**2.2. RNA extraction and quantification of gene expression by real-time PCR**

SA and water-infiltrated wheat leaves were sampled at 3, 6, 9, 12, 15, 18, 21, 24, 48, 72 and 96 hours after infiltration (hai) and stored at -80oC until use. Total RNA was extracted from 100 mg plant tissue using RNeasy Plant Mini Kit (Quiagen, The Netherlands) with some modifications of the protocol. cDNA synthesis was carried out using High Capacity cDNA Reverse Transcription Kit (Applied Biosystems, USA) according to the manufacturer's protocol. Real Time qPCR was performed using ABI Prism 7300 detection system (Applied Biosystems, USA). The *tub* and *ef1α* genes, encoding respectively for tubulin and elongation factor ef1alpha, were used as reference genes. The relative expression of the target genes was evaluated in SA-infiltrated wheat leaves compared with water-infiltrated leaves and normalized to the *tub* and *ef1a* expression level. The analyses were performed using the relative expression software tool REST® as described in [47]. The experiments were repeated twice with similar results and representative results are presented.

#### **2.3. LOX assay**

LOX was assayed as described in [10] according to [48] and [49] with slight modifications. The results are the mean of three biological repetitions.

#### **2.4. Fatty acid extraction and analysis**

Total cellular FAs extraction and purification were performed by the authors in [46] using adapted protocols from [50]. The results are means of three independent repetitions.

Free FAs, PLFA and PL extraction was carried out according to the method described in [51]. Data shown are the results of the first experiment, which need to be confirmed by a biological repetition.
