threshold for species demarcation, most of the specimens collected were found to belong to the Middle East-Asia Minor 1 species, which includes the invasive populations of the commonly known B biotype, within the Africa/Middle East/Asia Minor high-level group. Three specimens collected from Solanun gilo and Ipomoea sp. were grouped together and could be classified in the New World species that includes the commonly known A biotype. However...

Plant-derived essential oils affecting settlement and oviposition of Bemisia tabaci (Genn.) biotype B on tomato

Baldin, Edson L.L.; Crotti, Antônio E.M.; Wakabayashi, Kamila A.L.; Silva, José P.G.F.; Aguiar, Gabriela P.; Souza, Efrain S.; Veneziani, Rodrigo C.S.; Groppo, Milton
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 301-308
ENG
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The silverleaf whitefly Bemisia tabaci (Genn.) biotype B (Hemiptera: Aleyrodidae) is an economically important pest of tomatoes Solanum lycopersicum (L.), causing irregular ripening on fruits and transmitting several plant pathogenic geminiviruses. The management of this pest is commonly based on repetitive spraying with synthetic pesticides, causing serious environmental damages and increase of resistance by insect population. In the present study, essential oils from the leaves of Artemisia camphorata Vill., Ageratum conyzoides L., Foeniculum vulgare Mill., Lippia alba (Mill.) N. E. Br., Plectranthus neochilus Schltr., and Tagetes erecta L. were investigated for their possible repellent and oviposition-deterrent effects against B. tabaci biotype B on tomato. In a multi-choice assay, P. neochilus essential oil was the most active repellent and oviposition deterrent. Essential oils of A. conyzoides and T. erecta significantly deterred the female B. tabaci biotype B from laying eggs on treated tomato leaflets compared with the control. (E)-Caryophyllene (30.67 %) and the monoterpenes α-pinene (15.02 %) and α-thujene (11.70 %) were identified as the major constituents of the essential oil of P. neochilus. Our findings demonstrated the potential of essential oil of P. neochilus and other oils in the reduction of settlement and oviposition of B. tabaci biotype B on tomato. © 2012 Springer-Verlag Berlin Heidelberg.

Indigenous American species of the Bemisia tabaci complex are still widespread in the Americas

Barbosa, Leonardo da F.; Marubayashi, Julio M.; De Marchi, Bruno R.; Yuki, Valdir A.; Pavan, Marcelo A.; Moriones, Enrique; Navas-Castillo, Jesus; Krause-Sakate, Renate
Fonte: Wiley-Blackwell Publicador: Wiley-Blackwell
Tipo: Artigo de Revista Científica Formato: 1440-1445
ENG
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Processo FAPESP: 10/17313-3; Processo FAPESP: 13/12377-1; Processo FAPESP: 12/17373-1; Bemisia tabaci is a complex of at least 36 putative cryptic species. Since the late 1980s, the Middle East-Asia Minor 1 species (MEAM1, formerly known as the B biotype), has emerged in many tropical and subtropical regions of the world and in some areas has displaced the indigenous populations of B. tabaci. Based on analysis of the mtCOI gene, two indigenous species native to America have been reported: New World (NW, formerly the A biotype) and New World 2 (NW2). NW is present at least in Argentina, Brazil, Martinique, Mexico, Texas and Venezuela, and NW2 in Argentina, Bolivia and Brazil. Wild plants (Euphorbia sp. and Ipomoea sp.), as well as important crops such as tomato, bean and cotton, are still hosts for native B. tabaci populations in the Americas. MEAM1 has not completely displaced the native B. tabaci from the Americas. (C) 2014 Society of Chemical Industry

Presença e impacto de Bemisia tabaci (Genn.) (Homoptera: aleyrodidae) em culturas hortícolas em Portugal

Mexia, António; Mateus, Célia; Amaro, Fernanda; Louro, Diamantina
Fonte: Sociedade de Ciências Agrárias de Portugal Publicador: Sociedade de Ciências Agrárias de Portugal
Tipo: Artigo de Revista Científica
Publicado em //2008 POR
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In Portugal, Bemisia tabaci (Genn.) (Homoptera: Aleyrodidae) was first recorded in 1992, in horticultural crops. Since 1995, it has been an important pest in the Algarve, southern Portugal, where it is present the whole year round, in greenhouse crops, with high infestations during the summer. In 2006, it was installed in Alentejo and in part of Ribatejo e Oeste region. It is a serious problem to several vegetable crops, due to direct damages, but mainly by transmitting plant viruses. The most severely affected crops are greenhouse tomato and cucurbits. IPM is considered the best way to deal with the sustainable management of this problem, but the presence of viruses complicates the implementation of IPM programs. The work presented here gives an overview of the results obtained by the research activities carried out in Portugal concerning B. tabaci: geographical distribution, bioecology, biotypes identification, virus transmission, risk assessment, natural enemies’ survey and control methods. Future research work is suggested.

Atividade ovicida de extratos aquosos de meliáceas sobre a mosca branca Bemisia tabaci (Gennadius) biótipo B em tomateiro

Souza,Antonio Pancrácio de; Vendramim,José Djair
Fonte: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz" Publicador: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz"
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2000 PT
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A mosca branca Bemisia tabaci (Gennadius) biótipo B atualmente é uma das principais pragas do tomateiro. O uso de extratos botânicos no controle desse inseto é uma alternativa promissora, mas que ainda precisa ser melhor pesquisada. O presente trabalho teve como objetivo determinar a bioatividade de extratos aquosos de folhas de Melia azedarach L. e de ramos de Trichilia pallida Swartz, sobre a mosca branca Bemisia tabaci (Gennadius) biótipo B, criada em tomateiro. Foram realizados dois experimentos, avaliando-se a mortalidade e duração das fases de ovo e ninfa, após o tratamento da fase de ovo com os referidos extratos. No primeiro experimento, foram testadas as concentrações de 1 e 2% (p/v), acrescentando-se a concentração de 3% no segundo experimento. Em todos os tratamentos houve efeito ovicida, sendo o maior valor obtido com T. pallida a 3% (52,32%). Nos demais tratamentos, a mortalidade variou entre 16 e 37%. Os extratos aplicados sobre os ovos pouco afetaram a sobrevivência ninfal. Com exceção do tratamento com T. pallida a 2%, no primeiro experimento, em que a mortalidade ninfal foi de 26,42%, nos demais a mortalidade foi inferior a 16%. Em nenhum dos experimentos foi verificada alteração na duração dos períodos de incubação e ninfal.

Biological traits and Life table parameters A and B biotype of Bemisia tabaci (Genn.) on cotton and rapeseed

Samih,Mohammad Amin; Zarabi,Mehdi; Yazdani,Maryam; Rouhani,Mohammad
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2014 EN
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The aim of this work was to construct life table of Bemisia tabaci (Gen.) A and B (silverleaf whitefly B. argentifolii Bellows and Perring) biotype (Hem.: Aleyrodidae) on two host plants; cotton, (Gossypium hirsutum L.) and rapeseed, (Brassica napus L.). Experiments were conducted in a growth chamber under 24 ± 2ºC, 55±3% RH and 16:8 (L:D) h photoperiod on caged plants of cotton G. hirsutum L. (Varamin 76 variety) and rapeseed B. napus L. (global variety. The intrinsic rate of natural increase (r m), net reproductive rate (R0) and mean generation time (T) for B. tabaci A biotype was 0.1010 females per female per day, 18.4075 females per female and 30.079 day (d) on cotton; 0.1286, 30.6760 and 26.77 d on rapeseed; and for B biotype (B. argentifolii) those above respective parameters averaged 0.1033, 27.8426 and 32.74 d on cotton and 0.1750, 40.75 and 21.27 d on rapeseed. The total survival of A and B biotype from the egg to adult on cotton was 22.08 and 22.25, respectively. The results showed significant differences between the two biotype reared on either host plant for gross reproductive rate (GRR), net reproductive rate (R0 or NRR), intrinsic rates of increase (r m), finite rate of increase (λ), doubling time (DT) and mean generation times (Tc). To obtain a better understanding of the biology of these biotypes...

Nutrição do tomateiro e a sua influência na preferência para abrigo, alimentação e oviposição de Bemisia tabaci (GENN.) biótipo B; Nutrition of the tomato and her influence in the preference for shelter, feeding and oviposition of Bemisia tabaci (Genn.) biotype B

OLIVEIRA, Marcos Fernandes
Fonte: Universidade Federal de Goiás; BR; UFG; Mestrado em Agronomia; Ciências Agrárias Publicador: Universidade Federal de Goiás; BR; UFG; Mestrado em Agronomia; Ciências Agrárias
Tipo: Dissertação Formato: application/pdf
POR
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Bemisia tabaci biotype B presently constitutes a great threat not only for the tomato crop but to several other cultures. The objective of this research was to evaluate the influence of the nutrition of tomato in the resistance induction for shelter, feeding and oviposition of B. tabaci biotype B. The experiments were driven in Escola de Agronomia e Engenharia de Alimentos (EA/UFG), Goiânia, Goiás, Brasil. Three experiments were accomplished outdoors in temperature conditions, humidity and natural photoperiod. In the first different sources of nitrogen were tested, in the second different ratios nitrogen/potassium and in the third party different associations between corrected soil and earthworm manure. Each experiment was subdivided in: with choice chance and without chance of choice of the insect, the first one was carried out on randomized blocks design and the second one completely randomized design. Each treatment had four replications, with one plant per pot. In the first experiment the treatments used were: corrected soil (without addition of fertilizers); potassium saltpeter; urea; phosphate monoamonic; nitrate of calcium; sulfate of ammonium; chicken manure; bone flour; castor oil plant pie; composed organic; and earthworm manure. In the second experiment the ratios were compared N/K: 1/1; 2/1; 4/1; 8/1; 1/2; 1/4; and 1/8. In the third experiment the associations corrected soil were compared + earthworm manure: 100% + 0%; 80% + 20%; 60% + 40%; 40% + 60%; 20% + 80%; 0% + 100%. Five evaluations on the observation of the behavior of B. tabaci biotype B in relation to the feeding preference and shelter were accomplished: 3...

First report of Bemisia tabaci Mediterranean (Q biotype) species in Brazil

Barbosa, Leonardo da Fonseca; Yuki, Valdir Atsushi; Marubayashi, Julio Massaharu; De Marchi, Bruno Rossitto; Perini, Fernando Luis; Pavan, Marcelo Agenor; Barros, Danielle Ribeiro de; Ghanim, Murad; Moriones, Enrique; Navas-Castillo, Jesus; Krause-Sakate,
Fonte: Wiley-Blackwell Publicador: Wiley-Blackwell
Tipo: Artigo de Revista Científica Formato: 501-504
ENG
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Processo FAPESP: 2013/12377-1; Processo FAPESP: 2012/17373-1; BACKGROUND: The whitefly Bemisia tabaci is amajor cosmopolitan pest and comprises a complex of more than 36 cryptic species that cause serious damage to agricultural crops worldwide. In this study, the Mediterranean species of B. tabaci, formerly known as Q biotype, was identified for the first time in Brazil.RESULTS: Adult B. tabaci were collected from different localities and hosts from Rio Grande do Sul, the southernmost state of the country that borders Uruguay and Argentina. Partial sequencing of the mitochondrial cytochrome oxidase I (mtCOI) gene indicated that B. tabaci MED species appears to be restricted to the province of Barra do Quarai, infesting Capsicum annuum cultivated in greenhouses and Ipomoea batatas in open fields. The partial mtCOI sequences obtained shared 100% nucleotide identity with reference sequences for the Q biotype reported from Uruguay. The secondary endosymbionts Hamiltonella and Cardinium were detected by PCR in the new identified MED species from Brazil, similarly to the Q biotype from Uruguay.CONCLUSION: Our results indicate the presence of the MED species in Brazil. The close monitoring of this new identified species in the southern region of Brazil is essential to avoid its geographical expansion to more important agricultural areas in the country. (C) 2014 Society of Chemical Industry

Analysis by DC –EPG of the resistance to Bemisia tabaci  on a Mi-tomato line

Jiang, Y-X.; Nombela, Gloria; Muñiz, M.
Fonte: Conselho Superior de Investigações Científicas Publicador: Conselho Superior de Investigações Científicas
Tipo: Artículo Formato: 95108 bytes; application/pdf
ENG
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The tomato Mi gene confers resistance to nematodes, Meloidogyne spp., and to the potato aphid,  Macrosiphum euphorbiae (Thomas). Previous greenhouse choice assays with Bemisia tabaci (Gennadius) showed that tomato commercial varieties carrying this gene had significantly lower values of host suitability and whitefly reproduction than varieties lacking Mi. This indicated that Mi, or another gene in its region, could regulate partial resistance. In order to characterise this resistance, probing and feeding behaviour of Bemisia tabaci B-biotype was studied with DC Electrical Penetration Graph (EPG) technique on the near-isogenic tomato lines Moneymaker (without Mi) and Motelle (carrying Mi). Significant differences (P<0.05) between tomato lines were found in EPG parameters related to epidermis and/or mesophyll tissues. On Motelle, a lower percentage of whiteflies achieved phloem phase and they made more probes before attaining first phloem phase, had a higher ratio (number of probes before first phloem phase)/(total number of probes), had a longer total duration of non-probing time, and a longer time before making the first intracellular puncture and before making the first phloem phase. In contrast, most of the parameters related to phloem phase were found not to differ significantly between these near-isogenic lines. The behavioural data strongly suggest that the partial resistance in the variety Motelle is due to factors in the epidermis and/or mesophyll that inhibit the whiteflies from reaching phloem sieve elements.  However...

A differential interaction study of   Bemisia tabaci Q-biotype on commercial tomato varieties bearing or not bearing the Mi resistance gene, and comparative host responses with the B-biotype

Nombela, Gloria; Beitia, F.; Muñiz, M.
Fonte: Conselho Superior de Investigações Científicas Publicador: Conselho Superior de Investigações Científicas
Tipo: Artículo Formato: 90516 bytes; application/pdf
ENG
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Three tomato varieties (Motelle, Ronita, and VFN8) bearing the Mi-1.2 gene providing resistance to nematodes Meloidogyne spp. and to the potato aphid Macrosiphum euphorbiae Thomas, and three varieties not bearing this gene (Moneymaker, Roma, and Río Fuego), were compared by choice assay for host preference using the Qbiotype of Bemisia tabaci (Gennadius). The most preferred hosts, determined by infestation levels and numbers of feeding adults were Moneymaker, Río Fuego and Roma, all of which were not carrying the Mi gene. Ronita and Motelle, both of which bore the Mi gene, were the least preferred hosts. In a no-choice assay, B. tabaci females laid a significantly lower number of eggs on the varieties that carried the Mi gene than on those lacking the gene. Differences were more dramatic when plants carrying the Mi gene were pooled together and compared with pooled plants without this gene. Significantly greater values were obtained for the Mi-lacking group for all parameters tested. Comparing these results with those from a previous study on the B-biotype of B. tabaci, Q-biotypes were found to produce higher daily infestation rates on most of the tomato varieties. When results from plants carrying Mi were pooled, they showed lower infestation levels of Q-biotypes than B-biotypes. The Q-biotype infested less Mi-plants and more non-Mi plants than B-biotype. Q-biotype females produced significantly less pupae than the B-biotype females on both groups of plants. These results suggest the existence of an antixenosis and antibiosisbased resistance to the Q-biotype of B. tabaci in Mi-bearing commercial tomato varieties...

Variation in tomato host response to Bemisia tabaci (Hemiptera: Aleyrodidae) in relation to acyl sugar content and presence of the nematode and potato aphid resistance gene Mi

Nombela, Gloria; Beitia, F.; Muñiz, M.
Fonte: Conselho Superior de Investigações Científicas Publicador: Conselho Superior de Investigações Científicas
Tipo: Artículo Formato: 169646 bytes; application/pdf
ENG
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Two commercial cultivars of tomato, Alta and Peto 95, the accession line number LA716 of Lycopersicon pennellii and lines 94GH-006 and 94GH-033 (backcrosses between Peto 95 and LA716), with different leaf acyl sugar contents were screened for resistance to Bemisia argentifolii Bellows & Perring (corresponding to the Spanish B-biotype of Bemisia tabaci (Gennadius), in greenhouse- and field-no-choice experiments. There was no oviposition on LA716 (with the highest acyl sugar content) while the greatest fecundity and fertility values were observed on the cultivar Alta (no acyl sugar content). However, no clear relationship was found between the low acyl sugar content in the other tomato cultivars tested and whitefly reproduction. Thus, resistance to B. tabaci did not appear to correlate with acylsugar content below a threshold level of 37.8 μg cm2 leaf. In a greenhouse choiceassay, B. tabaci exhibited reduced host preference and reproduction on the commercial tomato cultivars Motelle, VFN8 and Ronita all of which carry the Mi gene resistance to Meloidogyne nematodes and the aphid Macrosiphum euphorbiae Thomas),than on the Mi-lacking cultivars Moneymaker, Rio Fuego and Roma. When data of Mi-bearing plants were pooled, the mean values for daily infestation and pupal production of B. tabaci were significantly lower than those of Mi-lacking plants. This reflected a level of antixenosis- and antibiosis-based resistance in commercial tomato and indicated that Mi...

Comparison of three trap types for adult catching of whitefly Bemisia tabaci and its parasitoid Eretmocerus mundus in tomato greenhouse

Nombela, Gloria; Chu, CC.; Heneberry, T.; Muñiz, M.
Fonte: Conselho Superior de Investigações Científicas Publicador: Conselho Superior de Investigações Científicas
Tipo: Artículo Formato: 207217 bytes; application/pdf
ENG
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The attractiveness of three trap types to Bemisia tabaci (Gennadius) B-biotype (= Bemisia argentifolii Bellows & Perring) and Eretmocerus mundus Mercet adult was compared in two choice experiments in a greenhouse at the Centro de Ciencias Medioambientales, Madrid, Spain.  Yellow sticky cards equipped with light-emitting-diodes (LED-YC) caught more adults per trap per day than yellow sticky card (YC) traps.YC traps caught significantly more B. tabaci and E. mundus adults than plastic cup traps equipped with light-emitting diodes (LED-plastic cup traps).  However, the LED-plastic cup traps caught few E. mundus compared with YC traps.  The results suggest that LED-plastic cup traps are compatible with E. mundus parasites in greenhouses where the parasites are released to reduce B. tabaci nymph population.; Peer reviewed

Probing and Feeding Behavior of Two Distinct Biotypes of Bemisia tabaci (Homoptera: Aleyrodidae) on Tomato Plant

Jiang, Y-X.; Lei, H.; Collar, J. L.; Martín, B.; Muñiz, M.; Fereres, Alberto
Fonte: Conselho Superior de Investigações Científicas Publicador: Conselho Superior de Investigações Científicas
Tipo: Artículo Formato: 458192 bytes; application/pdf
ENG
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The probing and feeding behavior of 2 biotypes (B and Q)of the sweetpotato whitefly, Bemisia tabaci (Gennadius), were monitored using the electrical penetration graph (EPG) technique on tomato, Lycopersicon esculentum (Mill) ("Riofuego"). Seven EPG waveform patterns were distinguished. B. tabaci (B biotype) showed a shorter duration of potential drop pattern (4.73±0.45s) [mean ± SE], n=125), longer time to reach the phloem (209 ± 23.42min, n=22), and more complex pathway patterns than the greenhouse whiteßy, Trialeurodes vaporariorum (Westwood). Some differences were observed in feeding behavior of the 2 B. tabaci biotypes (B and Q) tested. Interestingly, significant differences (P<0.05) were found in those parameters related with phloem events: total duration of the E(pd), E(pd)1, and E(pd)2 (P,0.01), as well as mean duration of E(pd)and E(pd)2. In addition, there also were significant differences in the total number of probes (P<0.05). The Q biotype showed fewer number of probes and a longer phloem ingestion time (pattern E(pd)2) than those from the B biotype. Hence, our results revealed a clear difference in the probing and feeding behavior between the B and the Q biotypes of B. tabaci on tomato plants.; Peer reviewed

Capacidad de infestación en invernadero de los biotipos B y Q de Bemisia tabaci (Gennadius) en plantas de tomate con y sin el gen Mi

Baraja, M.J.; Manchón, M.A.; Nombela, Gloria; Muñiz, M.; Beitia, F.
Fonte: Conselho Superior de Investigações Científicas Publicador: Conselho Superior de Investigações Científicas
Tipo: Artículo Formato: 3990583 bytes; application/pdf
SPA
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Se han realizado experimentos de libre elección en condiciones de invernadero para obtener la relación entre el porcentaje de plantas de tomate infestadas (y) y el número de adultos de los biotipos By Qde Bemisia tabaci Gennadius(x) mediante la función linealz=-ax,siendo z= ln[1-(y/100)], utilizándose variedades de estecultivo con y sin elgen Mi de resistencia a nematodos del género Meloidogyne y al áfido de la patata, Macrosiphum euphorbiae (Thomas). Tanto el número medio de adultos como el porcentaje medio de infestación fue menor en las plantas con el gen Mi. Considerando todas las variedades conjuntamente, se observó una mayor capacidad de infestación del biotipo B que del Q.; Choice greenhouse assays were conducted to determine the relationship betwee percentage of infested tomato plants (y) and the number of adulls of the B and Q biotypes of Bemisia tabaci Gennadius (x). We used the linear function z=-ax,where z=ln[l-(y/l00)]. Tomato cultivars with and without the Mi gene which confers resistance to root-knol nematodes (Meloidogyne spp.)and to the potato aphid Macrosiphum euphorbiae (Thomas) were used in this study. The mean number of insects and the percentage of infestation on the Mi-bearing plants were shorter than were on the Mi-lacking plants.Considering all cultivars...

Preinfestations of tomato plants by whiteflies (Bemisia tabaci) or aphids (Macrosiphum euphorbiae) induce variable resistance or susceptibility responses

Nombela, Gloria; Garzo, E.; Duque, M.; Muñiz, M.
Fonte: Cambridge University Press Publicador: Cambridge University Press
Tipo: Artículo Formato: 109898 bytes
ENG
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In addition to constitutive plant resistance against pests or pathogens, plants can activate protective mechanisms upon contact with an invader or a chemical elicitor. Studies on induced plant resistance to herbivores, especially piercingsucking insects, are less abundant than those devoted to pathogens. Several experiments under controlled conditions have been conducted to demonstrate that infestations by Macrosiphum euphorbiae induce plant resistance to Bemisia tabaci in susceptible tomato plants. After three days of exposure to 20 apterous adult aphids, the plants acquired a transiently induced resistance to B. tabaci when aphid removal occurred one or 18 hours prior to B. tabaci infestation; the effect disappeared when four days passed between aphid and whitefly infestations. The resistance observed was both locally and systemically induced. Other assays were performed to evaluate the effect of preinfestation with ten adults of B. tabaci during 48 h on the tomato responses to two different clones (Sp and Nt) of M. euphorbiae. The numbers of nymph and adult aphids were counted after the same time interval as the pre-reproductive period and 20 (Sp clone) or 22 (Nt clone) days after adult aphid removal. The tomato responses induced by whitefly feeding depend on the aphid clone. For the Sp clone...

Phylogenetic relationships of world populations of Bemisia tabaci (Gennadius) using ribosomal ITS1

De Barro, Paul; Driver, Felice; Trueman, John; Curran, John
Fonte: Academic Press Publicador: Academic Press
Tipo: Artigo de Revista Científica
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A phylogeny of Bemisia tabaci is presented based on the ITS1 region of ribosomal DNA. The monophyly of each biotype of Bemisia is supported, and strong biogeographic pattern is evident in the data. Populations from the Americas (including the A biotype) form a clade sister to a clade comprising the silverleafing or B biotype and a nonsilverleafing biotype from the North Africa/Mediterranean region. Polymorphism in rDNA suggest that silverleafing is a recent phenomenon, while the nonsilverleafing form is the ancestral or plesiomorphic state. Based on this phylogeny, if B. argentifolii is accepted as a separate species then one would have to review the taxonomic status of all bio-types of B. tabaci. In particular, a new name clearly would be needed for an Egypt/Spain/Sudan/Nigeria clade, and the monophyly of the haplotypes remaining in B. tabaci would be open to serious doubt. To make new species assignments in these circumstances seems premature. The phylogenetic relationships of the different populations of B. tabaci and the origins of effective natural enemies of the B biotype suggest that knowing the origin of the B biotype is not essential to finding effective agents and supports the notion that crop management is the key aspect to control. (C) 2000 Academic Press.

Actividad fagodisuasiva de las plantas Tithonia diversifolia y Montanoa hibiscifolia (Asteraceae) sobre adultos del insecto plaga Bemisia tabaci (Homoptera: Aleyrodidae)

Bagnarello,Gina; Hilje,Luko; Bagnarello,Vanessa; Cartín,Víctor; Calvo,Marco
Fonte: Revista de Biología Tropical Publicador: Revista de Biología Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2009 ES
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Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae) es una plaga polífaga, cosmopolita y de gran relevancia mundial, sobre todo como vector de virus en numerosos cultivos, por lo que sería deseable un enfoque preventivo para su manejo. En tal sentido, podría recurrirse a la utilización de sustancias repelentes o disuasivas, algunas de ellas presentes en plantas tropicales, lo cual contribuiría al aprovechamiento de la rica biodiversidad mesoamericana. Por tanto, se evaluó la posible actividad fagodisuasiva sobre los adultos de B. tabaci de dos especies silvestres de la familia Asteraceae: titonia (Tithonia diversifolia (Hemsl.) A. Gray) y tora (Montanoa hibiscifolia Benth.). Para ello, en condiciones de invernadero se evaluaron los extractos crudos y cuatro fracciones (hexano, diclorometano, acetato de etilo y metanol) de ambas especies, a los cuales se les hizo un análisis fitoquímico (tamizaje) el cual permitió determinar cuáles metabolitos presentes en T. diversifolia y M. hibiscifolia podrían causar fagodisuasión en B. tabaci. Se realizaron dos tipos de experimentos: de escogencia restringida y de escogencia irrestricta. En los primeros, cada fracción se evaluó a cuatro dosis (0.1, 0.5, 1.0 y 1.5% v/v), y se comparó con cuatro tratamientos testigo: aceite agrícola...

Antifeedant activity of botanical crude extracts and their fractions on Bemisia tabaci (Homoptera: Aleyrodidae) adults: III. Quassia amara (Simaroubaceae)

Flores,Guillermo; Hilje,Luko; Mora,Gerardo A; Carballo,Manuel
Fonte: Revista de Biología Tropical Publicador: Revista de Biología Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2008 EN
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67.28%
Bemisia tabaci is a key virus vector on several crops worldwide. Then, a preventive approach to deal with viral epidemics may be the deployment of repellents or phagodeterrents at earlier stages of plant development (critical period). Thus, the crude extract and four fractions thereof (water, water: methanol, methanol, and diethyl ether) of bitterwood (Quassia amara, Simaroubaceae) were tested for phagodeterrence to B. tabaci adults under greenhouse conditions, on tomato plants, in Costa Rica. Both restricted-choice and unrestricted-choice experiments showed that the crude extract and some fractions exerted such effect on the insect. In the former case (in sleeve cages), all fractions caused deterrence at doses as low as 0.1 % (methanol), 0.5 % (water: methanol and diethyl ether), and 1% (water). In the latter case (plants exposed in a greenhouse) the methanol fraction stood out, followed by the diethyl ether fraction. Nonetheless, none of the fractions performed better than the deterrent control (mineral oil). Rev. Biol. Trop. 56 (4): 2131-2146. Epub 2008 December 12.

Efecto de niveles de humedad en el crecimiento y potencial hídrico de Capsicum chinense Jacq. Y su relación con el desarrollo de Bemisia tabaci Genn

May-Lara,Cesar; Pérez-Gutiérrez,Alfonzo; Ruiz-Sánchez,Esaú; Ic-Caamal,Alex E.; García-Ramírez,Alejandro
Fonte: Universidad Autónoma de Yucatán, Facultad de Medicina Veterinaria Publicador: Universidad Autónoma de Yucatán, Facultad de Medicina Veterinaria
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2011 ES
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67.24%
Se evaluó el efecto de niveles de humedad aprovechable en el crecimiento de plantas de Capsicum chinence Jacq., y en la supervivencia y desarrollo de Bemisia tabaci Genn. Se compararon cuatro tratamientos 60%, 50%, 40% y 30% de humedad aprovechable, calculados a partir del valor de la lámina de riego y del área del contenedor de la planta. Se registró la altura y diámetro del tallo, masa seca total, contenido de humedad de sustrato, potencial hídrico y uso eficiente del agua de la planta. Para evaluar el efecto de la condición hídrica de C. chínense en B. tabaci, se contabilizó el número de huevos ovipositados, mortalidad de huevos y ninfas y el tiempo medio de desarrollo de ninfas. Se encontró una correlación directa positiva entre el nivel de humedad aprovechable y el potencial hídrico foliar, ya que las plantas del tratamiento con mayor nivel de humedad aprovechable tuvieron significativamente mayor altura, diámetro de tallo y biomasa seca. Se encontró mayor oviposición y menor tiempo de desarrollo de ninfas de B. tabaci en plantas del tratamiento con 50% de humedad aprovechable. No se observó efecto de los niveles de humedad aprovechable en la mortalidad de huevos y ninfas de B. tabaci.

Atracción de adultos y preferencia de oviposición de mosquita blanca (Bemisia tabaci) en genotipos de Capsicum annuum

Chan Cupul,Wilberth; Ruiz Sánchez,Esau; Chan Díaz,Juan Rogelio; Latournerie Moreno,Luis; Rosado Calderón,Agatha Teresa; González Mendoza,Daniel
Fonte: Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias Publicador: Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2014 ES
Relevância na Pesquisa
67.24%
La mosquita blanca (Bemisia tabaci) es una plaga que limita el desarrollo de un gran número de cultivos hortícolas por la succión de savia y transmisión de begomovirus. Con el objetivo de encontrar algunas fuentes de resistencia se evaluó la atracción de adultos y preferencia de oviposición de B. tabaci en genotipos regionales de C. annuum colectados en el sureste de México. Se observó significativamente (p= 0.006) menor atracción de adultos en el genotipo Maax ik (0.6 y 0 adultos cm² a las 24 y 48 h de exposición) comparado con el genotipo comercial Jalapeño (8.2 y 4.2 adultos cm² a las 24 y 48 h de exposición). De igual manera se registró que B. tabaci presentó significativamente (p= 0.048) menor preferencia de oviposición en el follaje del genotipo Maax ik (0.5 y 0.7 huevos cm² a las 24 y 48 h de exposición) comparado con la preferencia al genotipo Jalapeño (12 y 16.5 huevos cm² a las 24 y 48 h de exposición). El genotipo de chile regional Maax ik puede ser usado como fuente de resistencia a B. tabaci en programas de mejoramiento genético de C. annuum.