Agronomic and quality impact of a shortened translocation for wheat streak mosaic virus resistance

Abstract

Wheat streak mosaic virus (WSMV) is a mite‐vectored virus with substantial economic impact on wheat production. One of the effective sources of resistance to WSMV, Wsm1, is carried on a translocation from Thinopyrum intermedium. The original whole arm form of this translocation (T4DL·4JsS) was highly effective against WSMV but carried a substantial yield penalty in the absence of the virus. Shorter recombinants of the Th. intermedium translocation are now available. This study characterized the agronomic performance of near‐isogenic sib‐pair families in 10 yield trials using one of these shortened T4DL·4DS‐4JsS translocations, named “rec213,” in the absence of visible disease. This translocation had no effect on heading date, was associated with a modest reduction (≤ 4.8 cm) in plant height, and the translocation had a favorable effect (≤ 12.6%) on grain yield in those environments where highly significant genotype effects were detected. The translocation did not affect protein concentration or lactic acid‐sodium dodecyl sulfate solvent retention capacity, a measure of gluten quality. However, families with the translocation had slightly (≤ 5%) lower protein quality scores than paired families without the translocation. We do not expect this modest difference in quality to be a barrier to utilization of the rec213 translocation for Wsm1, but we encourage breeders to work within high‐quality genetic backgrounds when using the rec213 translocation and to monitor the quality of breeding selections. Improved codominant PCR‐based marker assays were developed to facilitate the use of the rec213 Wsm1 trait in breeding programs.