A literature review was conducted to collate best practice techniques for soil compaction management within cotton-farming systems in Australia. Universally negative effects of traffic-induced soil compaction on the whole-farm system and the wider environment include: (i) increased gap between attainable and potential yields, (ii) increased costs of energy and labour, (iii) reduced fertiliser-use efficiency, (iv) reduced water use efficiency (irrigation and rainfall), (v) increased tillage intensity. Knowledge gaps that merit research priority, and research strategies, are suggested. These include: (i) identifying wider impacts on farm economics to guide decision-making and development of decision support systems that capture the effects of compaction on fertiliser, water, and energy use efficiency; (ii) predicting risks at the field or subfield scale and implementing precision management of traffic compaction; (iii) canopy management at terminal stages of the crop cycle to manipulate soil-moisture deficits before crop harvest, thereby optimising trafficability for harvesting equipment; (iv) the role of controlled traffic farming (CTF) in mitigating greenhouse gas emissions and loss of soil organic carbon, and in enhancing fertiliser and water-use efficiencies; (v) recent developments in tyre technology, such as low ground-pressure tyres, require investigation to assess their cost-effectiveness compared with other available options; and (vi) catchment-scale modelling incorporating changes in arable land-use, such as increased area under CTF coupled with no- or minimum-tillage, and variable rate technology is suggested. Such modelling should assess the potential of CTF and allied technologies to reduce sediment and nutrient losses, and improve water quality in intensively managed arable catchments. Resources must be efficiently managed within increasingly sophisticated farming systems to enable long-term economic viability of cotton production. Agronomic and environmental performance of cotton farming systems could be improved with a few changes, and possibly, at a reasonable cost. Key to managing soil compaction appears to be encouraging increased adoption of CTF. This process may benefit from financial support to growers, such as agri-environmental stewardships, and it would be assisted by product customisation from machinery manufacturers.

The high-molecular-weight glutenin subunits (HMW-GS) represent a major component of the endosperm storage protein in the grains of wheat and its related species. Their technological importance results from their ready formation of intermolecular disulfide bonds, which underlie much of the visco-elasticity displayed by gluten and hence the processing quality of the flour. Here, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis revealed that the Chinese wheat cultivar Xiaoyanmai 7 formed four distinct HMW-GS, two of which are likely the product of a known allele at the Glu-B1 locus, whereas the other two did not match any known HMW-GS. A combined analysis based on reversed-phase high-performance liquid chromatography (RP-HPLC), N-terminal sequencing and mass spectrometry confirmed that the two novel proteins were genuine HMW-GS. Inspection of the DNA sequences showed that one of the novel HMW-GS was encoded by an x-type and the other by a y-type secalin gene. A karyotypic analysis confirmed that six of the seven pairs of Xiaoyanmai 7’s D genome chromosomes (the exception was chromosome 2D) had been replaced by rye chromosomes. The y-type HMW secalin present in Xiaoyanmai 7 differed from the standard By and Dy HWM-GS by the presence of an additional cysteine residue in its C-terminal domain.

Some Spanish barley (Hordeum vulgare L.) landraces perform better than modern cultivars at low-production sites. The objective of this study was to identify favourable quantitative trait loci (QTLs) for interesting agronomic traits contributed by the landrace SBCC073. To achieve this objective, a population of 100 BC₁F₅ lines was derived from the cross between the elite cultivar Orria, with high productivity, and the Spanish landrace SBCC073, which was the best performer in low-production trials. The population was evaluated in field trials for 3 years (2011, 2013, and 2014) in Zaragoza, Spain. The population was genotyped with a DArTseq genotyping-by-sequencing assay. A genetic linkage map was developed by using markers of four flowering-time genes and 1227 single-nucleotide polymorphisms of good quality. The genetic map resulted in 11 linkage groups, covering a total distance of 871.1 cM. Five QTLs for grain yield were detected on 2H.1, 4H, 5H and 6H.2. Alleles from SBCC073 contributed to increased yield in three of them. A region at the end of chromosome 5H contains favourable alleles for early vigour, higher grain yield and earlier flowering, all derived from SBCC073. Alleles from Orria contributed to increasing grain yield and simultaneously to reducing plant height on the same region of 6H.2, and to increasing 1000-kernel weight on chromosomes 3H and 5H.

No-tillage systems associated with intercropping practices of grains and forages as cover crops are increasing in the Cerrado agricultural areas. The aim of this study was to quantify the nitrogen (N) uptake efficiency of maize (Zea mays L.) grown as monoculture and intercropped with tropical forages under a no-tillage system by using the ¹⁵N isotope tracer in conjunction with measurements of soil microbial biomass N and available soil N. The experiment was conducted in the 2010–11 growing season, in a Dystrophic Red-Yellow Latosol (Typic Haplustox) in the Cerrado. The experiment was established in a complete randomised block design with three replicates with the following treatments: maize monoculture; maize intercropped with Panicum maximum Jacq. cv. Aruana; and maize intercropped with Brachiaria humidicola (Rendle) Schweick. Nitrogen was applied as ammonium sulfate at a rate of 100 kg ha^–1 (30 kg N ha^–1 was applied at planting and 70 kg N ha^–1 as a side-dressing). The N-fertiliser uptake efficiency in maize and grain yield was not affected by the presence of the intercropped forages. The intercropped B. humidicola and P. maximum recovered 2.08% and 3.71% of the N fertiliser applied, respectively. The soil was the main N source for maize. Maize intercropped with P. maximum showed higher values of microbial biomass N and available N in the soil.

Improving frost tolerance and winter hardiness with desirable agronomic features are the main objectives in winter faba bean (Vicia faba L.) breeding programs, especially in cool temperate regions of Europe. In this study, 189 single-seed-descent lines of winter faba bean from the Göttingen Winter Bean Population were evaluated in field trials (winter hardiness and yield traits). Seven traits were examined (three winter-hardiness traits and four yield traits) and scored. Of the 189 genotypes, 11 lines were identified as winter hardy and having high seed yield. The highest repeatability (h²) estimates were found for leaf frost susceptibility (0.86) among the winter-hardiness traits and for days to flowering (0.95) among the yield traits. In total, 25 putative quantitative trait loci (QTLs) were identified, for winter survival rate (one QTL), 1000-seed weight (one QTL), field plant height (two QTLs), days to flowering (nine QTLs), and seed yield (12 QTLs), based on the association mapping approach using 156 single nucleotide polymorphism (SNP) markers. Candidate genes were identified for QTLs by using synteny between Vicia faba and Medicago truncatula. The SNP markers identified in this study may be used for accelerating breeding program in faba bean to improve winter hardiness and yield traits.

Pastures sown to lucerne (Medicago sativa L.) with a perennial non-legume could increase feed supply relative to traditional pastures based on subterranean clover (Trifolium subterraneum L.). Such mixtures might also be preferable to pure lucerne pastures, which are prone to weed invasion. Yield and water-use efficiency (harvested dry matter per unit evapotranspiration) of mixtures with lucerne or subterranean clover were compared a field experiment established under rainfed conditions at Hamilton, Victoria. Soil moisture and dry matter production were measured over 2 years. Treatments included chicory (Cichorium intybus L.), cocksfoot (Dactylis glomerata L.) and tall fescue (Festuca arundinacea Shreb.) with either lucerne or subterranean clover; pure lucerne; and phalaris (Phalaris aquatica L.) and perennial ryegrass (Lolium perenne L.) with only subterranean clover. In the second year, dry matter production from lucerne mixtures exceeded that of equivalent mixtures with subterranean clover in spring, summer and winter. In spring, the lucerne component continued producing for longer than the clover component through its use of deeper stored soil water, and in summer, lucerne continued to grow slowly after the grass component had entered a drought-induced dormancy. In winter, the contribution from the lucerne component complemented, rather than competed with, that from the non-legume component. Water-use efficiencies during winter–spring ranged from 4 kg ha^–1 mm^–1 for chicory–clover to 27 kg ha^–1 mm^–1 for a fescue–lucerne mixture, and during summer–autumn from nil for cocksfoot–clover to 13 kg ha^–1 mm^–1 for a fescue–lucerne mixture. This study demonstrates that lucerne-based mixtures can increase forage supply per unit water use relative to traditional pastures based on subterranean clover.

The rediscovery of grey leaf spot (caused by Stemphylium spp.) in narrow-leafed lupins (Lupinus angustifolius L.) in Western Australia in 2007 and identification of susceptible cultivars raised concern about potential impact of this disease in crop production. This study assessed potential yield loss in narrow-leafed lupins and the importance of inoculum source in the development of the disease. In two field experiments, no disease was observed in the resistant cultivar Mandelup, but disease progress was rapid in susceptible genotypes Unicrop and WALAN2333 and resulted in up to 64% yield loss. Disease progress and yield loss were greater in plots inoculated with infested trash than in those with spray-only inoculum. Release of Stemphylium spores from infested trash was monitored during the lupin-growing period by using spore traps and seedling trap plants. Conidia were released continuously throughout the growing period and significant (P < 0.01) correlation was found between the number of conidia captured and the frequency of rain, and between disease severity on trap plants and aerial concentration of conidia. The results confirm that grey leaf spot can severely reduce yield of susceptible narrow-leafed lupin cultivars and that removal or avoidance of previous season trash will be important in preventing spread of the disease.

Bacillus subtilis strain GB03 enhances growth and photosynthesis in the model plant Arabidopsis thaliana and several crop plants. In the present study, the effects of seed soaking with GB03 suspension culture and its volatile organic compounds on seed germination of Codonopsis pilosula (Franch.) Nannf. were investigated, and soil-grown C. pilosula seedlings were assayed to measure growth and photosynthetic capacity after soil inoculation with GB03. Both seed soaking with GB03 suspension culture and the presence of volatile organic compounds enhanced seed germination, especially seed germination vigour. GB03 significantly improved shoot and root length, branching, plant biomass (whole plant fresh and dry weight), leaf area and chlorophyll content in C. pilosula seedlings after 20, 40 and 60 days of soil inoculation. GB03 significantly enhanced transpiration rate, stomatal conductance and net photosynthetic rate, but decreased intercellular CO₂ concentration. This study provides insight for the application of selected bacteria to improve biomass in Chinese herbal crops.

Thermal imaging has been used to evaluate the response to drought and warm temperatures in a collection of Brachypodium distachyon lines adapted to varied environmental conditions. Thermographic records were able to separate lines from contrasting rainfall regimes. Genotypes from dryer environments showed warmer leaves under water deficit, which suggested that decreased evapotranspiration was related to a more intense stomatal closure. When irrigated and under high temperature conditions, drought-adapted lines showed cooler leaves than lines from wetter zones. The consistent, inverse thermographic response of lines to water stress and heat validates the reliability of this method to assess drought tolerance in this model cereal. It additionally supports the hypothesis that stomatal-based mechanisms are involved in natural variation for drought tolerance in Brachypodium. The study further suggests that these mechanisms are not constitutive but likely related to a more efficient closing response to avoid dehydration in adapted genotypes. Higher leaf temperature under water deficit seems a dependable criterion of drought tolerance, not only in B. distachyon but also in the main cereal crops and related grasses where thermography can facilitate high-throughput preliminary screening of tolerant materials.

Spatial variability of leaf nutrients in oil palm (Elaeis guineensis Jacq.) plantations in Goa, Karnataka, Mizoram and Gujarat states of India were examined for implementation of site-specific fertilisation programs. Georeferenced leaf samples were collected randomly for the oil palm plantations. The leaf nutrient concentrations were assessed and analysed statistically and geostatistically. The concentrations of leaf nutrients such as nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S) and boron (B) in oil palm plantations varied widely at different locations. Leaf P concentration was positively and significantly correlated with S concentration at Goa, Karnataka and Gujarat. Positive and significant correlation between leaf Ca and Mg concentration was recorded at Mizoram and Gujarat. Geostatistical analysis of leaf nutrients showed different distribution patterns at different locations. This study revealed the need to determine spatial variability of nutrient status of oil palm plantations before planning a differential fertiliser program. Therefore, saving of nutrients could be achieved by adopting site-specific nutrient-management strategies.

Figure 3 is incorrect because the simulations depicted are not, in fact, based on data obtained in the presence of unlimited nitrogen. The correct figure is presented below. The data shown now match those in Table 4.

The authors apologise for the error.

Fig. 3.  Simulated mean frost–heat-adjusted grain yields of four wheat maturity types sown at 2-week intervals at 13 locations across Australia’s high-rainfall cropping zone. The four maturity types were a slow winter type (●), a fast winter type (○), a medium spring type (■), and a fast spring type (□). Data presented are for a crop density of 150 plants/m² with unlimited N provided throughout crop growth.