The EF1α gene was used as a reference for the quantification of Cas gene expression. Primer sequences are listed in the Electronic Supplementary Material (ESM 2). Quantification of the cassiicolin homolog transcripts by real-time

PLX3397 manufacturer RT-PCR Amplifications were performed using an iCycler IQ (Bio-Rad) with SYBR green as the fluorescent dye. The PCR reaction mix (25 μl) contained cDNA (2 μl of a 1/50 dilution of the first strand cDNA), 1× Mesa Green qPCR MasterMix Plus for SYBR Assay W/fluorescein (Eurogentec, Angers, France) and 200 nM of each primer. Polymerase chain reactions were performed as follows: 3 min at 95 °C for denaturation and amplification for 40 cycles (10 s at 95 °C, 15 s at 62 °C, 15 s at 72 °C). The relative quantitative AC220 purchase abundance (Qr) of the Cas homologue transcripts was calculated by comparison with the expression of EF1α using the following formula (Pfaffl 2001), with E representing the primers’ efficiency, “target” referring to the cassiicolin homologues and “ref” to EF1α: $$ \textQr = \frac\left( 1 + \textE_target \right)^\Delta \textCt\,target\left( 1 + \textE_ref \right)^\Delta \textCt\,ref $$The real-time PCR amplifications were performed in triplicate (technical replicates) and the experiment was repeated three times (biological replicates). Data

presented are the mean ± the standard error of the three independent biological replicates. Monitoring of C. cassiicola development

in lesions by real-time RT-PCR To analyze the development of the fungus in the plant tissues, the accumulation of transcripts of the C. cassiicola-specific EF1α gene was monitored and compared to the expression of a polyubiquitin gene from the rubber tree (Hb-polyubiquitin, unpublished results). The primers used to amplify Hb-polyubiquitin transcripts were Hb-Ubi-F/Hb-Ubi-R (ESM 2). The composition of the real-time PCR mix and the check details program used for real-time PCR were the same as described above for the Cas homologues expression analysis, except for the annealing temperature (57 °C). The level of rubber tree colonization by C. cassiicola was represented by the relative expression (Qr) of the fungal EF1α gene Vitamin B12 normalized to the rubber tree Polyubiquitin transcript level. Statistical analyses Analyses of variance (ANOVA) were performed with software R, version 2.10.1 (R_Development_Core_Team 2009) and differences between means were tested using Tukey’s Honest Significant Difference (HSD) test (P < 0.05). For real-time PCR, statistical analyses were performed on log-transformed data because empirical errors in Qr increased with Qr values consistent with the above exponential formulation. Results Diversity of the fungal endophytes A total of 70 endophytic fungi were isolated from asymptomatic rubber tree leaves from a rubber plantation in Bahia, Brazil (ESM 1).