Optical Marker Developed for Plant Stress

This leaf-clip, the result of 15 years of development by French research institute CNRS, allows to perform real-time and non-destructive measurements.

Sep 7 2011 --- FORCE-A has developed Dualex Scientific, a chlorophyll-meter that also measures flavonols.

This leaf-clip, the result of 15 years of development by French research institute CNRS, allows to perform real-time and non-destructive measurements. Its internal GPS is used for the geolocalization of the blocks.

This optical sensor offers various applications, specifically used in ecophysiology:
•    Detection of nitrogen deficiency (especially nitrogen) and input management.
•    Quality control (wheat protein).
•    Variety selection and phenotyping (low input seedlings) in major and specialised crops.
•    Assessment of thermal stress resistance, UV, light and low temperatures.
•    Test of plant natural protection (natural protection stimulation,elicitors, etc.).
•    Polyphenol antioxydant quantification of leaf and fruit epidermis.
•    Foliar development and plant senescence monitoring.

Basically, Dualex Scientific is a stress marker is used to assess plant health and development.

The indices, calculated by the system, are:

- SFR (Simple Fluorescence Ratio), the chlorophyll content of the sample.
- FLAV, the content of flavonols.
- NBI (Nitrogen Balance Index), ratio SFR/FLAV, marker of nitrogen deficiency and protein rate.

Dualex is named into numerous scientific publications involving various crops:

- Fan, L., Fang, C., Dubé, C., Tremblay, N., Khanizadeh, S. (2011) A non-destructive method to predict polyphenol content in strawberry. Journal of Food, Agriculture & Environment Vol.9, WFL Publisher Science and Technology (2):59-62.
- Tremblay, N., Wang, Z., Cerovic, Z.G. (2011) Sensing crop nitrogen status with fluorescence indicators. A review. Agronomy for Sustainable Development, Official journal of the Institut National de la Recherche Agronomique (INRA).
- Louis, J., Meyer, S., Maunoury-Danger, F., Fresneau, C., Meudec, E., Cerovic, Z.G. (2009) Seasonal changes in optically assessed epidermal phenolic compounds and chlorophyll contents in leaves of sessile oak (Quercus petraea): towards signatures of phenological stage. Functional Plant Biology, 36(8):732-741.
- Meyer, S., Louis, J., Moise, N., Piolot, T., Baudin, X., Cerovic, Z.G. (2009) Developmental changes in spatial distribution of in vivo fluorescence and epidermal UV absorbance over Quercus petraea leaves. Annals of Botany, 104:621-633.
- Cerovic, Z.G., Moise, N., Agati, G., Latouche, G., Ben Ghozlen, N., Meyer, S. (2008) New portable optical sensors for the assessment of winegrape phenolic maturity based on berry fluorescence. J. Food Comp. Anal., 21:650-654.
- Cartelat, A., Cerovic, Z.G., Goulas, Y., Meyer, S., Lelarge, C., Prioul, J.-L., Barbottin, A., Jeuffroy, M.-H., Gate, P., Agati, G. Moya, I. (2005) Optically assessed contents of leaf polyphenolics and chlorophyll as indicators of nitrogen deficiency in wheat (Triticum aestivum L.). Field Crops Research, 91:35-49.