One of the most important ornamental plants for the flower bulb industry in the Netherlands is tulip, a monocot belonging to the Liliaceae family. When temperatures are increasing during spring/summer the development of the new floral bud in the bulbs is initiated and a complete flower primordium will be formed around September. After completion of the flower inside the bulb (Stage G), the bulb will undergo a period of dormancy. In this period temperatures are low and mobilization of sugars is occurring as preparation for stem elongation. The regulation of the induction and release of dormancy in tulip bulbs is poorly understood. So far only a correlation was found between cold temperatures and starch degradation upon release of dormancy. The degradation of starch is accompanied by increase α-amylase activity, making this a suitable marker for dormancy release (Lambrechts et al. 1994). According to Komiyama and collegues (2005) only one single copy of the α-amylase gene is present in the genome of Tulipa gesneriana. Monitoring the expression of this gene might give more insight in the exact moment of dormancy release in the bulbs. This creates the possibility to study dormancy in more detail at the physiological and molecular levels.
The aim of this project is to follow the enzyme activity and gene expression of α-amylase during the period of dormancy and to link it to morphological markers.
Enzyme assays, sugar content measurements, cloning, RNA extraction, RT-PCR and expression analysis by qPCR.
The project is suitable for both BSc and MSc students and preferably for an internship of a period of at least 4 months. Preferred period of the internship will be between September and February, as this is the period of dormancy in tulip bulbs. Knowledge and/or experience with biochemistry and molecular biology is an advantage as it will be widely used.