Recalculating growth and defense strategies under competition: Key roles of photoreceptors and jasmonates.
Ballare, C. L. and Austin, A. T.
IFEVA, Consejo Nacional de Investigaciones Cientificas y Tecnicas - Facultad de Agronomia, Universidad de Buenos Aires, Av.. San Martin 4453, C1417DSE, Buenos Aires, Argentina.
IIB-INTECH, Consejo Nacional de Investigaciones Cientificas y Tecnicas-Universidad Nacional de San Martin, B1650HMP Buenos Aires, Argentina.
The growth-defense tradeoff in plant biology has gained enormous traction in the last two decades, highlighting the importance of understanding how plants deal with two of the greatest challenges for their survival and reproduction. It has been well-established that in response to competition signals perceived by informational photoreceptors, shade-intolerant plants typically activate the shade avoidance syndrome (SAS). In turn, in response to signals of biotic attack, plants activate a suite of defense responses, many of which are directed to minimize the loss of plant tissue to the attacking agent (broadly defined, the defense syndrome, DS). We argue that components of the SAS, including increased elongation, apical dominance, reduced leaf mass per area (LMA) and allocation to roots, are in direct conflict with configurational changes that plants require to maximize defense. We hypothesize that these configurational tradeoffs provide a functional explanation for the suppression of components of the DS in response to competition cues. Based on this premise, we discuss recent advances in the understanding of the mechanisms by which informational photoreceptors, by interacting with jasmonic acid (JA) signaling, help the plant to make intelligent allocation and developmental decisions that optimize its configuration in complex biotic contexts.
J Exp Bot 70(13): 3425-3434 (2019)