Imaging techniques in plant physiology: from simple to multispectral approaches

8. 
   Future Perspectives
   
   
   

Tools for predicting the short-term evolution of plant growth parameters based on weather conditions are receiving increasing interest. Simulation approaches (for a review see Room et al., 1996) are used to model transpiration of canopies using virtual plants (Dauzat et al., 2001). The influence of temperature and other environmental factors on transpiration in the field was shown to be reliably predicted by this simulatory approach.

Robotisation of imaging will enable efficient screening of plant populations (Chaerle and Van Der Straeten, 2000). This could be applied to screen for mutants in photosynthetic efficiency (Varotto et al., 2000). As an extension to the current efforts in genome characterisation, imaging techniques could also prove to be useful in the elucidation of the function of unknown genes introduced into transgenic plants (Chaerle and Van Der Straeten, 2001).

Since engineering plants for disease resistance is becoming a reality with the unravelling of the plant genome (Stuiver and Custers, 2001), imaging could be applied to quantify the temporal and spatial characteristics of increased resistance in transformed plants. By applying this method the most promising transgenic plants could be rapidly selected. Another approach made possible by timely detection of (a)biotic stresses by imaging, would consist in switching on engineered stress resistance genes with environment-friendly inducers, which are either volatile or can be applied as a liquid spray (Pickett and Poppy, 2001; Mittler and Rizhsky, 2000).

9. 
   Conclusions
   
   
   

With the currently available imaging detector technology and portable computing power, (multispectral) monitoring solutions will likely be incorporated into management strategies for plant breeding and ultimately crop production. Such mobile systems could provide an early warning system. Subsequently other measuring techniques need to be used to verify the obtained indications. Fast characterisation of emerging stress has the potential to increase both quality and productivity of agricultural crops.

Acknowledgements

We thank M. De Cock for layout. This research was supported by grants from the Fund for Scientific Research (Flanders) (G0068.90, G0021.92, G.0023.95N, 1.5.514.98 and G0015-01).

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