Chrysanthemum: Ex vitro to in vitro to ex vitro

Greenhouse chrysanthemums are important cut flower plants. Tissues in two physiological states (greenhouse and in vitro) have different growth patterns and regeneration capacities. This study presents an ideal optimized cyclic program for the acclimatization of ex vitro chrysanthemum (Dendranthema grandiflora Ramat. Kitamura) stem or leaf explants or excised shoot tips to in vitro conditions, a maximized shoot regeneration protocol of these in vitro explants and the return of established in vitro plants and their successful acclimatization to greenhouse conditions, serving once again as mother plants, or for flowering. Greenhouse or in vitro-derived explants utilized for genetic transformation studies are often exposed to great stresses: physical damage in electroporation, particle bombardment or sonication; infection and competition for survival in Agroinfection; salt or ion stress due to stress-induction studies; mutagenic damage (by physical or chemical mutagens); antibiotic stress in selector gene selection following genetic transformation. Many of these demonstrate a change in regeneration capacity, improved by changes in the caulogenic and rhizogenic regeneration media.