EFFECTS OF SEED OSMOPRIMING ON THE HARVEST TIME AND YIELD OF CUCURBITA PEPO L.

Seed osmopriming was evaluated as a means to improve early flowering, maturity time and yield of summer squash (Cucurbita pepo L.) grown from two sowing dates in 1990 (21 March and 6 April) and 1992 (21 March and 4 May). Seeds were primed in aerated solutions of polyethylene glycol 6000 (PEG) or KNO₃ at 2 or 3% (W/V) or KNO₃ + KH₂PO₄ (1:1) at 2 or 3% (W/V), at 18±1°C in the dark and then rinsed and dried. Field experiments were carried out at Siracusa (Italy). Plants from seeds primed in salts exhibited advances of 2.5 to 7.5 days in anthesis of first female flower and a significant improvement of early and middle yield, and in one case of total yield. In contrast, seed priming with PEG was ineffective.