Hormonal root to shoot signalling in JA deficient plants Carlos de Ollas Ian Dodd
Seventh framework Programme Food, Agriculture and Fisheries, Biotechnology Contract # 289365 Root to shoot signalling of single and multiple abiotic stresses
Grafting: the surgical alternative to breeding Vigour Airborne diseases Environmental conditions Resource capture Resource use efficiency Scion Phenotypic variability G x E S x E Crop Productivity & Quality Graft union R x S R x S x E Xylem Phloem Soilborne diseases Resource uptake PGPR and mycorrhizae (AMF) Soil physical properties Soil chemical properties Water nutrients hormones proteins RNA DNA Rootstock R x E Rootstock-Scion communication
www.rootopower.eu WP1 GENETICS AND PHYSIOLOGY OF ROOTSTOCK-INDUCED RESISTANCE TO ABIOTIC STRESSES WP2 VALIDATION AND RESOLUTION OF QTLS WP3 GENETICS AND PHYSIOLOGY OF RHIZOSPHERE BIOTA-INDUCED RESISTANCE TO ABIOTIC STRESSES WP4 GENETICS AND PHYSIOLOGY OF INTEGRATED ROOTSTOCK X BIOTA INDUCED RESISTANCE TO MULTIPLE AND COMBINED ABIOTIC STRESSES WP5 ROOTSTOCK X BIOTA INDUCED YIELD STABILITY IN FIELD MULTISTRESS CONDITIONS: A PROOF OF CONCEPT WP6 IDENTIFICATION OF ROOT SIGNALING PROCESSES INVOLVED IN RHIZOSPHERE- INDUCED CROP RESISTANCE TO INDIVIDUAL AND COMBINED ABIOTIC STRESSES WP7 Dissemination and IPR WP8 Coordination and Management ROOTOPOWER: understanding the power of root traits to alleviate edaphic stresses
Different phytohormones and ions detected with varying success Al, As, Be, Bi, B, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, Pb, P Sb, Se, S, Sr, Ti, Tl, V, Zn 12 1 Frequency of Detection (%) 8 6 4 2 ACC tz ZR ip GA1 GA3 GA4 IAA ABA JA SA B Ca Cu Fe K Mn Mg Na P S Zn
Introduction Jasmonic acid Involved in developmental cues: Fruit ripening Production of viable pollen Root growth Involved in stress responses: Defense from herbivores Plant resistance to insects and pathogens Wounding
WT/WT WT/JL5 JL5/JL5 JL5/WT Reciprocal grafted plants JL5 jasmonic acid deficient tomato plants Does JA deficiency affects in any way plants tolerance to water stress or it s response to water stress? Is there any difference in stomatal conductance and transpiration in water stress conditions? According to bibliography JA is able to induce stomatal closure so a diminished stomatal response would be predictable. Does ABA accumulation in roots and shoots in response to stress will differ due to JA absence? Does JA moves between roots and shoots and viceversa? Root produced JA is able too move to the leaves trough the xylem?
Plastid LOX AOS AOC α-linolenic acid 13(S)-HPOD 12,13(S)-EOT MeJA=JA? OPDA? GPA1 PLDα PA jai1 ABA abi1/abi2 OST1(SnRK)2 ost1 RBOH ROS NO Leaf apoplast Guard cell Peroxisome OPR OPDA [Ca 2+ ]cyt slac β-oxidation 3X OPC-8: K + in K + out Ca 2+ Anion channel JA GORK SLAC JAR Increased ψ H 2 O efflux = stomatal closure Cytosol JA-Ile Increased K leaf PIP ψ leaf? ABA systemic
Root-to-shoot jasmonic acid signalling under water deficit WT(scion)/WT (rootstock) WT(scion)/JL5 (rootstock) JL5 (scion)/jl5 (rootstock) JL5 (scion)/wt (rootstock) Shoot specific impact of jasmonates (stomata) Root specific impact of jasmonates (L) Root-to-shoot impact (hormone, hydraulic)?
Evapotranspiration (ml/cm 2 ).6.5.4.3.2.1. a b bc c WT/WT WT/JL5 JL5/WT JL5/JL5 2WAY ANOVA Scion P=.52 Root P =.65 S x R P=.356 GRAFT COMBINATION
8 Soil moisture vs gs WT / WT WT / JL5 JL5 / WT JL5 / JL5 Scion P<.1 Moisture P<.1 gs (mmol / m 2 s) 6 4 2 2 4 6 8 Soil moisture (ms)
JA deficient scion defines whole plant behaviour despite the rootstock Soil moisture vs gs 8 JL5 / WT JL5 / JL5 6 5 JL5/JL5 JL5/WT 4 gs (mmol / m 2 s) 6 4 gs (mmol/m 2 s) 3 2 1 2 2 4 6 8 Soil moisture (ms) 2WAY ANOVA Rootstock P=.546 Soil moisture P <.1 Rootstock x SM P=.511-1 -.9 -.8 -.7 -.6 -.5 -.4 -.3 -.2 -.1 LWP (MPa) 2WAY ANOVA Rootstock P=.69 LWP P =.6 Rootstock x LWP P=.75
WT scion defines whole plant behaviour BUT rootstock seems to be able to influence scions sensitivity Soil moisture vs gs 1 8 WT / WT WT / JL5 8 WT/WT WT/JL5 gs (mmol / m 2 s) 6 4 gs (mmol/m 2 s) 6 4 2 2 2 4 6 8 Soil moisture (ms) 2WAY ANOVA Rootstock P=.993 Soil moisture P <.1 Rootstock x SM P=.79-2 -1.4-1.2-1. -.8 -.6 -.4 -.2. LWP (MPa) 2WAY ANOVA Rootstock P=.3 LWP P <.1 Rootstock x LWP P=.57
ROOT HYDRAULIC CONDUCTIVITY L (g H 2 O cm -2 Root Area Bar -1 min -1 ) 25 2 15 1 5 a b a b Rootstock determines L despite scion WT/WT WT/JL5 JL5/WT JL5/JL5 GRAFT COMBINATION
Hormone concentration in leaves 2WAY ANOVA Scion P=.4 Root P =.235 S x R P=.72 OPDA (ng/g D.W) 3 25 2 15 1 5 OPDA in leaves (Water stress) c b a GRAFT COMBINATION (SCION/ROOTSTOCK) a WT/WT WT/JL5 JL5/JL5 JL5/WT 2WAY ANOVA Scion P=.1 Root P =.71 S x R P=.694 Plastid LOX AOS AOC α-linolenic acid 13(S)-HPOD 12,13(S)-EOT ABA (ng/g D.W) 1 8 6 4 2 ABA in leaves (Water stress) b a WT/WT WT/JL5 JL5/JL5 JL5/WT GRAFT COMBINATION (SCION/ROOTSTOCK) c c JA (ng/g D.W) 18 16 14 12 1 8 6 4 2 JA in leaves (Water stress) a ab b a WT/WT WT/JL5 JL5/JL5 JL5/WT GRAFT COMBINATION (SCION/ROOTSTOCK) 2WAY ANOVA Scion P=.169 Root P =.78 S x R P=.11 Peroxisome OPR β-oxidation 3X JAR Cytosol OPDA OPC-8: JA JA-Ile
ABA and JAIle in xylem sap.35 ABA delivery in Xylem sap.4 JAILe delivery in Xylem sap.3 WELL WATERED WATER STRESS WELL WATERED WATER STRESS ABA (ng L -1 s -1 ).25.2.15.1 JAILe (ng L -1 s -1 ).3.2.1.5. WT/WT WT/JL5. WT/WT WT/JL5 GRAFT COMBINATION (SCION / ROOTSTOCK) GRAFT COMBINATION (SCION / ROOTSTOCK).35 ABA delivery in Xylem sap.4 JAILe delivery in Xylem sap.3 WELL WATERED WATER STRESS WELL WATERED WATER STRESS ABA (ng L -1 s -1 ).25.2.15.1 JAILe (ng L -1 s -1 ).3.2.1.5. JL5/WT JL5/JL5 GRAFT COMBINATION (SCION / ROOTSTOCK). JL5/WT JL5/JL5 GRAFT COMBINATION (SCION / ROOTSTOCK)
Root to shoot signalling Is root sourced JA-JAILe able to influence OPDA biosynthesis in leaves and hence gs? Significant root effect on OPDA accumulation in leaves JA and JA-Ile are xylem mobile signals BUT OPDA is not a sap mobile signal Jasmonates biosynthesis is controlled by product and signal feedback regulation
ACKNOWLEDGEMENTS (includes) Andrew Thompson Ian Dodd Caroline Kemp Carlos de Ollas Anja Dieleman Sevilay Topcu Maria Jose Asins Emilio Carbonell Juan Manuel Ruiz-Lozano Monica Calvo-Polanco Francisco Perez-Alfocea Alfonso Albacete Cristina Martinez Andujar Ascen Martinez Perez Paco Garcia Sanchez Aquilino Sanchez-Bravo Eva Lucic Carolin Schneider Stephan Declerck Katia Plouznikoff