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Bento Gonçalves, Brazil

The oriental fruit moth Grapholita molesta is one of the main pests of apple and peach trees. In this study, the mortality caused by insecticides when applied on different stages of development of G. molesta and about fruits and tops of apple and peach trees was evaluated. The insecticides acetamiprid (8g 100L -1), phosmet (100 g 100L -1), spinetoram (3.75 g 100L -1) and novalurom (4.0 g 100L -1) reduced hatching in levels above 80%, regardless of whether the application is performed before or after oviposition. The etofenprox (15 g 100L -1) was the most effective when applied after oviposition. In apple and peach tops, the insecticides acetamiprid, chlorantraniliprole (4.9 g 100 L-1), etofenproxi, phosmet, novaluron and spinetoram caused mortality of larvae over 90%. In apple fruits, the insecticides acetamiprid, chlorantraniliprole, etofenprox, phosmet, and spinetoram, caused 100, 79, 76, 97 and 100% mortality, respectively, whereas in peach fruits this control was over 85%. The insecticide novaluron caused lower mortality of larvaes when applied on fruits, compared to the application on tops. In adults, only the insecticides etofenprox and phosmet were toxic both to females (59% and 39%) and males (79% and 80%), while spinetoram was effective only in males (78%). It is concluded that insecticides etofenprox, phosmet and spinetoram were efficient in the control of G. molesta in all stages of development. © 2014, Sociedade Brasileira de Fruticultura. All rights reserved. Source

E Silva O.A.B.N.,University of Sao Paulo | Botton M.,Pesquisador Embrapa Uva e Vinho | Garcia M.S.,FAEM UFPel | da Silva A.,FAEM UFPel
Revista Brasileira de Fruticultura | Year: 2011

The objective of this study were to evaluate the effect of insecticides insect growth regulators (IGR's) on eggs, larvae and adults of G. molesta, in the laboratory. The evaluated insecticides were Lufenuron and Novaluron (4.0g of a.i. 100L-1), Methoxyfenozide and Tebufenozide (9.6g of a.i. 100L-1) and control (distilled water). In application before oviposition, only Methoxyfenozide caused significant mortality of eggs (26.3%) compared to control. The application of insecticides on eggs of different ages (24, 48 and 72 hours) showed variations in mortality of the species regarding the insecticide and time of embryonic development. Only Methoxyfenozide and Novaluron reduced the viability of larvae that emerged from treated eggs, with a maximum of 35.9% and 39.5 of larval viability when applied on eggs of 48-72 hours, respectively. The treatment of apple fruit with insecticides caused significant mortality of larvae, but no differences were observed among insecticides, both for small larvae (average efficiency of 47.2%) and for 3rd -4th instar larvae (averaging 45.3%). Lufenuron reduced its efficacy on 3rd-4th instar larvae. The ingestion of Lufenuron, Methoxyfenozide, Novaluron and Tebufenozide by adults of G. molesta reduced fecundity and fertility, however the adult longevity was only negatively affected by the ingestion of Methoxyfenozide and Tebufenozide. Source

Chavarria G.,University Of Passo Fundo | dos Santos H.P.,Pesquisador Embrapa Uva e Vinho | Mauro C.Z.,Pesquisador Embrapa Uva e Vinho | Marodin G.A.B.,Federal University of Rio Grande do Sul | Zorzan C.,Enologo Bolsista DTI Embrapa Uva e Vinho
Revista Brasileira de Fruticultura | Year: 2011

The aim of this study was to evaluate plastic overhead covering (POC) influence on must and wine of Moscato Giallo cultivar. In two harvests the 2006 and 2007 vintages an experiment was carry out in a completely randomized design. It was performed in a vineyard covered with an impermeable plastic cloth and without covering as control. From each vineyard, three microvinification (20 L) were elaborated. Physico-chemical analysis of musts (oBrix, reduce sugar content, density, total acidity, tartaric acid, malic acid e pH) and wines (density, alcohol degree, acidity, volatile acidity, pH, dry extract, reduce sugar content, ashes, 420 index, volatile compounds and minerals) were analyzed. According to results POC (raffia type with 160 μm) grapes showed more yield must. However due to delay maturation showed lower sugar concentration. Wine produced with POC grapes had lower alcohol graduation. Another hand, the better sanity of grapes resulted in lower tenors of ethyl acetate and volatile acidity. POC system demands delay in harvest to achieve the same sugar concentration and alcohol graduation compared to grapes from open sky. Source

Conceicao M.A.F.,Pesquisador Embrapa Uva e Vinho | Tonietto J.,Pesquisador Embrapa Uva e Vinho | Fialho F.B.,Pesquisador Embrapa Uva e Vinho
Revista Brasileira de Fruticultura | Year: 2012

The Geoviticulture Multicriteria Climatic Classification System (CCM), used to characterize the climate in grape production regions, is composed by the Heliothermal Index (HI), the Cool Night Index (CI) and the Dryness Index (DI), which is based on the potential soil water balance. The calculation of DI values requires precipitation and evapotranspiration potential (ETP) data, estimated using the standard Penman-Monteith method. However, not all grape regions have the climatic variables required to use this ETP method. Therefore, it is important to use other methods to estimate ETP based only on air temperature available data, such as the Hargreaves ETP method. The present study compared the Drought Index values calculated using the Penman-Monteith and the Hargreaves methods for different grape growing regions of the world. Climate data from 83 meteorological stations were used, representing grapevine regions located in 18 countries. The Hargreaves equation achieved a very good performance and can be used in the CCM system in places where there are insufficient data for the Penman-Monteith method. Source

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