A North American System of Nomenclature for Puccinia coronata f. sp. avenae

Abstract

A nomenclature system for designating virulence phenotypes of Puccinia coronata f. sp. avenae, the causal agent of oat crown rust, is proposed. Sixteen single gene oat (Avena sativa) lines, with seedling resistance genes Pc38, 39, 40, 45, 46, 48, 50, 51, 52, 54, 56, 58, 59, 62, 64, and 68, are the primary differentials. The host lines are arranged into groups of four (subset 1 = Pc40, 45, 46, 50; subset 2 = Pc38, 39, 48, 68; subset 3 = Pc51, 52, 58, 59; subset 4 = Pc54, 56, 62, 64). Avirulence and virulence of Puccinia coronata f. sp. avenae isolates on each line are indicated by low and high infection types, respectively. A letter from the 16 consonants B through T is assigned to each of the 16 possible combinations of low and high infection types on the four differentials of each subset. Designations for P. coronata f. sp. avenae virulence phenotypes are indicated by a four-letter code for the virulence combinations on all four subsets, one letter for each subset. Local differential series are separated from the four-letter code by a dash, followed by an additional letter code describing the virulence combinations of the isolates on the local supplemental differentials. When fewer than four differentials are used in the supplemental series, virulence combination on these differentials for each isolate is described by a listing of the Pc gene(s) to which the isolate was virulent, following the four-letter code and a dash. This nomenclature system for P. coronata f. sp. avenae is similar to the nomenclature system in use for P. graminis f. sp. tritici and P. triticina.

Crown rust pathotypes determined on oats in the Czech Republic from 2004 to 2006 and reaction to oat cultivars

“…Infection types from 0 to 2 indicated resistance while types 3 and 4 denoted susceptibility (Figure 1). The four-letter code of pathotype designation was used (Chong et al 2000).…”

“…The basic set of 16 differentials required for pathotype designation according to the nomenclature proposed by Chong et al (2000) was included.…”

Virulência de isolados de Colletotrichum gloeosporioides de populações selvagens de Stylosanthes spp

“…avenae), desenvolvido por Chong et al (2000). Os 12 acessos diferenciadores foram dispostos em três subconjuntos de quatro diferenciadores; para cada subconjunto, existem apenas 16 combinações de tipos infecção alta e baixa, arranjados em um sistema binário.…”

Herança da resistência à ferrugem da folha da aveia (Puccinia coronata f. sp. avenae Fraser & Led.) em genótipos brasileiros de aveia branca

“…Quinze dias após a inoculação dos genótipos, foi efetuada a avaliação dos resultados. A distinção entre alto (virulência) e baixo (avirulência) o tipo de infecção foi realizada com base no critério descrito por CHONG et al (2000). Foi empregada uma escala quantitativa composta de notas variando de 0 a 4 onde: (0) = ausência urédia ou outros sinais macroscópicos de infecção, (;) = presença de reação marcante de hipersensibilidade sem esporulação, (1) = pequena urédia rodeada por clorose ou necrose, (2) = urédia de tamanho variando de pequeno a médio rodeada por clorose, (3) = urédia de tamanho médio em área clorótica e (4) = grande urédia sem clorose ou necrose.…”