Development and Evaluation of a Prototype of Shape-Adaptable and Portable All-Digital PET System for In-Lab and In-Field Plant Imaging

Positron emission tomography (PET) is increasingly employed for precision monitoring in plant science, as it is a noninvasive technique for the quantitative analysis of the functional mechanisms of plant metabolism. When exported to digital agronomy in combination with qualitative detection, PET has the potential to drive the sustainable management of chemical fertilizers. Such a translational approach requires a transition from controlled in-lab to natural in-field PET imaging. We report a novel portable and shape-adaptable digital plant PET system based on the multivoltage threshold (MVT) digital readout, with an extendable transverse field of view (FOV) ranging between 80 and 120 mm. The system reaches a peak sensitivity up to
${(16.94\pm 0.01)}$
% and
${(9.12\pm 0.01)}$
% in closed and maximally opened FOV configuration, respectively. Image quality has been tested with dedicated plant phantom imaging. We verified the ability of the prototype to perform plant PET imaging: in-lab with Zea mays L. sprouts under heat stress and in-field with Triticum aestivum sprouts under drougt stress.