1994 Volume 63 Issue 3 Pages 603-610
Embryo development in ovules of intergeneric hybrids between E. wasabi cv. Takai (2n = 14) and A. rusticana 'Akame' (2n = 32) proceeded up to 30 days after pollination. In contrast, in the reciprocal cross of A. rusticana × E. wasabi, the embryo development was retarded and nearly all hybrid embryos degenerated by the 30th day after pollination. The hybrid ovules derived from E. wasabi × A. rusticana eventually yielded plantlets, whereas none were obtained in the reciprocal cross. We found that the MS medium for our ovule culture was superior to White's medium. The analysis of esterase isozyme and the chromosome numbers in the root tip cells, 2n=23, confirmed that the plants obtained by ovule culture were true hybrids of E. wasabi × A. rusticana. The morphological characteristics of the hybrid plants resembled those of E. wasabi.