Sequential infections by 32 isolates of

Context Studies of Phoma black stem and leaf spot disease (caused by medicaginis) in annual medics (Medicago spp.) normally involve a ‘once-only’ inoculation not reflecting multiple pathogen infection phytoestrogen production cycles the field. Phytoestrogen plants can result lower ovulation rates grazing animals. Aims We aimed to determine whether sequential infections P. medicaginis increase phytoestrogens medics, measure genetic diversity isolates. Methods In greenhouse experiment, pathogenicity virulence were investigated across 32 isolates following one, two or three rounds M. polymorpha var. brevispina. Production coumestrol 4′-O-methyl was measured, correlation with parameters assessed. DNA sequencing using ITS, β-tubulin, calmodulin medicaginis-specific EFNI-1α applied for phylogenetic analysis from Western Australia elsewhere. Key results Across isolates, highest incidence 76%, petiole 61%, severity 52% 53%. Stem content range 45–1247 mg kg−1, 0–344 kg−1. All measures after inoculation. Overall, there positive (P < 0.05) both 4′-O-methylcoumestrol 0.01, P 0.05, respectively). Phylogenetic revealed high degree similarity among Australian generally grouping into single separate cluster four markers, genetically distinct sourced outside Australia. Conclusions Leaf best discriminating parameter content. similar unique, possibly due geographic separation. Implications The study emphasised importance inoculations when screening Medicago genotypes towards developing cultivars superior resistance enhanced animal reproductive outcomes.