Acta Hortic. 1155. ISHS 2017. DOI 10.17660/ActaHortic.2017.1155.17 Proc. VI Int. Symp. on Production and Establishment of Micropropagated Plants Eds.: M. Beruto and E.A. Ozudogru 127 The improvement of Iris pallida propagation by somatic embryogenesis M. Lucchesini 1 , L. Bedini 1 , E.F. Florio 1,a , R. Maggini 1 , F. Malorgio 1 , B. Pezzarossa 2 and A. Mensuali‐Sodi 3 1 DiSAAA‐a, Viale delle Piagge 23, 56124 Pisa, Italy; 2 CNR, Istituto per lo Studio degli Ecosistemi, via Moruzzi, 1, 56124 Pisa, Italy; 3 Scuola Superiore Sant’Anna, Piazza Martiri della Libertà 33, 56127 Pisa, Italy. Abstract Iris spp. rhizomes are used in cosmetics and perfumery thanks to the presence of irones, violet-scented ketonic compounds. Between the several Iris species, Iris pallida Lam. is rich in irones and is the most valuable. In Tuscany, the cultivation of I. pallid is an integral part of the rural tradition. The aim of the research is to study the possibility of producing I. pallid plants by micropropagation and to overcome some critical factors of traditional cultivation. This study was based on the induction of somatic embryogenesis from flower buds and from leaf tissues of in vitro plantlets. Results demonstrated that the most suitable factors to begin the induction of embryogenic callus were the medium, a modified MS medium named i1B containing 0.1 mg L -1 Kinetin (Kin) and 1 mg L -1 2,4-dichlorophenoxy acetic acid (2,4-D), and the explant, the petal hafts (the base of the petals) of the flower buds. Another medium, named i1A, containing 1 mg L -1 Kin and 1 mg L -1 2,4-D was the most appropriate for the successive subcultures of the embryogenic callus among the tested ones. To induce and maintain embryo formation, an expression medium, named i2, containing a modified Knudson C macro elements, 1 mg L -1 Kin and 0.1 mg L -1 indole-3-butyric acid (IBA) was efficient. The protocol was subsequently improved with the use of in vitro microplant leaf tissues for the production of embryogenic callus. Transferring the embryos onto a modified MS medium named i3 with 0.1 mg L -1 of 6-benzyladenine (BA) and α-naphthaleneacetic acid (NAA), allowed us to obtain microplants to acclimatize ex vitro. As regards the presence of irones precursors, the HPLC chromatographic profile of the rhizomes from micropropagated I. pallida plants after acclimatization in open field, was comparable to that of rhizomes from mother plants cultivated in the place of origin. Keywords: embryogenic callus, irones, micropropagation, rhizome, Tuscany INTRODUCTION The genus Iris includes about 300 species of perennial herbaceous plants. Some Iris spp. have been cultivated for years for their rhizomes rich in violet‐scented ketonic compounds, much appreciated by the perfume and cosmetic industries. The scent of violet is due to the presence of four molecules: cis‐α‐irone, trans‐α‐irone, β‐irone and cis‐γ‐irone. The irones are a class of ketone compounds which are formed by oxidative degradation of iridals during a very long process lasting three years, which determines the high price of these essential oils used in cosmetics. Iris pallida Lam., a typical cultivation of Tuscany Region (Italy), mainly located on the hills of Chianti (S. Polo, Greve, Radda and Lamole) and on the slopes of Pratomagno (Pian di Sco, Castelfranco di Sopra and LoroCiuffenna), is very appreciated and requested by the perfumer and cosmetic industries and it is often preferred to those of other origins (Morocco, India, China). The rhizome is the marketable product and also the organ of propagation of this species. The traditional method of propagation consists in the division of rhizomes from which maximum 10 plants rhizome ‐1 in a year are obtained, but this production rate is not sufficient to satisfy the demand for raw material. Seed a E-mail: f.florio01@gmail.com