Study On Hybridization And Chromosome Doubling For Potted Asiatic Lilies (Lilium)

The Asiatic lily,originated from intra-section hybridization of the Sinomartagon of Lilium, is the biggest lily cultivar group. Polyploid cultivars are not that common in potted Asiatic lilies based on our research on the cultivars introduced from the Netherlands. There is probably a good prospects in tetraploid potted lilies because of their robust plants,big flowers and other merits.We made some crosses among the following Asiatic lilies as parents:100047:’Pe-tit Brigitte’(10A012)×’Black Bird’(10A008),100048:’Orange Pixie’(10A011)x’Black Bird’(10A008),100092:’Petit Brigitte’(10A012)×’Pollyanna’(A26). Then,the scales of the progenies obtained were treated with Oryzalin, the main results are as follows.(1) The male parents are ’Black Bird’(10A008) and’Pollyanna’(A26),their pollen germination rate were80and36.(2) The fruits of three crosses all developed well;27,22and47seedlings were obtained from embryo rescue respectively.(3) For No.100047,the best density of Oryzalin is0.005%, reaching a doubling rate of23%;while No.100048and No.100092can be doubled at the rate of19%with0.002%and0.003%Oryzalin respectively.(4) Tetraploid regenerated seedlings,doubled by Oryzalin, have wider and thicker leaves than diploids in No.100048. But similar phenomenon did not appear in No.100092or No.100047,scilicet,non obvious morphological differences were observed in the two series.(5) FISH not only confirmed the chromosome doubled plants, but also indicated that the sites of45S rDNA were doubled at the same time,which consistent with the expected result. However, the doubled No.100047has only47chromosomes with a loss of the No.1chromosome.The loss can be ascribed for not being doubled during the inducing treatment.