Production of virus-free plantlets by anther culture of Lilium x 'Enchantment'

Anthers of the Lilium x 'Enchantment', excised at the uninucleate microspore stage, were cultured on MS media containing 6% sucrose with auxin and cytokinin. When anthers were cultured on the medium with 2 mg l(-1) picloram and zeatin, 12-86% of them formed nodular calli. Anthers excised from greenhouse- and field-grown plants showed different responses: anthers of greenhouse-grown plants had a significantly higher capability to form callus and regenerate bulblets than those of field-grown plants. In anthers from greenhouse-grown plants, bulblet formation was dependent on the time at which anthers were excised from donor plants: anthers collected from early forced mother-plants had a higher capability of forming bulblet than others. All regenerated plantlets were diploid, which was substantiated by histological observation showing that the anther-derived calli originated from anther wall tissues. Virus tests by ELISA were made for 49 plantlets selected randomly at transplanting: 20 plantlets. (41%) were virus-free, and the rest showed positive reactions for lily symptomless virus, cucumber mosaic virus and/or tulip breaking virus. (C) 2001 Elsevier Science B.V. All rights reserved.