Effectiveness of acibenzolar‐S‐methyl, fungicides and antibiotics for the control of brown eye spot, bacterial blight, brown leaf spot and coffee rust in coffee

Abstract

This study was carried out to evaluate the potential of acibenzolar‐S‐methyl (ASM), combined or not combined with fungicides and antibiotics for the control of brown eye spot (Cercospora coffeicola) and bacterial blight (Pseudomonas syringae pv. garcae) in coffee seedlings, and ASM combined with conventional fungicide application schedules for the control of coffee rust (Hemileia vastatrix) and brown leaf spot (Phoma costarricencis) under field conditions in two coffee crops in the State of São Paulo, Brazil. ASM protected coffee seedlings against C. coffeicola when applied at the rates of 2.5 and 5 g of active ingredient per hectolitre of water (g a.i. hL−1), providing 34–55% of disease control, and against bacterial blight, when applied at the rates of 2.5, 10 and 20 g a.i. hL−1, with 38–57% of disease control. Tebuconazole (100 g a.i. hL−1) and azoxystrobin (10 g a.i. hL−1) showed the best results for brown eye spot control. Oxytetracycline + streptomycin, kasugamycin hydrochloride, oxytetracycline + metallic copper, copper oxychloride and mancozeb + copper oxychloride also controlled bacterial blight in levels similar to those shown by ASM. In the field experiments, all fungicide application schedules tested, cyproconazole (December, February, April), epoxiconazole (December, March), tetraconazole (December, February, April), cyproconazole (December, February) and azoxystrobin (January, March) were effective for coffee rust control and provided partial control of brown leaf spot. The results also showed that for all experiments, there was no synergistic effect of the combination of ASM with azoxystrobin, cyproconazole or cupric fungicides.

Diagrammatic Scale for Assessment of Bacterial Blight in Coffee Leaves

“…Thus, Patrício et al. () emphasized that a scale developed and validated to estimate the percentage of DLA (severity) should be used in future studies.…”

Proteção do cafeeiro contra cercosporiose por acibenzolar-S-metil e proteína harpina

“…), com um intervalo de aproximadamente 30 dias entre a primeira e a segunda avaliação. A severidade da doença foi determinada pela contagem do número total de lesões por folha por planta (Patrício et al, 2008).…”

“…A aplicação prévia de ASM em plantas resulta na ativação de diversos mecanismos de defesa, o que confere proteção sistêmica contra diferentes patógenos em várias culturas como o feijoeiro, cacaueiro e cafeeiro (Guzzo et al, 2001;Resende et al, 2002;Iriti & Faoro, 2003;Patrício et al, 2008;Nojosa et al, 2009). Diferentes agentes bióticos apresentam, também, efeitos significativos como ativadores de mecanismos de defesa de plantas contra diversas doenças como, por exemplo, a proteína harpina isolada de Erwinia amylovora (Capdeville et al, 2002).…”

Effect of Bayfolan® copper on the control of Pseudomonas syringae pv. garcae in vitro

“…For the chemical control of this bacteriosis, few products are available in the Phytosanitary Pesticide System (AGROFIT, 2019) such as copper oxychloride fungicide and Kasugamycin antibiotic. However, this type of treatment should be performed before the plant is infected, thus acting as a preventive, for greater protection of the plant and lower rates of the disease (PATRÍCIO, 2008).…”