2019 ASHS Annual Conference

Micropropagation of anthurium selections for field testing is an important component in the University of the Hawaii breeding program. Generating adequate material for field testing normally takes 3-4 years from callus initiation using newly unfurled foliage leaves or multiplication of accessory buds from greenhouse grown plants. However, some hybrids are recalcitrant in culture, whether from leaf lamina or accessory buds and presents a limitation on current field evaluations. Since thin cell layer culture was not previously used in our breeding program’s micropropagation protocol, we attempted to adopt this method for difficult to propagate varieties. Thin cell layers (1mm in thickness) from petioles of newly emerged leaves (leaves not fully expanded) were placed in modified MS medium supplemented with 0.2 mg l^-1 indole-3-butyric acid (IBA) and 0.1 mg l^-1 thidiazuron (TDZ) and then incubated in the dark until shoot initials develop. Proembryos (PEMs) emerged within 2-4 weeks of callus initiation. After PEM emergence, the stages of somatic embryo development were observed. In addition, accessory buds and leaves from the microplants were also evaluated as a potential explant source to expedite clonal increase of desired selections for field evaluation