STIMULATION OF THE EFFECTIVENESS OF PARTIAL VERNALIZATION OF ISOLATEDEMBRYOS OF WINTER-WHEAT BY THE EXTRACTS FROM PLANTS OF DIFFERENT STAGES OF GENERATIVE DEVELOPMENT

The influence of the extracts from immature grains and ears and from v ernalized and non-vernalized seedlings on the effectiveness of partial vernalization of isolated embryos of winter wheat var. Grana under in vitro conditions was examined. The effectiveness of vernalization was estimated on the basis of the number of plants capable of generative development as well as the number of days of plants growth to heading. Extracts from immature ears, grains and vernalized seedlings stimulat ed the generative development of plants, while extract from non-vernal ized seedlings retarded to a small extent the heading of plants. The e xtract obtained from immature ears proved to be the most effective and accelerated the heading of plants by, 20 up to 40 days. It also signi ficantly increased the percentage of plants capable of flowering after incomplete vernalization.