Selection of distant hybridization parents for triploid LA hybrid lilies

In order to investigate the applicability of LA hybrids as the breeding parents and select parents with a better fertility in LA×Asiatic lilies, 62 crossings were conducted with 26 LA cultivars and 10 Asiatic cultivars used as parents. Genomic in situ hybridization (GISH) technique was applied for hybrid identification and analysis of chromosomal composition in some hybrid progenies. Main results were obtained as follows: 1) LA triploid hybrids are usually male-sterile, but they can be crossed with diploid or tetraploid Asiatic hybrids as a female parent. 2) Compared with diploid Asiatic hybrids (AA), tetraploid Asiatic hybrids (AAAA) have a better fertility when crossed with LA hybrids. 3) Seven cross combinations with a better fertility were selected: ‘Nashville’בNello’,‘Freya’בValdiSole’,‘Desiderio’בDetroit’,‘Samur’בNello’,‘Batistero’בRegata’,‘Roussea-u’בVal di Sole’ and ‘Ercolano’בBenlica’. The results of 62 crossings revealed that 3 LA hybrids as female parents (‘Freya’,‘Nashville’ and ‘Orange Tycoon’) and 6 Asiatic hybrids as male parents (‘Val di Sole’,‘Nello’,‘Regata’,‘Detroit’,‘Benlica’ and ‘Black out’) had high seed-setting rates. 4) The chromosomes recombination between aneuploid eggs that allotriploid hybrids produced and the genomes has high potential in introgression breeding. This study further develops the breeding potential of triploid LA hybrids, and lays the foundation for breeding of commercial lily varieties.