In-vitro regeneration of Calendula maritima Guss. (Asteraceae), a threatened plant endemic to Western Sicily

Calendula maritima is a critically endangered endemic plant of Western Sicily. Besides habitat destruction, the hybridization with the contiguous congener species C. fulgida is a major threat to its conservation. For this reason, seed-based propagation and seed storage are not appropriate for conservation purposes. In the present paper we describe a rapid and prolific In vitro plant regeneration method by direct organogenesis from leaves of C. maritima. Leaf explants were cultured on solid Murashige and Skoog (MS) medium in the presence of several plant growth regulator combinations. The best shoot multiplication rate (2.5 shoots/explant) was obtained on the medium containing 4.4 mu M 6-ben…