Phenotypic and cytological variation among plants derived from anther cultures ofLilium longiflorum

Summary Anther culture of the Easter Lily (Lilium longiflorum; 2n=2x=24) was attempted in order to evaluate its potential in generating haploids for the production of hybrid cultivars. The effects of genotype, temperature (low temperature treatment of buds and high temperature treatment of cultures), sucrose concentration and growth regulators were tested. The most important factors for callus induction were the genotype and the presence of 2,4-dichlorophenoxyacetic acid. Pre-treatments at low or high temperature had no apparent effect, while high sucrose concentration was inhibitory. Callus was derived from 28 of the 108 genotypes tested and plants were regenerated. Phenotypic variations were observed among these regenerants. Somatic chromosome numbers were determined in 42 plants derived from 10 donor genotypes. Thirteen plants were diploid and 29 were mixoploid with chromosome numbers ranging from 11 to 26. Four of the mixoploid plants had a high proportion of cells with haploid chromosome numbers, particularly at early stages of development. Meiosis was examined in plants with flower buds. Most plants had 12 bivalents at Metaphase I, but also aneuploids were observed. Other irregularities included bridges and laggards at Anaphase I. The occurrence of high frequencies of haploid cells (up to 80%) in root tips suggests that some plants may be of gametic origin. Research was supported by the Easter Lily Research Foundation, the Ohio Floriculture Foundation, the Gloeckner Foundation and the Oregon Agricultural Experiment Station (technical paper no. 8398).