Exploring growth-defense tradeoffs in Arabidopsis. Phytochrome B inactivation requires JAZ10 to suppress plant immunity but not to trigger shade avoidance responses

CERRUDO IGNACIO; CALIRI ORTIZ ME; KELER MERCEDES M.; DEGANO M.E.; DEMKURA PATRICIA V; BALLARÉ CARLOS L.

PLANT, CELL AND ENVIRONMENT (PRINT)

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2017

0140-7791

Under conditions that involve a high risk of competition for light among neighboring plants, shade-intolerant species often display increased shoot elongation and greater susceptibility to pathogens and herbivores. The functional links between morphological and defense responses to crowding are not well understood. In Arabidopsis, the protein JAZ10 is thought to play a key role connecting the inactivation of the photoreceptor phytochrome B (phyB), which takes place under competition for light, with the repression of jasmonate-mediated plant defenses. Here we show that a null mutation of the JAZ10 gene in Arabidopsis did not affect plant growth nor did it suppress the shade-avoidance responses elicited by phyB inactivation. However, the jaz10 mutation restored many of the defense traits that are missing in the phyB mutant, including the ability to express robust responses to jasmonate and to accumulate indolic glucosinolates. Furthermore, the jaz10phyB double mutant showed a significantly increased resistance to the pathogenic fungus Botrytis cinerea compared with the phyB parental line. Our results demonstrate that, by inactivating JAZ10, it is possible to partially uncouple shade avoidance from defense suppression in Arabidopsis. These findings may provide clues to improve plant resistance to pathogens in crops that are planted at high density.