Navegando por Autor "Bacci, Leandro"

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Acaricidal properties of vetiver essential oil from Chrysopogon zizanioides (Poaceae) against the tick species Amblyomma cajennense and Rhipicephalus (Boophilus) microplus (Acari: Ixodidae)
(Veterinary Parasitology, 2015-08-20) Campos, Roseane Nunes de Santana; Lima, Cecília Beatriz Nascimento; Oliveira, Alexandre Passos; Araújo, Ana Paula Albano; Blank, Arie Fitzgerald; Alves, Péricles Barreto; Lima, Rafaely Nascimento; Araújo, Vinícius Albano; Santana, Alisson Silva; Bacci, Leandro
Ticks are arthropods widely distributed in tropical and subtropical regions, which can transmit infectious agents also responsible for zoonoses. Excessive use of conventional acaricides has resulted in the onset of drug resistance by these parasites, thus the need to use alternative methods for their control. This study evaluated the acaricidal activities of Chrysopogon zizanioides (vetiver) essential oils containing different zizanoic and khuzimol (high and low acidity) acid concentrations on Amblyomma cajennense and Rhipicephalus microplus (Acari: Ixodidae). To this aims, toxicity tests of different concentrations of examined essential oils were conducted on adult females and larval stages. Results showed that the essential oils of C. zizanioides with high and low acidity reduced oviposition of females, eggs hatch and larval survival, being more effective than some commercial products widely used to control these ectoparasites. These results indicate that the C. zizanoides essential oils are promising candidates as acaricidal agents and represent also an add value to vetiver oil with high acidity, which is commercially undervalued in the cosmetic industry.
Alternative control of Aedes aegypti resistant to pyrethroids: lethal and sublethal effects of monoterpenes bioinsecticides
(Pest Management Science, 2017-11-21) Silva, Indira M. A.; Martins, Gustavo F.; Melo, Carlisson R.; Santana, Alisson S.; Faro, Ruan R. N.; Blank, Arie F.; Alves, Péricles B.; Picanço, Marcelo C.; Cristaldo, Paulo F.; Araújo, Ana Paula A.; Bacci, Leandro
The mosquito Aedes aegypti is intensely controlled because it is vector of viruses that cause innumerous diseases, especially in tropical regions. Due to the indiscriminate use of insecticides, populations from different regions have been resistant to pyrethroids. Here, we analyzed the lethal and sublethal effects of essential oil of Aristolochia trilobata and its major compounds on A. aegypti from susceptible and pyrethroid resistant populations. Our results showed that the toxicity and behavioral changes to different compounds are dependent of the stage of the insect life cycle. The monoterpene ρ-cymene caused high mortality in both larvae and adult females of A. aegypti, including those from the pyrethroid resistant population. The monoterpenes limonene and linalool caused a sublethal effect in the larvae triggering changes in the swimming pattern. This study highlights the potential of the essential oil of A. trilobata, ρ-cymene and limonene to the control of A. aegypti and reveals the importance of analyzing the sublethal effects for the population dynamics of the A. aegypti mosquito.
Control failure likelihood and spatial dependence of insecticide resistance in the tomato pinworm, Tuta absoluta
(Pest Management Science, 2011-03-10) Silva, Gerson A.; Picanço, Marcelo C.; Bacci, Leandro; Crespo, André Luiz B.; Rosado, Jander F.; Guedes, Raul Narciso C.
Insecticide resistance is a likely cause of field control failures of Tuta absoluta, but the subject has been little studied. Therefore, resistance to ten insecticides was surveyed in seven representative field populations of this species. The likelihood of control failures was assessed, as well as weather influence and the spatial dependence of insecticide resistance. No resistance or only low resistance levels were observed for pyrethroids (bifenthrin and permethrin), abamectin, spinosad, Bacillus thuringiensis and the mixture deltamethrin + triazophos (<12.5-fold). In contrast, indoxacarb exhibited moderate levels of resistance (up to 27.5-fold), and chitin synthesis inhibitors exhibited moderate to high levels of resistance (up to 222.3-fold). Evidence of control failures was obtained for bifenthrin, permethrin, diflubenzuron, teflubenzuron, triflumuron and B. thuringiensis. Weather conditions favour resistance to some insecticides, and spatial dependence was observed only for bifenthrin and permethrin. Insecticide resistance in field populations of the tomato pinworm prevails for the insecticides nowadays most frequently used against them – the chitin synthesis inhibitors (diflubenzuron, triflumuron and teflubenzuron). Local selection favoured by weather conditions and dispersal seem important for pyrethroid resistance evolution among Brazilian populations of T. absoluta and should be considered in designing pest management programmes.
Critical yield components and key loss factors of tropical cucumber crops
(Crop Protection, 2006-10) Bacci, Leandro; Picanço, Marcelo Coutinho; Gonring, Alfredo Henrique Rocha; Guedes, Raul Narciso; Crespo, André Luiz Barreto
The critical components and the key factors of yield losses in autumn–winter and spring–summer cucumber crops were determined and quantified in Viçosa county, State of Minas Gerais, Brazil, in areas cultivated with gynoecium hybrids of the groups Aodai (Sprint 440 II) and “Caipira” (Vlasstar). The data were used to build crop life tables. The overall losses in the autumn–winter and spring–summer cultivations were of 53.5 and 66.6 ton ha−1, representing 76.3% and 59.2% of the overall crop yield potential. A critical component of yield loss was flower abortion in both cultivation periods. Fruit loss in the autumn–winter cultivation period was due to deficient pollination and production of non-marketable fruit size, and fruit damage caused by Diaphania spp. (Lepidoptera: Pyralidae), factors that also affected losses in the spring–summer cultivation period, followed by the physiological disturbance caused by nitrogen deficiency.
Eficiência e seletividade de inseticidas para o manejo de mosca branca e inimigos naturais em melancia
(Revista Ceres, 2007-02) Bacci, Leandro; Pereira, Eliseu José Guedes; Crespo, André Luiz Barreto; Picanço, Marcelo Coutinho; Coutinho, Darley Cabral; Sena, Maria Elisa de
Este trabalho teve por objetivo estudar a toxicidade de inseticidas ao biótipo B da mosca branca Bemisia tabaci (Homoptera: Aleyrodidae) e a seletividade ao parasitóide Encarsia sp. (Hymenoptera: Aphelinidae) e ao predador Lasiochilus sp. (Heteroptera: Anthocoridae) em melancia. Inicialmente testou-se a toxicidade de duas dosagens dos inseticidas abamectina 18 CE, carbaril 850 PM, cartape 500 PM, clorpirifós 480 CE, deltametrina 25 CE, etiom 500 CE, fenitrotiom 500 CE, malatiom 500 CE e triclorfom 500 CE a B. tabaci. Posteriormente, realizou-se um bioensaio para testar a toxicidade, tolerância e seletividade de abamectina, cartape, etiom e fenitrotiom a Encarsia sp. e Lasiochilus sp. Os inseticidas foram empregados em concentrações que correspondem a 100% (dose) e 50% (subdose) da dosagem utilizada para o controle da mosca branca. Cartape e abamectina foram eficientes no controle desta praga, com mortalidades superiores a 80%. A mortalidade causada por cartape manteve-se elevada quando se utilizou a subdose. Já a alta mortalidade causada por abamectina decresceu quando se utilizou a metade da dose. O predador Lasiochilus sp. foi mais tolerante a dose e subdose de abamectina e a subdose de cartape do que parasitóide Encarsia sp. Abamectina foi seletivo em favor de Lasiochilus sp. nas duas dosagens utilizadas. Já cartape apresentou seletividade a este predador somente na subdose. Estes resultados irão auxiliar o manejo da mosca branca e de seus inimigos naturais na cultura da melancia.
Essential oil of Lippia sidoides and its major compound thymol: toxicity and walking response of populations of Sitophilus zeamais (Coleoptera: Curculionidae)
(Crop Protection, 2018-10) Santos, Abraão A.; Oliveira, Alexandre P.; Santana, Alisson S.; Lima, Ana Paula S.; Melo, Carlisson R.; Sampaio, Taís S.; Blank, Arie F.; Araújo, Ana Paula A.; Cristaldo, Paulo F.; Bacci, Leandro; Santana, Emile D. R.
The maize weevil, Sitophilus zeamais (Motschulsky) (Coleoptera: Curculionidae), is the main pest of stored grains across tropical regions. An alternative strategy to the use of synthetic insecticides for the management of S. zeamais is the development of botanical insecticides based in the essential oils (EOs) from aromatic plants. In the present study, we evaluated the lethal and sublethal effects of the EO of Lippia sidoides (Cham.) and its major compounds (thymol and ρ-cymene) on different populations of S. zeamais. For this, we determined toxicity by fumigation of treatments of five populations from different Brazilian regions and assessed the lethal time and walking behavior for the most tolerant and susceptible populations. The lethal concentration required to kill 50% of S. zeamais populations ranged from 35.48 to 118.29 μL L^−1 air for EO of L. sidoides, 65.00–91.23 μL L^−1 air for thymol and 801.24 to 2188,83 μL L^−1 air for ρ-cymene. Population from Jacarezinho was the most tolerant to treatments, while population of Rio Branco was the most susceptible one. The survival of S. zeamais populations was significantly affected by treatments and ρ-cymene showed the faster action on both Jacarezinho and Rio Branco populations (LT50 = 0.3 h). The walking behavior of maize weevil showed that the EO of L. sidoides and thymol present repellent effect, however, ρ-cymene present attractive effect. Therefore, the EO of L. sidoides and its major compound thymol are promising source to develop bioinsecticides for the management of S. zeamais populations with different levels of resistance.
Fatores determinantes do ataque de Tuta absoluta ao tomateiro
(Universidade Federal de Viçosa, 2006-11-27) Bacci, Leandro; Silva, Derly José Henriques da; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4723282Z2; Lúcia, Terezinha Maria Castro Della; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4783306E2; Picanço, Marcelo Coutinho; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4786700U4; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4760232Y8; Guedes, Raul Narciso Carvalho; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4721108T2; Sediyama, Maria Aparecida Nogueira; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4783366Z4
Objetivou-se com esta pesquisa estudar: i) os efeitos da fenologia do tomateiro, dos elementos climáticos, da mortalidade natural e da utilização de inseticidas na variação sazonal de populações de Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) e ii) construir e analisar tabelas de vida ecológicas para T. absoluta em diferentes estações do ano, com o intuito de identificar os estágios críticos e os fatores chave de mortalidade desta praga. A utilização de inseticidas no tomateiro reduziu as injúrias de T. absoluta, mas não o suficiente para manter a praga abaixo do nível de dano econômico durante a época mais favorável ao crescimento populacional. O status de praga foi atingido por este inseto na maior parte do tempo após a frutificação do tomateiro. O período de maior densidade de minas e frutos broqueados em lavouras sem aplicação de inseticidas foi entre a 4ª semana de agosto e a 2ª semana de janeiro. Já em lavouras com aplicação de inseticidas estas densidades foram maiores entre a 4ª semana de setembro e 2ª semana de janeiro. A baixa densidade populacional de T. absoluta durante o verão e o outono foi devida a alta mortalidade natural e aos efeitos diretos e indiretos dos elementos climáticos sobre esta praga. A redução da mortalidade natural e o aumento da velocidade do vento e da temperatura do ar foram as causas proximais dos ciclos sazonais de crescimento das populações. Já o declínio das populações correlacionou-se com o aumento da mortalidade natural e efeito negativo direto e indireto da chuva sobre T. absoluta. A mortalidade natural desta praga foi alta e variável entre os períodos amostrados. De forma geral, estes fatores causaram redução populacional na primavera e no verão e aumento no outono e no inverno. O estádio crítico de mortalidade de T. absoluta mais importante foi o estádio larval, sendo que larvas maiores foram mais vulneráveis aos fatores de mortalidade. Os fatores chave de mortalidade mais importantes na primavera-verão e outono-inverno foram a vespa predadora Protonectrina sylveirae e o parasitóide Bracon sp., respectivamente.
Natural mortality factors of tomato leafminer Tuta absoluta in open-field tomato crops in South America
(Pest Management Science, 2019-03) Silva, Laércio J.; Bacci, Leandro; Silva, Ézio M.; Silva, Gerson A.; Rosado, Jander F.; Samuels, Richard I.; Picanço, Marcelo C.
Little importance has been given to the role of natural mortality factors (biotic and abiotic) in the regulation of tomato leafminer Tuta absoluta (Lepidoptera: Gelechiidae) populations. The present study determined the action of mortality factors on T. absoluta populations infesting cultivated tomato crops. Eighty ecological life tables for T. absoluta in field cultivated tomato plants were constructed and analyzed. Total T. absoluta mortality was 99.08%, with 38.76% mortality during the egg phase, 57.20% in the larva phase and 3.12% in the pupal phase. The main mortality factors during the egg stage were predation, parasitism and egg inviability. In the larval stage, the main mortality factors were predation, parasitism, entomopathogenic agents and physiological disorders. In the pupal stage, the main mortality factor was predation. The larvae of the third and fourth instar were more susceptible to the action of mortality factors and the predatory wasp, Protonectarina sylveirae, was the main insect predator of these larvae.The T. absoluta population is regulated under field conditions by the action of natural enemies of the larvae. The predatory wasp P. sylveirae is very important in the regulation of T. absoluta populations in open‐field tomato crops in Brazil.
Sampling plan for diaphania spp. (Lepidoptera: Pyralidae) and for Hymenopteran parasitoids on cucumber
(Journal Of Economic Entomology, 2006-07-20) Bacci, Leandro; Picanço, Marcelo C.; Moura, Marcelo F.; Lucia, Terezinha M. C. Della; Semeão, Altair A.
The objective of this work was to determine the best technique, sampling unit, and the number of samples to compose a conventional sampling plan for the cucurbit borers, Diaphania spp. (Lepidoptera: Pyralidae), and for hymenopteran parasitoids on cucumber. This research was carried out in 10 commercial cucumber crops fields from July to December 2000 in Tocantins, Minas Gerais State, Brazil (21° 11′ 15″ S; 42° 03′ 45″ W; altitude 363 m). The sampling methods studied were beating on a tray, direct counting of insects on the lower leaf surface, and whole leaf collection. Three sampling units also were studied: leaves from a branch located in the apical, median, or basal third of the canopy. The best sampling systems, which included the best technique and sampling unit, were determined based on the relative variance and the economic precision of the sampling. Once the best sampling systems were established, the numbers of samples to compose the conventional sampling plans were determined. The more suitable sampling system for the larvae of Diaphania spp. in cucumber plants was beating a leaf of the median third of the canopy on a plastic tray. One leaf must be sampled for every 50 plants in a crop. The more suitable sampling system for hymenopteran parasitoids in cucumber plants was to directly count the adults on one leaf of the median third of the canopy. One leaf must be sampled for every 74 plants in a crop.
Seasonal variation in natural mortality factors of Tuta absoluta (Lepidoptera: Gelechiidae) in open- ield tomato cultivation
(Journal of Applied Entomology, 2019-02) Silva, Ézio Marques da; Bacci, Leandro; Martins, Júlio Cláudio; Cláudio, Júlio; Campos, Mateus Ribeiro de; Picanço, Marcelo Coutinho
The seasonal variation in natural mortality of phytophagous insects is determined by the relative importance of biotic and abiotic factors in agroecosystems. Knowledge regarding these factors throughout the year represents a key concern for IPM programmes. Seasonal population fluctuations of tomato pinworm, Tuta absoluta, led to an investigation of its natural mortality factors during the rainy season when the population level is low and during the dry season when population peaks occur. The aim of this study was to verify the seasonal variation in T. absoluta mortality factors in tomato crops. Immature stages of T. absoluta were obtained from laboratory rearing in the laboratory. These were taken to the field and monitored over two years. The mortality causes for each stage of insect development from egg to adult were assessed daily. Multiple biotic and abiotic mortality factors affected the immature T. absoluta stages such as rainfall, physiological disturbances, diseases, parasitoids and predators. The key T. absoluta mortality factor during summer–spring was predation. In addition, larvae predation correlated positively with temperature, wind velocity, photoperiod and rainfall. Nevertheless, during winter–fall, the key mortality factor was parasitism. Therefore, the critical stage for mortality was 3rd-and 4thinstar larvae, being more vulnerable to natural control factors. Finally, the results showed the importance of vertical and horizontal action on natural mortality factors.
Seletividade de oito inseticidas a predadores de lagartas em citros
(Pesquisa Agropecuária Brasileira, 2002-02) Galvan, Tederson Luiz; Picanço, Marcelo Coutinho; Bacci, Leandro; Pereira, Eliseu José Guedes; Crespo, André Luiz Barreto
O objetivo deste trabalho foi avaliar a seletividade dos inseticidas abamectina, acefato, carbaril, deltametrina, fenitrotiom, fenpropatrina, paratiom metílico e triclorfom aos predadores Brachygastra lecheguana (Latreille), Protonectarina sylveirae (Saussure) e Protopolybia exigua (Saussure) (Hymenoptera: Vespidae) em concentrações que corresponderam a 50% e 100% da dose recomendada para o controle de lagartas em citros. Os inseticidas estudados não foram seletivos em favor do predador P. sylveirae. Fenitrotiom, fenpropatrina, paratiom metílico e triclorfom não foram seletivos em favor dos predadores B. lecheguana e P. exigua. Abamectina, acefato e carbaril foram medianamente seletivos em favor de P. exigua, o mesmo foi verificado com abamectina e carbaril em favor de B. lecheguana. Acefato foi seletivo em favor de B. lecheguana e deltametrina em favor de P. exigua. As altas mortalidades causadas por deltametrina a P. sylveirae, triclorfom a B. lecheguana e acefato a P. exigua decresceram quando aplicados em subdose. B. lecheguana foi o predador mais tolerante à dose de acefato, seguido por P. exigua e P. sylveirae. O predador P. exigua foi mais tolerante à dose de deltametrina que B. lecheguana e P. sylveirae. As três espécies de predadores foram altamente suscetíveis às doses e subdoses de fenitrotiom, fenpropatrina e paratiom metílico, e à dose de triclorfom.
Seletividade fisiológica de inseticidas a Vespidae predadores de Ascia monuste orseis
(Pesquisa Agropecuária Brasileira, 2002-03) Crespo, André Luiz Barreto; Picanço, Marcelo Coutinho; Bacci, Leandro; Pereira, Eliseu José Guedes; Gonring, Alfredo Henrique Rocha
Este trabalho objetivou estudar a seletividade dos inseticidas carbaril, deltametrina, paratiom metílico, permetrina e triclorfom em relação a Ascia monuste orseis (Godart) (Lepidoptera: Pieridae) e a seus predadores Brachygastra lecheguana Latreille e Protonectarina sylveirae (Saussure) (Hymenoptera: Vespidae). Por meio de curvas de concentração-mortalidade e das concentrações letais para 90% da população (CL90), calcularam-se os índices de seletividade diferencial (ISD90), de toxicidade relativa, e de tolerância relativa (ITRe90). O paratiom metílico e triclorfom apresentaram seletividade em favor de B. lecheguana (ISD90 = 2,83 e 1,75) e P. sylveirae (ISD90 = 2,95 e 3,59) em relação a A. monuste orseis. Deltametrina e permetrina apresentaram seletividade em favor de P. sylveirae (ISD90 = 1,98 e 2,70) em relação a A. monuste orseis, mas não apresentaram seletividade em favor de B. lecheguana (ISD90 = 0,21 e 0,64). B. lecheguana foi menos tolerante a deltametrina, permetrina e triclorfom do que P. sylveirae (ITRe90 = 9,36, 4,23 e 2,05), e mais tolerante ao carbaril (ITRe90 = 0,14). Os predadores apresentaram tolerância semelhante ao paratiom metílico (ITRe90 = 1,04). As curvas de concentração- mortalidade do carbaril, permetrina e triclorfom em ambos os predadores, de deltametrina em B. lecheguana, e de paratiom metílico em P. sylveirae, apresentaram maiores inclinações do que as curvas em A. monuste orseis.
Seletividade fisiológica de inseticidas aos inimigos naturais de Plutella xylostella (L.) (Lepidoptera: Plutellidae) em brássicas
(Ciência e Agrotecnologia, 2009) Picanço, Marcelo Coutinho; Silva, Ézio Marques da; Martins, Júlio Cláudio; Chediak, Mateus; Sena, Maria Elisa; Bacci, Leandro
A conservação de inimigos naturais é um componente fundamental no manejo integrado de pragas. Neste trabalho, estudou-se a seletividade de sete inseticidas usados no manejo de Plutella xylostella (L.) (Lepidoptera: Plutellidae) ao parasitóide Oomyzus sokolowskii (Kurdjumov) (Hymenoptera: Eulophidae) e aos predadores Discodon sp. (Coleoptera: Cantharidae) e Lasiochilus sp. (Hemiptera: Anthocoridae). Os organofosforados metamidofós e paratiom metílico e o carbamato carbaril foram altamente tóxicos aos três inimigos naturais estudados. Dimetoato apresentou seletividade em favor do Discodon sp., na dose e subdose. O inseticida acefato apresentou alto impacto ao Discodon sp., no momento da aplicação e seu efeito foi reduzido com a metade da concentração do princípio ativo. Deltametrina apresentou seletividade à O. sokolowskii nas duas dosagens. Já permetrina foi seletiva a Lasiochilus sp., somente na subdose. Discodon sp. foi mais tolerante à dose e subdose do dimetoato e à subdose do acefato do que O. sokolowskii e Lasiochilus sp. O predador Lasiochilus sp. foi mais tolerante à dose e subdose da permetrina do que O. sokolowskii e Discodon sp. O parasitóide O. sokolowskii foi mais tolerante à dose e subdose da deltametrina do que Lasiochilus sp. e Discodon sp. Os resultados desta pesquisa foram obtidos em condições de exposição extrema, portanto indicam que os inseticidas seletivos possivelmente não serão prejudiciais aos inimigos naturais, em condições de campo.
Sub-lethal effects of essential oil of Lippia sidoides on drywood termite Cryptotermes brevis (Blattodea: Termitoidea)
(Ecotoxicology and Environmental Safety, 2017-07-24) Santos, Abraão Almeida; Oliveira, Bruna Maria Santos de; Melo, Carlisson Ramos; Lima, Ana Paula Santana; Santana, Emile Dayara Rabelo; Blank, Arie Fitzgerald; Picanço, Marcelo Coutinho; Araújo, Ana Paula Albano; Cristaldo, Paulo Fellipe; Bacci, Leandro
The drywood termite Cryptotermes brevis (Walker, 1853) (Kalotermitidae) is one of the most important wood structural pest in the world. Substances from the secondary metabolism of plants (e.g., essential oils) have been considered an environmentally safer form of control for urban pests, such as termites. In the present study, we analyzed the lethal and sub-lethal effects of essential oil of Lippia sidoides and its major components on C. brevis pseudergates in two routes of exposure (contact and fumigation). The essential oil of L. sidoides and thymol were more toxic to C. brevis pseudergates when applied by contact (LD50 = 9.33 and 8.20 µg mg−1, respectively) and by fumigation (LC50 = 9.10 and 23.6 µL L−1, respectively). In general, treatments changed the individual and collective behaviors of C. brevis pseudergates, as well as the displacement and walking speed. The essential oil of L. sidoides and its major components showed a high potential to control C. brevis pseudergates, due to the bioactivity in the two routes of exposure and the sub-lethal effects on the behavior and walking, important activities for the cohesion of C. brevis colonies.