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An open-source LED lamp for use with the LI-6800 photosynthesis system
Aarón I Vélez-Ramírez1,2,3, Juan de Dios Moreno1, Uriel G Pérez-Guerrero1,2
1Laboratorio de Ciencias Agrogenómicas, Escuela Nacional de Estudios Superiores Unidad León Universidad Nacional Autónoma de México Boulevard UNAM 2011 León 37684 Guanajuato Mexico.
Premise:
Controlling light flux density during carbon dioxide assimilation measurements is essential in photosynthesis research. Commercial lamps are expensive and are based on monochromatic light-emitting diodes (LEDs), which deviate significantly in their spectral distribution compared to sunlight.
Methods And Results:
Using LED-emitted white light with a color temperature similar to sunlight, we developed a cost-effective lamp compatible with the LI-6800 Portable Photosynthesis System. When coupled with customized software, the lamp can be controlled via the LI-6800 console by a user or Python scripts. Testing and calibration show that the lamp meets the quality needed to estimate photosynthesis parameters.
Conclusions:
The lamp can be built using a basic electronics lab and a 3D printer. Calibration instructions are supplied and only require equipment commonly available at plant science laboratories. The lamp is a cost-effective alternative to perform photosynthesis research coupled with the popular LI-6800 photosynthesis measuring system.
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