Multi-environment trials were conducted to investigate the quality potential of synthetic-derived cultivars (SDCs) and non-synthetic-derived cultivars (NSCs) in south-western China. The environmental effect was greater than genotypic for most protein quantity and quality parameters. The genotype effect was greater for falling number and the parameters from the rapid visco analyser (RVA). In terms of group means, grain protein content, wet gluten content, falling number, and RVA parameters were all significantly lower in SDCs than NSCs. No differences in the parameters reflecting dough strength (Zeleny sedimentation volume and farinograph parameters) were found between the two groups. Significant differences existed within each group, and the degree of variation was especially great in SDCs, among which Chuanmai 104 performed well in various quality parameters. Germination index at physiological maturity varied greatly among cultivars, with the lowest being Chuanmai 104, and the SDCs significantly lower than the NSCs. Although delayed harvest resulted in a significant reduction in falling number, partial SDCs such as Chuanmai 104 and Chuanmai 42 expressed relatively small reductions. In summary, SDCs exhibit a higher degree of variation in quality parameters; these findings indicate their large potential for breeding high-quality cultivars in south-western China.

The colour of Asian yellow alkaline noodles is an important indicator of quality and influences consumer choice. Apigenin di-C-glycosides (ACGs) and lutein present in wheat flour have been reported to contribute to the yellow colour; however, their relative roles have not been quantified. This study was conducted to quantify the contribution of ACGs to the part of the yellow colour that develops in the presence of alkaline salts and to assess the potential for improving colour.

Whereas lutein is present in all grain tissues, ACGs are concentrated in the embryo. Significant genetic variation was apparent for ACG content, but there was no significant correlation between grain content and the amount recovered in milled flour. The yellow colour caused by the reaction of flour constituents with alkali was estimated to be ∼5–6 b* units or ∼22–27% of total yellow colour. However, only 1–2 units (5–10% of total yellow colour) could be attributed to ACGs, suggesting that a significant portion of the yellow colour of alkaline noodles is due to other unidentified factors or compounds.

Innovative approaches and new efficiencies in plant breeding are required to accelerate the progress of genetic improvement through selection. One such approach is the application of prognostic breeding, which is an integrated crop-improvement methodology that enables selection of plants for high crop yield potential by evaluating its two components: plant yield potential and stability of performance. Plant yield and stability are assessed concurrently in each generation by utilising the plant prognostic equation. The genetic material used for this study was 2350 F₂ plants (C0) of the commercial maize hybrid Costanza. The study presents the results of the application of prognostic breeding for 6 years in two contrasting environments (A and B), starting from C0 and ending in C5. It utilises ultra-high selection pressures (1.5% to 0.5%) to isolate superior lines with crop yield comparable to Costanza, and estimates the annual genetic gain accomplished through application of this selection strategy. Application of prognostic breeding led to the isolation of superior lines whose productivity was comparable to Costanza. The productivity gap between Costanza and the best selection was reduced from 87% (C0) to 0.5% (C5) in trial 1 (environment A), from 87% (C0) to 2% (C5) in trial 2 (environment B) and from 70% (C0) to 1% (C3) in trial 3 (environment B). Genetic gain was much higher (up to 50%) in the early cycles C0–C2 of prognostic breeding and smaller in cycles C3–C5. The best lines selected were evaluated in randomised complete block trials across both environments and 2 years. Across years, the top two lines in environments A and B averaged 87% and 91% of the Costanza yield, respectively, and they had higher prolificacy (greater number of ears per plant) than Costanza. Across all cycles, the average annual genetic gain ranged from 23% to 36% in the different trials, providing evidence that selection efficiency can be significantly maximised by using this breeding strategy.

Iron (Fe) deficiency is frequently encountered on calcareous soils and is usually overcome by application of Fe fertilisers. In the present study, maize plants (Zea mays L. cv. Merit) grown in calcareous soil were foliar-sprayed with or without 100 µg Fe g^–1 in the forms of Fe₃O₄ nanoparticles (NPs) and ethylene diamine-N,N-bis(2-hydroxyphenylacetic acid) Fe sodium complex (Fe-EDDHA), at different growth stages. Uptake and translocation of Fe within the plant were monitored by atomic absorption spectroscopy, vibrating sample magnetometer, dynamic light scattering and transmission electron microscopy, and physiological parameters were evaluated. Iron treatments improved maize photosynthesis and hydrogen peroxide and superoxide anion scavenging capacity and lowered the rate of membrane lipid peroxidation. Iron treatment also accelerated vegetative growth and caused earlier entrance to the generative phase. Differences between ameliorative effects of Fe-EDDHA and Fe₃O₄ NPs were particularly noticeable in the generative growth phase. Improvement of calcium, Fe² , total Fe, and ferritin contents were more pronounced in Fe₃O₄ NPs treatments (164%, 200%, 300%, and 200% of the control, respectively). Improved growth of maize treated with Fe₃O₄ NPs can be attributed, at least in part, to the increase in ferritin and its critical role in maintenance of Fe homeostasis and balance of the plant redox system.

Achieving a fast initial growth is crucial for legumes because grasses grow more rapidly and compete much better with forbs. In a pot experiment with a nutrient-deficient soil, we added nitrogen (N), phosphorus (P) and N   P to pure and mixed stands of Lotus tenuis and Festuca arundinacea and investigated the effects of on plant growth, nutrient uptake and symbiotic associations with arbuscular mycorrhizae and rhizobia. Plant yield, N and P acquisition, mycorrhizal colonisation, rhizobial nodulation and root length were measured and root diameter and root surface area were calculated after two harvests. Species responded differently to specific nutrients when grown pure or mixed. Comparing pure with mixed stands in soils fertilised with P and N   P, L. tenuis showed decreased shoot and particularly root biomass, whereas F. arundinacea showed increases in both biomasses. This suggests that the competitiveness of the grass with the legume increased upon P and N   P addition. In mixed stands, F. arundinacea produced 51–64% of the total shoot biomass and 69–74% of the total root biomass with P and N   P, respectively. Root length and root surface area were greater and the roots thinner in F. arundinacea than in L. tenuis. Addition of P and N   P increased rhizobial nodulation in legume roots but decreased mycorrhizal colonisation in both plants. Supply of N does not necessarily favour grasses, whereas P supply favours legumes. Optimisation of P nutrition might help to maximise N inputs into grasslands by symbiotic N-fixation and decrease inputs of inorganic N by fertilisation.

Nitrogen (N) fertiliser is almost universally used in high-yielding irrigated cotton, but it is not used efficiently in many instances. Predicting the economic optimal amount of N fertiliser is difficult and often little N fertiliser is required where situations have provided access to N through excessive N fertiliser being applied to previous cotton crops, conditions promoting significant N mineralisation, or if legume rotation crops were grown. The economic optimum N fertiliser rate (Nopt – where the marginal cost of N fertiliser (at $1.50 kg^–1 N) equalled the return on cotton lint (at $2.20 kg^–1) was determined in eight experiments conducted over 8 years; Nopt ranged from 0 to 248 kg N ha^–1, lint yields ranged from 1.3 to 3.4 t ha^–1, crop N uptake ranged from 96 to 321 kg N ha^–1 and apparent N fertiliser recovery (calculated by dividing the difference in crop N uptake between N-fertilised and unfertilised plots by the N fertiliser applied) ranged from 20% to 98% of N applied. A positive response to N fertiliser application in lint yield was evident in 7 of the 8 years. Both lint yield and crop N uptake were positively correlated with pre-sowing soil nitrate concentration. Cotton that yielded 1.4 t lint ha^–1 derived 78% of crop N from the soil, whereas at 3.4 t lint ha^–1, 69% of crop N was derived from soil; this indicated the importance of N supplied from the soil and the relatively lesser reliance on the N fertiliser applied, even for very high-yielding cotton. A multiple regression model, using the parameters of pre-sowing soil nitrate, crop N uptake and lint yield, more accurately represented the data generated in this study in estimating the economic optimum N fertiliser rate (r² = 0.80).

Faba bean (Vicia faba L.) is one of the oldest grain legumes and is grown in many countries for both human consumption and animal feed. Faba bean rust, caused by Uromyces viciae-fabae, is a serious disease of faba beans in the subtropical agricultural region of Australia. Experiments were conducted to assess the genetic variation for rust resistance in Australian faba bean germplasm and to determine the genetic basis of rust resistance in selected germplasm. Resistant lines were identified, subsequently crossed to agronomically suitable parents and the ensuing progeny were evaluated for resistance. Many derived lines showed a higher level of resistance than the current cultivars, although none were rated immune. This level of resistance was considered adequate for reliable crop production when combined with limited fungicide application. Genetic studies from the seedling test of F₂ and F₃ progenies derived from two crosses based on two different sources of resistance showed three distinct responses; highly resistant, moderately resistant and susceptible. However, no homozygous family with a moderate response was found in the F₃ progeny test, hence, this infection type could not be attributed to independent gene(s). The segregation ratio in both F₂ and F₃ in the population derived from Doza#12035, a selection from the commercial cultivar Doza, indicated a single dominant gene was responsible for conferring resistance. In the other population developed from the resistant parent Ac1655, it is likely that also a single dominant gene confers resistance even though the F₃ segregation ratio deviated significantly from a one gene hypothesis. An allelism test revealed that each of the resistant parents (Doza#12035 and Ac1655) carried a single and independent gene for resistance, thus providing at least two genes for breeders to choose or pyramid for improving the rust resistance in faba bean.

We conducted greenhouse experiments to compare 14 lucerne (alfalfa, Medicago sativa L.) germplasms for their survival following freezing. Some are collections adapted to the Grand River National Grasslands in South Dakota. We hypothesised that these collections might have developed a tolerance to survive the frigid growth conditions common there. Two of these collections, River side (RS) and Foster ranch (FR), showed greater freezing tolerance than the other germplasms tested, based on their consistent survival rates with or without cold acclimation. In multiple freezing studies, RS and FR had average survival rates of 74% and 79%, respectively, in contrast to the commercial cultivars Apica and CUF-101 (CUF) (64% and 24%, respectively). The average temperature at which 50% of ions in plant tissues leak out (LT₅₀) by freezing based on leaf electrolyte leakage was closely correlated with survival rates. Leaf LT₅₀ improved 2–3-fold after 3 days of cold acclimation, based on leaf electrolyte leakage analysis, reaching −18°C, –9.6°C, –8.5°C, and −5°C for RS, FR, Apica, and CUF, respectively. Comparison of total soluble sugars and relative water content in shoots before and after cold acclimation showed that they were not well correlated with freezing tolerance and could not explain the superior responses of RS and FR during cold acclimation. Transcript analysis of cold-responsive MsCBF1, MsCBF2 and CAS15B genes showed that RS, FR, Apica and CUF exhibited distinct patterns of cold induction. Although RS, FR and Apica showed a rapid or greater increase in expression level of one or two of these genes, CUF showed only a moderate induction in MsCBF2 and CAS15B transcripts, suggesting that expression of these genes may be a good molecular marker for freezing tolerance in lucerne. The findings provide evidence that freezing tolerance in lucerne is a complex trait and that a combination of different mechanisms may greatly improve freezing tolerance. RS and FR are potential resources in breeding for improving freezing tolerance in lucerne.

As a global forage legume, lucerne (alfalfa, Medicago sativa L.) is valuable for studying the evolutionary and ecological mechanisms of plant adaptation to freezing, owing to the characteristic of contrasting winter hardiness induced by autumn dormancy. Autumn-dormant lucerne plants often exhibit greater cold tolerance than non-dormant plants under natural field conditions. The study examined the autumn shoot growth of four diverse lucerne cultivars, and the influence of two sampling dates in late autumn, three sampling positions and four autumn-dormancy categories on cas18, vsp and corF gene transcripts during the first year of lucerne establishment. Results showed that in field-grown lucerne, non-dormant and highly non-dormant cultivars had greater shoot growth than a dormant cultivar in autumn. The level of transcripts of cas18 (which encodes a dehydrin-like protein) was highest in dormant cultivars and lowest in semi-dormant cultivars in both November and December; in particular, the cas18 transcripts in the crown remained highest in both November and December. The level of transcripts of vsp (which encodes vegetative storage protein) in all dormant cultivar tissues was highest in both November and December. In semi-dormant cultivars, the expression of vsp in the taproot increased compared with the lateral root and crown in November. The corF transcript in the dormant cultivar was markedly higher than in the semi-dormant cultivar and almost zero in the non-dormant and highly non-dormant cultivars. These results indicate that the significant impact of autumn dormancy and plant position on gene expression of cas18, vsp and corF occurring during autumn hardening, and continuing low temperatures, are likely to have significant consequences on lucerne productivity and its long-term persistence.

Temperate pastures that leak water below the root zone have been linked to an increase in dryland salinity in southern Australia through their conservative use of stored water. An experiment was conducted at Hamilton in south-western Victoria to test the hypothesis that deep-rooted, summer-active perennial pasture species can substantially reduce leakage. On topographic crests the experiment compared lucerne and chicory with a traditional perennial ryegrass variety with low summer activity, whereas on the poorly drained valleys the comparison was between tall fescue, kikuyu and a perennial ryegrass variety with high summer activity.

Lucerne developed a buffer of dry soil to a depth of at least 5 m. An empirical relationship with June–September rainfall indicated that with this dry buffer, leakage below the root zone would not occur even in the wettest of years. Chicory developed a dry buffer to the depth of measurement (3 m), but plant density gradually declined and leakage started to occur 5 years after sowing. The perennial ryegrass with low summer activity had leakage nearly every year. On the valleys kikuyu was initially the most effective at drying the soil in summer, but its density declined at the expense of annuals and 3 years after sowing it became wetter than the other treatments. None of the pasture options on the valley fully controlled leakage, but both the summer-active perennial ryegrass and tall fescue were persistent and there was little difference in their capacity to extract summer moisture.

This study showed that four characteristics were associated with a pasture that controlled leakage – summer activity, persistence, adequate density and deep rootedness. Of the species tested only lucerne satisfied all these criteria.