THE INFLUENCE OF ROOT AND AIR TEMPERATURE ON YOUNG CUCUMBER PLANTS

Three experiments with young cucumber plants were carried out in a growth chamber under controlled conditions.

1. The influence of both root and air temperature on growth of root and top.
   
2. The influence of varying root temperature.
   
3. The influence of different root temperatures to parts of the root.
   

The results from experiment 1 are shown in three dimentional diagrams and show optimal root temperatures and air temperatures between 20°C and 30°C.

The results from experiment 2 show that when keeping the day root temperature or the night root temperature lower or higher than the optimal constant root temperature it will cause a decrease in top growth, but not in root growth, when temperature difference is small.
If day root temperature is low and night root temperature is optimal, root growth will decrease more than if keeping night root temperature low.

The results from experiment 3 show that if keeping one half of the root system at lower or at higher temperature than optimal temperature to the other half of the root system, one gets a decrease in top growth, but not necessarily in root growth, unless the one half of the root is very low in temperature.

Although the results from the last two experiments are based on five replicates only, and therefore the statistical calculations are not very sure, it seems worth-while to discuss the trends and tendencies in the results.

Working-party on Greenhouse Cucumber

P. Karlsen

https://doi.org/10.17660/ActaHortic.1981.118.11