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There are thousands of Narcissus cultivars, however; their genome compositions are not so clear, except that their ploidy levels are extensively investigated. The present study analyzed eight popular cultivars using GISH or/and FISH. The present results clearly revealed their genome compositions: 'Bridal Crown' was diploid (2n = 2x = 17 = 10 + 7 = AE) rather than aneuploid, 'Jinzhanyintai' was autotriploid (2n = 3x = 30 = 10 + 10 + 10 = AAA) rather than allotetraploid or hexaploid, 'Tête-à-Tête' was allotriploid (2n = 3x = 24 + B = 10 + 7 + 7 + B = AEE), 'Cultivar X' was also allotriploid (2n = 3x = 24 = 10 + 7 + 7 = AEX), and 'Dutch Master', 'Replete' and 'Queen's Day' were all autotetraploid (2n = 4x = 28 = 7 + 7 + 7 + 7 = EEEE). Together with other reports, we concluded that 'Tête-à-Tête' contained one genome of Narcissus tazetta, one genome of Narcissus cyclamineus, and one genome of Narcissus pseudonarcissus, and that 'Pink Parasol' was aneu-autotetraploid (2n = 4x + 2 = 30 = 7 + 7 + 7 + 7 + 2 = EEEE+2) rather allotetraploid (2n = 4x = 10 + 10 + 5 + 5 = CCDD). Based on the cultivar's genome composition and origin, it is concluded that distant hybridization, sexual polyploidization and chromosome doubling play different roles in breeding modern Narcissus cultivars. [ABSTRACT FROM AUTHOR]

Lilium brownii var. viridulum (BB) and L. davidii var. unicolor (AdAd) are grown for edible in China, but their breeding lags far more than other ornamental lily breeding. To improve the situation, F1 BA hybrids were used as seed parents to cross with AdAd and other diploid Asiatic lilies (AA). The results showed that the F1 BA hybrids could produce BC1 progenies. The average seedlings obtained from the combinations per fruit were very variable from 1.7 to 22.5, indicating that their compatibilities were different depending on their males. Among the 18 progenies with genomic in situ hybridization (GISH), ten of them were diploid (2n = 2x = 24), two are aneuploid-near diploid (2n = 2x ± 1), and other six were allotriploid (2n = 3x = 36); and all of them contain much more recombinant chromosomes and breakpoints than other distant lily hybrids. We concluded that F1 LA hybrids produced much more n functional egg cells than 2n functional egg cells and this would pay a new way to realize lily ingression breeding at diploid ploidy level. [ABSTRACT FROM AUTHOR]

Aneuploid lilies (Lilium) could be obtained from the LAA/LAAA × AA/AAAA hybridization; however, the characteristics of their meiosis and fertility has not been reported. In this study, an aneuploid lily, J1614, was extensively investigated for its microsporogenesis, fertility and functional eggs using conventional and modern cytogenetic methods. The results indicated that J1614 was an aneuploid Longiflorum-Asiatic (LA) lily (2n = 48 = 7 L + 39 A + 2 L/A) while 'Pearl Jason' was an autotetraploid Asiatic lily (2n = 48 A); L-chromosomes of J1614 usually formed univalent while A-chromosomes associated not only predominantly trivalents, but also tetravalents, bivalents, and even univalent at metaphase I as well; clearly, both univalents and other associated chromosomes were separated and moved to opposite poles at anaphase I; besides, lagging chromosomes and micronuclei were observed during microsporogenesis. Hybridization showed that J1614, regardless of its male sterility, had better partial female fertility when tetraploid a lily was used as male than when a diploid as male. The nine seedlings of J1614 × AAAA were all aneuploid with variable total chromosomes ranging from 46 to 53, meaning that the functional eggs produced by J1614 contained variable chromosomes ranging from 22 to 29. Based on the present results, we concluded that once good lines are selected from aneuploid lilies, they may not only become cultivars through vegetative propagation, but also become parents to breed new aneuploids and realize introgression breeding. In addition, the mechanism of abnormal meiosis of aneuploid lilies was hypothesized. [ABSTRACT FROM AUTHOR]