Effects of the treatments by synthetic strigolactone (SL) and SL-enriched biostimulant on tomato fruit development.

Strigolactones (SLs) are a class of plant hormones with various functions in plant development and in the interaction with (micro) organisms in the rhizosphere. As developmental regulators the SLs control above- and below-ground morphology, the inhibition of shoot branching, the modulation of the root morphology and the promotion of the shoot secondary growth.  It follows that SL-depleted or insensitive plants show an altered morphology (stunted and bushy), a prolongate vegetative development and a delayed in reproductive transition. This latter aspect leads to a reduced number of flowers fruits and seeds in Solanum lycopersicum. To know the effects of an excess of SLs on the reproductive phenotype in tomato we analyzed the results of the exogenous treatments with rac-GR24, a synthetic strigolactone and with a biostimulant SL-enriched produced by StrigoLab. Preliminary data indicate that the treated plants show a preponed flowering and an earlier harvestable fruit compared to mock-treated plants.