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Integrated Pest Management (IPM) offers a suite of ways by which to reduce the need for pesticide use, thus minimising environmental damage and pathogen resistance build-up in crop production. Farmers and agronomists active in the Scottish spring barley sector were surveyed to determine the extent to which they currently use or are open to implementing three IPM measures – varietal disease resistance, crop rotation, and forecasting disease pressure – in order to control three important fungal diseases. Overall, the survey results demonstrate that farmers and agronomists are open to using the three IPM techniques. However, gaps between actual and perceived recent practice were large: despite over 60% of farmers stating that they sowed varieties highly resistant to Rhynchosporium or Ramularia, less than one third of reportedly sown varieties were highly resistant to these diseases. Similarly, over 80% of farmers indicated that they used crop rotations, yet 66% of farmers also reported sowing consecutive barley often/always. Further research is needed in order to understand why these gaps exist, and how they can be reduced in future in order to increase IPM uptake and optimise pesticide use. [ABSTRACT FROM AUTHOR]

Barley scald caused by Rhynchosporium commune is known as one of the most deleterious diseases on barley all over the world, especially in the Middle East including Iran. Barley genotypes screening against this disease is an efficient way to find the more tolerant pedigrees. For this purpose, a field experiment was designed at Ghamlou station in the Kurdistan province of Iran during 2013 and 2014, and reaction of twenty four lines and commercial cultivars were evaluated under natural inoculums of R. commune. Based on our results, the genotypes had different reactions compared with each other during both years of experiment. Disease severity rate in 2013 was higher than in 2014, while reactions of some genotypes showed a positive correlation. All genotypes in 2014 had higher yield than in 2013. It appears that different reaction of the genotypes during these both years was in association with meteorological fluctuations such as rainfall rate. Finding resistant or tolerant genotypes to scald disease and compatible to specific areas along with their extensive cultivation lead to obtain the most adapted and yielding cultivars. [ABSTRACT FROM AUTHOR]

Rhynchosporium commune (formerly known as Rhynchosporium secalis), the causal agent of scald disease on barley, is known to spread asexually by splash dispersed conidia. However, there are multiple lines of evidence for the possibility of a clandestine sexual cycle occurrence in this species including extensive genotypic diversity, equal distribution of mating type alleles across the world and expression of mating type genes. In the current study, the potential for the occurrence of a sexual cycle amongst the Iranian population of R. commune was assessed by analyzing distribution and frequency of the mating type alleles at both micro and macrospatial scales. A total of 95 single-conidial R. commune isolates were obtained from different barley fields in Kurdistan province. Previously designed primers were applied in a multiplex PCR assay to study distribution and frequency of the mating type alleles within and between populations. Totally, 67 isolates were determined as MAT1-1 and the remaining 28 isolates as MAT1-2 throughout the sampling counties. The results obtained at a macro-spatial scale revealed that unlike Kamyaran county (both MAT1-1 and MAT1-2 at an equal ratio), an unequal distribution of mating type genes was dominant among R. commune isolates in both Mariwan and Dehgolan counties. Our findings support a predominantly asexual reproduction for Mariwan and Dehgolan counties and the possibility of sexual stage occurrence in Kamyarna county. [ABSTRACT FROM AUTHOR]