Horticultural Research 12(1): 1-4 (1972)
Interaction of night temperature and day-length on floral initiation in Begonia dregei.
J. G. Waines

Plants of B. dregei were subjected to various night temperatures and to either a complete 16-h dark period or a 4-h night-break in the middle of the dark period. All the plants which received the night-break flowered. Some plants, which received temperatures below 18.3 deg C with no night-break, developed abnormal inflorescences.


Horticultural Research 12(2): 101-106 (1972)
Interaction of night temperature and day-length on root and shoot development and floral initiation in
Begonia socotrana,
and a comparison with flowering in Begonia X cheimantha.

J. G. Waines

B. socotrana bulblets were subjected to night temperatures of 10, 15.5, 21.1 or 26.6 deg C for 16 h. Treatment at each temperature consisted of a complete 16-h dark period or an 8-h day extension. The bulblets readily produced roots at temperatures of 15.5 deg or above, irrespective of daylength, this expression being most rapid at 21.1 and 26.6 deg. Shoots were readily formed at 15.5 deg or above, the optimal response being at 26.6 deg with short days.