Table I.
Environmental conditions in the greenhouse during the four growing periods
| Experiment | Air Temperature Day/Night | Cumulative PPFD | Duration of Expansion with VPD > 3 kPa | Photoperiod |
|---|---|---|---|---|
| °C | mol m−2 d−1 | % of total | h | |
| April 1995 | 22.0 /15.9 | 18.1 | 0.0 | 14.5a |
| July 1995 | 29.0 /22.5 | 26.6 | 11.3 | 15.0 |
| September 1995 | 25.9 /21.3 | 19.7 | 0.2 | 13.5 |
| July 1996 | 26.5 /22.4 | 26.7 | 1.4 | 15.0 |
Means were calculated over the period of expansion of leaf 8. Duration of periods with high air vapor pressure deficit (VPD) was calculated relative to total duration of expansion.
a
Additional light was given in the greenhouse during the expansion of the leaf.