Effect of Light-emitting Diodes, Ultraviolet-B, and Fluorescent Supplemental Greenhouse Lights on Strawberry Plant Growth and Response to Infection by the Anthracnose Pathogen Colletotrichum gloeosporioides

Supplemental lighting is frequently used to extend daylength for strawberries ( Fragaria × ananassa ) grown in greenhouses and high tunnels; however, information limited on the effect of these lights disease development. We evaluated ambient light six supplemental treatments [red, blue, white light-emitting diodes (LEDs), separately; a combination red, LEDs; wide-spectrum fluorescent (WSF); WFS + ultraviolet B (UV-B)] plant growth response greenhouse. Plants were exposed 17 h each day. In WSF+UV-B treatment, plants WSF during day UV-B 3 hours night. Two trials conducted; trial contained five or cultivars was replicated three times. Twice trial, detached leaves from cultivar treatment inoculated with conidial suspension anthracnose crown rot pathogen, Colletotrichum gloeosporioides rated severity 10 days later. There significant difference due relative chlorophyll content parameters. Plant injury ratings lowest LED, WSF, treatments. LED red received higher injury, lower vigor scores, values than all other After inoculation strawberry C. Trial 1, there (DSRs) after 18 weeks’ exposure DSRs being those except treatment. not 24 weeks 1 4 22 2. effects both trials: ‘Strawberry Festival’, ‘Pelican’, ‘Seascape’ DSRs. This study showed an several parameters, including harmful high-intensity irradiation.