Sr35

(McIntosh et al., 1984) (Plate 3-36)

Synonym

SrTm1 (Valkoun et al., 1986).

Chromosome Location

3AL (McIntosh et al., 1984). Sr35 was located 41.5 cM from the centromere and showed 1% recombination with R2 derived from the same source.

Low Infection Type

0; to ;.

Environmental Variability

None reported.

Origin

T. monococcum. Sr35 is present in a selection from The University of Sydney accession C69.69 (P.I.264935) and in the Canadian accession G2919 (McIntosh et al., 1984). It was independently transferred from these accessions to tetraploid and hexaploid wheats in Canada and to hexaploid wheat in Australia.

Pathogenic Variability

Sr35 is effective against most Australian pathotypes except cultures of standard race 126 and a mutant culture (82-L-2) isolated during studies in the greenhouse. Many North American cultures are avirulent (McIntosh et al., 1984). In the survey of Huerta-Espino (1992) virulence was found in Ethiopia, Kenya, the Malagasy Republic, Nepal, China, Argentina, Brazil and Chile.

Reference Stocks

i: C81.42 = R.L.6071*7/G2919 Sr9e (McIntosh et al., 1984).

v: M80.3990, M80.4635, M80.4636 derived from C69.69 (McIntosh et al., 1984). Backcross derivatives of cvv. Zlatka and Yubinlenaya (Valkoun et al., 1986).

tv: Stewart*8/G2919 Sr9e (McIntosh et al., 1984).

dv: Components of C69.69 = P.I.264935; G2919 (McIntosh et al., 1984).

Source Stocks

Backcross derivatives produced at The University of Sydney, for example Sr35/3*77W549, Sr35/4*Canna.

Seedling leaves of (L to R): M80.3990 (an Australian hexaploid derivative of C69.69), C81.42 (R.L6071*5/G2919), 103335 (Sr35/3*77W549), 77W549, 67093 (Sr35/4*Canna), Canna and Chinese Spring; infected with A. pt. 34-1, 2, 3, 4, 5, 6, 7, B. culture 82-L-2, a mutant derivative of 34-1, 2, 3, 4, 5, 6, 7 virulent for Sr35 and C. pt. 126-5, 6, 7, 11 which is also virulent for Sr35. The first, second, third and fifth lines carry Sr35. The second and third cultures are virulent for Sr3S but note the resistance of 77W549 to culture 82-L-2 and of various wheats to pt. 126-5, 6, 7, 11. The isolate of 82-L-2 used for this photograph was contaminated with leaf rust, visible on some leaves.

 

Use in Agriculture

Although not yet exploited, Sr35 should have a role if used in gene combinations. White-seeded derivatives with Sr35 were recovered in the genetic studies conducted by McIntosh et al. (1984).