Studies on the dormancy-awakening and -breaking in the two-rowed barley seed. I. Effects of sowing time and harvesting time on the dormancy-awakening.

Abstract

The effects of different sowing and harvesting time on the seed dormancy-awakening were studied, using two-rowed barley, cv. Asahi 19, Seijyou 17 and Satsukinijyou. The experiment of sowing time was undertaken on early, optimum and late ones in Tokushima prefecture. And the experiment of harvesting time was done at early, maturing and late stages with crops of optimum sowing time also in above-mentioned area. It was cleared that the dormancy-awakening of seeds was more obtainable with the case of optimum and late sowing compared With early one. On the other hand, it was clearly observed that the dormancy-awakening of seeds harvested at early stage delayed compared with both samples of maturing and late stages. Characteristic of seed dormancy-awakening of this crop was closely related with the thickness of seeds obtained throughout two experiments; it was earliest in seed of thickness over 2.8 mm, and delayed in the order of 2.5-2.6 and 2.2-2.4 mm of thickness. However, the relationships between the dormancy-awakening and thickness in seeds which were threshed soon after early harvesting showed somewhat smaller than in those threshed after air-drying. The results may be suggested that sowing and harvesting time may be participated strongly in seed dormancy-awakening on two-rowed barley.