Dualex Leaf clip Sensor

All plants require a ready supply of macro and micronutrients and Nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), sulphur (S), magnesium (Mg) and iron (Fe) are all essential if they are to thrive. 

Deficiencies in any of these nutrients can be visible as a reduction in leaf chlorophyll content and a depletion in overall leaf chlorophyll content limits the plant’s photosynthesis capabilities and production.

Measuring the chlorophyll content of the plant’s leaves can not only provide growers with important nutritional information, but it can also help to identify stress factors; it can pinpoint issues such as pigment inhibiting herbicide damage; and above all, it can provide valuable insights into plant growth and yield potential, allowing targeted and optimised nutrient fertilisation strategies to be developed.

By measuring chlorophyll growers have been able to improve yield and reduce the amount of fertiliser required.

Traditionally, chlorophyll content has been measured in labs by extracting the chlorophyll itself from a leaf sample – a time-consuming process. The Dualex leaf clip sensor, however, has been developed by optical instrument manufacturer FORCE-A, to measure chlorophyll, flavonols and anthocyanins in leaves in a quick and non-destructive way.

Dualex measures the chlorophyll by analysing the light transmitted through the leaf, providing users with a µg/cm² reading from 5-80 µg/cm². 

This unique sensor has also been developed to measure flavonols, which are mainly synthesised after light exposure and are therefore a good indicator of plant-light interaction history, by analysing the screening effect on chlorophyll fluorescence. Flavonols and anthocyanins content are given in relative absorbance units, 0 to 3 for flavonols and 0 to 1.5 for anthocyanins.

After several years of research and experimentation, it has been discovered that polyphenols, specifically flavonols, are also a good indicator of the nitrogen status of plants. The Dualex’s NBI® (Nitrogen Balance Index) combines chlorophyll and flavonols (related to nitrogen/Carbon allocation) and is less sensitive to the variations of environmental conditions than the chlorophyll such as leaf age and thickness.


  • Clipping the leaf with Dualex doesn’t cause any damage.
  • It’s fast and simple – one measurement takes less than one second.
  • Dualex measures automatically after leaf detection.
  • Lightweight and compact
  • Dualex has a wide sampling area of 5mm diameter.
  • The 8cm long clip allows users to measure the middle of the leaf where chlorophyll is less variable and more representative.
  • Growers will also be pleased to note that the Dualex also records additional information such as date, time and GPS position.