The role of endogenous sucrose and exogenous trehalose in tomato floral transition influenced by light intensity under two types of white lights

MSc-thesis abstract (submitted 12 February 2018):
Floral transition is a prerequisite for reproductive success in plants.
Sugar is thought to play a dual role as energy source and signal in vegetative to reproductive phase transition.
Trehalose exists in majority of plants and its precursor, trehalose-6-phosphate(T6P), was found involved in floral transition in Arabidopsis.
Light is a critical parameter manipulated for seedling cultivation.

To investigate if and how endogenous sugar and exogenous trehalose mediate floral transition regulated by light, tomato
(Solanum lycopersicum L.) seedlings were cultivated under two photon flux densities (130 μmol m–2 s–1 and 60 μmol m–2 s–1) combined with white light rich in blue (highest peak at 455nm, WB) or white light rich in red (highest peak at 669nm, WR).
Exogenous trehalose (50mM, 100mM) was sprayed to manipulate internal T6P level which indirectly influence floral transition.

The results showed that:
1) high light intensity or WR promoted sucrose accumulation, accelerated the appearance of first inflorescence and promoted plant growth
2) trehalose suppressed sucrose accumulation mainly at low light intensity under white light with blue peak and delayed the appearance of first inflorescence at low light intensity under white light with red peak, plants growth was inhibited sprayed with trehalose.

Keywords: Solanum lycopersicum, high light intensity, white light rich in red, trehalose-6-phosphate, trehalose, sucrose, floral transition.