An International System of Nomenclature forPuccinia graminisf. sp.tritici

Abstract

A new set of international differential hosts for characterizing the virulence of cultures of Puccinia graminis f. sp. tritici including the host resistance genes Sr5, 6, 7b, 8a, 9b, 9e, 99, I I, I 7, 2 l, 30, and 36 is proposed. Additionally, a resistant series that consists ofhost genes 5r13,22,24,25, 26,2'7. 31,32, 33, and 37 that have generally been resistant worldwide is recommended for evaluating bulk collections or composites of individual cultures. The use ofadditional differential hosts oflocal interest, especially those related to national breeding programs, is encouraged. Races are to be designated by a three-letter code (Pgt-code) followed by a hyphen and a listing of those host genes in the 'resistant' set on which the race was virulent. Data on local supplemental series should be separated from the Pgt-code by a slash. A central type-culture collection is proposed and will be maintained at the Cereal Rust Laboratory at St. Paul, MN, for use in breeding and research programs. Type-cultures will be evaluated against the resistance conferred by the known single genes.

Inheritance and mapping of stem rust resistance of wheat line PI 410966

“…For the F 6:7 Pgt test with race TTKSK, lines with infection type (IT) ranging from 0-0;, ;, ;1, ;1 + , and ;13 -were classified as resistant, and lines with IT 3 to 4 were classified as susceptible (Stakman et al 1962;Roelfs and Martens 1988). IT of PI 410966 was ;1 to ;13 -, and OK3040 had an IT of 4.…”

“…This race was classified as TTKSK based on the North American nomenclature system (Roelfs and Martens 1988;Wanyera et al 2006;Jin et al 2008). This new race poses a serious threat to East Africa and to the Middle East since a majority of the wheat cultivars grown in these regions are susceptible to race TTKSK (Reynolds and Borlaug 2006).…”

Resistance of Tangmai 4 wheat to powdery mildew, stem rust, leaf rust, and stripe rust and its chromosome composition

“…Plants were identified susceptible when powdery mildew colonies covered at least 5% of the first three leaves, or resistant when no symptoms or colonies developed on less than 5% of the leaves. Sr6,Sr7b,Sr8,Sr8a,Sr9b,Sr9e,Sr9g,Sr11,Sr17,Sr30 and Sr36, as determined using differential sets (Roelfs and Martens 1988). Tangmai 4 and the check cultivars were arranged in a randomized complete block design with four replications and six plants each plot.…”

Development of a Specific SCAR Marker to Race 21C3CTH of Puccinia graminis f. sp. tritici in China

“…Owing to extensive race and virulence surveillance of Pgt populations, the disease has been successfully controlled in the past few decades, mainly through the breeding and release of resistant cultivars (Li and Zeng, 2002;Raloff, 2005;Singh et al, 2011, Pardey et al, 2013. Race identification, which began approximately 100 years ago, was traditionally performed only on wheat hosts of differential genotypes, including Stakman's set (Stakman and Premeisel, 1917) or Stakman's set plus supplementary hosts, or in recent years 5 sets of different known stem rust resistance gene (Sr) line hosts (Roelfs and Martens, 1988;Jin et al, 2009;Cao and Chen, 2010). However, these race identification protocols are somewhat time consuming, laborious, expensive and require specific environmental conditions.…”