Cyto-morphological evidence for segmental allopolyploid origin of Teasle gourd (<Emphasis Type="Italic">Momordica subangulata</Emphasis> subsp. <Emphasis Type="Italic">renigera</Emphasis>)     

L. K. Bharathi  Vinod  A. D. Munshi  T. K. Behera  Shanti-Chandrashekaran  J. J. Kattukunnel  A. B. Das  Vishalnath 《Euphytica》2010,176(1):79-85

Teasle gourd [Momordica subangulata Blume subsp. renigera (G. Don) de Wilde, 2n = 56] exhibits morphological characters found in both M. dioica (2n = 28) and M. cochinchinensis (2n = 28). Morphological analysis of M. subangulata subsp. renigera suggests an allopolyploid origin. We present evidence elucidating the genomic relationships between M. dioica, M. cochinchinensis and M. subangulata subsp. renigera. A triploid M. dioica × M. subangulata subsp. renigera hybrid had an average of 12.76 bivalents, 13.84 univalents and 0.88 trivalents at metaphase I, while the M. cochinchinensis × M. subangulata subsp. renigera hybrid had an average of 13.08 bivalents, 12.96 univalents and 0.96 trivalents. F₁ hybrids of the two diploid species (M. dioica × M. cochinchinensis) showed an average of 9.12 bivalents and 9.76 univalents, suggesting that the genomes of these species are only partially homologous. A higher number of bivalents in the triploid hybrids suggests that M. subangulata subsp. renigera is a segmental allopolyploid of M. dioica and M. cochinchinensis and that its genomes have diverged from the parental genomes.  相似文献