Fig. 5.

Schematic representation of flower/fruitlet abscission following exposure of leaf or flower to abiotic stress. In the leaf, to abiotic stress inhibits development and decreases photosynthesis, leading to sugar starvation, perceived as unrecoverable by the fruit, which aborts. In flowers or fruitlets, the stress affects growth and photosynthesis. Consequently, the sugar balance between leaf and flower is altered and nutritional stress occurs. The sugar depletion induces an abscission signal leading to flower/fruit fall. Black arrows, leaf process; blue arrows, flower/fruit process; orange arrows, common process.