Anthocyanins are flavonoid pigments imparting red, blue, or purple pigmentation to fruits, flowers and foliage. These compounds are powerful antioxidants in vitro, and are widely believed to contribute to human health. The fruit of the domestic apple (Malus x domestica) is a popular and important source of nutrients, and is considered one of the top 'functional foods'-those foods that have inherent health-promoting benefits beyond basic nutritional value. The pigmentation of typical red apple fruits results from accumulation of anthocyanin in the skin. However, numerous genotypes of Malus are known that synthesize anthocyanin in additional fruit tissues including the core and cortex (flesh). Red-fleshed apple genotypes are an attractive starting point for development of novel varieties for consumption and nutraceutical use through traditional breeding and biotechnology. However, cultivar development is limited by lack of characterization of the diversity of genetic backgrounds showing this trait. We identified and cataloged red-fleshed apple genotypes from four Malus diversity collections representing over 3,000 accessions including domestic cultivars, wild species, and named hybrids. We found a striking range of flesh color intensity and pattern among accessions, including those carrying the MYB10 R 6 allele conferring ectopic expression of a key transcriptional regulator of anthocyanin biosynthesis. Although MYB10 R 6 was strongly associated with red-fleshed fruit among genotypes, this allele was neither sufficient nor required for this trait in all genotypes. Nearly all red-fleshed accessions tested could be traced back to 'Niedzwetzkyana', a presumed natural form of M. sieversii native to central Asia.

Surveys for phytoplasmas and viruses were conducted during September 2014 and 2015 on highbush blueberry farms in the Région Montérégie, Quebec. Total DNA and RNA were extracted from blueberry bushes showing blueberry stunt (BBS) symptoms and from symptomless blueberry bushes, and utilised as templates for PCR and RT‐PCR assays, respectively. Phytoplasma DNA was amplified with universal phytoplasma primers that target the 16S rRNA, secA and secY genes from 12 out of 40 (30%) plants tested. Based on 16S rRNA, secA and secY gene sequence identity, phylogenetic clustering, actual and in silico RFLP analyses, phytoplasma strains associated with BBS disease in Quebec were identified as ‘Candidatus Phytoplasma asteris’‐related strains, closely related to the BBS Michigan phytoplasma strain (16SrI‐E). The secY gene sequence‐based single nucleotide polymorphism analysis revealed that one of the BBS phytoplasma strains associated with a leaf marginal yellowing is a secY‐I RFLP variant of the subgroup 16SrI‐E. Two viruses were detected in blueberry bushes. The Blueberry Red Ringspot Virus (BRRV) was found in a single infection in the cultivar Bluecrop with no apparent typical BRRV symptoms. The Tobacco Ringspot Virus (TRSV) was found singly infecting blueberry plants and co‐infecting a BBS phytoplasma‐infected blueberry cv. Bluecrop plant. This is the first report of TRSV in the cv. Bluecrop in Quebec. The Quebec BBS phytoplasma strain was identified in the leafhopper Graphocephala fennahi, which suggests that G. fennahi may be a potential vector for the BBS phytoplasma. The BBS disease shows a complex aetiology and epidemiology; therefore, prompt actions must be developed to support focused BBS integrated management strategies.

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Soybean mosaic virus (SMV) can be present wherever soybean is grown, causing yield loss and seed quality deterioration. We have isolated SMV from eight soybean samples collected from fields in Ontario and Quebec, the two major soybean producing provinces in Canada. The coat protein region of these isolates was amplified, sequenced, and compared with 14 published sequences to determine the phylogenetic relationship among them. It was found that all eight isolates were most related to the SMV G2 group identified in the US. Further parsimony analysis of partial SMV sequences suggests that there are at least three SMV genotypes present in Ontario and two in Quebec. Three representative isolates were used for a pathogenicity test. As expected, all of them could infect a susceptible cultivar and a resistant cultivar carrying the resistance gene Rsv3, but could not infect resistant cultivars carrying the resistance genes Rsv1, Rsv1-h, or Rsv4. Résumé : Le virus de la mosaïque du soja (SMV) peut se trouver partout où est cultivé le soya, causant des pertes de rendement ainsi qu'une détérioration de la qualité des semences. Nous avons isolé le SMV de huit échantillons de soja collectés dans des champs situés en Ontario et au Québec, les deux plus importantes provinces productrices de soja au Canada. La région de la protéine de coque de ces isolats a été amplifiée, séquencée et comparée à 14 séquences publiées afin d'en déterminer les relations phylogénétiques. Il s'est avéré que les huit isolats étaient principalement apparentés au groupe G2 du SMV identifié aux États-Unis. Une analyse additionnelle de parcimonie de séquences partielles de SMV suggère qu'il y a au moins trois génotypes de SMV en Ontario et deux au Québec. Trois isolats représentatifs ont été utilisés aux fins d'un test de pathogénicité. Comme on s'y attendait, tous pouvaient infecter un cultivar réceptif et un cultivar résistant porteur du gène de résistance Rsv3, mais ne pouvaient infecter les cultivars résistants porteurs des gènes Rsv1, Rsv1-h ou Rsv4.Mots-clés : virus de la mosaïque du soja, potyvirus, Glycine max, analyse phylogénétique.Viel et al.: soybean mosaic virus / phylogenetic analysis / coat protein 113