Growth tracking of basil by proximal remote sensing of chlorophyll fluorescence in growth chamber and greenhouse environments
Artikel i vetenskaplig tidskrift, 2016

Remote sensing is a promising tool for plant phenotyping and precision farming, as it allows for non-invasive, fast and automated measurements of relevant plant traits with spatial and temporal resolution. The simplest and most used remote sensing application in the field is to use reflectance vegetation indices, based on the optical properties of chlorophyll, as indicators of variables of interest. However, the applicability is limited by their sensitivity to environmental conditions and canopy structure. Another remotely sensed signal related to chlorophyll is chlorophyll fluorescence. Compared to reflectance it is plant specific and directly linked to plant physiological processes; but it is also weak, which complicates its use for in-field applications. This study evaluates the performance of an active proximal remote sensing system utilizing the chlorophyll fluorescence ratio method, measuring the ratio of red fluorescence to far-red fluorescence (termed SFR), for the assessment of growth and biomass as an alternative or complement to reflectance vegetation indices. Basil plants were subject to chlorophyll fluorescence and weight measurements periodically throughout commercial growth cycles, both in a laboratory and commercial greenhouse environment. In the laboratory, SFR showed a strong linear relationship with dry weight on logarithmic scales. Further characterization of the method indicated that it is independent of background light and the same growth dynamics is obtained irrespective of point in time during chlorophyll fluorescence induction. The same trend that was observed in the laboratory was also observed in the greenhouse, but varying background light from the sun and from supplemental lighting added complexity that needs to be addressed in further studies. To our knowledge, the strong link between SFR and biomass, both in a closed environment and greenhouse setting, has not so clearly been demonstrated on canopy level before. Owing to the simplicity of the method, being relatively cheap and fast, it has potential for commercial applications.

plant physiology

Canopy level

Agriculture

Growth tracking

laser-induced fluorescence

reflectance

Proximal sensing

nitrogen-deficiency

maize

fluorescence

photosynthesis

Biomass estimation

vegetation

leaf

Chlorophyll fluorescence

Computer Science

a

wheat

Författare

Daniel Bånkestad

Torsten Wik

Chalmers, Signaler och system, System- och reglerteknik, Reglerteknik

Computers and Electronics in Agriculture

0168-1699 (ISSN)

Vol. 128 77-86

Ämneskategorier

Ekologi

Atom- och molekylfysik och optik

Annan fysik

DOI

10.1016/j.compag.2016.08.004

Mer information

Skapat

2017-10-08