Comparative analysis of the homoeologous pairing effects of phKL gene in common wheat x Psathyrostachys huashanica Keng ex Kuo

In the natural Populations of common wheat landrace Kaixianluohanmai, there was a phKL gene which promotes homoeologous pairing of wheat-alien hybrids. In the present study, the effects of phKL gene on crossability and homoeologous pairing of Triticum aestivum x Psathyrostachys huashanica Keng ex Kuo hybrids were comparatively analyzed. The crossability of the hybrid between Sichuan wheat landrace Kaixianluohanmai and P. huashanica was highest in all the hybrid combinations with 3.18%. The hybrids T aestivum (Kaixianklohanmai) x P. huashanica showed a pairing configuration of 21.70 univalents + 2.68 rod bivalents + 0.34 ring bivalents + 0.06 trivalents + 0.02 quadrivalents and 3.54 chiasma per PMC at MI. However, the chiasma in hybrids of CS, CSph1b, CSph2a and CSph2b with P. huashanica was 0.56, 1.90, 0.87 and 0.60, respectively. Compared with the hybrids of CS, CSphlb, CSph2a and CSph2b with P. huashanica, a significant increase in the chiasma of homoeologous pairing was observed in the hybrids of T aestivum (Kaixianluohanmai) x P. huashanica. The effects were shown in the increment of rod bivalents, ring bivalents and trivalents and reduction of univalents. The results indicated that phKL showed a higher effect on promoting homoeologous pairing than ph1 and ph2 in T. aestivum x P. huashanica. The wheat landrace Kaixianluohanmai with phKL gene is probably a more desirable material for alien gene transferring than Ph2-deficiency lines.