DIFFERENTIAL FERTILITY AND TRANSMISSION OF MALE AND FEMALE GAMETES IN ALLOPLASMIC WHEAT HYBRIDS

Alloplasmic Triticum aestivum L. cv. Selkirk lines having cytoplasms of five D-genome Aegilops species were crossed reciprocally with euplasmic T. durum Selection 56-1 to study differential cytoplasmic effects on pentaploid hybrids. Pollen fertility of the alloplasmic and euplasmic pentaploid hybrids ranged from 23.0% to 46.6%, and from 84.9% to 91.1%, respectively. Significant differences in seed-set and in the viability of backcrossed seed were observed between the euplasmic and alloplasmic pentaploids as well as among the five alloplasmic pentaploids. The pentaploid with Ae. squarrosa cytoplasm did not transmit 14-chromosome male gametes. The cytoplasms of Ae. squarrosa, Ae. cylindrica and Ae. ventricosa were similar to one another in their differential effects on the transmission of euploid and aneuploid male gametes numbers, and similarly the cytoplasms of Ae. crassa and Ae. juvenalis resembled each other.