Studies in Short Day Vernalization of Barley : 4. Varietal difference in short day vernalization response under different daylength.

Abstract

To make clear the varietal difference in critical daylength of short day vernalization response of barley, sixteen naked varieties and seventeen covered varieties of barley were treated for three weeks under 8, 11, 14, and 20 hour daylength. Almost all the varieties showed the pronounced short day vernalization effect under 8 hour daylength. Under 11 and 14 hour daylength, however, there was difference in short day vernalization effect among the varieties. The varieties were classified into three grades, i. e. A, B, and C on their short day vernalization response under S, 11, and 14 hour daylength compared with that under 20 hour daylength. The trend of short day vernalization response of the varieties under 11 of 14 hour daylength which depended on their critical daylength was not parallel with that under 8 hour daylength. The schematic curve of short day vernalization response under different daylength was discussed.