Several species of Heteroptera are responsible for kernel damage in wheat, Triticum aestivum L. (Poaceae), which affects bread-making quality. In Europe, the most noxious bugs belong to the genera Eurygaster (Scutelleridae) and Aelia (Pentatomidae). In the present work, five bug species frequently found in wheat fields in north-western Italy, Eurygaster maura, E. austriaca, Aelia acuminata, Nezara viridula and Carpocoris purpureipennis, were tested in field trials for their capacity to induce wheat damage. The sodium dodecyl sulphate sedimentation volume test was used as the qualitative control. Among the bug species tested, E. maura was the most noxious pest, with C. purpureipennis being almost as noxious as E. maura. In contrast, E. austriaca and A. acuminata, which have been considered the wheat pests of major importance, as well as N. viridula, caused no or only moderate damage to wheat quality. The adoption of an antiserum specifically produced with E. maura salivary glands proved to be effective and specific in detecting bug damage. Therefore, this polyclonal antibody is promising for the development of a reliable test for the quick evaluation of commercial wheat flour batches.

A field experiment was conducted to quantify changes in soil aggregation and aggregate-associated soil organic carbon (SOC) concentration 1, 3, 5 and 10 years after abandoned, salinized land in the Manasi River Basin was reclaimed for cotton (Gossypium hirsutum L.). Results showed that reclamation significantly increased SOC concentrations and SOC stocks. Specifically, 10 years of cotton production increased SOC concentrations by 45% in the 0–60 cm depth and SOC stocks by 35%. The SOC concentrations and stocks decreased as soil depth increased. Reclamation time, season and soil depth had significant interaction effects on SOC. The SOC concentrations were significantly and positively correlated with available soil nitrogen and available soil phosphorus. Compared with abandoned farmland, macro-aggregate-associated (>250 µm) SOC concentrations in the 0–60 cm depth increased by 47% after 5 years of cotton production and by 53% after 10 years of cotton production. The contribution of macro-aggregate-associated SOC to total SOC in the 0–60 cm depth increased by 87% after 5 years of cotton production and by 69% after 10 years of cotton production. The findings indicate that soil aggregates were more stable after abandoned, salinized farmland was reclaimed for cotton production. Furthermore, cotton production can increase SOC concentrations and sequester C in this arid area.

Conservation agriculture (CA) is inadequately developed for rice-based cropping systems widely practiced in Bangladesh. The current drawback is the implementation of CA for all crops including rice (Oryza sativa L., ecotype ‘transplanted aman’ [T. aman]) to increase rice–wheat (Triticum aestivum L.) rotation productivity. It is important to identify the best combination of tillage types and cropping systems to achieve a high yield of component crops and improve soil health. Three tillage practices, assigned to main experimental plots [namely, zero tillage (ZT), conventional tillage using a rotary tiller (CT) and deep tillage using a chisel plough (DT)] and three different cropping systems, assigned to sub-plots [namely, WFT: wheat–fallow–T. aman, WMT: wheat–mungbean (Vigna radiata L. Wilczek)–T. aman and WDT: wheat–dhaincha (Sesbania rostrata)–T. aman], were tested. After 4 years, ZT under WDT and WMT significantly increased soil organic matter (SOM) at 0–150 mm depth, and these replicates also held the highest levels of total organic carbon. Soil organic carbon (C) increased at a rate of 1.17 and 1.14 t/ha/y in ZT under WDT and WMT, respectively, while CT and DT under WFT were almost unchanged. After 4 years, SOM build-up by the three-crop system (WDT and WMT) under ZT helped conserve soil moisture and improve other soil properties, such as reduction in soil strength and bulk density and increase plant available water content, thus maintaining an optimum soil water infiltration rate. Zero tillage under WMT and WDT showed significant improvements in root mass density of rice and wheat at increased soil depth. The WDT and WMT plots under DT consistently gave the highest yield followed by WDT and WMT under CT, in contrast with ZT under WMT or WDT, which showed the highest improvement in crop yields over the years. In summary, minimum soil disturbance together with incorporation of a legume/green manure crop into the rice–wheat system as well as the retention of their residues increased soil C status, improved soil properties and maximized grain yields.

Maize in Canada is grown mainly in the south-eastern part of the country. No comprehensive studies on Canadian maize yield levels have been done so far to analyse the barriers of obtaining optimal yields associated with cultivar, environmental stress and agronomic management practices. The objective of the current study was to use a modelling approach to analyse the gaps between actual and potential (determined by cultivar, solar radiation and temperature without any other stresses) maize yields in Eastern Canada. The CSM–CERES–Maize model in DSSAT v4·6 was calibrated and evaluated with measured data of seven cultivars under different nitrogen (N) rates across four sites. The model was then used to simulate grain yield levels defined as: yield potential (YP), water-limited (YW, rainfed), and water- and N-limited yields with N rates 80 kg/ha (YW, N-80N) and 160 kg/ha (YW, N-160N). The options were assessed to further increase grain yield by analysing the yield gaps related to water and N deficiencies. The CSM–CERES–Maize model simulated the grain yields in the experiments well with normalized root-mean-squared errors <0·20. The model was able to capture yield variations associated with varying N rates, cultivar, soil type and inter-annual climate variability. The seven calibrated cultivars used in the experiments were divided into three grades according to their simulated YP: low, medium and high. The simulation results for the 30-year period from 1981 to 2010 showed that the average YP was 15 000 kg/ha for cultivars with high yield potential. The YP is generally about 6000 kg/ha greater than the actual yield (YA) at each experimental site in Eastern Canada. Two-thirds of this gap between YP and YA is probably associated with water stress, as a gap of approximately 4000 kg/ha between the YW and the YP was simulated. This gap may be reduced through crop management, such as introducing irrigation to improve the distribution of available water during the growing season. The simulated yields indicated a gap of about 3000 and 1000 kg/ha between YW and YW,N-80N for cultivars with high YP and low YP, respectively. The gap between YW and YW,N-160N decreased to <2000 kg/ha for high Yp cultivars with little difference for the low Yp cultivars. The different yield gaps among cultivars suggest that cultivars with high YP require high N rates but cultivars with low YP may need only low N rates.

Triticale has a reputation for performing well on poor soils, under drought and with reduced inputs, but there has been little investigation of its performance on the better yielding soils dominated by wheat production. The present paper reports 16 field experiments comparing wheat and triticale yield responses to nitrogen (N) fertilizer on high-yielding soils in the UK in harvest years 2009–2014. Each experiment included at least two wheat and at least two triticale varieties, grown at five or six N fertilizer rates from 0 to at least 260 kg N/ha. Linear plus exponential curves were fitted to describe the yield response to N and to calculate economically optimal N rates. Normal type curves with depletion were used to describe protein responses to N. Whole crop samples from selected treatments were taken prior to harvest to measure crop biomass, harvest index, crop N content and yield components. At commercial N rates, mean triticale yield was higher than the mean wheat yield at 13 out of 16 sites; the mean yield advantage of triticale was 0·53 t/ha in the first cereal position and 1·26 t/ha in the second cereal position. Optimal N requirement varied with variety at ten of the 16 sites, but there was no consistent difference between the optimal N rates of wheat and triticale. Triticale grain had lower protein content and lower specific weight than wheat grain. Triticale typically showed higher biomass and straw yields, lower harvest index and higher total N uptake than wheat. Consequently, triticale had higher N uptake efficiency and higher N use efficiency. Based on this study, current N fertilizer recommendations for triticale in the UK are too low, as are national statistics and expectations of triticale yields. The implications of these findings for arable cropping and cereals markets in the UK and Northern Europe are discussed, and the changes which would need to occur to allow triticale to fulfil a role in achieving sustainable intensification are explored.

Australia has a role to play in future global food security as it contributes 0·12 of global wheat exports. How much more can it contribute with current technology and varieties? The present paper seeks to quantify the gap between water-limited yield potential (Yw) and farmer yields (Ya) for wheat in Australia by implementing a new protocol developed by the Global Yield Gap and Water Productivity Atlas (GYGA) project. Results of past Australian yield gap studies are difficult to compare with studies in other countries because they were conducted using a variety of methods and at a range of scales. The GYGA project protocols were designed to facilitate comparisons among countries through the application of a consistent yet flexible methodology. This is the first implementation of GYGA protocols in a country with the high spatial and temporal climatic variability that exists in Australia.

The present paper describes the application of the GYGA protocol to the whole Australian grain zone to derive estimates of rainfed wheat yield gap. The Australian grain zone was partitioned into six key agro-climatic zones (CZs) defined by the GYGA Extrapolation Domain (GYGA-ED) zonation scheme. A total of 22 Reference Weather Stations (RWS) were selected, distributed among the CZs to represent the entire Australian grain zone. The Agricultural Production Systems sIMulator (APSIM) Wheat crop model was used to simulate Yw of wheat crops for major soil types at each RWS from 1996 to 2010. Wheat varieties, agronomy and distribution of wheat cropping were held constant over the 15-year period. Locally representative dominant soils were selected for each RWS and generic sowing rules were specified based on local expertise. Actual yield (Ya) data were sourced from national agricultural data sets. To upscale Ya and Yw values from RWS to CZs and then to national scale, values were weighted according to the area of winter cereal cropping within RWS buffer zones. The national yield gap (Yg = Yw–Ya) and relative yield (Y% = 100 × Ya/Yw) were then calculated from the weighted values.

The present study found that the national Yg was 2·0 tonnes (t)/ha and Y% was 47%. The analysis was extended to consider factors contributing to the yield gap. It was revealed that the RWS 15-year average Ya and Yw were strongly correlated (R 2 = 0·76) and that RWS with higher Yw had higher Yg. Despite variable seasonal conditions, Y% was relatively stable over the 15 years. For the 22 RWS, average Yg correlated positively and strongly with average annual rainfall amount, but surprisingly it correlated poorly with RWS rainfall variability. Similarly, Y% correlated negatively but less strongly (R 2 = 0·33) with RWS average annual rainfall, and correlated poorly with RWS rainfall variability, which raises questions about how Australian farmers manage climate risk. Interestingly a negative relationship was found between Yg and variability of Yw for the 22 RWS (R 2 = 0·66), and a positive relationship between Y% and Yw variability (R 2 = 0·23), which suggests that farmers in lower yielding, more variable sites are achieving yields closer to Yw. The Yg estimates appear to be quite robust in the context of estimates from other Australian studies, adding confidence to the validity of the GYGA protocol. Closing the national yield gap so that Ya is 0·80 of Yw, which is the level of Yg closure achieved consistently by the most progressive Australian farmers, would increase the average annual wheat production (20·9 million t in 1996/07 to 2010/11) by an estimated 15·3 million t, which is a 72% increase. This indicates substantial potential for Australia to increase wheat production on existing farmland areas using currently available crop varieties and farming practices and thus make a substantial contribution to achieving future global food security.

The effects of simulated additional rain (ear wetting, 25 mm) or of rain shelter imposed at different periods after anthesis on grain quality at maturity and the dynamics of grain filling and desiccation were investigated in UK field-grown crops of wheat (Triticum aestivum L., cvar Tybalt) in 2011 and in 2012 when June–August rainfall was 255·0 and 214·6 mm, respectively, and above the decadal mean (157·4 mm). Grain filling and desiccation were quantified well by broken-stick regressions and Gompertz curves, respectively. Rain shelter for 56 (2011) or 70 days (2012) after anthesis, and to a lesser extent during late maturation only, resulted in more rapid desiccation and hence progress to harvest maturity whereas ear wetting had negligible effects, even when applied four times. Grain-filling duration was also affected as above in 2011, but with no significant effect in 2012. In both years, there were strong positive associations between final grain dry weight and duration of filling. The treatments affected all grain quality traits in 2011: nitrogen (N) and sulphur (S) concentrations, N : S ratio, sodium dodecyl sulphate (SDS) sedimentation volume, Hagberg Falling Number (HFN), and the incidence of blackpoint. Only N concentration and blackpoint were affected significantly by treatments in 2012. Rain shelter throughout grain filling reduced N concentration, whereas rain shelter reduced the incidence of blackpoint and ear wetting increased it. In 2011, rain shelter throughout reduced S concentration, increased N : S ratio and reduced SDS. Treatment effects on HFN were not consistent within or between years. Nevertheless, a comparison between the extreme treatment means in 2012 indicated damage from late rain combined with ear wetting resulted in a reduction of c. 0·7 s in HFN/mm August rainfall, while that between samples taken immediately after ear wetting at harvest maturity or 7 days later suggested recovery from damage to HFN upon re-drying in planta. Hence, the incidence of blackpoint was the only grain quality trait affected consistently by the diverse treatments. The remaining aspects of grain quality were comparatively resilient to rain incident upon developing and maturing ears of cvar Tybalt. No consistent temporal patterns of sensitivity to shelter or ear wetting were detected for any aspect of grain quality.

The current study investigated use of a controlled misting environment to simulate field conditions that have been implicated in high levels of the malting barley defect, grain skinning. More than 200 spring barley varieties were assessed to identify those varieties that were particularly resistant or susceptible to the defect. Relationships between skinning severity and the traits ear length, floret number, grain number and grain weight were examined among the varieties. In a panel of seven varieties chosen as treatment controls, misting was found to significantly increase skinning severity. The misting treatment had no effect on measured ear traits of these varieties. Among the 200 varieties grown under the misting treatment, there was a continuous spectrum of skinning severities, which were not correlated with ear length, floret number, grain number or grain weight. Using the misting treatment, differences in susceptibility to grain skinning could be determined among varieties. As the misting treatment did not affect measured ear traits, and no correlation was found between ear traits and skinning severity among varieties, the effect of misting on skinning severity must be mediated through other physiological characteristics.

Twenty Small Tailed Han (STH) and 20 Ujumqin (UJU) ewes naturally infected with gastrointestinal nematodes were randomly assigned to one of four treatments arranged in a 2 × 2 factorial design, receiving anthelmintic treatment (AT) or non-anthelmintic treatment (NonAT) prior to lambing. After lambing, the effects of AT on feed intake, digestion and milk yield in ewes, and the growth rates of lambs fed their mother's milk were assessed for 28 days. Faecal samples were collected to determine faecal egg counts (FECs), milk was collected to measure milk yield and ewes and lambs were weighed to quantify daily body weight change. The results showed that AT significantly increased ewe dry matter intake (2411 g/d for AT and 2209 g/d for NonAT) and decreased FECs (50 eggs/g for AT and 2655 eggs/g for NonAT). All ewes lost weight after lambing, but body weight loss in the AT (43 g/d) was significantly less than in NonAT (84 g/d), and STH ewes (70 g/d) lost more weight than UJU ewes (58 g/d). Anthelmintic-treated ewes produced more milk for their lambs to consume. However, the extent of these positive effects of AT differed between STH and UJU ewes. The average daily body weight gain of lambs in AT was higher than those in NonAT. In conclusion, effective AT in ewes before lambing benefits subsequent lactation in ewes and growth rate in lambs.

A range of options was explored to test the hypothesis that diets for dairy cows could be formulated to reduce the carbon footprint (CFP) of feed, increase efficiency of conversion of potentially human-edible feed into milk, increase nitrogen use efficiency (NUE) and reduce methane (CH4) emissions per kg milk. Diets based on grazed grass, grass silage, maize silage or straw, supplemented with raw material feeds, were formulated to meet requirements for metabolizable energy and metabolizable protein for a range of daily milk yields. At similar levels of milk yield, NUE, predicted CH4 emissions and diet CFP were generally higher for diets based on maize silage than for those based on grazed grass, grass silage or straw. Predicted CH4 emissions and human-edible proportion decreased, while NUE increased with the increasing level of milk yield. It is concluded that there is potential to reduce the environmental impact of milk production by altering diet formulation, but the extent to which this might occur is likely to depend on availability of raw material feeds with low CFPs.

On steep slopes, grazing is associated with elevated physical activity. This is assumed to influence muscle metabolism, carcass and meat quality in beef cattle. However, there is a lack of experiments which allow distinguishing between physical activity and other factors of influence. In the present experiment, a setup was applied which excluded other factors as best as possible. Two groups of 12 Angus-sired suckling calves were each kept on high altitude pastures with either steep (whole area with about 40% inclination; S-calves) or with flat areas (0% inclination; F-calves). The two areas offered forage of similar nutritional quality. The calves, initially 18 ± 2·5 weeks old, were kept with their dams on the pastures for 11 weeks in a rotational grazing system. The calves were equipped with pedometers and rumination sensors to record physical activity and feeding behaviour, respectively. Slaughter took place on two dates immediately after the grazing period and carcass quality was assessed. Muscle fibre types were classified according to their contractile metabolism and post mortem (p.m.) protein degradation was quantified. The meat, aged for 21 days, was subjected to various physicochemical analyses and sensory evaluation. S-calves walked more steps and spent more time lying down than F-calves, whereas feeding behaviour was not affected by pasture inclination. The daily gains of S-calves were 10% lower compared with those of F-calves. Carcass characteristics were not influenced by pasture inclination. S-calves had a larger proportion of fast-twitch type IIX/B muscle fibres than F-calves. The opposite was observed for intermediate type IIA muscle fibres, whereas the proportion of slow-twitch type I muscle fibres was unaffected. Occasional differences were observed between S- and F-calves regarding indicators of p.m. proteolysis. In S-calves, compared with F-calves, meat from the longissimus thoracis muscle was juicier and showed a tendency to be of lighter colour, whereas meat from the biceps femoris muscle had a smaller shear force (24·5 v. 27·5 N in F-calves). In conclusion, 11 weeks’ exposure to environments forcing calves to exhibit different physical activities in a hypoxic environment was sufficient to cause adaptations in muscle metabolism and several, though small, differences in meat quality.