To isolate genes related to resistance to Erysiphe graminis DC. ex Merat f. sp. tritici Em. Marchal in wheat (Triticum aestivum L.), differential display analysis was conducted for mRNA extracted from the seedlings of the wheat-Haynaldia villosa 6VS/6AL translocation line 92RI37 that contains the powdery mildew resistance gene Pm21. A full-length cDNA named TaPK1 was isolated. BLAST analysis revealed that it was significantly homologous to Glycine max (L.) Merr. protein kinase (GmPK6) cDNA. TaPK1 encodes a 416 amino acid long polypeptide, which belongs to serine/threonine protein kinase family, also has tyrosine kinase specificity. TaPK1 is a novel protein kinase from wheat.
Alien chromosomes of twelve giant spike wheat germplasm lines were identified by C-banding, genomic in situ hybridization (GISH), sequence characterized amplified region (SCAR), and random amplified polymorphic DNA (RAPD). All lines showed a chromosome number of 2n = 42, five of them carried both a pair of wheat-rye (Triticum aestivum-Secale cereal) 1BL/1RS translocation chromosomes and a pair of Agropyron intermedium (Ai) chromosomes, three carried a pair of Ai chromosomes only, three others carried a pair of 1BL/1RS chromosomes only, and one carried neither 1BL/1BS nor Ai chromosome. Further identification revealed that the identical Ai chromosome in these germplasm lines substituted the chromosome 2D of common wheat (T aestivum L.), designated as 2Ai. The genetic implication and further utilization of 2Ai in wheat improvement were also discussed.