Future progress on the creation of wheat cultivars with high grain zinc (Zn) and iron (Fe) mineral density will depend on both the availability of suitable donor germplasm and the identification of genes or quantitative trait loci contributing to increase the accumulation of mineral elements in the wheat kernels. Multi-environment field trials were conducted to evaluate the grain Zn, Fe and protein concentration of 32 bread wheat (Triticum aestivum L.) and 20 durum wheat (T. turgidum L. var. durum) landraces locally adapted to soils covering a wide range of pH values and mineral composition. These landraces were selected after a preliminary, small-scale field trial that had analysed 425 Spanish local varieties. Analyses of variance demonstrated a significant effect of genotype on grain composition, and 16 wheat landraces with elevated grain Zn and/or Fe density across the environments were identified. These landraces rich in grain minerals represent valuable primary gene-pool parents for wheat biofortification. No pattern of native soil geochemical characteristics that could help to predict the success in collecting mineral-dense genotypes in a given area was found. Mapping populations derived from some pairs of grain-mineral-rich and -poor genotypes characterised in the study may facilitate the development of molecular markers to assist the selection of superior wheat genotypes.

In this paper, we detected quantitative trait loci (QTLs) for two of the most important quality factors of Chinese white noodles (CWN), sensory quality and textural properties, using a recombinant inbred line (RIL) population containing 184 lines derived from the cross between two Chinese winter wheat (Triticum aestivum L.) varieties, Linmai6 and Tainong18. Twenty-six QTLs for eight sensory quality traits were identified on chromosomes 1A, 2A, 3A, 4A, 5A, 6A, 2B, 3B 4B, 5B, 6B 7B, 2D, 4D, 5D and 6D that explained 7.0–16.84% of the phenotypic variance. Fourteen QTLs associated with textural quality traits were identified on chromosomes 1B, 2D, 3A, 3B, 4A, 5B, 5D and 7D that explained 5.94–13.15% of the phenotypic variance. Six QTLs associated with hardness, adhesiveness, cohesiveness, gumminess, resilience and appearance were mapped to chromosome 4A, indicating that this chromosome was important for textural and sensory properties of CWN. This study furthers understanding of the genetic basis for sensory quality and textural properties of CWN and provides the basis for gene mapping of these traits.

Variety DUOII is a multi-ovary line of common wheat (Triticum aestivum L.) that has two or three pistils and three stamens. The multi-ovary trait is controlled by a dominant gene, the expression of which can be suppressed by the special heterogeneous cytoplasm of line TeZhiI (TZI). TZI has the nucleus of common wheat and the cytoplasm of Aegilops. DUOII (♀) × TZI (♂) shows the multi-ovary trait, whereas TZI (♀) × DUOII (♂) shows the mono-ovary trait. DNA methylation affects gene expression and plays a crucial role in organ and tissue differentiation. In order to study the relationship between DNA methylation and the suppression of the multi-ovary gene, we used methylation-sensitive amplification polymorphisms (MSAP) to assess the DNA methylation status of the reciprocal crosses. Genome-wide, 14 584 CCGG sites were detected and the overall methylation levels were 31.10% and 30.76% in the respective crosses DUOII × TZI and TZI × DUOII. Compared with DUOII × TZI, TZI × DUOII showed 672 sites (4.61%) in which methylation–demethylation processes occurred. The results showed that the special heterogeneous cytoplasm significantly changed DNA methylation, and this might have suppressed the multi-ovary gene. The results provide insight into the changing patterns of DNA methylation in the suppression of the multi-ovary gene, and provide essential background for further studies on the underlying mechanisms of heterogeneous cytoplasm suppression of the expression of the multi-ovary gene in wheat.

DNA methylation plays an important role in regulating plant development, including organ and tissue differentiation, which may determine variations in agronomic traits. However, no reports exist for the regulation of leaf colour in wheat. The present study investigated the chloroplast structure and epigenetic mechanisms regulating leaf colour in an albino mutant of wheat (Triticum aestivum L.) cv. Xinong 1376. Structural analysis was performed by scanning and transmission electron microscopy, and epigenetic modifications were detected by methylation-sensitive amplification polymorphism (MSAP) analysis. Mesophyll cells of green leaves showed a well-ordered arrangement and they were filled with chloroplasts with intact lamellar structures and thylakoid membranes. By contrast, mesophyll cells of red and white leaves were disorganised and contained only a few plastids or chloroplasts with no lamellar structures or thylakoid membranes. Comparison of MSAP profiles revealed that white or red leaves had higher levels of cytosine methylation and showed changes in polymorphic loci compared with green leaves (4.35% and 4.10%, respectively). We sequenced 150 DNA fragments that were differentially displayed in MSAP patterns of white or red and green leaves of the Xinong 1376 albino mutant. A further BLAST search of 77 cloned sequences located them in coding regions. Most of these sequences were found to be involved in processes such as signal transduction, transcription regulation, post-transcriptional processing, DNA modification and repair, transport, biosynthesis of cellulose, photosynthesis, protein ubiquitination, stress responses, and retroposition. Expression analysis demonstrated a decrease in the transcription of two methylated genes, psaA and psbD, which are involved in the photosystem. Although the DNA methylation changes and leaf colour changes were not directly associated, these results may indicate that methylation of specific genes is an active and rapid epigenetic response to variation of leaf colour in the Xinong 1376 albino mutant, further elucidating the mechanism of variation in leaf colour.

Most studies on the effects of climate change have been conducted on grain yield and composition; few have focused on seed germination and storage ability, especially in temperate crops. However, projected higher temperatures at the end of crop cycle are expected to affect not only seed nutritional quality but also seed germination and storage ability. In this study, experiments were conducted on wheat (Triticum aestivum L.) and pea (Pisum sativum L.) in controlled conditions to assess the effects of high maximum daytime temperatures, between 25°C and 35°C, on mother plants during grain filling or only during grain desiccation. Grain composition and seed characteristics related to germination and seed storage were investigated. When the stress occurred during grain filling, seed dry weight decreased, and protein and total fatty acid concentrations increased. Higher contents of vicilins in pea and polyunsaturated fatty acids in both crops were observed. Total starch content decreased in wheat. Sucrose : oligosaccharides ratio decreased, seed conductivity increased and germination was altered in both crops whenever the stress occurred. All of these modifications were mainly detrimental to the seed nutritional and end-use values. Further investigations should be carried out to assess genetic diversity, to characterise other species, and to introduce the impact of high temperatures on these seed characteristics into crop models.

A major constraint of lentil (Lens culinaris Medik.) cultivation is yield reduction due to field infestation by the seed beetles Bruchus spp. (bruchids). The aim of the study was to assess seed loss (SL) and yield loss (YL) due to bruchid infestation under organic and conventional farming, and to investigate genotypic variability for seed yield of 20 lentil varieties in response to bruchid damage. Field experiments were established over three consecutive years in two areas of central and northern Greece. SL was determined as the percentage of damaged seeds, whereas the weight of the damaged seeds was estimated as YL. Farming system was the main source of variation for both SL and YL. Mean SL under organic farming was 15% and mean YL was 0.13 t ha^–1. SL and YL were 2.6- and 8.4-fold higher, respectively, under organic than conventional farming. Valuable genotypic variability was observed with respect to both SL and YL. Early flowering and small seed size were traits associated with low SL and YL. Among varieties, mean SL ranged from 8.5% to 29.2% and YL from 0.06 to 0.31 t ha^–1. Evaluation for high yield potential, indicating bruchid tolerance, revealed two types of promising varieties: varieties with high yield and low seed bruchid damage due to phenological escape, and varieties with high yielding potential despite the high SL and YL.

Soybean mosaic virus (SMV) causes significant yield losses and seed-quality deterioration in the soybean (Glycine max (L.) Merr.) growing areas of China, and breeding disease-resistant cultivars is the most common approach for controlling the spread of the disease and the destruction of soybean crop. In this study, 97 widely grown soybean cultivars representing nine decades (1923–2006) of breeding from the four main soybean-producing subregions in China (Northern Heilongjiang (NH), Mid-Southern Heilongjiang (MSH), Jilin-Liaoning (JL) and Yellow–Huai-Hai River Valleys (YHH)) were inoculated with six prevalent SMV strains: SC3, SC7, SC8, SC11, SC15 and SC18. The average disease index (ADI) of the six SMV strains ranged from 26.95 to 48.97, and the numbers of resistant and susceptible cultivars to the six SMV strains ranged from 27 (27.8%) to 64 (66.0%) and 33 (34.0%) to 70 (72.2%), respectively. The ADIs of cultivars from NH, MSH, JL and YHH were 50.82, 47.27, 43.10 and 33.05, respectively. Soybean cultivars released in the 1940s and 1960s had the highest and lowest ADI values, 53.95 and 32.03, respectively. From NH and JL, all individual strain disease index (DI) values exhibited decreasing trend over time, but no decreasing trend in DI values was observed from MSH. From YHH, DI values for SC3 and SC18 displayed apparent increasing trend over time, and DI values for SC15 showed an obvious decreasing trend. In all, 24 soybean cultivars were identified as having broad-spectrum resistance, with ADI values ranging from 0.80 to 35.52 for the six SMV strains, and 13 soybean cultivars were identified as highly resistant to at least one SMV strain. The findings of this study will contribute to monitoring the pattern of spatio-temporal variation in SMV resistance in different soybean-producing areas of China and facilitate conventional and molecular breeding programs for SMV resistance in soybean.

Sugarcane is a source of roughage in animal feeding. It presents high production per unit of cultivated area, relatively easy cultivation and low cost of production per hectare, and better quality and a high dry matter (DM) yield in periods when forage is scarce. This study aimed to evaluate the effect of increasing levels of calcium hydroxide (Ca(OH)₂) in sugarcane forage on chemical composition, in vitro digestibility values of DM, neutral detergentfibre (NDF) and acid detergent fibre (ADF), and kinetics of thermal decomposition processes of weight loss and heat flow. Sugarcane was collected close to the ground and 50-kg heaps of the fresh material were formed and mixed with four doses of Ca(OH)₂ (0, 8, 16 and 24 g kg^–1 sugarcane). Concentrations of NDF and ADF decreased linearly with increasing amount of Ca(OH)₂, whereas concentration of hemicellulose increased linearly. In vitro digestibilities of DM, NDF and ADF were enhanced in a quadratic manner with increasing amounts of Ca(OH)₂. The release of heat, measured by ΔH, increased linearly with increased Ca(OH)₂ levels, likely due to enhanced digestibility of the fibre components. Weight loss decreased linearly between 272.2°C and 397.7°C with increased amounts of Ca(OH)₂ added to sugarcane, likely due to changes in cellulose structure, which became denser and thermodynamically more stable than native cellulose following the alkaline treatment. Calcium hydroxide changed chemical composition and digestibility of the fibrous fraction of sugarcane, resulting in better nutritional value. The greatest release of heat and highest in vitro digestibility of fibre were observed when adding 15.2 g Ca(OH)₂ kg^–1 sugarcane; therefore, this dose is recommended to enhance the nutritive value of sugarcane as ruminant feed.

Foliar and fruit application of mineral particle films is considered to reduce damage from heat and water stress significantly in many horticultural crops. Sprays with new formulations consisting of suspensions of calcium carbonate can have beneficial effects on vegetable crops, including tomato. We assessed the effects of a calcium carbonate suspension on physiology, yield and some quality aspects of a tomato crop under three levels of deficit irrigation (I₅₀, moderate; I₂₅, moderate–severe; I₀, severe) in the semi-arid climate of eastern Sicily. Leaf transpiration was significantly reduced by 47% (late June) and 58% (early July) in plants treated with the suspension. Late in the growing season, sprayed leaves were ∼1°C cooler than unsprayed (control) leaves. Spray treatment resulted in a higher marketable yield (+12%) than the control under I₅₀, and fruit quality was significantly improved under I₀. Treated tomatoes exhibited better firmness (+24%), higher contents of vitamin C (+15%) and total phenols (+12%), and higher antioxidant activity (5–7%) than untreated tomatoes. Application of calcium carbonate minimised fruit losses under I₅₀ while ensuring great water saving and improving the nutraceutical properties of fruits. These aspects make the technology an environmentally friendly tool to improve crop sustainability and nutritional quality in tomato.

Silvopastoral systems with the tree legume leucaena (Leucaena leucocephala (Lam.) de Wit) and grass pastures are widely used for ruminant feeding in subtropical and tropical regions. Different densities and planting configurations of leucaena will influence relative yields of both species because of intra- and interspecific competition. With the aim to describe the effects of competition between leucaena and Rhodes grass (Chloris gayana Kunth), a Nelder Wheel trial with 10 different leucaena tree densities (100–80 000 trees ha^–1) growing with and without Rhodes grass was established in a subtropical environment at Gatton, south-east Queensland, in November 2013. From 2014 to 2016, the biomass of leucaena (six harvests) and Rhodes grass (seven harvests) was measured by using allometric equations and the BOTANAL sampling procedure over 742 and 721 days, respectively. No complementary or facilitative aboveground interactions were observed between the leucaena and Rhodes grass components of the pasture system. Increasing leucaena tree density resulted in greater aboveground intra- and interspecific competition.

Average maximum individual tree yield (38.9 kg DM tree^–1 year^–1) was reached at 100 trees ha^–1 without grass competition and was reduced by 60% with grass competition. Rhodes grass biomass yield was negatively affected by shading from the leucaena canopy, with negligible grass yield at tree densities ≥8618 trees ha^–1. Therefore, there was effectively no grass competition on individual tree yield at higher leucaena densities. Accordingly, edible leucaena biomass per unit area was positively related to log₁₀ leucaena density (R² = 0.99) regardless of grass competition, reaching 21.7 t DM ha^–1 year^–1 (2014–15) and 27 t DM ha^–1 year^–1 (2015–16) at the highest leucaena density of 80 000 trees ha^–1. By contrast, the yield of Rhodes grass was linearly and inversely correlated with log₁₀ tree density (R² = 0.99). Practical implications for the design and management of commercial leucaena–grass pastures are discussed.

The Chinese native cool-season perennial grass species Festuca sinensis Keng ex E.B.Alexeev exhibits frequent asymptomatic infections with an asexual Epichloë fungal endophyte. Six Festuca sinensis ecotypes were collected in different geographical locations. Endophyte-positive (E+) plants and corresponding endophyte-free (E–) plants of these six ecotypes were identified and then measured for shoot morphological characteristics including plant height, tiller number and biomass. Significant difference due to different host ecotype was observed in both E+ and E– plants. However, significant difference due to endophyte was observed in only one or two ecotypes. Concentration of endophyte-derived alkaloids and semi-quantitative endophyte colonisation in E+ plants were also evaluated. All E+ plants produced both lolitrem B and peramine alkaloids, and significant variation in alkaloid concentration due to host ecotype or endophyte genotype was observed. Analysis of semi-quantitative endophyte colonisation by using qPCR revealed significant differences between ecotypes. This suggested that host ecotype had large impacts whereas the endophyte had only a minor effect. The results showed that endophyte, host ecotype and their complex interaction affected performance of Festuca sinensis ecotypes.