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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352
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Item Plant Extracts as an Alternative to Control Leucoptera coffeella (Guérin-Mèneville) (Lepidoptera: Lyonetiidae)(Sociedade Entomológica do Brasil, 2011-03-14) Alves, DS; Oliveira, DF; Carvalho, GA; Santos Jr, HM dos; Carvalho, DA; Santos, MAI; Carvalho, HWP deWe evaluated the effects of crude extracts from the plantain Plantago lanceolata and the bitter gourd Momordica charantia on the oviposition preference and development of the coffee leaf miner Leucoptera coffeella Guérin-Mèneville & Perrottet under laboratory and/or greenhouse conditions. The ovicidal effects of these extracts were also studied in a greenhouse. Plantago lanceolata and M. charantia extracts also underwent fractionation directed by oviposition tests with the coffee leaf miner. The extracts of both plants reduced L. coffeella oviposition and egg hatching, apparently as a result of action of plant metabolites on the embryo. Adults originating from eggs treated with the extracts exhibited similar survival rates, but a higher female/male ratio. Fecundity was reduced for females obtained from eggs treated with the M. charantia extract. Partial chemical analysis indicated that both extracts produced polar fractions that reduced the oviposition of L. coffeella on coffee leaves under laboratory conditions. The extracts of P. lanceolata and M. charantia have potential for use in the development of new products to control the coffee leaf miner.Item Alternative treatments diminish oviposition and viability of Leucoptera coffeella (Lepidoptera: Lyonetiidae) eggs and larvae on coffee plants(Editora UFLA, 2021) Androcioli, Humberto Godoy; Hoshino, Adriano Thibes; Meneghin, Ana Maria; Ventura, Mauricio Ursi; Guide, Bruna Aparecida; Hata, Fernando Teruhiko; Menezes Junior, Ayres de OliveiraThe effects of alternative treatments on the oviposition and viability of Leucoptera coffeella eggs and larvae were evaluated. Under controlled conditions, coffee sprouts cv. IAPAR-59, eight months old, were sprayed with brown propolis extract (1%), pyroligneous extract with pepper and garlic (PEPG) (2%), silicate clay (2%), kaolin (5%), lime sulfur (2%), neem oil (1%) and kaolin + neem oil (5% + 1%), distilled water and no treatment. In a first no-choice bioassay, coffee sprouts were sprayed before oviposition and kept in cages, where adult insects within three days after emergence were released. Adults remained in the cages for 24 hours. Eggs were then counted. 10 eggs per sprout were preserved to verify larval mortality. The number of eggs when treated with propolis extract, neem oil, kaolin + neem oil and PEPG decreased in the evaluations. Treatments with neem oil caused greater larval hindrance. Eggs laid on leaves were also sprayed with the treatments. Egg viability was reduced by treatments containing neem oil and lime sulfur. Neem oil treatments resulted in slim adult emergence; intermediate viability with lime sulfur and slight hindrance with silicate clay. Finally, treatments were also sprayed on leaves, hosting first or third instar larvae. Neem treatment caused high mortality for 1st and 3rd instar larvae, however, this effect was reduced when mixed with kaolin. Nonetheless, these negative effects disappeared when considering the adult survival ratio. Results indicated that propolis extract, PEPG and neem oil treatments are suitable for reducing egg deposition, neem oil considerably diminished larvae survival and adult emergence.Item Ursolic acid and cis-tiliroside produced by Merremia tomentosa affect oviposition of Leucoptera coffeella on coffee plants(Sociedade Brasileira de Química, 2018) Santos Júnior, Helvécio M.; Lopes, Karina C.; Alves, Dejane S.; Carvalho, Geraldo A.; Oliveira, Denilson F.To contribute to the development of new products to control the coffee leaf miner (Leucoptera coffeella), which is a major pest for coffee plants, this work aimed to select plant species able to produce substances active against this insect and to identify the active substances in the selected plant and their protein targets in the insect. Among the extracts of nineteen plant species, only that from leaves of Merremia tomentosa (Choisy) Hall. f. (Convolvulaceae) reduced the oviposition of L. coffeella on leaves of coffee plants. This extract was submitted to successive fractionation steps to achieve the isolation and identification of two active substances, ursolic acid (UA) and cis-tiliroside (CT). An in silico study showed that UA inhibits glycogen phosphorylases (GP) by binding to their allosteric site, while CT probably inhibits xanthine dehydrogenases (XT). As both GP and XT appear to be essential enzymes for insects, these results suggest that, during evolution, L. coffeella learned to identify plants producing inhibitors of these enzymes to avoid oviposition on such plants. Thus, both UA and CT have potential to be used as lead compounds in the development of new products for the control of the coffee leaf miner.Item Age and time related pheromone production in coffee leafminer Leucoptera coffeella Guérin-Méneville (Lepidoptera: Lyonetiidae)(Sociedade Brasileira de Química, 2008) Lima, Eraldo R.; Vilea, Evaldo F.; Lucia, Terezinha M. C. Della; Ataíde, Lívia M. S.This study was undertaken to access the pattern of sex pheromone production in glands of virgin females of Leucoptera coffeella as an indirect measure of the calling behavior. The major compound, 5,9-dimethylpentadecane (1) was extracted from pheromone glands of virgin females to be used in two experiments. The first one investigated the effect of the pheromone production time by females (extracts of 10 females with age of two days were carried out at 2-hour intervals). The other experiment evaluated the effect of female age on pheromone production (10 females with age ranged from 1 to 5 days after emergence class were used). Hexane extracts were made with 5 ng µL-1 of 5,9-dimethylheptadecane (2) as internal standard and analyzed by GC. Females had the highest amount of pheromone at the last four hours in the dark and the two first hours in the light period. One-day old females produced the highest amount of pheromone in the glands.Item Assessing potential plants extracts to reduce Leucoptera coffeella (lepidoptera: Lyonetiidae) attack in coffee(Editora UFLA, 2020) Fanela, Thiago Luis Martins; Baldin, Edson Luiz Lopes; Bentivenha, José Paulo Franco; Santana, Alisson da SilvaLeucoptera coffeella (Guérin-Méneville) (Lepidoptera: Lyonetiidae) is one of the major pests of coffee in South America, causing severe defoliation in coffee plants. Chemical control has been widely used for the management of this insect. However, this practice is becoming gradually less efficient due to the selection of coffee leaf miner populations resistant to synthetic insecticides. Plants extracts can be a valuable tool for the management of L. coffeella, due to the potential of plants insecticidal properties of them being compatible with the integrated pest management. This study evaluated the effect of nine botanic aqueous extracts on the oviposition and biology of L. coffeella, under laboratory conditions. The extracts of Toona ciliata, Trichilia casaretti and Trichilia pallida decreased the oviposition rate of L. coffeella on coffee leaves. Along with Trichilia catigua, Chenopodium ambrosioides and Melia azedarach, these extracts were classified as deterrent to oviposition by a preference index and the C. ambrosioides, T. casaretti and T. ciliata extracts caused high egg mortality of L. coffeella. Extracts of seeds of A. indica and T. pallida negatively affected the development and survival of L. coffeella, and reduced the mined area by larvae. In conclusion, the extracts of A. indica (S), T. pallida, C. ambrosioides, T. casaretti and T. ciliata exhibited high insecticidal activity and might be useful in integrated management programs for L. coffeella.