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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352
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Item Insecticide application rate in coffee crop: qualitative and quantitative aspects and efficacy of leaf miner control(Editora UFLA, 2020) Melo, Thiago Lima; Raetano, Carlos Gilberto; Cardoso, Adriana Dias; Moreira, Aldenise Alves; Leite, Suzany Aguiar; Castellani, Maria AparecidaLeaf miner is a key coffee crop pest in Central and South America countries, especially in Brazil, where the insect causes considerable production losses. In the management of this insect pest, insecticide applications at reduced rates are fundamental for improve the operational capacity of the sprayer and the rational use of water. Thus, the aim of this study was to select a application rate that ensures effectiveness of cyantraniliprole, cartape hydrochloride and beta-cypermethrin insecticides in the leaf miner control, good spraying quality with varying application rates and low impact on natural parasitism. The qualitative and quantitative aspects of spraying with the Brilliant Blue marker were evaluated at the following rates: 28.1, 60.5, 80.2 and 180.0 L ha-1 and the efficacy of cyantraniliprole, cartape hydrochloride and beta-cypermethrin insecticides, with doses of the commercial formulations. Pest infestation and parasitism were determined before and after applications. Application rate interferes with qualitative aspects and spray deposition levels. Considering the quality-quantitative aspects and Agronomic Efficacy, rates between 80.2 and 180.0 L ha-1 are the most suitable for the control of this insect. Cyantraniliprole insecticide is effective in controlling L. coffeella up to 45 DAA at rate of 180.0 L ha-1. The impact of cyantraniliprole, cartape hydrochloride and beta-cypermethrin insecticides on L. coffeella natural parasitism varies with application rates and time after application.Item Management of coffee leaf miner: spray volume, efficacy of cartap hydrochloride and impact on parasitism(Editora UFLA, 2019-04) Melo, Thiago Lima; Raetano, Carlos Gilberto; Nery, Moizés Silva; Cardoso, Adriana Dias; Moreira, Aldenise Alves; Leite, Suzany Aguiar; Jesus, Thamires Francisca de; Silva, Wesley Gil Oliveira; Castellani, Maria AparecidaThe leaf miner is a key pest of coffee and the use of insecticides for its control results in high water consumption. The objective in this study was to evaluate the quali-quantitative aspects of reduced spray volumes with and without the addition of adjuvant, the efficacy of the insecticide cartap hydrochloride in the control of the pest and its effects on the parasitism. Two experiments were carried out in coffee plantations in São Desiderio, BA. Initially, solution of Brilliant Blue tracer (0.15% p v -1 ) of the 43, 112, 146 and 309 L ha -1 volumes was sprayed with and without the soybean oil methyl ester adjuvant (0.25 % v v -1 ). Before spraying, water-sensitive cards were fixed to the plants and subsequently used for analyze the droplet spectrum in Gotas 1.0 software. The tracer deposit was determined by spectrophotometry. Posteriorly, the insecticide cartap hydrochloride (0.5 kg a.i. ha -1 ) was applied in the same volumes and types of spray used in the first test. Infestation rates of pest and parasitism were evaluated before and after application of the insecticide. The quali-quantitative aspects of the sprays were affected by the volume of spray applied, by the adjuvant and by the interaction of the factors. The intermediate volumes yielded better spraying quality without the presence of the adjuvante, with higher number and desity of drops. The spraying volume affected the depoisto the Brilliant Blue tracer in a linear and positive form. The efficacy of the insecticide was prolonged with the lowest volume spray and with adjuvant and its impact on parasitism varied with the volume applied and time after application.Item Ocorrência sazonal, predação e parasitismo de Leucoptera coffeella (Guérin-Méneville, 1842) (Lepidoptera: Lyonetiidae) em cafeeiros associados à grevíleas(Editora UFLA, 2014-01) Souza, Tiago Pinho; Castellani, Maria Aparecida; Lemos, Raimunda Nonata Santos de; Maluf, Raquel Pérez; Moreira, Aldenise Alves; Silva, Bruna Santos; Ribeiro, Edenilson BatistaO bicho-mineiro, Leucoptera coffeella, é praga chave do cafeeiro, causando perdas significativas na produção. Objetivou-se, neste trabalho, estudar a ocorrência sazonal do bicho-mineiro e as taxas de infestação, parasitismo e predação natural da praga em cafeeiros arborizados com grevíleas, na região Sudoeste da Bahia, Brasil. O experimento foi composto por cinco campos de observação (tratamentos) e quatro repetições, totalizando 20 parcelas. Os tratamentos foram definidos pelo espaçamento das plantas de grevílea associadas ao cafeeiro Catuaí Vermelho (IAC 144): Tratamento 1 – pleno sol – sem grevílea; Tratamento 2 – 18x18m = 31 grevíleas.ha -1 ; Tratamento 3 – 12x12m = 69 grevíleas.ha -1 ; Tratamento 4 – 6,0x12m =139 grevíleas.ha -1 ; e Tratamento 5 – 6,0x6,0m = 277 grevíleas.ha -1 . As parcelas consistiram de quatro (T4 e T5) e seis plantas de café (T1, T2 e T3), ao redor de uma planta de grevílea. Foram quantificadas as folhas com minas, minas por folha, total de minas, minas predadas e minas parasitadas, de setembro/2011 a junho/2012. Os resultados indicaram que a influência do aumento da densidade de grevíleas na população do bicho-mineiro não é uniforme ao longo do tempo, apresentando-se desfavorável no período de setembro a dezembro de 2011, até densidades na faixa de 180 a 220 grevíleas.ha -1 , a partir das quais o crescimento populacional do inseto é favorecido. No período de fevereiro a junho de 2012, o aumento na densidade de grevíleas atua negativamente na população da praga. A predação apresenta a mesma tendência da infestação do bicho-mineiro em relação à densidade de grevíleas, enquanto que o parasitismo não apresenta um padrão de comportamento em relação àquela variável. A relação entre predação e parasitismo é positiva.