CYTOMETRIC AND MORPHOMETRIC IDENTIFICATION OF DIPLOID, TETRAPLOID ANDPENTAPLOID PLANTS DERIVED FROM ACTINIDIA-ARGUTA (2N=4X) CROSSED WITH ACTINIDIA-DELICIOSA (2N=6X)

Interspecific crosses between Actinidia arguta (2n = 4x) and A, delici osa (2n = 6x) were carried out in order to transfer cold resistance fr om a wild to the cultivated kiwifruit species. Of the 65 progenies obt ained and analysed by how cytometry, 16 were diploid, one was tetraplo id and 48 were, as expected, pentaploid. Morphologically, the diploids can be distinguished from the pentaploids by their longer lamina. The existence of 5x progenies confirms the existence of gene flow between A. arguta and A. deliciosa, whereas the existence of 2x and 4x progen ies provides evidence for parthenogenesis within the Actinidia genus f ollowing an interspecific cross. The study demonstrates the utility of flow cytometry for genomic analysis of progenies derived from intersp ecific crosses. Possible uses of both sexual and parthenogenetic proge nies in the breeding and genetics of kiwifruit are discussed.