Resistance to C ephus cinctus N orton, the wheat stem sawfly, in a recombinant inbred line population of wheat derived from two resistance sources

• Published in: Plant breeding Vol. 133; no. 4; pp. 427 - 432
• Main Authors: Talbert, Luther E., Sherman, Jamie D., Hofland, Megan L., Lanning, Susan P., Blake, Nancy K., Grabbe, Reagan, Lamb, Peggy F., Martin, John M., Weaver, David K.
• Format: Journal Article
• Language: English
• Published: 01.08.2014
• ISSN: 0179-9541; 1439-0523
• DOI: 10.1111/pbr.12184

Abstract Several species of wheat stem sawflies ( WSS ) are pests of wheat, including C ephus cinctus Norton in North America. Larvae feed inside the stems and cut the stem near plant maturity. The primary means of control is resistance due to solid stems, largely controlled by a locus on chromosome 3B ( Q ss.msub‐3 BL ). Cultivars that differed for WSS resistance, but with similar stem solidness, were crossed to determine the genetic basis for the differences. The cultivar ‘Scholar’ is susceptible, while ‘Conan’ shows resistance. Scholar and Conan possessed different alleles at Q ss.msub‐3 BL . Both alleles conferred solidness, yet the Conan allele conferred higher WSS resistance. An allele from C onan on chromosome 4A also decreased infestation and stem cutting. The 3B and 4A alleles from C onan acted in an additive fashion to provide increased WSS resistance without increasing stem solidness. Stem solidness has long been used by breeders as a proxy for WSS resistance because of its simplicity. Our results suggest that other resistance mechanisms may complement solid stems.