Transmission of a chromosome from decaploid Agropyron elongatum that confers resistance to the wheat curl mite in common wheat
One of the group 6 chromosomes from Agropyron elongatum (Host) Beauv. confers resistance to colonization by the wheat curl mite (Aceria tulipae Keifer). The transmission of this chromosome was evaluated when added to or substituted for the group 6 homoeologues in two cultivars of common wheat (Triticum aestivum L.). Female transmission of the alien chromosome was similar for all substitutions (8.9%) but significantly less than expected. Male transmission (39.7%) differed among the substituted chromosomes and also was lower than expected except for the substitution involving chromosome 6A. These reduced transmission frequencies were reflected in lower than expected resistance in the F2 progeny. Both male (14.5%) and female (5.2%) transmission of the alien chromosome were reduced in monosomic additions. Meiotic analyses detected all expected F2 cytotypes but some of their frequencies differed among the substituted chromosomes. A possible wheat –alien translocation was detected in BC1F1 progeny.Key words: Agropyron elongatum, Thinopyrum, Elytrigia, Lyphopyrum, wheat curl mite, chromosome substitution.