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Peach trees showing witches'‐broom disease symptoms in the northwest of Iran were sampled for phytoplasma detection. PCR assays and Sanger sequence analyses indicated that ʻCandidatus Phytoplasma phoeniciumʼ was associated with peach witchesʼ‐broom disease. Virtual RFLP analyses of the 16S rRNA gene indicated that ʻCa. Phytoplasma phoeniciumʼ strain, which was prevalent in the northwest of Iran belonged to 16SrIX‐C subgroup. For the genomic characterization of Iranian ʻCa. Phytoplasma phoeniciumʼ strain, total DNA extracted from the infected peach trees was subjected to Illumina next‐generation sequencing. The NGS sequencing resulted in 41157647 read pairs of raw data. The raw reads length was 150 bp and the insert size was 350 bp. Assembly and genes clustering finally resulted in 750 contigs with a total size of 228345 bp. The GC content of sequence was 33.2%, N50 value was 259 and L50 value was 256. According to NCBI‐ PGAP annotation the genome of Prunus persica phytoplasma PP2 contained 410 genes including 377 CDSs with protein, 10 rRNAs, nine tRNAs and 14 pseudogenes. [ABSTRACT FROM AUTHOR]

Genetic diversity and population structure among 29 isolates of Ascochyta rabiei ( AR) obtained from diseased chickpea plants in six different geographical origins in Iran was characterized by MAT and rep- PCR ( BOX/ ERIC/ REP) markers. Both mating types were found in all six populations, and the frequencies of mating types were variable between populations. The majority of the isolates belonged to Mat1-1 (58.12%) with the remainder (41.88%) being Mat1-2. A dendrogram was calculated with Jaccard's similarity coefficients with unweighted pair group method clustering ( UPGMA) for the combination of rep- PCR results, AR strains were differentiated into four clusters (A-D) at 60% similarity level. ERIC, REP and BOX showed a total of 19, 37 and 24 alleles per locus, respectively. Gene diversity (He) and Shannon's information index (I) were the highest in the REP (He = 0.82; I = 2.11), while the lowest values were estimated for the ERIC (He = 0.42; I = 1.3). Our result showed that among the three techniques studied, REP- PCR produced the most complex amplified banding patterns, which reflected a high degree of diversity among the Iranian AR strains. ERIC- PCR was the least discriminating method, and BOX- PCR was intermediate. To the best our knowledge, this is first study of assessment of genetic diversity of AR isolates by rep- PCR markers. [ABSTRACT FROM AUTHOR]