Light-dependent molecular links between growth and defense responses

BALLARE CARLOS L

Conferencia; ? IV Simposio en Fitopatología, Universidad San Francisco de Quito; 2019

Light-dependent molecular links between growth and defense responsesCarlos L. BallaréIFEVA and IIB Consejo Nacional de Investigaciones Científicas y Técnicas ? Universidad de Buenos Aires, Ave. San Martín 4453, C1417DSE, Buenos Aires, Argentina and IIB-INTECH, Consejo Nacional de Investigaciones Científicas y Técnicas?Universidad Nacional de San Martín, B1650HMP Buenos Aires, ArgentinaPlants detect and respond to the proximity of competitors using light signals perceived by photoreceptor proteins. A low ratio of red to far-red radiation (R:FR ratio) is a signal of competition that is sensed by phytochrome B (phyB). Low R:FR ratios increase the synthesis of growth-related hormones, including auxin and gibberellins. phyB is also an important modulator of hormonal pathways that regulate plant immunity against herbivores and pathogens, including the jasmonic-acid (JA) signaling pathway. Low R:FR ratios down-regulate JA-induced responses. This down-regulation helps the plant to optimize its developmental configuration and resource allocation patterns under conditions of intense competition. In this presentation, I will discuss recent advances in the understanding of the mechanisms that link phyB with JA metabolism, and explore their functional implications. Unveiling the molecular links between photoreceptors and the regulators of plant immunity is important to understand how plants deal with resource allocation tradeoffs under natural conditions. This knowledge can provide a functional platform for breeding and management strategies aimed at improving plant health in cultivated species.