Rapid method for detecting resistance to a QoI fungicide in Plasmopara viticola populations

Abstract

It is proposed that the nested PCR-RFLP method is a high-speed, sensitive and reliable tool for detecting azoxystrobin-resistant P. viticola populations.

Diversity and fitness of Plasmopara viticola isolates resistant to QoI fungicides

“…Although a biological test (Wong and Wilcox 2000;Genet et al 1997) or molecular tools have been used to quantify the resistance alleles using real-time q-PCR, ARMS PCR or PCR, (Collina et al 2005;Grasso et al 2006;Toffolatti et al 2007;Sirven and Beffa 2003) or to detect resistant haplotypes using the CAPS method, (Corio-Costet et al 2006;Baudoin et al 2008;Furuya et al 2009) little is known about the fitness of QoIresistant isolates. One study suggested that an artificial P. viticola population containing 5% of resistant isolates tended to increase QoI sensitivity (Genet et al 2006).…”

Characterisation of heteroplasmic status at codon 143 of the Botrytis cinerea cytochrome b gene in a semi-quantitative AS-PCR assay

“…QoI fungicides are highly selective and site‐specific fungicides that inhibit mitochondrial respiration by binding to the ubiquinol‐oxidising pocket, called the Qo site, of the cytochrome bc 1 enzyme complex . A single amino acid substitution at residue 143 (G143A) of cytochrome b of some plant pathogens confers resistance to QoI fungicides . The G143A mutation has been reported in B. cinerea.…”

“…In Japanese vineyards, azoxystrobin, a QoI fungicide, is frequently applied to prevent grape downy mildew caused by Plasmopara viticola . However, the resistance of certain P. viticola populations to azoxystrobin emerged in 2008 and is spreading throughout Japan . Under these circumstances, QoI‐fungicide‐resistant B. cinerea from Japanese vineyards was isolated.…”

Phenotypic Analyses of Fenhexamid Resistant Botrytis cinerea Mutants

“…In Japan, although fenhexamid was registered in 2000, it is not widely used and thus, the existence of fenhexamid resistance in B. cinerea has not been reported in Japan. Molecular-based techniques have been developed to rapidly detect the sensitivity of fungi to several fungicides by taking advantage of point mutations in target genes (Oshima et al 2002;Paplomatas et al 2004;Banno et al 2008, Furuya et al 2009Saito et al 2009). A rapid method for the detection of fungicide resistance is necessary for viticulturists to better understand the incidence of resistance in B. cinerea populations in their vineyards.…”