Downy mildew is a serious threat to opium poppy production globally. In recent years, two pathogen species, Peronospora somniferi and Peronospora meconopsidis, which induce distinct symptoms, have been confirmed in Australia. In order to manage the spread of these pathogens, identifying the sources of inoculum is essential. In this study, we assessed pathogen presence associated with poppy seed. We developed PCR and qPCR assays targeting the coxI and coxII gene regions, for the detection, differentiation, and quantification of P. somniferi and P. meconopsidis in poppy seed. These results were complemented and compared with direct seed histological examination and a seed washing combined with viability staining for oospore detection. The majority of seed lots from all harvest years contained detectable P. meconopsidis, the earliest (1987) predating the first official record of the disease in Tasmania (1996). In contrast, only seed lots harvested in 2012 or later contained P. somniferi, evidence of its more recent introduction. P. meconopsidis contamination was estimated to be as high as 33.04 pg DNA/g of seed and P. somniferi as high as 35.17 pg DNA/g of seed. Incidence of pathogen contamination of seeds, estimated via a group testing protocol, ranged from 0 to 9% (P. meconopsidis) or 0 to 11% (P. somniferi). Mycelia were predominately found external to the seed coat. Seed washing and viability staining demonstrated that putatively viable oospores were present in the majority of seed lots. Transmission testing confirmed both pathogens can be successfully transmitted from infested seed to infected seedling. PCR and qPCR pathogen assays were found to be reliable and offer a routine test for determining pathogen inoculum in poppy seeds.

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Soil salinity is one of the major constraints to crop production worldwide. The multifaceted nature of salinity tolerance traits complicates plant screening and the identification of salt‐tolerant germplasm to be used for the genetic advancement of corps. Many screening criteria have been suggested to distinguish between genotypes. Most of these were applied under controlled environmental conditions and limited to one developmental stage of plants. As a result, most of the reported tolerance could not be validated under field conditions. This study employed a membership function value (MFV) to assess NaCl tolerance of eight wheat (Triticum aestivum) genotypes measured at germination, vegetative and reproductive stages, as an integrative tool for the overall plant performance. Salt stresses had an adverse effect on plant physiological (residual transpiration, stomatal density, chlorophyll fluorescence characteristics; leaf N, Na+ and K+ content) and agronomical (plant height; biomass; root and tiller number; grain) characteristics. Based on this assessment, plants were divided into three contrasting groups: salt tolerant, moderately salt tolerant and salt sensitive. Although genotypes did not show the same degree of tolerance in germination, glasshouse and field experiments, the variety Yu‐07 showed consistently better performance in all trials, whilst Aus19720 was most sensitive in glasshouse and field experiments. These contrasting genotypes could be of a potential value for further studies to uncover the genetic mechanisms governing salt stress response in wheat.