Virus resistance. Wheat Streak Mosaic Virus (WSMV)
The gene Wsm1, encoding resistance to WSMV, originates from a translocation of Agropyron intermedium into wheat (1). Among the first wheat lines containing Wsm1 was CI 17884, which has the short arm of chromosome 4D replaced by the short arm of chromosome 4 from A. intermedium. Further germplasm improvements were achieved by backcrossing CI 17884 into cultivar Karl to produce KS93WGRC27 (2), this line or lines derived from it are used to incorporate Wsm1 into wheat cultivars.
The translocated segment of A. intermedium containing the Wsm1 gene can be detected using the set of PCR primers STSJ15 (Talber et al, 1996). Since these primers will not amplify if the segment is absent, the set of primers G43 can be used as a positive control of the PCR reactions (see protocol).
Current backcrossing programs for WSMV resistance gene within the project
Laboratory codes: CO, Colorado State University; KS, Kansas State University; MT, Montana State University; NE, University of Nebraska
Additional information. Field testing
Sharp et al (4) reported a yield penalty in the lines carrying the translocation. But Wsm1 is the best source of WSMV resistance, compared to adapted cultivars or transgenic lines for the viral replicase or coat protein. Baley et al. (5) developed populations segregating for WSMV resistance and showed that noninoculated resistant lines had a slightly lower but significant decrease in yield compared to noninoculated susceptible lines. However, resistant lines presented only a 5% reduction in yield when inoculated with WSMV, compared to a 32% reduction for the susceptible lines.
1. Identification of alien chromatin specifying resistance to wheat streak mosaic and greenbug in wheat germ plasm by C-banding and in situ hybridization. Friebe, B.; Mukai, Y.; Dhaliwal, H. S.; Martin, T. J.; Gill, B. S. In: Theoretical and Applied Genetics, 1991. 81(3):381-389 [abstract]
2. Registration of KS93WGRC27 wheat streak mosaic virus resistant T4DL.4Ai#2S wheat germplasm Gill, B. S.; Friebe, B.; Wilson, D. L.; Martin, T. J.; Cox, T. S. In: Crop Science, 1995. 35(4):1236-1237
3. Development of PCR markers linked to resistance to wheat streak mosaic virus in wheat. Talbert, L. E.; Bruckner, P. L.; Smith, L. Y.; Sears, R.; Martin, T. J.In: Theoretical and Applied Genetics, 1996. 93 (3):463-467 [abstract]
4. Field Evaluation of Transgenic and Classical Sources of Wheat streak mosaic virus Resistance. Sharp, G. L.; Martin, J. M. ; Lanning, S. P.; Blake, N. K. ; Brey, C. W. ; Sivamani, E.; Qu, R.; Talbert, L. E. In: Crop Science, 2002. 42(1):105-110 [abstract]
5. Agronomic and End-Use Qualities of Wheat streak mosaic virus Resistant Spring Wheat. Baley, G. J.; Talbert, L. E. ; Martin, J. M.; Young, M. J. ; Habernicht, D. K. ; Kushnak, G. D. , Berg, J. E. ; Lanning, S. P. ; Bruckner, P. L. In: Crop Science, 2001. 41(6):1779-1784 [abstract]