PT  - JOURNAL ARTICLE
AU  - Dominik Schneider
AU  - Laura S. Lopez
AU  - Meng Li
AU  - Joseph D. Crawford
AU  - Helmut Kirchhoff
AU  - Hans-Henning Kunz
TI  - Dynamic light experiments and semi-automated plant phenotyping enabled by self-built growth racks and simple upgrades to the IMAGING-PAM
AID  - 10.1101/795476
DP  - 2019 Jan 01
TA  - bioRxiv
PG  - 795476
4099  - http://biorxiv.org/content/early/2019/10/07/795476.short
4100  - http://biorxiv.org/content/early/2019/10/07/795476.full
AB  - Background Over the last years, several plant science labs have started to employ fluctuating growth light conditions to simulate natural light regimes more closely. Under fluctuating light, many plant mutants previously described as phenotype-free under standard constant light have started to reveal quantifiable effects. Moreover, many subtle plant phenotypes become intensified and thus can be studied in more detail. This observation has caused a paradigm shift within the photosynthesis research community and an increasing number of scientists are interested in using dynamic growth light conditions. However, high installation costs for controllable LED setups as well as costly phenotyping equipment make it hard for small academic groups to compete in this emerging field.Results We show a simple do-it-yourself approach using off-the-shelf parts to enable dynamic light growth experiments. Our results using previously published fluctuating light sensitive mutants, stn7 and pgr5, confirm that our low-cost setup yields similar results as top-prized commercial growth regimes. Moreover, we show how to reconfigure a standard Walz IMAGING-PAM, found in many departments around the world, into a medium throughput phenotyping platform. We have designed a Python and R-based open source toolkit that allows for semi-automated sample segmentation and data analysis thereby reducing the processing bottleneck of large experimental datasets. We provide detailed instructions on how to build and functionally test each setup.Conclusions With material costs well below $1000, it is possible to setup a fluctuating light rack including a constant light control shelf for comparison. This allows more scientists to perform experiments closer to natural light conditions and contribute to an emerging research field. A small addition to the IMAGING-PAM not only increases sample throughput but also enables larger-scale plant phenotyping with automated data analysis.