ISHS Acta Horticulturae 268: IV International Symposium on CO2 in Protected Cultivation
EFFECTS OF CO2 AND PLANT DENSITY ON GROWTH AND YIELD OF GLASSHOUSE GROWN FREESIAS |
| Author: | J.C. Doorduin |
| Abstract:
It has been demonstrated for many glasshouse crops that increasing the CO2 concentration leads to improved quality and yield, while concentrations below the ambient level lead to loss of quality and yield. Relatively few experimental data are known for freesia in this area and on freesia holdings CO2 enrichment is applied only to a limited extent. For this reason in an experiment 4 CO2 concentrations were combined with 4 plant densities to investigate the effect of CO2 on quality and yield of the cultivar 'Blue Heaven'. The CO2 concentrations realised were 265, 360, 560 and 860 ppm. Plant densities were 57, 78, 100 and 121 corms per net square metre. The concentration of 265 ppm resulted in a 20% lower yield of stems, corms and cormlets and a reduction of stem quality as compared to 360 ppm. Increasing the concentration to 560 ppm resulted in a 20% higher yield and an improved quality as compared to 360 ppm. Levels exceeding 560 ppm did not improve yield and/or quality. Higher plant densities did not give higher yields but evidently reduced quality. Vase life was not affected by differences in CO2 concentrations or plant densities. | |
Download Adobe Acrobat Reader (free software to read PDF files) | |
