Sensors can identify herbicide resistant weeds in fields

Identifying resistance currently requires intensive bioassays in glass houses, enzyme assays or gene sequencing, which take time and are costly. However, analysing the colouration of leaves after being sprayed could be one quick and easy alternative.

Pei Wang, at the University of Hohenheim in Germany, is investigating the use of imaging technology to identify resistant populations of silky bent grass, a particular weed problem in Germany.

Herbicide resistant weeds

Results show that the Weed Pam sensor can detect weeds with a strong resistance to ALS (acetolactate synthase) and PSII (photosynthetic) inhibitor herbicides. “It offers an easier and faster way of detecting resistance, allowing farmers to take action in the same growing season.”

Photo credit: Nigel Cattlin

However, Wang adds that silky bent grass with a low resistance to acetyl coA carboxylase (ACCase) inhibitor herbicides cannot be differentiated from a sensitive population and more work is needed to develop the approach, which may be applied to other weeds.

Dr Wang was speaking at the recent European Conference on Precision Agriculture, held in Edinburgh.