Sr29

(Dyck and Kerber, 1977b) (Plate 3-30)

Synonym

SrEC (McIntosh et al., 1974).

Chromosome Location

6DL (Dyck and Kerber, 1977b); 6DS (Zeller and Oppitz, 1977); Sr29 appeared to be genetically independent of the centromere (Dyck and Kerber, 1977b).

Low Infection Type

1 to 3.

Environmental Variability

Low (Roelfs and McVey, 1979).

Origin

Common wheat. Sr29 appears to be a gene of European origin.

Pathogenic Variability

Roelfs and McVey (1979) reported that a few avirulent cultures gave low infection types that were slightly higher than usual. Huerta-Espino (1992) reported virulence only among cultures from western Asia, eastern Europe, Egypt, Ethiopia and Turkey.

Reference Stocks

i: Prelude/8*Marquis//Etoile de Choisy (Dyck and Kerber, 1977b).

v: Etoile de Choisy W3550 Sr23 (McIntosh et al., 1974).

Source Stocks

Hela; Mara; Slavia; Vala (Bartos and Stuchlikova, 1986). Moisson Sr23 (Luig, 1983).

 

Seedling leaves of (L to R): Etoile de Choisy, Prelude/8*Marquis//Etoile de Choisy, Marquis and Chinese Spring; infected with A. and B. pt. 21-1, 2, 3, 7 and C. pt. 126-5, 6, 7, 11. A. and C. were incubated at 23/20°C and B. at 27/23°C. The brown necrosis often present in pustules on Etoile de Choisy is due to Sr23 which is also present in this cultivar. With Australian pathotypes, Marquis is usually less susceptible than Chinese Spring. The uppermost uredium on the second leaf in A. is a leaf rust contaminant.

 

Use in Agriculture

Adult plants with this gene are moderately susceptible (Roelfs and McVey, 1979). The gene has been used for stem rust control in European wheats, but has not been incorporated into North American winter wheats or spring wheats grown outside of Europe.