Rythmical changes in the transcriptional activity of embryo chromatin during development and maturation of grain of triticale (cv. MT‐3) have been observed. The template availability and RNA polymerase (EC 2.7.7.6) 1 and II activities were high at the beginning of embryo development (20 to 30 days) and lowest at days 35 to 40 after anthesis, after which they increased to the end of maturation (60 days). Grains from three important periods of development (20, 40 and 60 days after anthesis; that is milk, wax and full ripeness, respectively) were used for germination, and chromatin was isolated from embryos and seedlings. A dramatic increase in the activity of both RNA polymerases and template availability was observed after 48 h of germination. The increase in template availability depended also on the ripeness stage of the grain used for germination.