LeasyScan Phenotyping Platform
The past twenty years has seen a revolution in the genomics tools, driven by technology and leading to an increase in knowledge of genetics of more and more crops. There is now a consensus that phenotyping has become the main bottleneck to make use of the huge genomics information.
Technologies have recently developed to escalate the throughput and precision of phenotyping, relying mostly on imaging technology (infrared, RGB, NIR, hyperspectral, fluorescence). The start of that “phenomics” revolution has been dominated by a concept called “Plant-to-imaging cabinet” concept (with an overwhelming monopoly of LemnaTec Ltd), with potted plants moved onto conveyor belts, and using mostly 2-D images to infer a volumetric representation of plants to extract biomass and leaf area parameters. A number of these platforms are now installed across the world, with capacity varying between 400 to 1600 plants and a throughput of about 1600 plants/day.
The Focus Now
The focus is now on the use of 3-D images to have a better evaluation of leaf canopy parameters, and of a “camera-to-plant” concept to increase the throughput. The LeasyScan platform is using this emerging concept, using scanners (PlantEye®) that project a laser line at a fixed wavelength on top of the canopy. A camera with a 45 degree angle then captures the reflection of the laser line at a high rate (50-80 pics s-1), allowing the reconstitution of 3-D images. Several algorithms then operate to extract leaf area, leaf angle, plant height, and average leaf area. The scanners measure pre-set areas (called sectors) of 65cm width and either 40cm or 60cm length. A grid of barcodes throughout the platform allows re-setting scanner position in y and z directions. The 8 scanners are mounted on top of an irrigation boom. Their movement at a constant speed and height above the pots has been two of the key considerations during the design of the platform. Each scanner deals with two strips of sectors. At a speed of 3m min-1 in scanning mode and 8 in return mode, the scanner supporting device (SSD) is able to scan the entire platform, i.e. 4800 plots, in two hours.
This platform is a totally new concept with a huge potential. It is meant and designed to be versatile and adaptable to upgrades, additional sensors and plant parameters. It has been developed with clear research questions in mind (essentially to measure leaf area quicker to access the dynamic of leaf development and leaf conductance). However, with the accuracy and throughput of the PlantEye, we expect a degree of serendipity in what the LeasyScan has in store for us.