DOI: 10.5061/dryad.0rxwdbs7n
title: Data from: Far red light increases maize volatile emissions in response to volatile cues from neighboring plants

description: Plants perceive the presence and defense status of their neighbors through
 light and volatile cues, but how plants integrate both stimuli is poorly
 understood. We investigated if and how low Red to Far red light (R:FR)
 ratios, indicative of shading or canopy closure, affect maize (Zea mays)
 responses to herbivore-induced plant volatiles (HIPVs), including the
 green leaf volatile (Z)-3-hexenyl acetate. We modulated light signaling
 and perception by using FR supplementation and a phyB1phyB2 mutant, and we
 determined volatile release as a response readout. To gain mechanistic
 insights, we examined expression of volatile biosynthesis genes, hormone
 accumulation, and photosynthesis. Exposure to a full blend of HIPVs or
 (Z)-3-hexenyl acetate induced maize volatile release. Short-term FR
 supplementation increased this response. In contrast, prolonged FR
 supplementation or constitutive phytochrome B inactivation in phyB1phyB2
 plants showed the opposite response. Short-term FR supplementation
 enhanced photosynthesis and stomatal conductance and (Z)-3-hexenyl
 acetate-induced JA-Ile levels. We conclude that a FR-enriched light
 environment can prompt maize plants to respond more strongly to HIPVs
 emitted by neighbors, which might be explained by changes in
 photosynthetic processes and phytochrome B signaling. Our findings reveal
 interactive responses to light and volatile cues with potentially
 important consequences for plant-plant and plant-herbivore interactions.
description: # Data from: Far-red light increases maize volatile emissions in response
 to volatile cues from neighboring plants
 [https://doi.org/10.5061/dryad.0rxwdbs7n](https://doi.org/10.5061/dryad.0rxwdbs7n) ## Data & File overview: 1. Excel file containing 27 excel sheets corresponding to the data used in the main and supplemental figures of the manuscript: 1. **Figure 1b.** Volatiles collected and measured by PTR-TOF-MS from both emitter and receiver maize plants. * Number of variables: 12 * Variable list: 1. Emitter = Low Red to Far Red treated plant infested with *S. littoralis* (Low R:FR infested) or left uninfested (Low R:FR non_infested) 2. Receiver = Low or high R:FR treated plant (LowR_FR and HighR_FR) 3. Iteration = volatile sampling iteration 4. Plant = Identification number for each plant that is sampled in the time series analysis. 5. Indole (signal intensity/ grams of fresh weight) 6. Monoterpenes (signal intensity/ grams of fresh weight) 7. Sesquiterpenes (signal intensity/ grams of fresh weight) 8. DMNT = (E)-4,8-dimethyl-1,3,7-nonatriene (signal intensity/ grams of fresh weight) 9. TMTT = (E,E)-4,8,12-trimethyltrideca-1,3,7,11 tetraene: (signal intensity/ grams of fresh weight) 10. Hexenal (signal intensity/ grams of fresh weight) 11. Hexenol (signal intensity/ grams of fresh weight) 12. HexenylAcetate (signal intensity/ grams of fresh weight) 2. **Figure 2b.** Volatiles collected and measured by PTR-TOF-MS from maize plants exposed to low or high R:FR, followed by  (Z)-3-hexenyl acetate and simulated herbivory. * Volatile emissions collected during 2 phases: (I) Exposure to hac and (II) Priming. After hac pre-treatment and simulated herbivory. * Number of variables: 11 * Variable list: 1. Light treatment = low or high R:FR (LowR:FR or HighR:FR) 2. Volatile_treatment = clean air or hac [(Z)-3-hexenyl acetate]. 3. Pre-treatment = pre-exposure to clean air or hac [(Z)-3-hexenyl acetate] for 6 h before Herbivory treatment. 4. SimulatedHerbivory: all plants were induced with wounding and oral secretions from *S. littoralis *(SimulatedHerbivory) 5. Iteration = volatile sampling iteration 6. Plant = Identification number for each plant that is sampled in the time series analysis. 7. Indole (signal intensity/ grams of fresh weight) 8. Monoterpenes (signal intensity/ grams of fresh weight) 9. Sesquiterpenes (signal intensity/ grams of fresh weight) 10. DMNT = (E)-4,8-dimethyl-1,3,7-nonatriene (signal intensity/ grams of fresh weight) 11. TMTT = (E,E)-4,8,12-trimethyltrideca-1,3,7,11 tetraene (signal intensity/ grams of fresh weight) 3. **Figure 3b.** Hormone levels in low and high R:FR treated plants during (Z)-3-hexenyl acetate exposure * Number of variables: 8 * Variable list: 1. Light treatment = Low or High R:FR treatments (Low R_FR or High R_FR) 2. Volatile treatment = clean air or HAC [(Z)-3-hexenyl acetate]. 3. Time_after_exposure_to_HAC (min): 45, 90 and 180 minutes after the start of HAC exposure. 4. OPDA: 12-oxo-phytodienoic acid (ng/grams of fresh weight) 5. JA: jasmonic acid (ng/grams of fresh weight) 6. JA_Ille: jasmonic acid isoleucine (ng/grams of fresh weight) 7. ABA: abscisic acid (ng/grams of fresh weight) 8. SA: salycilic acid (ng/grams of fresh weight) 4. **Figure 3c.** Hormone levels in low and high R:FR treated plants pre-treated with hac or clean air and induction with simulated herbivory * Number of variables: 9 * Variable list: 1. Light Treatment = Low or High R:FR treatments (Low R_FR or High R_FR) 2. Pre-treatment = pre-exposure to clean air or HAC [(Z)-3-hexenyl acetate] for 6 h. 3. SimulatedHerbivory: all plants were induced with wounding and oral secretions from *S. littoralis *(SimulatedHerbivory) 4. Time_after_Simulated_Herbivory (min): 0, 45, 90 and 180 minutes after the induction with simulated herbivory. 5. OPDA: 12-oxo-phytodienoic acid(ng/grams of fresh weight) 6. JA: jasmonic acid (ng/grams of fresh weight) 7. JA_Ille: jasmonic acid isoleucine(ng/grams of fresh weight) 8. ABA: abscisic acid (ng/grams of fresh weight) 9. SA: salycilic acid (ng/grams of fresh weight) 5. **Figure 4b.** Gene expression levels low and high R:FR treated plants during (Z)-3-hexenyl acetate exposure * Number of variables: 8 * Variable list: 1. Light_treatment = Low or High R:FR treatments (Low R:FR or High R:FR) 2. Volatile treatment = clean air or HAC [(Z)-3-hexenyl acetate]. 3. Time_after_exposure_to_HAC (min): 45, 90 and 180 minutes after the start of HAC exposure. 4. TPS2: *Terpene synthase 2* (Normalized expression) 5. TPS10: *Terpene synthase 10* (Normalized expression) 6. CYP92C5: *P450 Monooxygenase CYP92C5 *(Normalized expression) 7. TPS1: *Terpene synthase 1* (Normalized expression) 8. FPPS3: *farnesyl pyrophosphate synthase 3* (Normalized expression) 6. **Figure 4c**. Gene expression levels in low and high R:FR treated plants pre-treated with hac or clean air and induction with simulated herbivory * Number of variables: 9 * Variable list: 1. Light treatment = Low or High R:FR treatments (Low R:FR or High R:FR) 2. Pre-treatment = pre-exposure to clean air or hac [(Z)-3-hexenyl acetate] for 6 h. 3. SimulatedHerbivory: all plants were induced with wounding and oral secretions from *S. littoralis *(Simulated_Herbivory) 4. Time_after_Simulated_Herbivory (min): 0, 45, 90 and 180 minutes after the induction with simulated herbivory. 5. TPS2: Terpene synthase 2 (Normalized expression) 6. TPS10: Terpene synthase 10 (Normalized expression) 7. CYP92C5: *P450 Monooxygenase CYP92C5 *(Normalized expression) 8. TPS1: Terpene synthase 1 (Normalized expression) 9. FPPS3: farnesyl pyrophosphate synthase 3 (Normalized expression) 7. **Figure 5b.** * Number of variables: 4 * Variable list: 1. Light treatment = Low or High R:FR treatments (Low R_FR or High R_FR) 2. Volatile Treatment = clean air or hac [(Z)-3-hexenyl acetate]. 3. Leaf: Leaf 3 from the bottom (L3) 4. StomatalConductance (mmol/m2/s1) 8. **Figure 5c** * Number of variables: 4 * Variable list: 1. Light treatment = Low or High R:FR treatments (Low R_FR or High R_FR) 2. Volatile Treatment = clean air or hac [(Z)-3-hexenyl acetate]. 3. Leaf: Leaf 2 from the bottom (L2) 4. StomatalConductance (mmol/m2/s1) 9. **Figure 5d** * Number of variables: 5 * Variable list: 1. Light treatment = Low or High R:FR treatments (Low R_FR or High R_FR) 2. Volatile Pre-Treatment = clean air or hac [(Z)-3-hexenyl acetate] for 6 h before Simulate Herbivory 3. Simulated Herbivory: Not wounded (NotW) or induced with wounding and oral secretions from *S. littoralis *(wounded) 4. Leaf: Leaf 3 from the bottom (L3) 5. StomatalConductance (mmol/m2/s1) 10. **Figure 5e** * Number of variables: 5 * Variable list: 1. Light treatment = Low or High R:FR treatments (Low R_FR or High R_FR) 2. Volatile Pre-Treatment = clean air or hac [(Z)-3-hexenyl acetate] for 6 h before Simulate Herbivory 3. Simulated Herbivory: Not wounded (NotW) or induced with wounding and oral secretions from *S. littoralis *(wounded) 4. Leaf: Leaf 2 from the bottom (L2) 5. StomatalConductance (mmol/m2/s1) 11. **Figure 6bc.** * Number of variables: 4 * Variable list: 1. Light treatment = Low or High R:FR treatments (Low R_FR or High R_FR) 2. Volatile Treatment = clean air or hac [(Z)-3-hexenyl acetate] for 6 h. 3. Net photosynthesis in leaf 2 (µmol CO2 m-2s-1) 4. Net photosynthesis in leaf 3 (µmol CO2 m-2s-1) 12. **Figure 7b** Volatiles collected and measured by PTR-TOF-MS from maize W22 and PhyB1B2 mutant plants exposed to high R:FR, followed by  (Z)-3-hexenyl acetate and simulated herbivory. * Volatile emissions collected during 2 phases: 1) Exposure to hac and 2) Priming. After hac pre-treatment and simulated herbivory. * Number of variables: 12 * Variable list: 1. Light treatment = low or high R:FR (LowR:FR or HighR:FR) 2. Volatile treatment = clean air or hac [(Z)-3-hexenyl acetate]. 3. Pre-treatment = pre-exposure to clean air or hac [(Z)-3-hexenyl acetate] for 6 h before SimulatedHerbivory. 4. SimulatedHerbivory: all plants were induced with wounding and oral secretions from *S. littoralis *(SimulatedHerbivory) 5. Genotype: W22 or PhyB (PhyB1B2 mutant) 6. Iteration = volatile sampling iteration 7. Plant = Identification number for each plant that is sampled in the time series analysis. 8. Indole (signal intensity/ grams of fresh weight) 9. Monoterpenes (signal intensity/ grams of fresh weight) 10. Sesquiterpenes (signal intensity/ grams of fresh weight) 11. DMNT = (E)-4,8-dimethyl-1,3,7-nonatriene (signal intensity/ grams of fresh weight) 12. TMTT = (E,E)-4,8,12-trimethyltrideca-1,3,7,11 tetraene (signal intensity/ grams of fresh weight) 13. **Figure 8b.** Volatiles collected and measured by PTR-TOF-MS from maize W22 exposed to high R:FR for 6 days or low R:FR for 4 or 6 days, followed by  (Z)-3-hexenyl acetate and simulated herbivory. * Volatile emissions collected during 2 phases: 1) Exposure to hac and 2) Priming: After hac pre-treatment and simulated herbivory. * Number of variables: 11 * Variable list: 1. Light treatment = plants under High Red to Far Red (High R:FR)ratio for 6 days (Low R:FR 6 d), low R:FR for 2 days (Low R:FR 2 d) and low R:FR for 6 days (Low R:FR 6 d). 2. Volatile treatment = clean air or hac [(Z)-3-hexenyl acetate]. 3. Pre-treatment = pre-exposure to clean air or hac [(Z)-3-hexenyl acetate] for 6 h before SimulatedHerbivory. 4. SimulatedHerbivory: all plants were induced with wounding and oral secretions from *S. littoralis *(SimulatedHerbivory) 5. Iteration = volatile sampling iteration 6. Plant = Identification number for each plant that is sampled in the time series analysis. 7. Indole (signal intensity/ grams of fresh weight) 8. Monoterpenes (signal intensity/ grams of fresh weight) 9. Sesquiterpenes (signal intensity/ grams of fresh weight) 10. DMNT = (E)-4,8-dimethyl-1,3,7-nonatriene (signal intensity/ grams of fresh weight) 11. TMTT = (E,E)-4,8,12-trimethyltrideca-1,3,7,11 tetraene (signal intensity/ grams of fresh weight) 14. **Figure S1**. Light spectral conditions under high and low R:FR. * PPFD for each wavelength between 350-800 nm 15. **Figure S2b.** Length of the second internode measured before and after 2 d of low or high R:FR treatments * Number of variables: 3 * List of variables: 1. Light: low or high R:FR (LowR_FR or HighR_FR) 2. Days after the start of the light treatment: at the start of the light treatment (Day0) or after 2 days (Day2). 3. Length of the second internode (cm) 16. Figure S2c. Auxin levels * Number of variables: 2 * List of variables: * Light: low or high R:FR * Auxin (IAA) levels in ng/g FW 17. **Figure S3.** Aboveground biomass of maize plants * Number of variables: 3 * List of variables: 1. Emitter: (1) low R:FR treated plant infested with *S. littoralis *and (Low R:FR infested) (2) low R:FR treated plants without herbivore (Low R:FR non-infested) 2. Receiver: (1) low R:FR treated plant (Low R_FR) or (2) high R:FR treated plant (High R_FR). 3. Emitters Aboveground biomass (g): biomass of stem and leaves of the emitter plants. 18. **Figure S4b**. Volatile emissions measured by PTR-TOF-MS on low and high R:FR treated plants induced with herbivory or left intact. * Number of variables: 9 * List of variables: 1. LightTreatment: low or high R:FR 2. SimulatedHerbivory: (1) notWounded or (2) Wounded + application of oral secretions of *s. litorallis. *(W+OS S. littoralis). 3. Iteration = volatile sampling iteration 4. Plant = Identification number for each plant that is sampled in the time series analysis. 5. Indole (signal intensity/ grams of fresh weight) 6. Monoterpenes (signal intensity/ grams of fresh weight) 7. Sesquiterpenes (signal intensity/ grams of fresh weight) 8. DMNT = (E)-4,8-dimethyl-1,3,7-nonatriene (signal intensity/ grams of fresh weight) 9. TMTT = (E,E)-4,8,12-trimethyltrideca-1,3,7,11 tetraene (signal intensity/ grams of fresh weight) 19. **Figure S5.** Volatiles collected and measured by PTR-TOF-MS from 30 day-old maize plants exposed to low or high R:FR, followed by  (Z)-3-hexenyl acetate and simulated herbivory. * Volatile emissions collected during 2 phases: (1) Exposure to hac and (2) Priming. After hac pre-treatment and simulated herbivory. * Number of variables: 11 * List of variables: 1. Light treatment = low or high R:FR (LowR_FR or HighR_FR) 2. Volatile treatment = clean air or hac [(Z)-3-hexenyl acetate]. 3. Pre-treatment = pre-exposure to clean air or hac [(Z)-3-hexenyl acetate] for 6 h before SimulatedHerbivory. 4. SimulatedHerbivory: all plants were induced with wounding and oral secretions from *S. littoralis *(SimulatedHerbivory) 5. Iteration = volatile sampling iteration 6. Plant = Identification number for each plant that is sampled in the time series analysis. 7. Indole (signal intensity/ grams of fresh weight) 8. Monoterpenes (signal intensity/ grams of fresh weight) 9. Sesquiterpenes (signal intensity/ grams of fresh weight) 10. DMNT = (E)-4,8-dimethyl-1,3,7-nonatriene (signal intensity/ grams of fresh weight) 11. TMTT = (E,E)-4,8,12-trimethyltrideca-1,3,7,11 tetraene (signal intensity/ grams of fresh weight) 20. \**Figure S6. **PTR-MS-TOF analysis of different volatile signatures at different time points after HAC exposure in low and high R:FR treated plants. * Number of variables: 8 * Variable list: 1. Light treatment = low or high R:FR (LowR_FR or HighR_FR) for 2 days 2. Volatile treatment = HAC [(Z)-3-hexenyl acetate]. 3. PAR level: Photosynthetically active radiation (µmol m-2s-1). 4. Indole (signal intensity/ grams of fresh weight) measurement at 180 min after the start of hac exposure. 5. Monoterpenes (signal intensity/ grams of fresh weight) measurement at 360 min after the start of hac exposure. 6. Sesquiterpenes (signal intensity/ grams of fresh weight) measurement at 360 min after the start of hac exposure. 7. DMNT = (E)-4,8-dimethyl-1,3,7-nonatriene (signal intensity/ grams of fresh weight) measurement at 135 min after the start of hac exposure. 8. TMTT = (E,E)-4,8,12-trimethyltrideca-1,3,7,11 tetraene (signal intensity/ grams of fresh weight) measurement at 315 min after the start of hac exposure. 21. \**Figure S7b. **Volatile emissions are measured by using superQ traps and GC-MS. * Volatile emissions collected during 2 phases: (1) Exposure to hac and (2) Priming. After hac pre-treatment and simulated herbivory. * Number of variables: 14 * Variable list: 1. Light treatment = low or high R:FR (LowR_FR or HighR_FR) for 2 days 2. Volatile treatment = Volatile treatment = clean air or hac [(Z)-3-hexenyl acetate]. 3. EndOfSamplingPeriodAfterVolatileExposure= the sampling period finished at 2, 4, and 6 h after the start of hac exposure. 4. EndOfSamplingPeriodAfterHerbivory = the sampling period finished at 2, 4, and 6 h after the start of simulated herbivory. 5. Plant = Identification number for each plant that is sampled in the time series analysis. 6. Pre-treatment = pre-exposure to clean air or hac [(Z)-3-hexenyl acetate] for 6 h before SimulatedHerbivory. 7. SimulatedHerbivory: all plants were induced with wounding and oral secretions from *S. littoralis *(SimulatedHerbivory) 8. alpha_Pinene = α-pinene (signal intensity/ grams of fresh weight) 9. beta_ocimene = β -ocimene  (signal intensity/ grams of fresh weight) 10. Linalool (signal intensity/ grams of fresh weight) 11. dmnt = (E)-4,8-dimethyl-1,3,7-nonatriene (signal intensity/ grams of fresh weight) 12. indole (signal intensity/ grams of fresh weight) 13. Cis_bergamotene = (E)-α-bergamotene (signal intensity/ grams of fresh weight) 14. Farnesene = (*E*)-β-farnesene (signal intensity/ grams of fresh weight) 22. \**Figure S8. **PTR-TOF-MS analysis of pure linalool * Number of variables: 3 * Variable list: 1. Iteration: Number of measurements in time 2. Linalool_Signal_Intensity (AU) 3. MonoterpenesSignalIntensity (AU) 23. \**Figure S9bc **Stomatal density in leaf 2 and 3 after light and hac treatments * Number of variables: 4 * Variable list: 1. Light treatment = low or high R:FR (LowR:FR or HighR:FR) for 2 days 2. Volatile treatment = clean air or hac [(Z)-3-hexenyl acetate] for 3 h. 3. StomatalDensity leaf #3: Number of stomata per mm2 4. StomatalDensity leaf #2: Number of stomata per mm2 24. \**Figure S10. **Growth of WT and *PhyB1B2 *mutant under low or high R:FR treatments * Number of variables: 5 * Variable list: 1. Genotype: phyb1phyb2 mutant or w22 2. Light treatment = low or high R:FR (LowR:FR or HighR:FR) for 2 days 3. Volatile treatment = clean air or hac [(Z)-3-hexenyl acetate] for 3 h. 4. Day_after_start_light_Treatment: when the light treatment started (day 0) and 2 days (day 2) after the start of the light treatment. 5. SecondInternode: Length of the second internode in cm           25. \**Figure S11b **Volatiles collected and measured by PTR-TOF-MS from W22 maize plants exposed to low or high R:FR, followed by  (Z)-3-hexenyl acetate and simulated herbivory. * Volatile emissions collected during 2 phases: (1) Exposure to hac and (2) Priming. After hac pre-treatment and simulated herbivory. * Number of variables: 12 * Variable list: 1. Genotype: All plants are W22. 2. Light treatment = low or high R:FR (LowR:FR or HighR:FR) 3. Volatile treatment = clean air or hac [(Z)-3-hexenyl acetate]. 4. Pre-treatment = pre-exposure to clean air or hac [(Z)-3-hexenyl acetate] for 6 h before SimulatedHerbivory. 5. SimulatedHerbivory: all plants were induced with wounding and oral secretions from *S. littoralis *(SimulatedHerbivory) 6. Iteration = volatile sampling iteration 7. Plant = Identification number for each plant that is sampled in the time series analysis. 8. Indole (signal intensity/ grams of fresh weight) 9. Monoterpenes (signal intensity/ grams of fresh weight) 10. Sesquiterpenes (signal intensity/ grams of fresh weight) 11. DMNT = (E)-4,8-dimethyl-1,3,7-nonatriene (signal intensity/ grams of fresh weight) 12. TMTT = (E,E)-4,8,12-trimethyltrideca-1,3,7,11 tetraene (signal intensity/ grams of fresh weight) 26. **Figure S12b**. Volatiles collected and measured by PTR-TOF-MS from PhyB1B2 (phyb1phyb2) mutant maize plants exposed to low or high R:FR, followed by  (Z)-3-hexenyl acetate and simulated herbivory. * Volatile emissions collected during 2 phases: (1) Exposure to hac and (2) Priming. After hac pre-treatment and simulated herbivory. * Number of variables: 12 * Variable list: 1. Genotype: All phyb1phyb2 mutant plants. 2. Light treatment = low or high R:FR (LowR:FR or HighR:FR) 3. Volatile treatment = clean air or hac [(Z)-3-hexenyl acetate]. 4. Pre-treatment = pre-exposure to clean air or hac [(Z)-3-hexenyl acetate] for 6 h before SimulatedHerbivory. 5. SimulatedHerbivory: all plants were induced with wounding and oral secretions from *S. littoralis *(SimulatedHerbivory) 6. Iteration = volatile sampling iteration 7. Plant = Identification number for each plant that is sampled in the time series analysis. 8. Indole (signal intensity/ grams of fresh weight) 9. Monoterpenes (signal intensity/ grams of fresh weight) 10. Sesquiterpenes (signal intensity/ grams of fresh weight) 11. DMNT = (E)-4,8-dimethyl-1,3,7-nonatriene (signal intensity/ grams of fresh weight) 12. TMTT = (E,E)-4,8,12-trimethyltrideca-1,3,7,11 tetraene (signal intensity/ grams of fresh weight)