Pest and disease management by red light

Abstract

Light is essential for plant life. It provides a source of energy through photosynthesis and regulates plant growth and development and other cellular processes, such as by controlling the endogenous circadian clock. Light intensity, quality, duration and timing are all important determinants of plant responses, especially to biotic stress. Red light can positively influence plant defence mechanisms against different pathogens, but the molecular mechanism behind this phenomenon is not fully understood. Therefore, we reviewed the impact of red light on plant biotic stress responses against viruses, bacteria, fungi and nematodes, with a focus on the physiological effects of red light treatment and hormonal crosstalk under biotic stress in plants. We found evidence suggesting that exposing plants to red light increases levels of salicylic acid (SA) and induces SA signalling mediating the production of reactive oxygen species, with substantial differences between species and plant organs. Such changes in SA levels could be vital for plants to survive infections. Therefore, the application of red light provides a multidimensional aspect to developing innovative and environmentally friendly approaches to plant and crop disease management.

The Photoperiod: Handling and Causing Stress in Plants

“…LEDs can also be used for pest management. Several studies showed the influence of the light environment in greenhouses (including the length of the photoperiod and light quality) (for review, see Gallé et al, 2021 ; Lazzarin et al, 2021 ), on plant resilience against pathogens such as B. cinerea in strawberries ( Meng et al, 2020 ) or tomatoes ( Yang et al, 2015 ). Understanding how supplemental light through LEDs acts on plant growth and defense may lead to novel sustainable horticultural methods for pest management.…”

Light-Engineering Technology for Enhancing Plant Disease Resistance

“…Tremendous reports demonstrated the essential roles of a certain spectrum of light in promoting plant defense against pathogen infection and herbivore infestation. Normally, red light increases plant resistance to various pathogens, herbivores, and nematodes ( Yang et al, 2018b ; Gallé et al, 2021 ), although the molecular mechanisms were still obscure. As described above, plant innate immunity is an essential strategy deployed by plants to counter invaders.…”

“…Among the various phytohormones, SA, jasmonic acid (JA), and ethylene (ET) are widely reported to be resistant to biotic stresses. Generally speaking, SA is usually considered as a primary hormone against biotrophic, hemibiotrophic pathogens, and phloem-feeding insects; JA and ET mainly regulate plant immune responses against chewing insects and necrotrophic pathogens ( Lazebnik et al, 2014 ; Li et al, 2019 ; Gallé et al, 2021 ). Understanding how plants coordinate phytohormone signaling to counteract serious external threats makes great sense for exploring novel disease resistance strategies.…”

“…Due to the destructive effects of pesticides on the environment, biological and physical strategies for insect control will be very helpful for sustainable agriculture. Rapidly developed greenhouse agriculture has tried to supplement LED lighting systems to optimize crop production and quality, which provides a breakthrough and profound prospect for pest and disease controlling in a light-engineering technology ( Gallé et al, 2021 ; Lazzarin et al, 2021 ). Therefore, it makes great sense for exploring the effects and mechanisms of light-mediated resistance to fight against herbivores.…”

“…The outspreading diseases caused by insect-transmitted plant viruses in the past decades have been mainly driven by planthoppers, whiteflies, aphids, and thrips ( Dáder et al, 2015 ; Wu and Ye, 2020 ). Besides chemical measures, both the biological and physical strategies, such as light quality and quantity, have recently been highlighted for controlling plant viral diseases ( Montes and Pagán, 2019 ; Zhai et al, 2020 ; Gallé et al, 2021 ).…”