The coexistence of cereal cyst nematode (CCN) species Heterodera avenae and H. filipjevi, often involving multiple pathotypes, is a limiting factor for wheat production in China. Some of the known genes for resistance to CCN are not effective against both nematode species, hence complicating breeding efforts to develop CCN-resistant wheat cultivars. Here, we demonstrate that the CCN resistance in wheat cultivar Madsen to both Heterodera spp. is controlled by different genetic loci, both of which originated from Aegilops ventricosa. A new quantitative trait locus (QTL), QCre-ma7D, was identified and localized in a 3.77-Mb genomic region on chromosome arm 7DL, which confers resistance to H. filipjevi. QCre-ma2A on chromosome arm 2AS corresponds to CCN resistance gene Cre5 and confers resistance to H. avenae. This QTL is a new locus on chromosome arm 7DL and is designated Cre9. Three Kompetitive allele-specific PCR markers (BS00150072, BS00021745, and BS00154302) were developed for molecular marker-assisted selection of Cre9 and locally adapted wheat lines with resistance to both nematode species were developed. QCre-ma2A on chromosome arm 2AS corresponds to CCN resistance gene Cre5 and confers resistance to H. avenae. The identification of different loci underlying resistance to H. filipjevi and H. avenae and the development of adapted resistant entries will facilitate breeding of wheat cultivars that are resistant to these devastating nematodes in China.

The composition and form of selenium in the soil have significant effects on the selenium content of crops. In this study, we investigated the selenium absorption pathway in plants by studying the interaction between nitrogen fertilizer and soil selenium. Our results showed that the selenium concentration enrichment factors (CEF) varied within the same region due to nitrogen fertilizer application, where they ranged from 1.33 to 5.02. The soil selenium flow coefficient (mobility factor, MF) increased with higher nitrogen application rates. The sum of the MF values for each soil layer treated with nitrogen application rates of 192 kg hm⁻² and 240 kg hm⁻² was 0.70, which was 64% higher than that for the control group with no nitrogen application. In the 0–20 cm soil layer, the highest summed water-soluble and exchangeable selenium and relative percentage of total selenium (12.45%) was observed at a nitrogen application rate of 240 kg hm⁻². In the 20–40 cm soil layer, the highest relative percentage content of water-soluble and exchangeable selenium and total selenium (12.66%) was observed at a nitrogen application rate of 192 kg hm⁻². Experimental treatment of black wheat with various concentrations of sodium selenite showed that selenium treatment at 50 μmol L⁻¹ significantly increased the reduced glutathione (GSH) levels in the leaves and roots of seedlings, where the GSH contents increased by 155.4% in the leaves and by 91.5% in the roots. Further analysis of the soil–black wheat system showed that nitrogen application in selenium-rich areas affected the soil selenium flow coefficient and morphological composition, thereby changing the enrichment coefficient for leaves (0.823), transport capacity from leaves to grains (–0.530), and enrichment coefficient for roots (0.38). These changes ultimately affected the selenium concentration in the grains of black wheat.

Wide hybridization between wheat and wild relatives such as Thinopyrum intermedium is important for broadening genetic diversity and improving disease resistance in wheat. We developed 30 wheat-Th. intermedium derivatives. Here, we report assessments of their resistance to different pathogens including cereal cyst nematode (CCN; Heterodera spp.), Puccinia striiformis f. tritici Erikss. causing stripe rust, and Blumeria graminis f. tritici (DC.) Speer inciting powdery mildew. Under natural field infection, all the wheat-Th. intermedium lines were resistant to at least one of the pathogens, and four lines were resistant to multiple pathogens. Twenty-nine of 30 tested lines exhibited resistance to H. avenae, a dominant CCN species in wheat fields. Twenty-four lines were resistant to H. filipjevi, an emerging threat to wheat production. Tests of phenotypic responses in the naturally infected field nurseries identified six stripe rust-resistant lines and 13 powdery mildew-resistant lines. Mitotic observation demonstrated that these newly developed wheat-Th. intermedium derivatives included not only octoploid but also chromosome addition, substitution, and translocation lines. Chromosome compositions of the four lines resistant to multiple pathogens were analyzed by genomic in situ hybridization and fluorescence in situ hybridization. The octoploid lines Zhong 10-68 and Zhong 10-117 carried both intact Th. intermedium chromosomes and translocated chromosomes. Line Zhong 10-149 had 42 wheat chromosomes and two wheat ditelosomes plus a pair of T3BS·J translocated chromosomes. Line Zhong 10-160 carried 41 wheat chromosomes plus one pair of the J genome chromosomes of Th. intermedium. The multiple disease-resistant wheat-Th. intermedium derivatives, especially lines with chromosome counts close to that of common wheat, provide valuable materials for wheat resistance breeding programs.

Selenium (Se) biofortified wheat could enhance human health by providing essential Selenium. Different nitrogen application rates (0, 60, 120, 180, 240 and 300 kg N ha^–1) on soil Se speciations and contents, the differences of Se accumulation and yield of triticales were investigated. The concerntration of total Se, water-soluble Se (SOL_Se), and exchangeable Se (EXC_Se) in 0–20 cm and 20–40 cm soil layers showed an increasing trend from anthesis to maturity, and decreasing tendency as nitrogen application increasing. TZ-8293 compared to TH-3 exhibited the highest grain Se content and accumulation at the maturity, measured 77.00 μg kg^–1 and 73.11%, respectively. Compared to the control, the concentration of flour Se in TH-3, and TZ-8293 under the 240 kg N ha^–1 treatment significantly increased by 90.97 and 91.67%, respectively, and the yield of TH-3 under 240 kg N ha^–1 treatment was significantly the highest, measuring 7889.84 kg ha^–1. Following anthesis, net photosynthetic rate (P_n) showed an significantly increasing tendency with the application of nitrogen increased, however, transpiration rate (T_r), intercellular CO₂ and stomatal conductance (C_i), and g_s in flag leaf decreased significantly with the increase of nitrogen application rate. The correlation analysis showed that there were (extremely) significant negative correlations among Se content, yield and yield components (–0.30 ≤ R² ≤ –0.89), excessive nitrogen application may hinder the formation of soil available Se, which can have a negative impact on the absorption of Se, finally impede the biofortification of Se in triticale. In conclusion for locally Se-enriched triticale cultivation, it was recommended to apply nitrogen fertilizer rate of 120–240 kg N ha^–1 on TH-3.

The aim of this study was to investigate the effects of different N application rates on the yield, N accumulation, and grain quality of triticale and provide a theoretical basis for selecting the best N application rate for sowing triticale in the loess parent material area. This experiment was conducted at the experimental station of Shanxi Agricultural University in Jinzhong City, Shanxi Province, China, from 2021 to 2023 to study the effects and differences of different N application rates (N application rates 180, 210, 240, 270, and 300 kg ha⁻¹) on the yield formation, N utilization, and quality of the two triticale varieties Donghei10 (DH10) and Taizi6336 (TZ6336). The results showed that, compared with other N application rates, N240 increased the number of spikes and grains per spike of triticale and increased the yield by 6–19%. The yield increased most significantly when the N application range was 210–240 kg ha⁻¹; the yield change rate per 2 kg of N increase was the largest within this range, and the continued increase in yield with increasing N application was slow. N240 also improved the NUE, NUPE, nutritional quality, and processing quality of triticale. The results of the pathway analysis showed that the N application rate affected the spike number, grain number per spike, and 1000-grain weight of triticale. N accumulation at the anthesis and maturity stages affected GS and GOGAT activities in the flag leaf and grain, thus affecting the N efficiency, yield, and protein content. Overall, a N application at 240 kg ha⁻¹ increased the yield, nitrogen efficiency, and quality of triticale, and there was no significant difference in yield between DH10 and TZ6336.

Low-temperature stress significantly limits wheat growth and productivity. Poly-γ-glutamic acid (γ-PGA) is an environmentally friendly green molecular material that plays an important role in plant growth and regulation; however, its protective mechanisms against cold stress in wheat remain poorly understood. In this study, the effect of γ-PGA on both chilling (4 °C) and freezing (−18 °C) resistance in wheat seedlings and its underlying mechanisms were comparatively studied. The results showed that the γ-PGA-treated seedlings exhibited a 128.81% higher survival rate after freezing stress and maintained significantly greater biomass accumulation under both stress conditions (62.44% and 26.56% higher dry weight under chilling and freezing stress, respectively). A physiological analysis revealed that γ-PGA enhanced osmoprotectant (proline and soluble sugars) accumulation and activated key antioxidant enzymes (SOD, POD, and APX). Then, an RNA-seq analysis identified 11,401 and 7721 differentially expressed genes under chilling and freezing stress, respectively, with 3598 common genes constituting a core cold-response network. KEGG and GO analyses demonstrated significant enrichment in pathways related to carbon metabolism, glutathione metabolism, phenylpropanoid–flavonoid biosynthesis, fatty acid metabolism, and cell wall organization. Notably, γ-PGA strongly upregulated key genes in phenylpropanoid–flavonoid metabolism (TraesCS2B02G615000 and TraesCS2B02G624400), glutathione metabolism (TraesCS1B02G127900), and lipid metabolism (TraesCS1B02G018700). These results provide comprehensive molecular insights into γ-PGA-mediated cold tolerance and support its potential application in sustainable wheat production under low-temperature stress conditions.