On the seed-vernalization of the cabbages (Brassica oleracea spp.)

Abstract

In the previous report, on an experiment where slightly germinated seeds of cabbage were exposed to u cold at 1±1°C for 20 days, the senior author made it clear that with the given variety of cabbage (cv. Yoshin) germinated seeds are in some degree susceptive to a vernalizing low temperature. And in this connection, though the result of the seed-vernalization was very meagre, an increased vernalization effect was expected with longer duration of cold treatment. Further, in recent years, gibberellin has proved itself an agency for vernalization in some biennial plants. Thus, an experiment has been carried out to examine the effects of a longer duration of seed-vernalization and chemical vernalization with gibberellin on the floral development in cabbage (cv. Yoshin), with the following methods and results. 1. Slightly germinated seeds of cabbage were kept at 1±1°C for 20 or 40 days (V20 and V40), half of them being given gibberellin (G) with a concentration of 5ppm throughout the vernalization treatment. The treated seeds(V20, V20G and V40) along with the control (VO and VOG) were sown on 20 March, 5 April and 20 April in 1960. 2. An accelerated floral development was seen in the vernalization lots, but between 20- and 40-day cold treatment no significant difference in vernalizing effect was observed. 3. Gibberellin applied during seed-vernalization failed to exhibit accelerating influence on the vernalization effect.