Phytohormone gibberellin controls onset of plant development and flower formation

The Wagner lab has uncovered dual opposite roles of the phytohormone gibberellin in the events that lead to formation of flowers, fruits, and seeds. Elevated gibberellin promotes termination of the vegetative phase and triggers bolting, while reduced gibberellin triggers flower formation.  These two events are coupled in that gibberellin increases the expression of genes encoding transcription factors, including Squamosa promoter binding protein (SPL) and LEAFY, that promote the transition to inflorescence development. 

Once these have accumulated, reducing gibberellin levels lead to upregulation of critical factors for making flowers such as APETALA1. The researchers have shown that induction of a gibberellin catabolism enzyme, ELA1, to lower gibberellin levels, or of gibberellin insensitive versions of DELLA proteins, or application of paclobutrazol at the right time (after bolting and LEAFY/SPL accumulation) will trigger promote flower, fruit, and seed formation. 

Properly timed lowering of gibberellin should be particularly useful to enhance yield in woody perennials (fruit trees etc.), but also likely in annual plants.

Optimizes crop yield over existing formulations and techniques

• Increase seed yield by adjusting gibberellin metabolism
• Optimize pollination
• Control onset of flower, fruit, and seed formation
• Biofuel production