The foundation parents play key roles in the genetic improvement of both yield potential and end-use quality in wheat.  Characterizing the genetic basis that underlies certain beneficial traits in the foundation parents will provide theoretical reference for molecular breeding by a design approach.  ‘Kenong 9204’ (KN9204) is a candidate foundation parent characterized by ideotype, high yield potential, and particularly high nitrogen fertilizer utilization.  To better understand the genetic basis of its high yield potential, high throughput whole-genome re-sequencing (10×) was performed on KN9204, its parental lines and its derivatives.  A high-resolution genetic composition map of KN9204 was constructed, which showed the parental origin of the favorable genomic segments based on the identification of excellent yield-related quantitative trait loci (QTL) from a bi-parental mapping population.  Xiaoyan 693 (XY693), a wheat–Thinopyrum ponticum partial amphidiploid, contributed a great deal to the high yield potential of KN9204, and three major stable QTLs from XY693 were fine mapped.  The transmissibility of key genomic segments from KN9204 to its derivatives were delineated, indicating that haplotype blocks containing beneficial gene combinations were conserved along with directional selection by breeders.  Evidence for selection sweeps in the breeding programs was identified.  This study provides a theoretical reference for the breeding of high-yield wheat varieties by a molecular design approach.

Pre-harvest sprouting (PHS) adversely affects wheat quality and yield, and grain color (GC) is associated with PHS resistance.  However, the genetic relationship between GC and PHS resistance remains unclear.  In this study, 168 wheat varieties (lines) with significant differences in GC and PHS resistance were genotyped using an Illumina 90K iSelect SNP array.  Genome-wide association study (GWAS) based on a mixed linear model showed that 67 marker-trait associations (MTAs) assigned to 29 loci, including 17 potentially novel loci, were significantly associated with GC, which explained 1.1–17.0% of the phenotypic variation.  In addition, 100 MTAs belonging to 54 loci, including 31 novel loci, were significantly associated with PHS resistance, which accounted for 1.1–14.7% of the phenotypic variation.  Subsequently, two cleaved amplified polymorphic sequences (CAPS) markers, 2B-448 on chromosome 2B and 5B-301 on chromosome 5B, were developed from the representative SNPs of the major common loci Qgc.ahau-2B.3/Qphs.ahau-2B.4 controlling GC/PHS resistance and PHS resistance locus Qphs.ahau-5B.4, respectively.  Further validation in 171 Chinese mini-core collections confirmed significant correlations of the two CAPS markers with GC and PHS resistance phenotypes under different environments (P<0.05).  Furthermore, the wheat public expression database, transcriptomic sequencing, and gene allelic variation analysis identified TraesCS5B02G545100, which encodes glutaredoxin, as a potential candidate gene linked to Qphs.ahau-5B.4.  The new CAPS marker CAPS-356 was then developed based on the SNP (T/C) in the coding sequences (CDS) region of TraesCS5B02G545100.  The high-density linkage map of the Jing 411/Hongmangchun 21 recombinant inbred lines (RILs) constructed based on specific locus amplified fragment sequencing markers showed that CAPS-356 collocated with a novel QTL for PHS resistance, supporting the role of TraesCS5B02G545100 as the potential candidate gene linked to Qphs.ahau-5B.4.  These results provide valuable information for the map-based cloning of Qphs.ahau-5B.4 and breeding of PHS resistant white-grained varieties.

The tea plant [Camellia sinensis (L.) O. Kuntze] is an industrial crop in China.  The Anhui Province has a long history of tea cultivation and has a large resource of tea germplasm with abundant genetic diversity.  To reduce the cost of conservation and utilization of germplasm resources, a core collection needs to be constructed.  To this end, 573 representative tea accessions were collected from six major tea-producing areas in Anhui Province.  Based on 60 pairs of simple sequence repeat (SSR) markers, phylogenetic relationships, population structure and principal coordinate analysis (PCoA) were conducted.  Phylogenetic analysis indicated that the 573 tea individuals clustered into five groups were related to geographical location and were consistent with the results of the PCoA.  Finally, we constructed a core collection consisting of 115 tea individuals, accounting for 20% of the whole collection.  The 115 core collections were considered to have a 90.9% retention rate for the observed number of alleles (Na), and Shannon’s information index (I) of the core and whole collections were highly consistent.  Of these, 39 individuals were preserved in the Huangshan area, accounting for 33.9% of the core collection, while only 10 individuals were reserved in the Jinzhai County, accounting for 8.9% of the core set.  PCoA of the accessions in the tea plant core collection exhibited a pattern nearly identical to that of the accessions in the entire collection, further supporting the broad representation of the core germplasm in Anhui Province.  The results demonstrated that the core collection could represent the genetic diversity of the original collection.  Our present work is valuable for the high-efficiency conservation and utilization of tea plant germplasms in Anhui Province

The addition of silicon (Si) and organic fertilizers to soil conditioners can inhibit the transfer of heavy metal ions from soil to crops. However, it is not clear how Si and organic fertilizers affect soil properties and the micro-ecological environment and thereby reduce cadmium (Cd) accumulation in rice. In this study, the effects of L-type soil conditioners containing Si and organic fertilizers on bacterial and fungal community diversity, soil pH, organic matter, and available Si were analyzed with field experiments at two sites. With the increase of Si and organic fertilizer content in soil conditioner, rice yield respectively increased by 16.8-25.8% and 6.8-13.1%, and rice Cd content decreased significantly by 8.2-21.1% and 10.8-40.6%, respectively, at the two experimental sites. Soil microbiome analysis showed that the increase in abundance of Firmicutes and Actinobacteriota bacteria associated with Cd adsorption and sequestration and Basidiomycota fungal populations associated with degradation of macromolecules favored the inhibition of soil Cd activity (soil exchangeable Cd decreased by 14.4-14.8% and 18.1-20.6%). This was associated with an increase in organic matter and Si content caused by applying soil conditioners. In conclusion, L-type soil conditioners, rich in Si and organic fertilizer, can reduce soil Cd bioavailability by regulating the dominant Cd passivating flora in the soil and ultimately reduce Cd accumulation in rice.

Understanding the composition and contents of carotenoids in various soybean seed accessions is important for their nutritional assessment.  This study investigated the variability in the concentrations of carotenoids and chlorophylls and revealed their associations with other nutritional quality traits in a genetically diverse set of Chinese soybean accessions comprised of cultivars and landraces.  Genotype, planting year, accession type, seed cotyledon color, and ecoregion of origin significantly influenced the accumulation of carotenoids and chlorophylls.  The mean total carotenoid content was in the range of 8.15–14.72 µg g^–1 across the ecoregions.  The total carotenoid content was 1.2-fold higher in the landraces than in the cultivars.  Soybeans with green cotyledons had higher contents of carotenoids and chlorophylls than those with yellow cotyledons.  Remarkably, lutein was the most abundant carotenoid in all the germplasms, ranging from 1.35–37.44 µg g^–1.  Carotenoids and chlorophylls showed significant correlations with other quality traits, which will help to set breeding strategies for enhancing soybean carotenoids without affecting the other components.  Collectively, our results demonstrate that carotenoids are adequately accumulated in soybean seeds, however, they are strongly influenced by genetic factors, accession type, and germplasm origin.  We identified novel germplasms with the highest total carotenoid contents across the various ecoregions of China that could serve as the genetic materials for soybean carotenoid breeding programs, and thereby as the raw materials for food sectors, pharmaceuticals, and the cosmetic industry.

Carbapenem- and colistin-resistant Enterobacter has been a clinical and therapy problem in recent years. Here, we report the carbapenem- and colistin-resistant Enterobacter harboring bla_IMI isolated from intestinal samples and the environment of a duck farm in China. Four bla_IMI-positive Enterobacter isolates were resistant to carbapenem and colistin. Three bla_IMI subtypes were detected in different molecular categories of Enterobacter. The detection of the various IMI producers highlights the diversity of carbapenemases in a duck farm. Whole-genome Sequencing demonstrated the bla_IMI genes were present in chromosomes or plasmids in these strains. The conjugation experiment demonstrated the ability of bla_IMI-carrying plasmid to transmit horizontally. The molecular evolution characteristics were examined through comparative genetic analysis. The study demonstrated the presence of chromosomal and plasmid bla_IMI and the bla_IMI-carrying plasmid exhibits a horizontal transmission between Enterobacter and Escherichia coli C600. The similar genetic content was discovered between two bla_IMI-16-positive E. asburiae. In addition, a bla_IMI-16-carrying plasmid is an IncFⅠⅠ(Yp) plasmid, and a substantial amount of mobile genetic elements were identified around bla_IMI-16. The IS-like elements and IncFⅠⅠ(Yp) plasmid is significant in the propagation of bla_IMI. Our study provides evidence for the transmission of diverse bla_IMI genes in China and supplies additional reference data for bla_IMI-positive antimicrobial-resistant Enterobacter. Routine surveys of bla_IMI-positive Enterobacter from animal-raising environments must be given more focus.

Theabrownins (TBs) are the characteristic functional and quality components of dark teas such as Pu’er tea and Chin-brick tea.  TBs are a class of water-soluble brown polymers with multi-molecular weight distribution produced by the oxidative polymerisation of tea polyphenols during the fermentation process of dark tea, both enzymatically and non-enzymatically.  TBs have been extracted and purified from dark tea all the time, but the obtained TBs contain heterogeneous components such as polysaccharides and caffeine in the bound state, which are difficult to remove.  The isolation and purification process was tedious and required the use of organic solvents, which made it difficult to industrialise TBs.  In this study, epigallocatechin (EGC), epigallocatechin gallate (EGCG), epigallocatechin gallate (ECG), EGC/EGCG (mass ratio 1:1), EGCG/ECG (mass ratio 1:1), EGC/ECG (mass ratio 1:1) and EGC/EGCG/ECG (mass ratio 1:1:1) as substrates and catalyzed by polyphenol oxidase (PPO) and peroxidase (POD) in turn to produce TBs, named TBs-dE-1, TBs-dE-2, TBs-dE-3, TBs-dE-4, TBs-dE-5, TBs-dE-6 and TBs-dE-7.  The physicochemical properties and the antibacterial activity and mechanism of TBs-dE-1–7 were investigated.  Sensory and colour difference measurements showed that all seven tea browning samples showed varying degrees of brownish hue.  Zeta potential in aqueous solutions at pH 3.0–9.0 indicated that TBs-dE-1–7 was negatively charged and the potential increased with increasing pH.  The characteristic absorption peaks of TBs-dE-1–7 were observed at 208 and 274 nm by UV-visible (UV-vis) scanning spectroscopy.  Fourier transform infrared (FT-IR) spectra indicated that they were phenolic compounds.  TBs-dE-1–7 showed significant inhibition of Escherichia coli DH5α (E. coli DH5α).  TBs-dE-3 showed the strongest inhibitory effect with minimum inhibitory concentration (MIC) of 1.25 mg mL^–1 and MBC of 10 mg mL^–1, followed by TBs-dE-5 and TBs-dE-6.  These three TBs-dEs were selected to further investigate their inhibition mechanism.  The TBs-dE was found to damage the extracellular membrane of E. coli DH5α, causing leakage of contents, and increase intracellular reactive oxygen content, resulting in abnormal cell metabolism due to oxidative stress.  The results of the study provide a theoretical basis for the industrial preparation and product development of TBs.

Nitrogen, phosphorus, and potassium are essential macronutrients crucial not only for maize growth and development, but also for crop yield and quality.  The genetic basis of macronutrient dynamics and accumulation during grain filling in maize remains largely unknown.  In this study, we evaluated grain N, P, and K concentrations in 206 recombinant inbred lines generated from a cross of DH1M and T877 at six time points after pollination.  We then calculated conditional phenotypic values at different time intervals to explore dynamic characteristics of N, P, and K concentrations. Abundant phenotypic variation was observed in the concentration and net changes of these nutrients.  Unconditional quantitative trait locus (QTL) mapping revealed 41 non-redundant QTLs, including 17, 16, and 14 for N, P, and K concentrations, respectively.  Conditional QTL mapping uncovered 39 non-redundant QTLs related to net changes in N, P, and K concentrations.  By combining QTL, gene expression, co-expression analysis, and comparative genomic data, we identified 44, 36, and 44 candidate genes for N, P, and K concentration, respectively, including GRMZM2G371058 encoding a Dof-type zinc finger DNA-binding family protein, associated with N concentration, and GRMZM2G113967 encoding a CBL-interacting protein kinase, related to K concentration.  Our results should deepen understanding of genetic factors controlling N, P, and K accumulation during maize grain development and provide valuable genes for genetic improvement of nutrient concentrations in maize.

The development of receptive endometrium (RE) from pre-receptive endometrium (PE) for successful embryo implantation is a complex dynamic process in which the morphology and physiological states of the endometrial epithelium undergo a series of significant changes, including cell proliferation and apoptosis. However, the molecular mechanisms are not yet fully understood. In this study, a higher circRNA3669 level was observed in PE than in RE of goats. Functional assays revealed that this overexpression promoted the proliferation of goat endometrial epithelial cells (GEECs) by activating the expression of genes related to the PI3K/AKT-mTOR and MAPK pathways, thereby inhibiting apoptosis in vitro. Furthermore, circRNA3669 functioned as a competing endogenous RNA (ceRNA) to upregulate Reticulocalbin-2 (RCN2) expression at the post-transcriptional level by interacting with and downregulating miR-26a in GEECs. In addition, RCN2, which is highly expressed in the PE of goats, was found to be regulated by β-estradiol (E2) and progesterone (P4). Our results demonstrated that RCN2 also affected the key proteins PI3K, AKT, mTOR, JNK, and P38 in the PI3K/AKT-mTOR and MAPK pathways, thereby facilitating GEECs proliferation and suppressing their apoptosis in vitro. Collectively, we constructed a new circRNA3669-miR-26a-RCN2 regulatory network in GEECs, which further provides strong evidence that circRNA could potentially play a crucial regulatory role in the development of RE in goats. 

The two-spotted spider mite, Tetranychus urticae Koch, is one of the most harmful pests in many agroecosystems worldwide. To effectively manage this pest, there is an urgent need to develop novel bio-active acaricides that support integrated pest management strategies targeting T. urticae. In this study, we explored the acaricidal effects of xenocoumacin 1 (Xcn1) on T. urticae and its predator Neoseiulus californicus using the highly purified compound. Xcn1 was extracted and purified from the cell-free supernatant of the Xenorhabdus nematophila CB6 mutant constructed by the easy promoter activated compound identification (easyPACId) method. When the concentration of Xcn1 exceeded 100 μg mL^-1, the survival rate of spider mite adults declined to below 40% and the fecundity was decreased by 80% at six days post application. At concentrations of 25 and 50 μg mL^-1, Xcn1 significantly impeded spider mite development by inhibiting the molt. However, neither concentration had any adverse effects on the survival or reproduction of the predatory mite N. californicus. The results from laboratory and semifield experiments consistently demonstrated the effectiveness of the antimicrobial metabolite Xcn1 in controlling pest mites at both the molecular and physiological levels. Our study offers a promising possibility that combines the compatible biocontrol agents of Xcn1 and predatory mites for integrated pest mite control.

The effect of nitrogen (N) fertilizer on the development of maize kernels has yet to be fully explored.  MicroRNA-mRNA analyses could help advance our understanding of how kernels respond to N.  This study analyzed the morphological, physiological, and transcriptomic changes in maize kernels under different N rates (0, 100, 200, and 300 kg ha^–1).  The result showed that increasing N application significantly increased maize grains’ fresh and dry weight until N reached 200 kg ha^–1.  Higher levels of indole-3-acetic acid, cytokinin, gibberellin, and a lower level of ethylene were associated with increased N applications.  We obtained 31 differentially expressed genes (DEGs) in hormone synthesis and transduction, and 9 DEGs were regulated by 14 differentially expressed microRNAs (DEMIs) in 26 pairs.  The candidate DEGs and DEMIs provide valuable insight for manipulating grain filling under different N rates.

α-Linolenic acid (ALA, 18:3Δ9,12,15) is an essential fatty acid for human, since it is the precursor for the biosynthesis of omega-3 long-chain polyunsaturated fatty acids (LC-PUFA).  Modern people generally suffer from deficiency of ALA, since most staple food oils are low or lack in ALA content.  Biotechnological enrichment of ALA in staple oil crops is a promising strategy.  Among known oil crops, chia (Salvia hispanica) has the highest ALA content in its seed oil.  In this study, the FAD2 and FAD3 genes from chia were engineered into a staple oil crop, oilseed rape (Brassica napus), via Agrobaterium tumefaciens-mediated transformation of their LP4-2A fusion gene construct driven by the seed-specific promoter P_NapA.  In seeds of T0, T1 and T2 lines, the average ALA contents were 20.86, 23.54 and 24.92%, which were 2.21, 2.68 and 3.03 folds of the non-transformed controls (9.42, 8.78 and 8.22%), respectively.  The highest ALA levels of seeds of T0, T1 and T2 plants, were 38.41, 35.98 and 39.19% respectively, which were 4.10-4.77 folds of the respective controls.  FA-pathway enzyme genes BnACCD, BnFATA, BnSAD, BnSCD, BnDGAT1, BnDGAT2 and BnDGAT3 as well as positive regulatory genes BnWRI1, BnLEC1, BnL1L, BnLEC2, BnABI3, BnbZIP67 and BnMYB96 were all significantly up-regulated.  In contrast, BnTT1, BnTT2, BnTT8, BnTT16, BnTTG1 and BnTTG2, encoding negative regulators of oil accumulation but positive regulators of secondary metabolism, were all significantly down-regulated.  These mean that foreign ShFAD2-ShFAD3 fusion gene directly and indirectly remodeled both positive and negative loci of the whole FA-related network in transgenic B. napus seeds.

Propylea japonica (Coleoptera: Coccinellidae) is a natural enemy insect with a wide range of predation in mainland China and is commonly used in pest management. However, its genetic pattern (i.e., genetic variation, genetic structure, and historical population dynamics) is still unclear, impeding the development of biological control of insect pests. Population genetic research has the potential to optimize strategies at different stages of the biological control processes. This study used 23 nuclear microsatellite sites and mitochondrial COI genes to investigate the population genetics of Propylea japonica based on 462 specimens collected from 30 sampling sites in China. The microsatellite dataset showed a moderate level of genetic diversity, but the mitochondrial genes showed a high level of genetic diversity. Populations from the Yellow River basin were more genetically diverse than those in the Yangtze River basin. P. japonica has not yet formed a significant geographically genealogical structure in China, but there was a population structure signal to some extent, which may be caused by frequent gene flow between populations. The species has experienced population expansion after a bottleneck, potentially thanks to the tri-trophic plant-insect-natural enemy relationship. Knowledge of population genetics is of importance in using predators to control pests. Our study complements existing knowledge of an important natural predator in agroecosystems through estimating its genetic diversity and population differentiation and speculating about historical dynamics.

As there is a strong interest in red-skinned pears, the molecular mechanism of anthocyanin regulation in red-skinned pears has been widely investigated; however, little is known about the molecular mechanism of anthocyanin regulation in red-fleshed pears due to limited availability of such germplasm, primarily found in European pears (Pyrus communis).  In this study, based on transcriptomic analysis in red-fleshed and white-fleshed pears, we identified an ethylene response factor (ERF) from P. communis, PcERF5, of which expression level in fruit flesh was significantly correlated with anthocyanin content.  We then verified the function of PcERF5 in regulating anthocyanin accumulation by genetic transformation in both pear skin and apple calli.  PcERF5 regulated anthocyanin biosynthesis by different regulatory pathways.  On the one hand, PcERF5 can activate the transcription of flavonoid biosynthetic genes (PcDFR, PcANS and PcUFGT) and two key transcription factors encoding genes PcMYB10 and PcMYB114.  On the other hand, PcERF5 interacted with PcMYB10 to form the ERF5-MYB10 protein complex that enhanced the transcriptional activation of PcERF5 on its target genes.  Our results suggested that PcERF5 functioned as a transcriptional activator in regulating anthocyanin biosynthesis, which provides new insights into the regulatory mechanism of anthocyanin biosynthesis.  This new knowledge will provide guidance for molecular breeding of red-fleshed pear.

Sugar is an indispensable source of energy for plant growth and development, and it requires the participation of sugar transporter proteins (STPs) for crossing the hydrophobic barrier in plants.  Here, we systematically identified the genes encoding sugar transporters in the genome of maize (Zea mays L.), analyzed their expression patterns under different conditions, and determined their functions in disease resistance.  The results showed that the mazie sugar transporter family contained 24 members, all of which were predicted to be distributed on the cell membrane and had a highly conserved transmembrane transport domain.  The tissue-specific expression of the maize sugar transporter genes was analyzed, and the expression level of these genes was found to be significantly different in different tissues.  The analysis of biotic and abiotic stress data showed that the expression levels of the sugar transporter genes changed significantly under different stress factors.  The expression levels of ZmSTP2 and ZmSTP20 continued to increase following Fusarium graminearum infection.  By performing disease resistance analysis of zmstp2 and zmstp20 mutants, we found that after inoculation with Cochliobolus carbonum, Setosphaeria turcica, Cochliobolus heterostrophus, and F. graminearum, the lesion area of the mutants was significantly higher than that of the wild-type B73 plant.  In this study, the genes encoding sugar transporters in maize were systematically identified and analyzed at the whole genome level.  The expression patterns of the sugar transporter-encoding genes in different tissues of maize and under biotic and abiotic stresses were revealed, which laid an important theoretical foundation for further elucidation of their functions.

The Internet is believed to bring more technological dividends to vulnerable farmers during the green agriculture transformation.  However, this is different from the theory of skill-biased technological change, which emphasizes that individuals with higher levels of human capital and more technological endowments benefit more.  This study investigates the effects of Internet use on farmers’ adoption of integrated pest management (IPM), theoretically and empirically, based on a dataset containing 1 015 farmers in China’s Shandong Province.  By exploring the perspective of rational inattention, the reasons for the heterogeneity of the effects across farmers with different endowments, i.e., education and land size, are analyzed.  The potential endogeneity issues are addressed using the endogenous switching probit model.  The results reveal that: (1) although Internet use significantly positively affects farmers’ adoption of IPM, vulnerable farmers do not benefit more from it.  Considerable selection bias leads to an overestimation of technological dividends for vulnerable farmers; (2) different sources of technology information lead to the difference in the degree of farmers’ rational inattention toward Internet information, which plays a crucial role in the heterogeneous effect of Internet use; and (3) excessive dependence on strong-tie social network information sources entraps vulnerable farmers in information cocoons, hindering their ability to reap the benefits of Internet use fully.  Therefore, it is essential to promote services geared towards elderly-oriented Internet agricultural technology information and encourage farmers with strong Internet utilization skills to share technology information with other farmers actively.

The oriental fruit fly, Bactrocera dorsalis (Hendel), is a devastating pest of citrus fruits.  After successful mating, adult females insert their eggs into the ripened fruit, resulting in moldy and rotten fruit and causing great economic losses for the citrus industry.  In the field, flies initiate copulatory behaviors as twilight approaches, and decreasing light intensity in this period is the normal stimulus for copulation.  In this study, ten light intensities ranging from 0–30 000 lux were set to identify the typical intensity that strongly regulates the copulation behavior of B. dorsalis.  Three light intensities found to regulate the copulation behavior were then selected to verify their effects on adult male wing fanning and female chemotaxis towards 2,3,5-trimethylpyrazine (TMP).  At last, strong light and complete darkness were artificially combined in the lab to verify whether they could prevent copulation to inform behavioral manipulation of oriental flies in the future.  The results indicated that adult flies generally initiated copulatory behaviors at low light intensity (<1 000 lux).  
Stronger light significantly prevented copulation in proportion to intensity, with nearly no copulation events initiated when light intensity was above 20 000 lux.  Both male wing fanning and female chemotaxis towards TMP were attenuated as light intensity became stronger.  However, at 10 000 lux, males still fanned their wings to a certain extent while TMP completely lost its attractiveness to females.  In the darkness, adults did not initiate any sexual behaviors, e.g., copulation, wing fanning, or chemotaxis to TMP.  One hour of strong light (10 000 lux) combined with continuous darkness completely prevented mating.  These results show that light condition is an essential factor for copulatory behaviors in the oriental fruit fly.  Researchers could thus manipulate light conditions artificially or disrupt the molecular target in flies’ light transduction pathway to develop environmentally-friendly techniques to control this pest.

Canopy temperature, which strongly influences crop yield formation, is closely related to plant physiological traits.  However, the effects of nitrogen treatment on canopy temperature and rice growth have not been comprehensively examined.  We conducted a two-year field experiment with three rice varieties (HD-5, NJ-9108, and YJ-805) and three nitrogen treatments (i.e., zero-N control (CK), 200 kg ha^–1 (MN), and 300 kg ha^–1 (HN)).  We measured canopy temperature using a drone equipped with a high-precision camera at the six stages of the growth period.  Generally, canopy temperature was found to be significantly higher for CK than for MN and HN during the tillering, jointing, booting, and heading stages.  The temperature was not found to be significantly different among the nitrogen treatments between the milky and waxy stages.  The canopy temperature of different rice varieties was found to follow the order: HD-5>NJ-9108>YJ-805, but the difference was not significant.  The canopy temperature of rice was mainly related to plant traits, such as shoot fresh weight (correlation coefficient r=-0.895), plant water content (-0.912), net photosynthesis (-0.84), stomatal conductance (-0.91), transpiration rate (-0.90), and leaf stomatal area (-0.83).  A structural equation model (SEM) showed that nitrogen fertilizer was an important factor affecting the rice canopy temperature.  Our study revealed that: (1) a suite of plant traits was associated with the nitrogen effects on canopy temperature, (2) the heading stage was the best time to observe rice canopy temperature, and (3) at that stage, canopy temperature was negatively correlated with rice yield, panicle number, and grain number per panicle.  This study provides that canopy temperature may be a convenient and accurate indicator of rice growth and yield prediction.

Actinidia eriantha is one of the species of kiwifruit with a particularly high ascorbic acid (AsA) content.  However, the molecular mechanism driving AsA richness in fruit remains unclear.  In order to reveal the molecular mechanism of AsA richness in A. eriantha, this study constructed a regulatory network related to AsA metabolism by combining genomics, metabolomics and transcriptomics.  We assembled a high-quality genome of A. eriantha ‘Ganlv 1’ with only five remaining gaps.  The assembly is comprised of 29 pseudochromosomes with a total size of 615.95 Mb, and contig N50 of 20.35 Mb. Among them, 24 of the pseudochromosomes were obtained directly from telomere-to-telomere.  The LTR assembly index score and consensus quality value were 21.34 and 39.90%, respectively.  Subsequently, 61 metabolites and 2 092 genes were found to be differentially accumulated/expressed during fruit development by metabolome and transcriptome assays, respectively.  AsA metabolism and the cyclic regeneration pathway were found to have high expression levels throughout fruit growth and development, suggesting its crucial role in the regulation of AsA.  Furthermore, the AsA contents are highly associated with ascorbate peroxidase genes.  The genome obtained in this study provides genomic resources for the genetic and breeding research of A. eriantha, and the constructed regulatory network can provide a public data platform for future research on kiwifruit.

A recent article describes the identification of a new allele of Gγ which is involved in yield promotion and alkaline tolerance in four major monocot crops, including sorghum, rice, maize and millet.  The research team also demonstrated the role of that same allele in wheat under alkaline stress.  These studies may provide a new avenue for improving crop production and alkaline stress tolerance in several important crops. 

Citrus yellow mottle-associated virus (CiYMaV) belonging to the subgenus Mandarivirus within the genus Potexvirus, was first identified in 2018 from Pakistan (CiYMaV-PK), where it is endemic in several regions.  Here, three full-length cDNA clones (pCiYMaV-FL-1, pCiYMaV-FL-18, and pCiYMaV-FL-22) corresponding to the genomic RNA of CiYMaV were constructed and then agroinfiltrated on Chandler pummelo (Citrus grandis) seedlings using the vacuum infiltration method.  All the inoculated plants developed severe vein yellowing, leaf mottling, and dwarfing symptoms by 40 days post-infiltration (dpi).  The results of a direct tissue blot immunoassay and reverse transcription polymerase chain reaction detection showed 94.7–100% infection rates of pCiYMaV-FL at 60 dpi.  Despite there being no observed difference among the three clones in the severity of symptom, pCiYMaV-FL-22 showed the highest accumulation levels of viral RNA and coat proteins.  Moreover, pCiYMaV-FL-22 successfully infected seven other citrus varieties and induced symptoms in five of them.  Transmission electron microscopy identified the presence of filamentous virus particles in extracts from systemic leaves of the plants infected with pCiYMaV-FL-22 at 6-months post-infiltration.  Taken together, the results indicate that Koch’s postulates were fulfilled for CiYMaV in citrus plants.  This is the first report of full-length infectious cDNA clones of CiYMaV, and thus, the data provide a basis for further study of the molecular mechanisms of virus infection and the development of a viral vector to express foreign genes in citrus plants.

Avian infectious bronchitis (IB) is a highly contagious infectious disease caused by infectious bronchitis virus (IBV), which is prevalent in many countries worldwide and causes serious harm to the poultry industry.  At present, many commercial IBV vaccines have been used for the prevention and control of IB; however, IB outbreaks occur frequently.  In this study, two new strains of IBV, SX/2106 and SX/2204, were isolated from two flocks which were immunized with IBV H120 vaccine in central China.  Phylogenetic and recombination analysis indicated that SX/2106, which was clustered into the GI-19 lineage, may be derived from recombination events of the GI-19 and GI-7 strains and the LDT3-A vaccine.  Genetic analysis showed that SX/2204 belongs to the GVI-1 lineage, which may have originated from the recombination of the GI-13 and GVI-1 strains and the H120 vaccine.  The virus cross-neutralization test showed that the antigenicity of SX/2106 and SX/2204 was different from H120.  Animal experiments found that both SX/2106 and SX/2204 could replicate effectively in the lungs and kidneys of chickens and cause disease and death, and H120 immunization could not provide effective protection against the two IBV isolates.  It is noteworthy that the pathogenicity of SX/2204 has significantly increased compared to the GVI-1 strains isolated previously, with a mortality rate up to 60%.  Considering the continuous mutation and recombination of the IBV genome to produce new variant strains, it is important to continuously monitor epidemic strains and develop new vaccines for the prevention and control of IBV epidemics.

 Delays in sowing have significant effects on grain yield, yield components, and grain protein concentrations of winter wheat.  However, little is known about how delayed sowing affects these characteristics at different positions in wheat spikes.  In this study, the effects of sowing date were investigated in a winter wheat cultivar, Shannong 30, which was sown in 2019 and 2020 on October 8 (normal sowing) and October 22 (late sowing) under field conditions.  Delayed sowing increased the partitioning of ¹³C-assimilates to spikes, particularly to florets at the apical section of a spike and those occupying distal positions on the same spikelet.  Consequently, the increase in grain number was greatest for apical sections, followed by the basal and central sections.  No significant differences were observed in superior grain number in the basal and central sections between sowing dates, while the number in apical sections was significantly different.  The number of inferior grains in each section also substantially increased in response to delayed sowing.  Average grain weight in all sections remained unchanged under delayed sowing because there was a parallel increase in grain number and ¹³C-assimilate partitioning to grains at specific positions in the spikes.  Increases in grain number m^-2 resulted in reduced grain protein concentration as the limited nitrogen supply was diluted into more grains.  Delayed sowing caused the greatest decrease in grain protein concentration in basal sections, followed by the central and apical sections.  No significant differences in the reduction in grain protein concentration were observed between inferior and superior grains under delayed sowing.  In conclusion, a 2-week delay in sowing improved grain yield through increased grain number per spike, which originated principally from increased grain number in the apical sections of spikes and in distal positions on the same spikelet.  However, grain protein concentrations decreased in each section because of increased grain number and reduced N uptake.

Enhancing photosynthetic efficiency is a major goal for improving crop yields under agricultural field conditions and is associated with chloroplast biosynthesis and development.  In this study, we demonstrate that Golden2-like 1a (BnGLK1a) plays an important role in regulating chloroplast development and photosynthetic efficiency.  Overexpressing BnGLK1a resulted in significant increases in chlorophyll content, the number of thylakoid membrane layers and photosynthetic efficiency in Brassica napus, while knocking down BnGLK1a transcript levels through RNA interference (RNAi) had the opposite effects.  A yeast two-hybrid screen revealed that BnGLK1a interacts with the abscisic acid receptor PYRABACTIN RESISTANCE 1-LIKE 1–2 (BnPYL1–2) and CONSTITUTIVE PHOTOMORPHOGENIC 9 SIGNALOSOME 5A subunit (BnCSN5A), which play essential roles in regulating chloroplast development and photosynthesis.  Consistent with this, BnGLK1a-RNAi lines of B. napus display hypersensitivity to the abscisic acid (ABA) response.  Importantly, overexpression of BnGLK1a resulted in a 10% increase in thousand-seed weight, whereas seeds from BnGLK1a-RNAi lines were 16% lighter than wild type.  We propose that BnGLK1a could be a potential target in breeding for improving rapeseed productivity.  Our results not only provide insights into the mechanisms of BnGLK1a function, but also offer a potential approach for improving the productivity of Brassica species.

Fruit development and ripening is a complex procedure (Malus×domestica Borkh.) and can be caused by various factors such as cell structure, cell wall components, and cell wall hydrolytic enzymes.  In our study, we focused on the variations in fruit firmness, cell wall morphology and components, the activity of cell wall hydrolytic enzymes and the expression patterns of associated genes during fruit development in two different types of apple cultivars, the hard-crisp cultivar and the loose-crisp cultivar.  In this paper, the aim was to find out the causes of the texture variations between the different type cultivars.  Cell wall materials (CWMs), hemicellulose and cellulose content were strongly associated with variations in fruit firmness during the fruit development.  The content of water soluble pectin (WSP) and chelator soluble pectin (CSP) gradually increased, while the content of ionic soluble pectin (ISP) showed inconsistent trends in the four cultivars.  The activities of polygalacturonase (PG), β-galactosidase (β-gal), cellulase (CEL), and pectate lyase (PL) gradually increased in four cultivars.  And the activities of PG, β-gal, and CEL were higher in ‘Fuji’ and ‘Honeycrisp’ fruit with the fruit development, while the activity of PL of ‘Fuji’ and ‘Honeycrisp’ was lower than that of ‘ENVY’ and ‘Modi’.  Both four cultivars of fruit cells progressively became bigger as the fruit expanded, with looser cell arrangements and larger cell gaps.  According to the qRT-PCR, the relative expression levels of MdACO and Mdβ-gal were notably enhanced.  Our study showed that there were large differences in the content of ISP and hemicellulose, the activity of PL and the relative expression of Mdβ-gal between two different types of apple cultivars, and these differences might be responsible for the variations in the texture of the four cultivars.

The physiological and metabolic differences in maize under different nitrogen (N) levels are the basis of reasonable N management, which is vital in improving fertilizer utilization and reducing environmental pollution.  In this paper, on the premise of defining the N fertilizer efficiency and yield under different long-term N fertilization treatments, the corresponding differential metabolites and their metabolic pathways were analyzed by untargeted metabolomics in maize.  N stress, including deficiency and excess, affects the balance of carbon (C) metabolism and N metabolism by regulating C metabolites (sugar alcohols and tricarboxylic acid (TCA) cycle intermediates) and N metabolites (various amino acids and their derivatives).  L-alanine, L-phenylalanine, L-histidine, and L-glutamine decreased under N deficiency, and L-valine, proline, and L-histidine increased under N excess.  In addition to sugar alcohols and the above amino acids in C and N metabolism, differential secondary metabolites, flavonoids (e.g., kaempferol, luteolin, rutin, and diosmetin), and hormones (e.g., indoleacetic acid, trans-zeatin, and jasmonic acid) were initially considered as indicators for N stress diagnosis under this experimental conditions.  This study also indicated that the leaf metabolic levels of N2 (120 kg ha^–1 N) and N3 (180 kg ha^–1 N) were similar, consistent with the differences in their physiological indexes and yields over 12 years.  This study verified the feasibility of reducing N fertilization from 180 kg ha^–1 (locally recommended) to 120 kg ha^–1 at the metabolic level, which provided a mechanistic basis for reducing N fertilization without reducing yield, further improving the N utilization rate and protecting the ecological environment.

As important yield-related traits, thousand-grain weight (TGW), grain number per spike (GNS) and grain weight per spike (GWS) are crucial components of wheat production.  To dissect their underlying genetic basis, a double haploid (DH) population comprised of 198 lines derived from 8762/Keyi 5214 was constructed.  We then used genechip to genotype the DH population and integrated the yield-related traits TGW, GNS and GWS for QTL mapping.  Finally, we obtained a total of 18 942 polymorphic SNP markers and identified 41 crucial QTLs for these traits.  Three stable QTLs for TGW were identified on chromosomes 2D (QTgw-2D.3 and QTgw-2D.4) and 6A (QTgw-6A.1), with additive alleles all from the parent 8762, explaining 4.81–18.67% of the phenotypic variations.  Five stable QTLs for GNS on chromosomes 3D, 5B, 5D and 6A were identified.  QGns-5D.1 was from parent 8762, while the other four QTLs were from parent Keyi 5214, explaining 5.89–7.08% of the GNS phenotypic variations.  In addition, a stable GWS genetic locus QGws-4A.3 was detected from the parent 8762, which explained 6.08–6.14% of the phenotypic variations.  To utilize the identified QTLs, we developed STARP markers for four important QTLs, Tgw2D.3-2, Tgw2D.4-1, Tgw6A.1 and Gns3D.1.  Our results provide important basic resources and references for the identification and cloning of genes related to TGW, GNS and GWS in wheat.

Climate change which is mainly caused by carbon emissions is a global problem affecting the economic development and well-being of human society. Low-carbon agriculture is of particular significance in slowing down global warming and reaching the goal of “carbon peak and carbon neutrality”. Therefore, taking straw incorporation as an example, this paper aims to investigate the impact of risk preferences on farmers’ low-carbon agricultural technology (LCAT) adoption. Based on a two-phase micro-survey data of 1,038 rice farmers in Jiangsu, Jiangxi, and Hunan provinces, this paper uses experimental economics methods to measure farmers’ risk aversion and loss aversion to obtain the real risk preferences information of the farmers. We also explore the data to examine the actual LCAT adoption behavior of farmers. The results revealed that both risk aversion and loss aversion significantly inhibit farmers’ LCAT adoption: more risk averse or more loss averse farmers are less likely to adopt LCAT. It is further found that crop insurance, farm scale and governmental regulations can alleviate the negative impact of risk aversion and loss aversion on farmers’ LCAT adoption. Therefore, we propose that local governments need to promote low-carbon agricultural development by propagating the benefits of LCAT, extending crop insurance, promoting appropriate scale operations, and strengthening governmental regulations to promote farmers’ LCAT adoption.

The paper reviews studies of rural transformation in three dimensions – definition, measurement, and indicators – and summarises the findings of rural transformation research. The scope of rural transformation includes four elements – productivity, rurality, inclusiveness, and sustainability. Current concepts of the dimensions of rural transformation and their associated indicators are insufficient for policy decision-making, as they lack objectivity, feasibility, accountability, comprehensiveness, and comparability. Future research to develop new measures to assess rural transformation in developing countries is valuable. Furthermore, there is potential to explore the topic in some directions: urbanisation strategy, public intervention (i.e., institution, policy, and investment), gender inclusiveness, market creation, and international trade.

Rhododendron is a well-known genus consisting of commercially valuable ornamental woody plant species. Heat stress is a major environmental factor that affects rhododendron growth. Melatonin was recently reported to alleviate the effects of abiotic stress on plants. However, the role of melatonin in rhododendron plants is unknown. In this study, the effect of melatonin on rhododendron plants exposed to heat stress and the potential underlying mechanism were investigated. Analyses of morphological characteristics and chlorophyll a fluorescence indicated 200 µmol L^-1 was the optimal melatonin concentration for protecting rhododendron plants from heat stress. To elucidate how melatonin limits the adverse effects of high temperatures, melatonin contents, photosynthetic indices, Rubisco activity, and ATP contents were analyzed at 25, 35, and 40°C. Compared with the control, exogenous application of melatonin improved the melatonin contents, electron transport rate, photosystem II and I activities, Rubisco activity, and ATP contents under heat stress. The transcriptome analysis revealed many of the heat-induced differentially expressed genes were associated with the photosynthetic pathway; the expression of most of these genes was down-regulated by heat stress more in the melatonin-free plants than in the melatonin-treated plants. We identified RhPGR5A, RhATPB, RhLHCB3, and RhRbsA as key genes. Thus, we speculate that melatonin promotes photosynthetic electron transport, improves Calvin cycle enzyme activities, and increases ATP production. These changes lead to increased photosynthetic efficiency and CO₂ assimilation under heat stress conditions via the regulated expression of specific genes, including RhRbsA. Therefore, the application of exogenous melatonin may increase the tolerance of rhododendron to heat stress.

Improving soil quality while achieving higher productivity is the major challenge in the agricultural industry.  Wheat (Triticum aestivum L.)–maize (Zea mays L.) (W–M) rotation is the dominant planting pattern in the Huang-Huai-Hai  Plain and is important for food security in China.  However, the soil quality is deteriorating due to the W–M rotation’s long-term, intensive, and continuous cultivation.  Introducing legumes into the W–M rotation system may be an effective way to improve soil quality.  In this study, we aimed to verify this hypothesis by exploring efficient planting systems (wheat–peanut (Arachis hypogaea L.) (W–P) rotation and wheat rotated with maize and peanut intercropping (W–M/P)) to achieve higher agricultural production in the Huang-Huai-Hai   Plain.  Using traditional W–M rotation as the control, we evaluated crop productivity, net returns, soil microorganisms (SMs), and soil organic carbon (SOC) fractions for three consecutive years.  The results indicated that wheat yields were significantly increased under W–P and W–M/P (382.5–579.0 and 179.8–513.1 kg ha⁻¹, respectively) compared with W–M.  W–P

and W–M/P provided significantly higher net returns (58.2 and 70.4%, respectively) than W–M.  W–M/P and W–M retained the SOC stock more efficiently than W–P, increasing by 25.46–31.03 and 14.47–27.64%, respectively, in the 0–20 cm soil layer.  Compared with W–M, W–M/P improved labile carbon fractions; the sensitivity index of potentially mineralizable carbon, microbial biomass carbon (MBC), and dissolved organic carbon was 31.5, 96.5–157.2, and 17.8% in 20–40, 10–40, and 10–20 cm soil layers, respectively.  The bacterial community composition and bacteria function were altered as per the soil depth and planting pattern.  W–M/P and W–M exhibited similar bacterial community composition and function in 0–20 and 20–40 cm soil layers.  Compared with W–P, a higher abundance of functional genes, namely, contains mobile elements and stress-tolerant, and a lower abundance of genes, namely, potentially pathogenic, were observed in the 10–20 cm soil layer of W–M and the 0–20 cm soil layer of W–M/P.  SOC and MBC were the main factors affecting soil bacterial communities, positively correlated with Sphingomonadales and Gemmatimonadales and negatively correlated with Blastocatellales.  Organic input was the main factor affecting SOC and SMs, which exhibited feedback effects on crop productivity.  In summary, W–M/P improved productivity, net returns, and SOC pool compared with traditional W–M rotation systems, and it is recommended that plant–soil–microbial interactions be considered while designing high-yield cropping systems.

Numbers of vertebrae is an important economic trait associated with body size and meat productivity in animals.  However, the genetic basis of vertebrae number in donkey remains to be well understood.  The aim of this study was to identify candidate genes affecting the number of thoracic (TVn) and the number of lumbar vertebrae (LVn) in Dezhou donkey.  A genome-wide association study was conducted using whole genome sequence data imputed from low-coverage genome sequencing.  For TVn, we identified 38 genome-wide significant and 64 suggestive SNPs, which relate to 7 genes (NLGN1, DCC, SLC26A7, TOX, WNT7A, LOC123286078, and LOC123280142).  For LVn, we identified 9 genome-wide significant and 38 suggestive SNPs, which relate to 8 genes (GABBR2, FBXO4, LOC123277146, LOC123277359, BMP7, B3GAT1, EML2, and LRP5).  The genes involve in the Wnt and TGF-β signaling pathways and may play an important role in embryonic development or bone formation and could be good candidate genes for TVn and LVn.

Flower organ identity in rice is mainly determined by A-, B-, C- and E-class genes, with the majority encoding MADS-box transcription factors.  However, few studies have investigated how the expression of these floral organ identity genes is regulated during flower development.  In this study, we identified a gene named SUPER WOMAN 2 (SPW2), which is necessary for spikelet/floret development in rice by participating in the expression regulation of pistil identity genes such as OsMADS3, OsMADS13, OsMADS58 and DL.  In spw2 mutant, ectopic stigma/ovary-like tissues have been observed in the non-pistil organs, including sterile lemma, lemma, palea, lodicule, and stamen, suggesting that identities of these organs were severely affected by mutations in SPW2. SPW2 encoded a plant-specific EMF1-like protein that involved in the H3K27me3 modification as an important component of the PRC2 complex.  Expression analysis showed that the SPW2 mutation led to the ectopic expression of OsMADS3, OsMADS13, OsMADS58, and DL in non-pistil organs of the spikelet.  The ChIP-qPCR results showed a significant decrease in the levels of H3K27me3 modification on the chromatin of these genes.  Thus, we demonstrated that SPW2 can mediate the process of H3K27me3 modification of pistil-related genes to regulate their expression in non-pistil organs of spikelets in rice.  This study expands our understanding of the molecular mechanism by which SPW2 regulates floral organ identity genes through epigenetic regulation.

The application of a male-sterile line is an ideal approach for hybrid seed production in non-heading Chinese cabbage (Brassicarapa ssp. chinensis).  However, the molecular mechanisms underlying male sterility in B.rapa are still largely unclear.  We previously obtained the natural male sterile line WS24-3 of non-heading Chinese cabbage and located the male sterile locus, Bra2Ms, on the A2 chromosome.  Cytological observations revealed that the male sterility of WS24-3 resulted from disruption of the meiosis process during pollen formation.  Fine mapping of Bra2Ms delimited the locus within a physical distance of about 129 kb on the A2 chromosome of B. rapa.  The Bra039753 gene encodes a plant homeodomain (PHD)-finger protein and is considered a potential candidate gene for Bra2Ms.  Bra039753 was significantly downregulated in sterile line WS24-3 compared to the fertile line at the meiotic anther stage.  Sequence analysis of Bra039753 identified a 369 bp fragment insertion in the first exon in male sterile plants, which led to an amino acid insertion in the Bra039753 protein.  In addition, the 369 bp fragment insertion was found to cosegregate with the male sterility trait.  This study identified a novel locus related to male sterility in non-heading Chinese cabbage, and the molecular marker obtained in this study will be beneficial for the marker-assisted selection of excellent sterile lines in non-heading Chinese cabbage and other Brassica crops.

Bacteria play critical roles in regulating soil phosphorus (P) cycling.  The effects of interactions between crops and soil P-availability on bacterial communities and the feedback regulation of soil P cycling by the bacterial community modifications are poorly understood.  Here, six soybean (Glycinemax) genotypes with differences in P efficiency were cultivated in acidic soils with long-term sufficient or deficient P-fertilizer treatments.  The acid phosphatase (AcP) activities, organic-P concentrations and associated bacterial community compositions were determined in bulk and rhizosphere soils.  The results showed that both soybean plant P content and the soil AcP activity were negatively correlated with soil organic-P concentration in P-deficient acidic soils.  Soil P-availability affected the ɑ-diversity of bacteria in both bulk and rhizosphere soils.  However, soybean had a stronger effect on the bacterial community composition, as reflected by the similar biomarker bacteria in the rhizosphere soils in both P-treatments.  The relative abundance of biomarker bacteria Proteobacteria was strongly correlated with soil organic-P concentration and AcP activity in low-P treatments.  Further high-throughput sequencing of the phoC gene revealed an obvious shift in Proteobacteria groups between bulk soils and rhizosphere soils, which was emphasized by the higher relative abundances of Cupriavidus and Klebsiella, and lower relative abundance of Xanthomonas in rhizosphere soils.  Among them, Cupriavidus was the dominant phoC bacterial genus, and it was negatively correlated with the soil organic-P concentration.  These findings suggest that soybean growth relies on organic-P mineralization in P-deficient acidic soils, which might be partially achieved by recruiting specific phoC-harboring bacteria, such as Cupriavidus.

The practice of intercropping leguminous and gramineous crops is used for promoting sustainable agriculture, optimizing resource utilization, enhancing biodiversity, and reducing reliance on petroleum products.  However, promoting conventional intercropping strategies in modern agriculture can prove challenging.  The innovative technology of soybean maize strip intercropping (SMSI) has been proposed as a solution.  This system has produced remarkable results in improving domestic soybean and maize production for both food security and sustainable agriculture.  In this article, we provide an overview of SMSI and explain how it differs from traditional intercropping.  We also discuss the core principles that foster higher yields and the prospects for its future development.

In this research, green synthesized magnesium oxide nanoparticles (MgO NPs) from lemon fruit extracts and their fungicidal potential was evaluated against Alternaria dauci infection on carrot (Daucus carota L.) under greenhouse conditions.  The scanning and transmission electron microscopy (SEM and TEM) and ultra-violet (UV) visible spectroscopy were used to validate and characterize MgO NPs.  The crystalline nature of MgONPs was determined using selected area electron diffraction (SAED).  MgO NPs triggered substantial antifungal activity against A. dauci when exposed to 50 and 100 mg L^–1 concentrations but the higher antifungal potential was noticed in 100 mg L^–1 under in-vitro conditions.  In fungal inoculated plants, a marked decrease in growth, photosynthetic pigments, and an increase in phenol, proline contents, and defense-related enzymes of carrot were seen over control (distilled water).  However, foliar application of MgO NPs at 50 and 100 mg L^–1 resulted in significant improvement of plant growth, photosynthetic pigments, phenol and proline contents, and defense enzymes activity of carrots with and without A. dauci infection.  Spraying of MgO NPs at 100 mg L^–1 had more plant length (17.11%), shoot dry weight (34.38%), plant fresh weight (20.46%), and root dry weight (49.09%) in carrots when challenged with A. dauci over inoculated control.  The leaf blight indices and percent disease severity were also reduced in A. dauci inoculated plants when sprayed with MgO NPs.  The non-bonding interactions of Alternaria genus protein with nanoparticles were studied using molecular docking.

Plant-mediated RNA interference (RNAi) has emerged as a promising technology for insect control. The green peach aphid, Myzus persicae, feeds on over 400 species of host plants. Brassica napus (rape) is the second most important oilseed crop worldwide. M. persicae is highly reproductive and causes severe damage to the rape plants due to its quite flexible life cycle. In this study, we tested the RNAi effects of transgenic rape plants on M. persicae. By in-vitro feeding M. persicae with artificial diets containing double-stranded RNAs (dsRNAs) targeting seven aphid genes, we identified a new gene encoding the partitioning-defective protein 6 (Par6) as the most potent RNAi target. Tissue- and stage-expression analysis of Par6 suggested this gene is highly expressed in the embryo and adult stage of M. persicae. We next generated transgenic rape plants expressing dsPar6 by Agrobacterium-mediated transformation and obtained nine independent transgenic lines. Compared to wild-type control plants, transgenic rape lines expressing dsPar6 showed strong resistance to M. persicae. Feeding assays revealed that feeding transgenic rape plants to M. persicae significantly decreased MpPar6 expression and survival rate and impaired fecundity. Furthermore, we showed that the resistance levels to M. persicae are positively correlated with dsPar6 expression levels in transgenic rape plants. Our study demonstrates that transgenic rape plants expressing dsPar6 are efficiently protected from M. persicae. Interfering with the genes involved in embryo development could be the effective RNAi targets for controlling aphids and potentially other insect pests.

Global climate change is characterized by asymmetric warming (i.e., greater temperature increases in winter, spring, and nighttime than in summer, autumn, and daytime).  Field experiments were conducted using four wheat cultivars, namely ‘Yangmai 18’ (YM18), ‘Sumai 188’ (SM188), ‘Yannong 19’ (YN19), and ‘Annong 0711’ (AN0711), in the two growing seasons of 2019–2020 and 2020–2021, with passive night warming during different periods in the early growth stage.  The treatments were night warming during the tillering–jointing (NW_T-J), jointing–booting (NW_J-B), and booting–anthesis (NW_B-A) stages, with ambient temperature (NN) as the control.  The effects of night warming during different stages on wheat yield formation were investigated by determining the characteristics of dry matter accumulation and translocation, as well as sucrose and starch accumulation in wheat grains.  The wheat yield of all four cultivars were significantly higher in NW_T-J than in NN in the 2-year experiment.  The yield increases of semi-winter cultivars YN19 and AN0711 were greater than those of spring cultivars YM18 and SM188.  NW_T-J increased wheat yield mainly by increasing the 1000-grain weight and the number of fertile spikelets. NW_T-J increased dry matter accumulation in various organs of wheat at the anthesis and maturity stages by increasing the growth rate at the vegetative growth stage.  The flag leaf and spike showed the largest increases in dry matter accumulation.  NW_T-J also increased grain sucrose and starch content in the early and middle grain-filling stages, promoting yield formation.  Overall, night warming between the tillering and jointing stages increased the pre-anthesis growth rate, and thus, wheat dry matter production, which contributed to the increase in wheat yield.

Tea is one of the most popular non-alcoholic beverages in the world, and free amino acids, especially theanine, make a major contribution to the umami taste of tea.  However, the genetic basis of the variation in amino acid content in tea plants remains largely unknown.  Here, we measured the free amino acid content in fresh leaves of 174 tea accessions over two years using a targeted metabolomics approach and obtained genotype data via RNA sequencing.  Genome-wide association studies were conducted to investigate loci affecting the content of free amino acids.  A total of 69 quantitative trait loci (–log₁₀(P-value)>5) were identified.  Functional annotation revealed that branched-chain amino acid aminotransferase, glutamine synthetase, nitrate transporter, and glutamate decarboxylase might be important for amino acid metabolism.  Two significant loci, glutamine synthetase (Glu1, P=3.71×10^–4; Arg1, P=4.61×10^–5) and branched-chain amino acid aminotransferase (Val1, P=4.67×10^–5; I_Leu1, P=3.56×10^–6), were identified, respectively.  Based on the genotyping result, two alleles of CsGS (CsGS-L and CsGS-H) and CsBCAT (CsBCAT-L and CsBCAT-H) were selected to perform function verification.  Overexpression of CsGS-L and CsGS-H enhanced the contents of glutamate and arginine in transgenic plants, and overexpression of CsBCAT-L and CsBCAT-H promoted the accumulation of valine, isoleucine and leucine.  Enzyme activity assay uncovered that SNP₁₀₅₄ is important for CsGS catalyzing glutamate into glutamine.  Furthermore, CsGS-L and CsGS-H differentially regulated the accumulation of glutamine, and CsBCAT-L and CsBCAT-H differentially regulated the accumulation of branched-chain amino acids.  In summary, the findings in our study would provide new insights into the genetic basis of amino acids contents variation in tea plants and facilitate the identification of elite genes to enhance amino acids content.