EFFECTS OF DECREASING VPD BY MISTING ON LEAF AREA AND LEAF INCLINATION IN TOMATO AND ESTIMATION OF CONSEQUENCES ON LIGHT ABSORPTION

During summer, in the Mediterranean regions, the yield of glasshouse tomatoes declines.
The present experiment aimed to determine whether severe climatic conditions during this period of the year are responsible for this drop.
The effects of reducing VPD in tomato were studied on leaf area from July to September and spatial leaf distribution and leaf angle distribution were determined in September.
Plant leaf area in July was less than in September due to lower unitary leaf area.
Misting increased leaf area and fruit yield in July, but had no effect in September.
In September, misting favoured a heterogeneous distribution of leaf inclination, but differences in spatial distribution and orientation of leaves had no effect on light absorption.
We discussed the effect of misting on leaf area with contradictory results reported in the bibliography.
Further measurements of plant architecture when the effects on VPD are maximal (in July) are necessary to conclude on the effects of VPD on estimated light absorption.

III International Workshop on Models for Plant Growth and Control of the Shoot and Root Environments in Greenhouses

H. Gautier, M. Tchamitchian, S. Guichard

leaf area, leaf orientation, light absorption, misting, tomato, water vapour pressure deficit

https://doi.org/10.17660/ActaHortic.1999.507.8