EFFECT OF PHOTOPERIOD AND TEMPERATURE ON SEEDLING DEVELOPMENT OF OLLI AND VANTAGE BARLEY

Abstract

A photoperiod-sensitive cultivar (Vantage) and a non-sensitive cultivar (Olli) of barley (Hordeum vulgare L.) were grown under photoperiods of 8, 16, and 24 hr at 13 and 24 °C to study the relationship between apical and vegetative development of the seedling. The high temperature tended to accentuate the effect of short days in extending the vegetative period before floral initiation, but caused a shortening of the period between the formation of double ridges and the first arrival of a node at ground level (NGL). At 13 °C NGL coincided with the formation of stamen initials, but at 24 °C NGL occurred at progressively earlier stages of floral organogenesis as daylengths were shortened to 16 and 8 hr. The results suggest that almost invariably NGL can be used to indicate that floral initiation has occurred in a barley plant, but cannot be used to indicate stage of floral organogenesis under all conditions.