THE EFFECT OF DIFFERENT PHOTOPERIODS AND TEMPERATURES FOLLOWING BULB INITIATION ON BULB DEVELOPMENT IN TROPICAL ONION CULTIVARS
Considerable bulb swelling took place after plants had been returned to short (8 h) photoperiods. Once bulb-scale formation had occurred, the swelling of these scales and the leaf bases of the bladed leaves surrounding them continued even in an 8-h photoperiod. Thus, photoperiod serves primarily to determine the fate of developing leaf initials. High temperature increased the rate of leaf senescence and hastened neck fall and maturity.