The genetic status and conservation management of two cultivated bulb species extinct in the wild: Tecophilaea cyanocrocus (Chile) and Tulipa sprengeri (Turkey)

Tecophilaea cyanocrocus and Tulipa sprengeri are both extinct in the wild as a result of overharvesting by commercial collectors. Stocks of both species survive in cultivation in amateur collections, commercial nurseries and botanic garden collections. Whilst both species share a similar conservation history, the distribution of genetic diversity within cultivated material was unknown. To support the long-term conservation of both species the genetic diversity of the surviving stocks was assessed using amplified fragment length polymorphisms (AFLPs). This study revealed different genetic structures for the two bulb species. The Kew collections of T. cyanocrocus, originally obtained from a commercial nursery, Van Tubergen, are genetically highly uniform and the addition of samples from other collections has dramatically increased the level of variation. In contrast, the collections of T. sprengeri held at Kew since the early 20th century include representative genotypes covering the whole range of genetic variation found in this species and are probably the source of all other cultivated material. The results are discussed in relation to the management of these species to ensure their continued survival in cultivation.