Floral transition and dormancy release in tulip

The Netherlands is world leader in the flower bulbs industry and this demands solid fundamental research and continuous innovations. For the introduction of novel traits in breeding programs fast cycling and hence early or programmable flowering is desired. However, in tulip cycling is slow due to a long juvenile phase in which the bulblets are non-responsive to flowering inducing signals. After the switch from juvenile- to adult-vegetative stage, the shoot apical meristem can switch to reproductive development under suitable environmental conditions. Subsequently, a long period of cold is essential for dormancy release, followed by elongation of the stem and outgrowth of the floral organs. Tight control of the latter step is of great importance for the production of high-quality tulips for the cut flower market.

In this project we aim to get insight in the three main processes in relation to tulip flowering: (1) The juvenile-vegetative to adult-vegetative switch; (2) The adult-vegetative to reproductive phase transition; and (3) Dormancy release by winter cold. State-of-the-art technologies, including next-generation sequencing, are used to obtain insight in the regulatory mechanisms underlying the various aspects of flowering in tulip. The obtained data will be used to establish a flowering gene regulatory network for tulip, which will be compared to known flowering networks of plant model species. This should reveal how the network evolved and should shed light on the specific flowering behavior of tulip and bulbous plant species in general.