ENHANCED PLANT-REGENERATION FROM MICROSPORE-DERIVED EMBRYOS OF BRASSICA-NAPUS BY CHILLING, PARTIAL DESICCATION AND AGE SELECTION

Germination was rapidly induced in recalcitrant microspore-derived embryos of Brassica napus 'Topas' when they were exposed to a period of chilling (9-12 days at 4-degrees-C) or partial desiccation (rapid or slow air drying) prior to germination. In general, embryos thirty-five days old had the highest germination rates as compared to younger or older ones. Populations of embryos were induced to germinate at a rate of over 90% under specific temperature, desiccation and age conditions. Comparisons to an embryogenic B. napus winter line, F346, are made.