Identification of a Triticum–Lophopyrum noncompensating translocation line and detection of Lophopyrum DNA using a wheatgrass specific molecular probe

Abstract

A Triticum–Lophopyrum translocation line was produced by a series of backcrosses between F1 hybrids derived from the cross Triticum aestivum × Lophopyrum ponticum (Podp.) Love and their progenies and bread wheat. Cytogenetic studies of progeny of crosses between the wheat-alien translocation line and doubled ditelosomics of the group 5 homoeologues of 'Chinese Spring' indicated that the translocated chromosome consisted of the long arm of chromosome 5B of wheat and short (S) arm of chromosome 6 (6AgS) of decaploid L. ponticum (2n = 70), which carries the gene(s) for resistance to colonization by wheat curl mite (Eriophyes tulipae Keifer). The frequencies of resistance to mite colonization were similar (p = 0.64) for F1 progenies from crosses between the noncompensating translocation line and double ditelosomics for 5A, 5B, and 5D and averaged 61.4%, but the frequency of F2 seeds per head (11.8) was lowest (p > 0.05) for hybrids involving 5B double ditelosomics. A repetitive DNA probe found abundantly in wheatgrass was also used to detect the Lophopyrum chromatin in this wheat-alien translocation plant. Although this probe hybridized faintly to wheat DNA in Southern hybridization, the probe's diagnostic hybridization to DNA from the wheat-Lophopyrum translocation plant clearly showed the presence of Lophopyrum DNA.Key words: wheat, Lophopyrum, wheatgrass, Eriophyes tulipae, translocation, hybrids, repetitive DNA sequence.