Various strategies are used to reduce postharvest cereal grain contaminants such as insect pests and fungal pathogens. Chemical and physical treatments are common management practices but may leave harmful chemical residues on grains or alter their nutrient content (particularly temperature treatments) and have other limitations. This review explores the recent literature regarding cold plasma, with emphasis on its efficacy for decontamination of postharvest cereal grain from biological contaminants. Cold plasma is an ionised gas containing reactive oxygen and nitrogen species, electrons and free radicals that are lethal to microorganisms and has the potential to decontaminate food surfaces and to increase shelf life. Studies conducted on rice, wheat, corn, barley and oats have demonstrated that cold plasma significantly reduced the amount of fungi, bacteria and their spores on grain surfaces. Cold plasma may also detoxify mycotoxins, and control insect pests. Evidence from various global studies demonstrates the potential use of cold plasma to manage postharvest fungi, mycotoxins and insect pests in Australian stored cereal grain.

A 3-year study evaluated the effect of different seed-priming techniques on the performance of two bread wheat (Triticum aestivum L.) cultivars, Seher-2006 and Shafaq-2006, planted in rows spaced at 22.5 or 30 cm. Three seed priming techniques—on-farm priming, hydropriming, and osmopriming (using CaCl₂)—and an untreated control (dry seeds) were included in the study. Seed priming resulted in earlier and more uniform crop emergence and improved allometric and yield-related traits compared with untreated seeds. Hydropriming and osmopriming significantly improved the allometric traits of Seher-2006 planted at 22.5-cm row spacing and Shafaq-2006 planted at 30-cm row spacing each year. The combination of osmopriming and 30-cm row spacing produced the highest number of productive tillers, number of grains per spike and 1000-grain weight across all experimental years. The highest grain yield and harvest index were recorded for osmopriming and 22.5-cm row spacing each year. Shafaq-2006 produced higher biological yield, whereas Seher-2006 produced the higher grain yield and harvest index. Osmoprimed seeds planted at 22.5-cm row spacing recorded the highest economic returns and benefit : cost ratios in both cultivars. In conclusion, planting osmoprimed seeds of wheat in 22.5-cm spaced rows could be effectively used to increase productivity and economic returns.

In crop studies, shading is a common approach for reducing source activity (i.e. assimilates produced by photosynthesis); however, if source reduction is not directly proportional to the degree of light attenuation, estimations could be flawed. We analysed the effects of shading at three levels on light transmittance, air and canopy temperatures, and actual photosynthetic activity at different times of day, and on grain weight in a modern genotype of bread wheat (Triticum aestivum L.). The treatments were imposed 10 days after anthesis and comprised three levels of shading with meshes: 80%, 50% and 10% transmittance during midday. The decrease in midday photosynthetic activity (electron transport rate, ETR; and CO₂ assimilation, An) in the shading treatments compared with control plants did not fit a 1 : 1 relationship with light transmittance of the meshes; for example, the reduction in ETR and An was <50% under the mesh with 50% light transmittance. The decrease in light transmittance and photosynthesis caused by the meshes was higher during the morning and afternoon than midday. In the grain-filling period, midday ETR showed a progressive, age-dependent decrease in control plants compared with shading treatments. Initial differences in photosynthetic activity between treatments were attenuated throughout the grain-filling period. The diurnal course of air temperature showed a progressive decrease from control to shade treatments, mainly during midday. This pattern was confirmed by infrared thermometry of canopy temperature, with severe shade showing the lowest temperature. Greenness measurements at 19 days after anthesis showed delayed senescence in shaded plants, possibly due to the decrease in temperature under shade. Grain weight per ear was reduced in shading treatments (mainly with 50% and 10% light transmittance). The decrease in grain weight per ear plotted against the decrease in photosynthesis (evaluated through ETR or An) did not fit a 1 : 1 relationship. This could be explained in part by an observed increase in dry matter retranslocation from the stem. In summary, estimations of source reduction on the basis of light attenuation could be biased, because the photosynthesis decrease is less than proportional, and photosynthesis differences are attenuated throughout grain filling.

The gene HvDEP1, on barley (Hordeum vulgare L.) chromosome 5H, encodes a γ-subunit of the heterotrimeric G-protein complex and was previously determined to be a candidate gene underlying a major quantitative trait locus for grain length. In the present study, we identified a 9 bp indel (insertion–deletion mutation) at position –84 bp from the start codon within a reported upstream open reading frame located in the 5′ UTR (untranslated region) and developed a diagnostic molecular marker. We also identified a 13 bp indel (–514 bp) in linkage disequilibrium that bridges an important regulatory motif. Using a doubled-haploid population and a barley diversity panel, we were able to show that the effects of these indels were environmentally stable and consistently delineated phenotypic groups based on grain length and 1000-grain weight. Genotypes represented by deletions at these two positions relative to the reference cv. Morex had consistently shorter grains, by 3.69–3.96%, and lower 1000-grain weight, by 2.38–4.21%, in a doubled-haploid population studied. Additionally, a diversity panel was tested but consistent differences were observed only for grain length, reinforcing literature indicating the importance of this gene for grain-length regulation. The frequency of the longer and heavier grained reference allele was higher in modern cultivars, suggesting that indirect selection for longer grain may have occurred through direct selection for grain yield via grain-weight improvement. These results indicate that grain length and 1000-grain weight in barley can be manipulated by targeting variation in gene promoters through marker-assisted selection.

Common buckwheat (Fagopyrum esculentum Moench) is a valuable crop plant with cereal-like seed chemical composition; however, it is susceptible to thermal stress. The aim of the study was to determine whether heat-shock proteins HSP-90 and HSP-70 can protect common buckwheat against thermal stress during development of microspores and embryo sacs. The study was performed on two accessions of common buckwheat, Panda and PA15, which differed in their tolerance to thermal stress. Accumulation of these proteins was determined in buds, open and wilted flowers, and donor leaves of plants grown at 20°C (control) and 30°C (thermal stress). Photochemical efficiency of donor leaves, closest to the inflorescences, based on chlorophyll a fluorescence (ChlF) was also analysed. All plants demonstrated higher values of ChlF at 30°C than at 20°C, which suggests that this 30°C temperature is more conducive to their vegetative growth. Pollen grains of both accessions demonstrated normal development at 30°C, whereas embryo sacs showed many developmental disturbances. Panda was more sensitive to thermal stress than PA15, as manifested in a higher percentage of degenerated embryo sacs at the flower bud phase. Moreover, a decrease in both HSPs in the studied organs of Panda was found relative to the control. At 30°C, both accessions accumulated more HSP-70 than HSP-90. These results suggest that, under heat stress, HSP-70 plays a protective role for flowers of common buckwheat. The analyses indicated that the donor leaf closest to the flower cluster may be a reliable indicator of temperature sensitivity in buckwheat flowers.

Grass pea (Lathyrus sativus L.) is an important food crop cultivated in dryland agricultural ecosystem. It is an important source of dietary protein to millions of people living in low-income countries in South-east Asia and Africa. The present study emphasises the development of genomic resources and their application in marker–trait association for plant phenology and yield-related traits in lathyrus. In silico mining of nucleotide sequences identified 203 simple sequence repeat (SSR) motifs, of which trimer repeats (62%) were most abundant followed by tetramer (19%), hexamer (10%), pentamer (6%) and dimer (3%) nucleotide repeats. Of 150 SSR markers screened, 60 markers were amplified 75 alleles from 50 germplasm lines with 2–3 alleles per locus and the polymorphic information content of 0.45 was observed. We report 6 significant marker–trait associations using the developed SSR markers for plant phenology and yield-related traits following mixed linear model (Q+K) analysis. Gene ontology search of trait linked markers revealed marker regions encoding genes related to homeobox-leucine zipper protein ATHB-6-like, rubredoxin family protein, and cationic peroxidise. Understanding the association of novel alleles in trait expression will play a significant role in future lathyrus crop improvement programmes.

Grass species grown in South American natural grasslands present different growth strategies related to variations in specific leaf area (SLA), leaf dry matter content (LDMC) and possible nitrogen (N) allocation. Nitrogen fertilisation can have effects on physiological processes such as CO₂ assimilation; however, these responses can change depending on the growth strategy adopted by each species. The aim of the present study is to determine the effects of N fertilisation on SLA, LDMC and CO₂ assimilation in eight C₄ grass species: Axonopus affinis, Paspalum pumilum, P. notatum, P. urvillei, P. plicatulum, Andropogon lateralis, Saccharum angustifolium and Aristida laevis. These species were cultivated in pots filled with soil subjected to two conditions of N availability: nil (control) and 200 mg N kg^–1 soil. The SLA of Axonopus affinis was 5.4 times higher than that of Aristida laevis. Axonopus affinis and P. pumilum recorded the lowest LDMC, their leaves showed 53% lower LDMC than observed for Aristida laevis, on average. Resource-capture species showed variation in leaf area with N addition to values 20% higher than the control, whereas species characterised by a resource-conservation growth strategy recorded variation in leaf area with N addition to values only 8% higher than the control. With N addition, the CO₂ assimilation of resource-capture species represented variation (increase) nine times that of resource-conservation species compared with their respective controls. Resource-capture species have greater CO₂ capture potential than resource-conservation species, mainly a result of N addition.

Plant growth is often constrained by low availability of water and phosphorus (P) in soils in arid and semi-arid areas. Aeolian sandy soils cover >90% of the sandy area of the Mu Us Sandy Land (MUSL) in Northwest China. These soils have low water- and nutrient-retention capacity, limiting their ability to support plant growth. Pisha sandstone, a type of loose rock widely distributed in the MUSL, is regarded as an environmental hazard because it easily weathers, resulting in severe soil erosion and water loss. However, the retention capacity of the aeolian sandy soil can be significantly improved through blending with Pisha sandstone. We investigated the impacts of water supply (35% and 70% of soil water-holding capacity) and P supply (0, 5 and 20 mg P kg^–1 soil) on plant growth and P and nitrogen (N) nutrition by growing lucerne (Medicago sativa L.) in MUSL aeolian sandy soil amended or not with Pisha sandstone. Soil type and P supply had greater effects than water supply on lucerne growth and on P and N nutrition. Biomass accumulation and shoot P and N concentrations were increased by amending the aeolian sandy soil with Pisha sandstone and increasing P supply. The N : P ratios in shoots indicated that plant growth was limited by P but not by N. Aeolian sandy soil amended with Pisha sandstone and supplied with P at 5 mg kg^–1 enhanced lucerne growth; this practice is feasible for pasture development in the MUSL.