THE OPTIMIZATION OF AIR TEMPERATURES FOR GREENHOUSE CUCUMBERS - AN EVALUATION OF DIFFERENT FARMING STRATEGIES

ISHS Acta Horticulturae 260: International Symposium on Growth and Yield Control in Vegetable Production

THE OPTIMIZATION OF AIR TEMPERATURES FOR GREENHOUSE CUCUMBERS - AN EVALUATION OF DIFFERENT FARMING STRATEGIES

Author:

A. Heissner

Abstract:
From 1985 to 1988 experiments were carried out in a greenhouse consisting of eight individual chambers to examine the impact of different air temperatures on cucumbers. The experiments focused on a method of optimization based on a yield model which allows temperatures to be optimized during 9-d periods over the whole period of yield formation.

The main variants were:

a standard routine with a constant night temperature of 14 °C as a basis for comparison;
an optimized temperature routine based on a fixed outdoor climate (standard climate) (off-line strategy);
an optimized temperature routine based on actual outdoor temperatures (on-line strategy) with and without CO₂-enrichment.

In addition a temperature routine including a decrease in night temperatures from 20 °C down to 11 °C within four weeks after the beginning of the experiment was tested along with a strategy where the mean temperature value fixed for each month had to be approximated as close as possible by way of set-point correction.

The tests were carried out with the cucumber varieties 'Saladin', 'Polo' and 'Stella'. Planting took place between mid and end January.

Full Text (PDF format, 619015 bytes)
Citation

Download Adobe Acrobat Reader (free software to read PDF files)