Abstract:
For shortterm (minutes to hours) temperature optimization in greenhouses plant growth models are needed, which estimate shortterm plant reactions and predict, how shortterm reactions contribute to yield, realized several weeks later.
For the greenhouse crop kohlrabi (Brassica oleracea gongylodes L.) shortterm reactions to temperature are presented, which are not only caused by the temperature level, but also specifically by temperature changes.
The dynamic shortterm plant reactions showed differences compared to the steady state longterm reactions.
The differences were due to temperature aftereffects and plant adaptation to the changed temperature.
It follows that for kohlrabi a model, which is parameterized with longterm average values of plant growth and climatic factors, can not be used to derive optimal shortterm temperature set points.
Conclusions for shortterm temperature optimization are discussed.
