Greenhouse tomato plants tend to cycle between an overly vegetative and an overly reproductive growth status. In long crop cycles it is important to maintain plants under balance so that production is maintained as uniform as possible. Therefore, knowledge regarding plant growth status in response to environmental conditions is an important tool to predict near-future yield as well as potential near-future losses.
The hypothesis being investigated is that, by manipulating the environmental factors, which affect transpiration, both at the canopy level (potential transpiration, ET0), and at the root level (electrical conductivity, EC), it is possible to change photoassimilate distribution between source [leaves] and sink [fruits] during the fruiting cycle of the crop and steer the plant towards more vegetative or more reproductive growth if desired, as well as achieve and maintain a balance between these two developmental trends. The main goal of this study is to quantify the individual and combined effect of canopy and root environments on certain plant morphological characteristics, which are being used as indicators of plant growth status, and establish a correlation between these morphological characteristics and productivity.
This study will provide useful information regarding greenhouse climate control strategies for greenhouse tomato production in arid regions. Furthermore, once a relationship between plant growth status and yield is established this study will be able to provide the grower with a powerful decision support system, since it would allow for environmental adjustments before yield losses occur. These environmental adjustments can be made directly through the automated environmental control system.