Effect of Treating Apple Trees with Acibenzolar-S-Methyl on Fire Blight and Expression of Pathogenesis-Related Protein Genes

Abstract

Acibenzolar-S-methyl (ASM, Actigard 50 WG), a synthetic inducer of systemic acquired resistance (SAR) and pathogenesis-related (PR) proteins, was evaluated for the control of fire blight on apple trees in the field and for PR protein gene expression in apple seedlings in the greenhouse. Expression of putative genes related to SAR induction was elevated in ASM-treated apple seedlings 2 to 7 days after treatment; levels of PR-1 and PR-8 RNA were increased 10-fold and PR-2 RNA was increased 100-fold in ASM-treated seedlings over levels in untreated seedlings. Spurs and shoots on Jonathan trees sprayed with ASM at 75 mg a.i./liter at pink and at weekly intervals thereafter had significantly less fire blight than untreated trees, both from natural infection and following artificial inoculation with the pathogen. Less fire blight was observed on trees sprayed weekly with ASM than on trees sprayed biweekly. The severity of fire blight on inoculated shoots of Fuji apple decreased with increasing rates of ASM (0 to 300 mg a.i./liter), and ASM combined with streptomycin showed enhanced activity over ASM at 75 mg a.i./liter alone. In general, ASM was not superior to streptomycin for fire blight control, but integrating a weekly schedule of ASM, preferably at 150 mg a.i./liter, with a schedule of streptomycin designed for blossom blight control appears promising for overall improvement in fire blight control.

Effect of Acibenzolar-S-methyl and Rahnella aquatilis (Ra39) on Chitinase and β-1, 3-glucanase Activities and Disease Resistance of Apple Plants

“…For all tested periods after treatment by ASM and Ra39, the disease index reduced greatly than the control plants. These results agree with those reported by Siegrist et al (1997); Maxson-Stein et al (2002); Zeller and Laux (2002); Abo-Elyousr and ElHendawy (2008); who mentioned that ASM could reduce the diseases severity of bacterial diseases under greenhouse and field conditions. Also, our results indicated that Ra39 reduce the diseases severity and this finding are according to Chen et al (2009);Calvo et al (2007).…”

“…(Maxson-Stein et al, 2002;Baysal and Zeller, 2004;AboElyousr et al, 2005;. Results of this study revealed that application of ASM to apple shoots caused the higher chitinase activity than that of Ra39.…”

Abiotic elicitors mediated elicitation of innate immunity in tomato: an ex vivo comparison

“…It further leads to activation of signal transduction pathways, phytoalexin biosynthesis, cell wall strengthening, callose deposition, defense related enzymes synthesis, and the accumulation of pathogenesisrelated (PR) proteins (Van Loon and Van Strien 1999;Thakur and Sohal 2013). Development of resistant crop was achieved by the over expressing of various defense related genes encoding defense enzymes and phenol production (Maxson-Stein et al 2002;Anand et al 2009;Acharya et al 2011a, b;Pal et al 2011). Furthermore, signaling molecule like nitric oxide (NO) beside many of its useful function provide protection of plants in response to abiotic and biotic stressors (Corpas et al 2011;Leterrier et al 2012).…”

Caracterización molecular y desarrollo de métodos de diagnóstico del género Fabavirus Evaluación de BTH como método de control

“…Para el control de enfermedades se han obtenido productos químicos análogos al SA que inducen la SAR tales como, el ácido 2,6 -dicloroisonicotinico y su metil éster, ambos denominados INA y el S-metil benzo[1,2,3]tiadiazol-7-carbotioato (BTH) (Zhu et al, 2002;Pérez et al, 2003;Zhu et al, 2003;Pérez-de-Luque et al, 2004;Serrano et al, 2007;Zhu et al, 2008), que suministra protección frente a diversas enfermedades en una amplia gama de cultivos Maxson-Stein et al, 2002;Agostini et al, 2003) .…”

“…vesicatoria deben realizarse aplicaciones cada 7-10 días (Louws et al, 2001). También se han realizado ensayos en otras solanáceas como tomate y tabaco (Csinos et al, 2001;Perez et al, 2003), leguminosas como haba o soja (Dann & Deverall, 1995;Dann & Deverall, 1996) y frutales como manzanos y perales (Ishii et al, 1999;Maxson-Stein et al, 2002). Sin embargo, como todas las técnicas, existen ventajas y desventajas que deben de ser tenidas en cuenta (Kuc, 2001).…”