Flowering in Dactylis glomerata. II. Interaction of temperature and photoperiod

Abstract

Controlled environment studies investigated the interaction between temperature and photoperiod in relation to floral initiation in seedling populations of the temperate perennial grass Dactylis glomerata L. High temperature inhibited flower formation, but this effect was confined to the early part of the terminal LD treatment, i.e, to the actual transition of the shoot apex from vegetative to floral development. During earlier stages of vegetative growth, including SD vernalization, high temperature was not inhibitory. Of the treatment parameters studied, two exerted a dominant influence on the level of flowering. These were (i) the duration of SD vernalization, and (ii) the temperature level during the terminal LD treatment. A model is presented to explain flowering response in terms of an interaction between these components.