2015 Volume 84 Issue 1 Pages 34-40
Tillering of winter wheat has been studied in warmer regions, but not widely in Hokkaido, which has a long snow period. This study was conducted firstly to develop a simple tiller tracking method, then using this method, to investigate the effect of tiller appearance time on panicle formation and grain yield in “Kitahonami”, a main winter wheat variety in Hokkaido. The results showed that a relationship between the time of tiller appearance and its ratio to develop ears (effective tiller) was easily identified by attaching a rubber band with different colors on each tiller at the time of tiller appearance. In the tillers with more than two leaves just before snow (robust stems before wintering, RS), the ratio of effective tillers was 75−100%. In the tillers that appeared in spring after the snow melted, the ratio was 0−4%. RS with ears had longer stem length and ear length than SS with ears. At harvest, although there was no significant difference between RS and SS in 1000-grain weight, grain weight per ear was significantly greater in RS than in SS, having more grains per panicle. The present results indicated that the increase in tillers appearing before wintering would increase the number of ears per plant and grains per ear, and thus the yield of winter wheat in Hokkaido.
