| Registro completo |
| Provedor de dados: |
Ciência Rural
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| País: |
Brazil
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| Título: |
Glomerella leaf spot in apple: validation of proposed diagrammatic scale and efficiency of fungicides
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| Autores: |
Kowata,Lígia Sayko
Strapasson,Michele
Challiol,Márcio Alberto
May-De Mio,Louise Larissa
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| Data: |
2010-07-01
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| Ano: |
2010
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| Palavras-chave: |
Malus domestica
Colletotrichum spp
Chemical control
Disease quantification
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| Resumo: |
A diagrammatic scale to assess Glomerella leaf spot severity (Colletotrichum spp) was developed and validated during the tryout of a fungicide efficiency experiment in the field. Apple leaves were collected for determination of minimum and maximum severity limits; intermediate levels were obtained according to "Weber-Fechner's stimulus-response law". Scale validation was performed by four raters, which estimated the severity in 100 leaves; with and without the use of the scale. An experiment was carried out in a commercial orchard in randomized blocks with 10 plants. The treatments and dosages (g 100 L-1 of water) used were: cyprodinil (15); pyrimethanil (30, 37.5, 45); propineb (140) e mancozeb (160) + tebuconazole (12.50), and a control (no spray). The incidence and severity in leaves; number of fruits, weight and incidence in fruit (harvest) and defoliation (after harvest) were evaluated. The proposed scale showed the levels of 0.08; 0.28; 0.99; 3.45; 11.23 and 30.93%. The scale was adequate for severity assessment; R2 changed from 0.68 to 0.96 with the use of the scale. Pyrimethanil treatments did not control the disease. The incidence on fruit was 30 and on leaves 63%. The incidence was reduced in 35.6% (propineb) and 33.7% (mancozeb + tebuconazole) related to the control, these treatments were efficient to control the disease. The defoliation was 44 % in the control against 9.6 and 2.5% to propineb and mancozeb + tebuconazole.
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| Tipo: |
Info:eu-repo/semantics/article
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| Idioma: |
Inglês
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| Identificador: |
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782010000700004
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| Editor: |
Universidade Federal de Santa Maria
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| Relação: |
10.1590/S0103-84782010000700004
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| Formato: |
text/html
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| Fonte: |
Ciência Rural v.40 n.7 2010
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| Direitos: |
info:eu-repo/semantics/openAccess
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