Wheat (Triticum aestivum L.) quality is a major focus of wheat breeding, which is influenced by multiple factors. The Huang-Huai wheat region, one of the main wheat-producing areas in China, provides favourable conditions for cultivating wheat cultivars with strong-gluten and medium-strong-gluten. In this study, a systematic assessment of seven crucial quality traits and important genetic loci (Glu-1 and Sec-1) in 436 wheat cultivars in the Huang-Huai wheat region of China by principal component analysis (PCA) and fuzzy comprehensive evaluation (FCE) methods showed that the stability time (ST), stretch area (SA), and maximum resistance (MAXR) were identified as three key factors, which significantly influenced wheat quality. Glu-1 and Sec-1 primarily impacted these three traits and subsequently influenced wheat quality. Compared to Glu-A1 and Glu-B1, Glu-D1 has a more significant impact on the comprehensive evaluation value D, principal components PC1-PC3, and the main traits ST, SA and MAXR of PC1. Wheat cultivars carrying the high-molecular-weight glutenin subunit (HMW-GS) Dx5+Dy10 exhibited a notable improvement in ST, SA, and MAXR traits compared with those carrying HMW-GS Dx2+Dy12, suggesting that Dx5+Dy10 may enhance wheat quality by improving ST, SA, and MAXR. By combining the results of D value, GYT (genotype by yield×trait) index, and HMW-GS score, 20 high-quality and high yield wheat cultivars were identified, which can be used as elite parents for wheat quality breeding.

Seed germination, which initiates the plant life cycle, exhibits high sensitivity to salt stress, a significant environmental factor limiting rice production.  Brassinosteroid (BR), a growth-promoting phytohormone, mitigates various stresses including salt, drought, and extreme temperatures in rice.  However, the mechanisms by which BR alleviates salt stress during seed germination remain inadequately characterized.  This study demonstrates that seed-specific overexpression of OsDWF4, a rate-limiting gene in BR biosynthesis, enhances rice germination.  The DWF4-OX lines, which increase endogenous BR content in seeds, promote germination under salt stress, corroborating results obtained through exogenous BR application.  Antioxidant enzyme analyses demonstrate that BR enhances the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT).  Metabolomic analysis reveals that BR mitigates salt stress primarily through the biosynthesis of phenylpropanoids and secondary metabolites.  Transcriptomic analysis indicates that both endogenous and exogenous BR share five co-regulated target genes and utilize a common biosynthetic pathway for stilbenoids, diarylheptanoids, and gingerols.  These findings confirm BR's capacity to enhance seed germination under salt stress and identify several BR-mediated targets for developing salt-tolerant rice varieties suitable for direct seeding cultivation.

Caffeine (CAF), a primary flavor component in tea, is one of the main reasons for the popularity of tea beverages.  As an important secondary metabolite in tea plants, the CAF content varied greatly among different tea accessions.  However, the genetic mechanisms underlying the CAF biosynthesis were still unclear.  In this study, we performed a genome-wide association study (GWAS) on 359 tea accessions in the Guizhou Plateau to identify genetic variation associated with CAF content.  A total of 19 significant single nucleotide polymorphisms (SNPs) and key gene (CsAK) involved in CAF biosynthesis were identified.  Subcellular localization revealed that the CsAK-GFP fusion protein was located on the cell membrane.  Antisense oligodeoxynucleotide (AsODN) targeting the CsAK gene to the buds and leaves revealed that the expression levels of the CsAK gene were significantly reduced, and the corresponding CAF content was also decreased in AsODN-treated tea plants.  Overexpression of the CsAK gene in eukaryotic cells resulted in the accumulation of key intermediate product (L-methionine) during CAF biosynthesis process.  These findings offered a theoretical foundation for future tea breeding programs aimed at cultivating excellent germplasm with high or low levels of CAF.

Primordial germ cells (PGCs) are the stem-cell population of adult animal gametes, which develop into sperm or eggs.  It can be propagated in vitro and injected into the host chicken for genome editing to obtain germline chimeric chicken.  However, it has the limitation that the host embryo contains endogenous PGCs, which raises complications, resultantly donor PGCs fail to compete, and transmission efficiency reduced.  Therefore, to increase the transmission efficiency, we generated a novel sterile chicken with the inducible elimination of endogenous PGCs in the host.  This is the first study that applied the herpes simplex virus thymidine kinase (HSV-TK) cell ablation system in avian.  CRISPR/Cas9-mediated homology-directed repair was performed to localize the HSV-TK suicide gene to the last exon of the deleted in azoospermia-like (DAZL) gene, and ganciclovir (GCV) was added to induce the apoptosis in the germ cells of the host embryo.  The sterilized host embryo introduced genome-edited PGCs to produce chimeric chicken carrying exogenous germ cells only.  It was observed that the germline transmission efficiency was 100% achieved, and the obtained chicks were purely from donor breeds.  The technologies established in the current study have important applications in germplasm conservation and gene editing in chicken.

The female inflorescence, or ear, of maize develops no branch meristem (BM), which differs from the male inflorescence, or tassel.  While the mutations of some well documented genes, such as fea2/3/4 and ramosa1/2/3, can cause the branched architecture of ears in maize, such mutations also change the normal phenotypic performance of the tassels.  In the present study, a natural maize mutant with branched ears, named branched ear1 (be1), was characterized.  be1 shows several branched ears at the base of the central ear with unchanged architecture of the tassels.  Besides, both the branched and central ears of be1 possess regularly arranged kerels.  The phenotypic characteristics of be1 differ completely from those reported mutants of fasciated ears or RAMOSA-like ears in maize.  An SEM survey at the very early development stage showed that meristems with three protrusions, similar to the BM in tassels, were present during the development of the branched ears in be1.  Gene mapping and sequence alignment suggested that TEOSINTE BRANCHED1 (TB1) was the candidate gene of BE1.  Further verification showed that a be1-specific 31 bp deletion at the downstream of BE1 led to statistically reduced expression of this gene in the immature ear, which serves as the potential causal reason for the branched ears of be1.  CRISPR/Cas9-based gene editing downstream of TB1 complemented the phenotypic architecture of branched ears, suggesting that TB1 was the target of BE1, and it was named as ZmTB1^be1.  The results of the present study implied a novel function of TB1 in female inflorescence development, rather than shaping the plant architecture in maize.  Meanwhile, further functional dissection of ZmTB1^be1 might shed new light on TB1, the most famous domestication related gene in maize.

The response of plant functional diversity to external disturbances not only effectively predicts changes in the ecosystem but it also reflects how plant communities use external environmental resources.  However, research on how different herbivore assemblages affect plant functional diversity is limited.  Therefore, this study systematically explored the effects of three typical herbivore assemblages (yak grazing, Tibetan sheep grazing, and mixed grazing by yaks and Tibetan sheep) on species richness, plant functional diversity, and soil physicochemical properties in alpine grasslands on the Qinghai-Tibet Plateau, China.  This study further investigated the primary mechanisms driving the changes in plant functional diversity.  The results indicate four key aspects of this system: (1) Grazing significantly enhanced plant functional diversity, particularly when the mixed grazing by yaks and Tibetan sheep was applied at a ratio of 1:2.  This ratio showed the most substantial improvement in the functional dispersion index and Rao’s quadratic entropy index.  (2) Compared to enclosed treatments, grazing increased species richness and β-diversity, contributing to higher plant functional diversity.  (3) Grazing treatments affected various plant traits, such as reducing plant community height and leaf thickness while increasing specific leaf area.  However, the impact on plant functional diversity was most pronounced under the mixed grazing by yaks and Tibetan sheep at a ratio of 1:2.  (4) Species α-diversity was positively correlated with plant functional diversity.  Changes in plant functional diversity were primarily regulated by variations in soil physicochemical properties.  Specifically, increases in soil available nitrogen significantly promoted changes in plant functional diversity, while increases in soil available potassium and bulk density had a significant inhibitory effect on these changes.  Long-term grazing significantly reduced the height of plant communities in alpine meadows, while a balanced mixture of yak and Tibetan sheep grazing, especially at a ratio of 1:2, enhanced plant functional diversity the most.  This suggests that, under these conditions, the use of external environmental resources by the plant community is optimized.

The agro-pastoral ecotone epitomizes the ecologically fragile semi-arid zone, where the soil microbiomes play a pivotal role in regulating its multifunctionality.  However, whether and how changes in soil structure and organic matter composition under different land uses affect microbial community structure remain unclear.  Here, land-use types in the agro-pastoral ecotone, including shrubland (BF), artificial grassland (ArG), abandoned grassland (AbG), and maize farmland (MA), were chosen to explore the response relationships between soil microbial communities and the aggregates and dissolved organic matter (DOM) composition.  The results showed that compared to MA, the macroaggregates in BF, AbG, and ArG were increased by 123.0, 92.79, and 63.71%, respectively, while MA soil had the greatest abundance of <100 μm particles.  The higher aromatic carbon with high aromaticity and molecular weight in BF soil DOM contributed to its highest mineral-associated organic carbon level (12.61 g kg^–1), while MA soil organic carbon had highly efficient decomposition due to its high content of aliphatic and carboxy carbon, so it is prone to loss from the active carbon pools.  The transition in land use from shrubland to grassland and farmland has facilitated the conversion of stable aromatic carbon to unstable carboxy carbon.  The taxonomic analysis revealed that soil bacterial and fungal communities in the four land uses were dominated by Proteobacteria, Actinobacteriota, Chloroflexi, and Ascomycota.  More taxonomic groups from phylum to family were enriched in BF soil.  The DOM components and organic carbon are crucial variables shaping the composition of soil bacterial communities, jointly explaining 61.66% of the variance, while aggregates are important variables driving the composition of fungal communities, with an explanation rate of 20.49%.  Our results suggest that DOM components and aggregates impact the soil microbial structure; and the transition in land use from agricultural land to grassland and shrubland in the agro-pastoral ecotone enhances aggregate stability, carbon sequestration potential, and microbial diversity.

Bacillus thuringiensis (Bt) cotton production is challenged by two main problems, i.e., the low concentration of Bt protein at the boll setting stage and the lowest insect resistance in bolls among all the cotton plant’s organs.  Therefore, increasing the Bt protein concentration at the boll stage, especially in bolls, has become the main goal for increasing insect resistance in cotton.  In this study, two protein degradation inhibitors (ethylene diamine tetra acetic acid (EDTA) and leupeptin) were sprayed on the bolls, subtending leaves, and whole cotton plants at the peak flowering stage of two Bt cultivars (medium maturation Sikang 1 (SK1) and early maturation Zhongmian 425 (ZM425) in 2019 and 2020.  The Bt protein content and protein degradation metabolism were assessed.  The results showed that the Bt protein concentrations were enhanced by 21.3 to 38.8% and 25.0 to 38.6% in the treated bolls of SK1 and ZM425 respectively, while they were decreased in the subtending leaves of these treated bolls.  In the treated leaves, the Bt protein concentrations increased by 7.6 to 23.5% and 11.2 to 14.9% in SK1 and ZM425, respectively.  The combined application of EDTA and leupeptin to the whole cotton plant increased the Bt protein concentrations in both bolls and subtending leaves.  The Bt protein concentrations in bolls were higher, increasing by 22.5 to 31.0% and 19.6 to 32.5% for SK1 and ZM425, respectively.  The organs treated with EDTA or/and leupeptin showed reduced free amino acid contents, protease and peptidase activities and significant enhancements in soluble protein contents.  These results indicated that inhibiting protein degradation could improve the protein content, thus increasing the Bt protein concentrations in the bolls or/and leaves of cotton plants.  Therefore, the increase in the Bt protein concentration without yield reduction suggested that these two protein degradation inhibitors may be applicable for improving insect resistance in cotton production.

The effects of mepiquat chloride (DPC) on the Cry1Ac protein content in Bacillus thuringiensis (Bt) cotton boll shells under high temperature and drought stress were investigated to provide a theoretical reference for Bt cotton breeding and high-yield and -efficiency cotton cultivation.  This study was conducted using Bt cotton cultivar ‘Sikang 3’ during the 2020 and 2021 growing seasons at Yangzhou University Farm, Yangzhou, Jiangsu Province, China.  Potted cotton plants were exposed to high temperature and drought stress, and sprayed with either 20 mg L⁻¹ DPC or water (CK).  Seven days after treatment, the Cry1Ac protein content, α-ketoglutarate content, pyruvic acid content, glutamate synthase activity, glutamic oxaloacetic transaminase activity, soluble protein content, and amino acid content were measured, and transcriptome sequencing was performed.  DESeq was used for differential gene analysis.  Under the DPC treatment, the Cry1Ac protein content increased by 4.7–11.9% compared to CK.  The α-ketoglutarate content, pyruvic acid content, glutamate synthase activity, glutamic oxaloacetic transaminase activity, soluble protein content, and amino acid content all increased.  Transcriptome analysis revealed 7,542 upregulated genes and 10,449 downregulated genes for DPC vs. CK.  Gene ontology (GO) and Kyoto Encyclopedia of Gene and Genomes (KEGG) analyses showed that the differentially expressed genes were mainly involved in biological processes, such as carbon and amino acid metabolism.  For example, genes encoding 6-phosphofructokinase, pyruvate kinase, glutamic pyruvate transaminase, pyruvate dehydrogenase, citrate synthase, isocitrate dehydrogenase, 2-oxoglutarate dehydrogenase, glutamate synthase, 1-pyrroline-5-carboxylate dehydrogenase, glutamic oxaloacetic transaminase, amino-acid N-acetyltransferase, and acetylornithine deacetylase were all significantly upregulated.  The DPC treatment increased pyruvate, α-ketoglutarate, and oxaloacetate by increasing the operational rate of the glycolytic pathway of the citric acid cycle.  It also significantly upregulated the genes encoding glutamate synthase, pyrrolidine-5-carboxylic acid dehydrogenase, glutamate oxaloacetate transaminase, and N-acetylglutamate synthetase, while it downregulated the genes encoding glutamine synthetase.  Therefore, the synthesis of aspartic acid, glutamic acid, pyruvate, and arginine increased after treatment with DPC, and the Cry1Ac protein content was increased by regulating carbon and amino acid metabolism.

Filament-like plant proteins are intermediate filament proteins that play a major part in the development and growth of plants.  However, no systematic identification and characterization have been conducted on the FPP family in plants.  Fifty nine FPP candidates were found in this work by analyzing the genomes of two dicots and four monocots.  Phylogenetic analysis and multicollinearity mapping showed the relatively conserved evolution of FPP genes in monocots.  Herein, eight OsFPPs were characterized and found to be induced or repressed by abiotic stresses.  Additional genetic evidence shows that OsFPP7-overexpressing rice exhibited increased sensitivity to abscisic acid during the germination stage, disrupted Na⁺/K⁺ homeostasis, and disrupted the balance of reactive oxygen species during the seedling stage when exposed to salt stress.  Conversely, knockout of osfpp7 alleviated ABA sensitivity, safeguarded the antioxidant system and sodium ion transport system, and thus enhanced rice salt tolerance.  The cytoskeleton, FPPs’ function in controlling salt stress and plant stress tolerance mechanisms are all further elucidated by our findings.

Potassium (K) improves the grain yield and stress resistance of crops; however, its effect on rice under shading stress is unclear.  In this study, a two-factor split-plot experiment was conducted in Sichuan, China, to evaluate the influence of K management methods on the morphological and physiological characteristics of leaves and grain yield under shading stress.  The results showed that leaf morphological and physiological traits had a greater relationship with grain yield under shading stress than under full sunlight.  Compared to full sunlight control, shading stress significantly increased the leaf area index (LAI) by improving the green leaf number and leaf area of rice.  Shading stress also significantly increased the chlorophyll, K⁺, and Na⁺ contents, but decreased the specific leaf weight, ratios of grain-to-leaf area and chlorophyll a/b, net photosynthetic rate (P_n), and sucrose and starch contents.  This resulted in a 16.21–29.71% reduction in grain yield by reducing the seed setting rate and 1,000-grain weight.  Compared to the no potassium application control (K_0-0), the green leaf number and leaf area of rice were significantly increased by K fertilizer, resulting in 15.61–29.88% and 13.46–22.20% increases in the total LAI under full sunlight control and shading stress, respectively.  K fertilizer significantly improved the chlorophyll b, K⁺, and K⁺/Na⁺ contents, but decreased the chlorophyll a/b ratio under shading stress, thereby enhancing P_n and increasing the sucrose and starch contents of flag leaves.  Therefore, K fertilizer significantly increased the grain yield by 5.57–17.35% under shading stress.  Compared to 90 kg ha^-1 of K₂O single use as basal fertilizer (K_90-0), 90 kg ha^-1 of K₂O single use as panicle fertilizer at panicle initiation stage (K_0-90) significantly increased the P_n and starch content of flag leaves under shading stress.  Furthermore, there was no significant difference between the grain yields of K_0-90 and 180 kg ha^-1 of K₂O equal-spilt applicated as basal and panicle fertilizers (K_90-90) in 2021 (except under shading stress) and 2022.  Overall, K fertilizer, particularly panicle K, improved the LAI and photosynthetic performance of rice, resulting in an improved rice grain yield under shading stress.