(McIntosh, 1978) (Plate 3-29)
Synonym
SrKtal (Berg et al., 1963).
Chromosome Location
2BL (McIntosh, 1978). Sr28 was located 18 cM distal to Sr9 and 33 cM proximal to Sr16.
Low Infection Type
0; to 2=.
Environmental Variability
Low (Roelfs and McVey, 1979).
Origin
Common wheat cv. Kota. Kota was included in the differential set of Stakman et al. (1962).
Pathogenic Variability
Virulence is common in all geographic areas (Luig, 1983). Huerta-Espino (1992) found significant levels of avirulence among cultures from Ethiopia and Nepal; otherwise virulence levels were high.
Reference Stocks
i: Line AD = W2691*5/Kota (McIntosh, 1978).
s: Ceres Sr7b (McIntosh, 1978); Kota Sr7b (McIntosh, 1978).
Source Stocks
None.
A. and B. Seedling leaves of (L to R): Line AD (W2691*5/Kota), Kota, Ceres, Line AE (W2691 *5/Kota) and Chinese Spring; infected with A. culture 80-E-2 [P28)] and B. pt. 126-5, 6, 7, 11 [p28]. Line AD carries Sr28 whereas Line AE has a second gene conferring IT 2 (see SrKt2). Pt. 126-5, 6, 7, 11 is virulent for both of these genes as well as Sr7b present in Kota.
C. Seedling leaves of a selection of Line AD infected with USDA Cereal Rust Laboratory pathotype LBBL. Courtesy AP Roelfs.
C. Seedling leaves of a selection of Line AD infected with USDA Cereal Rust Laboratory pathotype LBBL. Courtesy AP Roelfs.
Use in Agriculture
Sr28 is of limited use in current wheat breeding. However, it was the basis for resistance in cultivar Ceres released in the USA and rendered susceptible by race 56 in 1935.