Genetic identity of putative Linnaean plants: Successful DNA amplification of Linnaeus's crab apple Malus baccata

Abstract

AbstractAdvancements in molecular techniques enable us to extract DNA from historic herbarium specimens and facilitate genetic comparisons between herbarium material and living plant collections. These recent advances offer an exciting opportunity for identifying extant Linnaean plants by genetic comparisons of Linnaeus's own herbarium specimens with potentially remnant plants from his cultivations. DNA from the lectotype of Malus baccata (L.) Borkh. in the Linnaean Herbarium was successfully extracted and amplified for five of twelve loci of microsatellites. Results of genetic comparisons with M. baccata trees from Linnaeus's Hammarby, Sweden, show that the trees at Hammarby are closely related to each other, but not to the lectotype, which is closer to material from Russia. This suggests that Linnaeus received M. baccata from more than one source. Although not close to the lectotype and not represented by a specimen in the Linnaean Herbarium, the extant M. baccata at Hammarby may still represent Linnaean plants, that were grown by Linnaeus himself, or the descendants to such plants. Future studies on the almost 50 living, potential Linnaean plants may reveal an invaluable biological, scientific and cultural heritage from the era that saw the rise of systematic biology.