GISH analysis of introgressive hybridization using aneuploids as male parents in Lilium

Lilium produce fritillaria-type embryo sacs and it is easy to obtain aneuploids from 3 x × 2 x /4 x interploidy hybridization. However, there are no reports about introgressive hybridization using aneuploids as male parents because gene imbalance or irregular abnormal meiosis are detrimental to the viability and fertility of aneuploid lilies. In the present study, two partial male fertile aneuploid lines, J1834 and J1859, were selected and crossed with diploid (AA) and tetraploid (AAAA) Asiatic lilies using normal pollination and embryo rescue, and genomic in situ hybridization (GISH) was used to analyze the two aneuploids and their progenies. The GISH results indicated that the formula of genomic composition of J1834 was “LAAA 2− ”, i.e., 2 n = 4 x − 2 = 46 = 9 L + 37 A, and that of J1859 was “LAAA 5+ ”, i.e., 2 n = 4 x + 5 = 53 = 4 L + 48 A + 1 L/A; all the progenies from the “2 x /4 x × aneuploid” were aneuploid and the alien L-chromosomes in the aneuploid progenies were much less than their aneuploid parents, and three of them, 20085-1, 20085-11 and 20085-12, contained only one small alien L-chromosomal segment. It was concluded that aneuploids could be used as parents to transfer one or a few desirable genes into new cultivars in lily introgression breeding.