Crown Buds Limit Floral Productivity In Gentians

The development of crop management strategies to schedule floral productivity in gentians is limited by the lack of information on the physiology of their growth and the development of floral shoots. Since floral shoots arise from buds on the crown, the timing of their appearance, emergence and development to flowering were tracked over time, using the variety ‘Spotlight’ growing outside or within a greenhouse heated to 15°C. Although different types of buds were identified, only pre-formed primary-crown buds produced flowering shoots. Irrespective of the growing environment, 27% of these crown buds did not emerge, and these were subsequently shown to be under correlative inhibition from developed shoots. The appearance of new crown buds for the following season’s flower production occurred over 8 months, from early summer to early winter. Histological investigations revealed that crown buds were initiated adventitiously on the crown, with axillary buds subsequently resulting in the formation of crown bud clusters.