INDUCTION OF MULTI-CELLULAR STRUCTURES IN ISOLATED MICROSPORES OF ROSES (ROSA HYBRID)
Isolated microspores can be switched from gametophytic pathway towards sporophytic development via stress treatments resulting in embryo formation. In this research work, isolated microspore culture was studied in order to induce multi-cellular structures in different rose cultivars. Important factors affecting viability of isolated microspores and formation of multi-cellular structures including isolation and induction media, pH of induction media, carbohydrates source, amino acids source and several stresses were studied. Heat shock for various times was evaluated on the induction of cell divisions leading to multi-cellular structures. The most responsive developmental stage of microspores (late uni-cellular) was determined using DAPI staining. The least infection of microspore cultures was observed when microspores were sterilized with sodium hypochlorite (3.5%) for 15 min. The best isolation medium was B medium containing 0.3 M mannitol. The highest viability of microspores was obtained in pH=6.2. The presence of lactalbumin hydrolysate in the induction medium increased frequency of symmetrical divisions and formation of multi-cellular structures. The highest ratio of multi-cellular structures was observed in microspores cultured in AT3 medium supplemented by maltose and stressed with heat shock (30°C) for 10 days in cultivar HAV1.
Oroojloo, M. and Shariatpanahi, M.E. (2012). INDUCTION OF MULTI-CELLULAR STRUCTURES IN ISOLATED MICROSPORES OF ROSES (ROSA HYBRID). Acta Hortic. 961, 479-486
rose, microspore, embryogenesis, multi-cellular structures, embryos, stress