Samenvatting

Many people on Earth are hungry or do not have a reliable source of drinking water. Drought-tolerantcrops do not need much water to grow and therefor usable in regions where water is an issue. Cropbreeders are working on crops that are more drought-tolerant and grow faster.

Corp breeders are also working on the resistance against deceases, so expensive pesticides are not needed.To check if the plants are more resistance against deceases the genotype of the plants will be compared.To compare the genotype, parameters are needed such as the root length and the branching angles. Thisresearch will add an additional parameter to this list called the optical attenuation coefficient. The opti-cal attenuation coefficient will be measured with an optical coherence tomography device, because it hasa high resolution and is fast to use.

The optical attenuation coefficient will be determined with the use of two method: the curve fittingmethod and the depth resolved method. Before the optical attenuation coefficient can be determined,the intensity must be corrected for the roll-off effect and the confocal effect. This effect occur due to thelimitations in the OCT device. This resulted in a ratio of spectral resolution to the sampling interval of0.99±0.04.

To control the methods for computing the correct optical attenuation coefficient, a reference measurementon Intralipid has taken place. Both methods resulted in an optical attenuation coefficient a bit lowerthan expected. Still the methods where correct in order of magnitude, therefore they were applied on anArabidopsisleaf from the office. This resulted in an optical attenuation coefficient of theArabidopsisleafof 9.815±1.7 mm−1.