A leafclip optical sensor

Dualex - header

Instant non-destructive nitrate and chlorophyll measurement.

Dualex is a leafclip sensor which measures chlorophyll and polyphenols content of plant leaves.

About Dualex

Thanks to a patented technology, this optical sensor allows simple, fast, and non-destructive measurement of chlorophyll, flavanols and anthocyanins in leaves.
Dualex - box

Accurate measurement of chlorophyll

Chlorophyll plays a vital role in photosynthesis and plant development. Dualex measures the chlorophyll by analyzing the light transmitted through the leaf. Thanks to a chemical calibration made by FORCE-A, the chlorophyll is given in µg/cm² in the range of 5-80 µg/cm².

Unique leafclip sensor to measure flavonols and anthocyanins content in leaves

Flavonols are mainly synthesized after light exposure. As a consequence, they are a good indicator of plant-light interaction history.

Dualex measures flavonols and anthocyanins by analyzing the screening effect of flavonols and anthocyanins on chlorophyll fluorescence. Flavonols and anthocyanins content are given in relative absorbance units from 0 to 3 for flavonols and 0 to 1.5 for anthocyanins.

Dualex measuring

NBI®: Nitrogen balanced index

Chlorophyll is often used as an indicator of plant nitrogen status. Several years of research and experimentation showed that polyphenols, specifically flavonols, are also good indicators of nitrogen status of plants.

NBI® (Nitrogen Balance Index) combines chlorophyll and flavonols (related to nitrogen/Carbon allocation). It’s a nitrogen plant status indicator directly correlated with massic nitrogen content. The NBI® is less sensitive to the variations of environmental conditions than the chlorophyll (leaf age, leaf thickness…).

Technical specifications

Measuring material
Plant leaves
Measuring system
Transmittance and screening effect on chlorophyll fluorescence
Index measured
Chlorophyll (CHL), Flavonols (FLAV), anthocyanins (ANTH), NBI
4,5% for CHL, 3,5% for FLAV and ANTH
1,3% for CHL, 2% for FLAV and ANTH
Area measured
19,6 mm²
Leaf thickness
1.5 mm maximum
Measurement time
< 1 s
User interface
LCD screen, Sound warning
Internal GPS
Relative accuracy
< 2,5 m (CEP, 50%, 24 h static)
Storage capacity
10 000 multiparametric data
Data output
.csv file
Data transfer
Operating temperature
From 5 to 45 °C
Li-ion rechargeable
6 hours
Total weight
220 g
205 x 65 x55 mm

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