Developing and excavating new agrochemicals with highly active and safe is an important tactic for protecting crop health and food safety.  In this paper, to discover the new bactericide candidates, we designed, prepared a new type of 1,2,3,4-tetrahydro-β-carboline (THC) derivatives and evaluated the in vitro and in vivo bioactivities against the Xanthomonas oryzae pv. oryzae (Xoo), Xanthomonas axonopodis pv. citri (Xac), and Pseudomonas syringae pv. actinidiae (Psa).  The in vitro bioassay results exhibited that most title molecules possessed good activity toward the three plant pathogenic bacteria, the compound A₁₇ showed the most active against Xoo and Xac with EC₅₀ values of 7.27 and 4.89 mg mL^–1 respectively, and compound A₈ exhibited the best inhibitory activity against Psa with EC₅₀ value of 4.87 mg mL^–1.  Pot experiments showed that compound A₁₇ exhibited excellent in vivo antibacterial activities to manage rice bacterial leaf blight and citrus bacterial canker, with protective efficiencies of 52.67 and 79.79% at 200 mg mL^–1, respectively.  Meanwhile, compound A₈ showed good control efficiency (84.31%) against kiwifruit bacterial canker at 200 mg mL^–1.  Antibacterial mechanism suggested that these compounds could interfere with the balance of the redox system, damage the cell membrane, and induce the apoptosis of Xoo cells.  Taken together, our study revealed that tetrahydro-β-carboline derivatives could be a promising candidate model for novel broad-spectrum bactericides.

The yellow seed trait is preferred by breeders for its potential to improve the seed quality and commercial value of Brassica napus.  In the present study, we produced yellow seed mutants using a CRISPR/Cas9 system when the two BnPAP2 homologs were knocked out.  Histochemical staining of the seed coat demonstrated that proanthocyanidin accumulation was significantly reduced in the pap2 double mutants and decreased specifically in the endothelial and palisade layer cells of the seed coat.  Transcriptomic and metabolite profiling analysis suggested that disruption of the BnPAP2 genes could reduce the expression of structural and regulated genes in the phenylpropanoid and flavonoid biosynthetic pathways.  The broad suppression of these genes might hinder proanthocyanidin accumulation during seed development, and thereby causing the yellow seed trait in B. napus.  These results indicate that BnPAP2 might play a vital role in the regulatory network controlling proanthocyanidin accumulation.

Excessive use of organophosphate pesticides (OP), such as dichlorvos, in farming system poses a threat to human health through potential contamination of environment.  To date, biodegradation has been prospected most promising approach to eliminate environmental OP residues.  Trichoderma species as a biological control microorganism is often exposed to the chemical pesticides applied in environments, so it is necessary to understand the mechanism of degradation of dichlorvos by Trichoderma.  In this study, dichlorvos significantly inhibited the growth, sporulation and pigmentation of T. atroviride T23, and the dichlorvos degradation activity of T23 required the initial induction effect of dichlorvos and the culture conditions, including the nutrient and pH values of the medium.  Various changed primary and secondary metabolites released from T23 in the presence of dichlorvos were speculated as the energy and antioxidants for the strain itself to tolerate dichlorvos stress.  The results showed that T23 could produce a series of enzymes, especially the intracellular enzymes, to degrade dichlorvos.  The activities of the intracellular enzyme generated by T23 were differentially changed along time course and especially relied on initial dichlorvos concentration, ammonium sulfate and phosphate added in the medium.  In conclusion, some dichlorvos-induced chemical degradation related enzymes of T23 were proved to be involved in the degradation of dichlorvos.

Plant architecture and leaf color are important factors influencing cotton fiber yield. In this study, based on genetic analysis, stem paraffin sectioning, and phytohormone treatments, we showed that the dwarf-red (DR) cotton mutant is a gibberellin-sensitive mutant caused by a mutation in a single dominant locus, designated GhDR. Using bulked segregant analysis (BSA) and genotyping by target sequencing (GBTS) approaches, we located the causative mutation to a ~197-kb genetic interval on chromosome A09 containing 25 annotated genes. Based on gene annotation and expression changes between the mutant and normal plants, GH_A09G2280 was considered to be the best candidate gene responsible for the dwarf and red mutant phenotypes. A 2-nucleotide deletion was found in the coding region of GhDR/GH_A09G2280 in the DR mutant, which caused a frameshift and truncation of GhDR. GhDR is a homolog of Arabidopsis AtBBX24, and encodes a B-box zinc finger protein. The frameshift deletion eliminated the C-terminal nuclear localization domain and the VP domain of GhDR, and altered its subcellular localization. A comparative transcriptome analysis demonstrated downregulation of the key genes involved in gibberellin biosynthesis and the signaling transduction network, as well as upregulation of the genes related to gibberellin degradation and the anthocyanin biosynthetic pathway in the DR mutant. The results of this study revealed the potential molecular basis by which plant architecture and anthocyanin accumulation are regulated in cotton.  

High-molecular-weight glutenin subunits (HMW-GSs) are the most critical grain storage proteins that determine the unique processing qualities of wheat. Although it is a part of the superior HMW-GS pair (Dx5+Dy10), the contribution of the Dy10 subunit to wheat processing quality remains unclear. In this study, we elucidated the effect of Dy10 on wheat processing quality by generating and analyzing a deletion mutant (with the Dy10-null allele), and by elucidating the changes to wheat flour following the incorporation of purified Dy10. The Dy10-null allele was transcribed normally, but the Dy10 subunit was lacking. These findings implied that the Dy10-null allele reduced the glutenin:gliadin ratio and negatively affected dough strength (i.e., Zeleny sedimentation value, gluten index, and dough development and stability times) and the bread-making quality; however, it positively affected the biscuit-making quality. The incorporation of various amounts of purified Dy10 into wheat flour had a detrimental effect on biscuit-making quality. The results of this study demonstrate that the Dy10 subunit is essential for maintaining wheat dough strength. Furthermore, the Dy10-null allele may be exploited by soft wheat breeding programs.

The brown planthopper (Nilaparvata lugens) is the main migratory pest in many rice growing areas in Asia.  E78 is a member of the nuclear hormone receptor superfamily which plays an important role in egg development and maternal regulation of early embryogenesis.  In this study, brown planthopper E78 (NlE78) was cloned, and the predicted amino acid sequence showed that it contains two conserved domains: NR-LBD and DBD.  qRT-PCR showed that the expression of NlE78 is high in the fifth instar nymphs and the ovaries of females.  After downregulation of NlE78, the rate of moulting failure (33.2%) increased significantly, and ovarian development was delayed.  However, when NlE78 was downregulated together with NlE93, the emergence rate increased significantly (78.79%), and ovarian development was similar to that when NlE78 was downregulated but not delayed.  A co-immunoprecipitation experiment showed that NlE78 interacts with NlE93, a crucial downstream transcription factor of the ecdysone signalling pathway.  Cellular localization by immunofluorescence revealed that NlE78 and NlE93 are expressed in the nucleus.  This study indicates that NlE78 regulates ovarian development and moulting, possibly through its interaction with NlE93.  This study is of great significance for the development of new pesticides and control methods based on newly discovered targets.

Soil salinity affects the expression of serine/arginine-rich (SR) genes and isoforms by alternative splicing, which in turn regulates the adaptation of plants to stress.  We previously identified the cassava spliceosomal component 35 like (SCL) and SR subfamilies, belonging to the SR protein family, which are extensively involved in responses to abiotic stresses.  However, the post-transcriptional regulatory mechanism of cassava arginine/serine-rich (RS) subfamily in response to salt stress remains to be explored.  In the current study, we identified 37 genes of the RS subfamily from 11 plant species and systematically investigated the transcript levels of the RS40 and RS31 genes under diverse abiotic stress conditions.  Subsequently, an analysis of the conserved protein domains revealed that plant RS subfamily genes were likely to preserve their conserved molecular functions and played critical functional roles in responses to abiotic stresses.  Importantly, we found that overexpression of MeRS40 in Arabidopsis enhanced salt tolerance by maintaining reactive oxygen species homeostasis and up-regulating the salt-responsive genes.  However, overexpression of MeRS40 gene in cassava reduced salt tolerance due to the depression of its endogenous gene expression by negative autoregulation of its own pre-mRNA.  Moreover, the MeRS40 protein interacted with MeU1-70Ks (MeU1-70Ka and MeU1-70Kb) in vivo and in vitro, respectively.  Therefore, our findings highlight the critical role of cassava SR proteins in responses to salt stress in plants. 

Cylas formicarius is one of the most important pests of sweet potato worldwide, causing considerable ecological and economic damage.  This study improved the effect of comprehensive management and understanding of genetic mechanisms by examining the functional genomics of C. formicarius.  Using Illumina and PacBio sequencing, this study obtained a chromosome-level genome assembly of adult weevils from lines inbred for 15 generations.  The high-quality assembly obtained was 338.84 Mb, with contig and scaffold N50 values of 14.97 and 34.23 Mb, respectively.  In total, 157.51 Mb of repeat sequences and 11 907 protein-coding genes were predicted.  A total of 337.06 Mb of genomic sequences was located on the 11 chromosomes, accounting for 99.03% of the total length of the associated chromosome.  Comparative genomic analysis showed that C. formicarius was sister to Dendroctonus ponderosae, and C. formicarius diverged from D. ponderosae approximately 138.89 million years ago (Mya).  Many important gene families expanded in the C. formicarius genome were involved in the detoxification of pesticides, tolerance to cold stress and chemosensory system.  To further study the role of odorant-binding proteins (OBPs) in olfactory recognition of C. formicarius, the binding assay results indicated that CforOBP4–6 had strong binding affinities for sex pheromones and other ligands.  The high-quality C. formicarius genome provides a valuable resource to reveal the molecular ecological basis, genetic mechanism, and evolutionary process of major agricultural pests; it also offers new ideas and new technologies for ecologically sustainable pest control.

Meloidogyne incognita is a devastating plant-parasitic nematode.  Effectors play important roles during the stages of nematodes infection and parasitism, but their molecular functions remain largely unknown.  In this study, we characterized a new effector, Minc03329, which contains signal peptide for secretion and a C-type lectin domain.  The yeast signal sequence trap experiments indicated that the signal peptide of Minc03329 is functional.  In situ hybridization showed that Minc03329 was specifically expressed in the subventral esophageal gland.  Real-time qPCR confirmed that the expression level of Minc03329 transcript was significantly increased in pre-parasitic and parasitic second-stage juveniles (pre-J2s and par-J2s).  Tobacco rattle virus (TRV)-mediated gene silencing of Minc03329 in host plants largely reduced the pathogenicity of nematodes.  On the contrary, ectopic expression of Minc03329 in Arabidopsis thaliana significantly increased plant susceptibility to nematodes.  Transient expression of Minc03329 in Nicotiana benthamiana leaves suppressed the programmed cell death triggered by the pro-apoptotic protein BAX.  Moreover, the transcriptome analysis of Minc03329-transgenic Arabidopsis and wild type revealed that many defense-related genes were significantly down-regulated.  Interestingly, some different expressed genes were involved in the formation of nematode feeding sites.  These results revealed that Minc03329 is an important effector for M. incognita, suppressing host defense response and promoting pathogenicity.

Reducing agricultural carbon emissions is important to enable carbon emission peaking by 2030 in China.  However, China’s transformation towards large-scale farming brings uncertainties to carbon emission reduction.  This study quantifies the carbon emissions from cropping based on life cycle assessment and estimates the effects of farm size on carbon emissions using a fixed effects model.  Furthermore, the variations of the carbon emissions from cropping driven by the changes in farm size in future years are projected through scenario analysis.  Results demonstrate an inverted U-shaped change in total carbon emission from cropping as farm size increases, which is dominated by the changes in the carbon emission from fertilizer.  Projections illustrate that large-scale farming transformation will postpone the peak year of total carbon emission from cropping until 2048 if the change in farm size follows a historical trend, although it is conducive to reducing total carbon emission in the long run.  The findings indicate that environmental regulations to reduce fertilizer usages should be strengthened for carbon emission abatement in the early stage of large-scale farming transformation, which are also informative to other developing countries with small farm size.

Potato is one of the staple food crops in North China.  However, potato production in this region is threatened by the low amount and high spatial-temporal variation of precipitation.  Increasing yield and water use efficiency (WUE) of potato by various water management practices under water resource limitation is of great importance for ensuring food security in China.  However, the contributions of different water management practices to yield and WUE of potato have been rarely investigated across North China’s potato planting region.  Based on meta-analysis of field experiments from the literature and model simulation, this study quantified the potential yields of potatoes without water and fertilizer limitation, and yield under irrigated and rainfed conditions, and the corresponding WUEs across four potato planting regions including the Da Hinggan Mountains (DH), the Foothills of Yanshan hilly (YH), the North foot of the Yinshan Mountains (YM), and the Loess Plateau (LP) in North China.  Simulated average potential potato tuber dry weight yield by the APSIM-Potato Model was 12.4 t ha^–1 for the YH region, 11.4 t ha^–1 for the YM region, 11.2 t ha^–1 for the DH region, and 10.7 t ha^–1 for the LP region, respectively.  Observed rainfed potato tuber dry weight yield accounted for 61, 30, 28 and 24% of the potential yield in the DH, YH, YM, and LP regions.  The maximum WUE of 2.2 kg m^–3 in the YH region, 2.1 kg m^–3 in the DH region, 1.9 kg m^–3 in the YM region and 1.9 kg m^–3 in the LP region was achieved under the potential yield level.  Ridge-furrow planting could boost yield by 8–49% and WUE by 2–36% while ridge-furrow planting with film mulching could boost yield by 35–89% and WUE by 7–57% across North China.  Our study demonstrates that there is a large potential to increase yield and WUE simultaneously by combining ridge-furrow planting with film mulching and supplemental irrigation in different potato planting regions with limited water resources.

Chromatin accessibility plays a vital role in gene transcriptional regulation.  However, the regulatory mechanism of chromatin accessibility, as well as its role in regulating crucial gene expression and kernel development in maize (Zea mays) are poorly understood.  In this study, we isolated a maize kernel mutant designated as defective kernel219 (dek219), which displays opaque endosperm and embryo abortion.  Dek219 encodes the DICER-LIKE1 (DCL1) protein, an essential enzyme in miRNA biogenesis.  Loss of function of Dek219 results in significant reductions in the expression levels of most miRNAs and histone genes.  Further research showed that the Heat shock transcription factor17 (Hsf17)-Zm00001d016571 module may be one of the factors affecting the expression of histone genes.  Assay results for transposase-accessible chromatin sequencing (ATAC-seq) indicated that the chromatin accessibility of dek219 is altered compared with that of wild type (WT), which may regulate the expression of crucial genes in kernel development.  By analyzing differentially expressed genes (DEGs) and differentially accessible chromatin regions (ACRs) between WT and dek219, we identified 119 candidate genes that are regulated by chromatin accessibility, including some reported to be crucial genes for kernel development.  Taken together, these results suggest that Dek219 affects chromatin accessibility and the expression of crucial genes that are required for maize kernel development

The trichomes of rice leaves are formed by the differentiation and development of epidermal cells.  Plant trichomes play an important role in stress resistance and protection against direct ultraviolet irradiation.  However, the development of rice trichomes remains poorly understood.  In this study, we conducted ethylmethane sulfonate (EMS)-mediated mutagenesis on the wild-type (WT) indica rice ‘Xida 1B’.  Phenotypic analysis led to the screening of a mutant that is defective in trichome development, designated lhl1 (less hairy leaf 1).  We performed map-based cloning and localized the mutated gene to the 70-kb interval between the molecular markers V-9 and V-10 on chromosome 2.  The locus LOC_Os02g25230 was identified as the candidate gene by sequencing.  We constructed RNA interference (LHL1-RNAi) and overexpression lines (LHL1-OE) to verity the candidate gene.  The leaves of the LHL1-RNAi lines showed the same trichome developmental defects as the lhl1 mutant, whereas the trichome morphology on the leaf surface of the LHL1-OE lines was similar to that of the WT, although the number of trichomes was significantly higher.  Quantitative real-time PCR (RT-qPCR) analysis revealed that the expression levels of auxin-related genes and positive regulators of trichome development in the lhl1 mutant were down-regulated compared with the WT.  Hormone response analysis revealed that LHL1 expression was affected by auxin.  The results indicate that the influence of LHL1 on trichome development in rice leaves may be associated with an auxin pathway.

This study investigated cold plasmas for multiple biological applications.  Our previous work has found dielectric barrier discharge plasma improves chicken sperm quality.  The number of Sertoli cells (SCs) decides spermatogenesis.  However, whether cold plasma can regulate SC proliferation remains unclear.  This study explored the effects of cold plasma on immature chicken SC proliferation and the regulation mechanism.  Results showed that cold plasma exposure at 2.4 W for 30 s twice with an interval of 6 h produced (P<0.05) the maximum SC viability, cell growth, and cell cycle progression.  SC proliferation-promoting effect of cold plasma treatment was regulated by increasing (P<0.05) the adenosine triphosphate production and the respiratory enzyme activity in the mitochondria.  This process was potentially mediated by the adenosine monophosphate-activated protein kinase (AMPK)–mammalian target of rapamycin (mTOR) signaling pathway, which was regulated by the microRNA (miRNA) targeting regulation directly and by the intracellular reactive oxygen species homeostasis indirectly.  The cold plasma treatment increased (P<0.01) the miR-7450-5p expression and led to a decreased (P<0.01) AMPKα1 level.  On the other hand, miR-100-5p expression was reduced (P<0.05) and led to an increased (P<0.05) mTOR level in SCs.  A single-stranded synthetic miR-7450-5p antagomir and a double-stranded synthetic miR-100-5p agomir reduced (P<0.05) the SC proliferation.  However, this could be ameliorated (P<0.05) by the cold plasma treatment.  Our findings suggest that appropriate cold plasma treatment provides a safe strategy to improve SC proliferation, which is beneficial to elevating male chicken reproductive capacity.

Some H5 viruses isolated in poultry or wild birds between 2020 and 2021 were found to be antigenically different from the vaccine strains (H5-Re11 and H5-Re12) used in China.  In this study, we generated three new recombinant vaccine seed viruses by using reverse genetics and used them for vaccine production.  The vaccine strain H5-Re13 contains the hemagglutinin (HA) and neuraminidase (NA) genes of an H5N6 virus that bears the clade 2.3.4.4h HA gene, H5-Re14 contains the HA and NA genes of an H5N8 virus that bears the clade 2.3.4.4b HA gene, and H7-Re4 contains the HA and NA genes of H7N9 virus detected in 2021.  We evaluated the protective efficacy of the novel H5/H7 trivalent inactivated vaccine in chickens, ducks, and geese.  The inactivated vaccine was immunogenic and induced substantial antibody responses in the birds tested.  Three weeks after vaccination, chickens were challenged with five different viruses detected in 2020 and 2021: three viruses (an H5N1 virus, an H5N6 virus, and an H5N8 virus) bearing the clade 2.3.4.4b HA gene, an H5N6 virus bearing the clade 2.3.4.4h HA gene, and an H7N9 virus.  All of the control birds shed high titers of virus and died within 4 days post-challenge, whereas the vaccinated chickens were completely protected from these viruses.  Similar protective efficacy against H5 viruses bearing the clade 2.3.4.4h or 2.3.4.4b HA gene was observed in ducks and geese.  Our study indicates that the newly updated H5/H7 vaccine can provide solid protection against the H5 and H7N9 viruses that are currently circulating in nature.  

Myo-inositol and its derivatives play important roles in the tolerance of higher plants to abiotic stresses, and myo-inositol-1-phosphate synthase (MIPS) is the rate-limiting enzyme in myo-inositol biosynthesis.  In this study, we found that increased myo-inositol biosynthesis enhanced drought tolerance in MdMIPS1-overexpressing apple lines under short-term progressive drought stress.  The effect of myo-inositol appeared to be mediated by the increased accumulation of osmoprotectants such as glucose, sucrose, and proline, and by the increased activities of antioxidant enzymes that eliminate reactive oxygen species.  Moreover, enhanced water-use efficiency (WUE) was observed in MdMIPS1-overexpressing apple lines under long-term moderate water deficit conditions that mimicked the water availability in the soil of the Loess Plateau.  Enhanced WUE may have been associated with the synergistic regulation of osmotic balance and stomatal aperture mediated by increased myo-inositol biosynthesis.  Taken together, our findings shed light on the positive effects of MdMIPS1-mediated myo-inositol biosynthesis on drought tolerance and WUE in apple.

To address the relationships between the amount of nitrogen fertilizer application and the yield of double cropping rice systems, we investigated the effects of a cultivation pattern of strong seedlings with increased planting density and reduced nitrogen application (SDN) on the morphological and physiological characteristics of double cropping rice.  Our results indicated that the effects of SDN on the morphological characteristics of the single plant roots of double cropping rice were not significant, but the morphological characteristics of the population roots were largely different.  Specifically, SDN significantly increased the morphological indexes of the root population such as root fresh weight, root volume, root number, root length and root dry weight.  The effects of SDN on the total root absorption areas and root active absorption areas of the single plants were non-significant, but it dramatically enhanced the total root absorption areas and root active absorption areas of the plant population during the tillering, heading and mature stages.  In addition, SDN significantly increased the root bleeding intensity and elevated the soluble sugar and free amino acid contents of root bleeding sap.  Compared to the traditional cultivation pattern (CK), SDN significantly increased root bleeding intensity at the heading stage by 4.37 and 8.90% for early and late rice, respectively.  Meanwhile, SDN profoundly enhanced the soluble sugar contents of root bleeding sap by 12.85 and 10.41% for early and late rice, respectively.  In addition, SDN also significantly enhanced free amino acid content of root bleeding sap by 43.25% for early rice and by 37.50% for late rice systems compared to CK.  Furthermore, SDN increased the actual yield of double cropping rice mainly due to the higher effective panicle number and the larger seed-setting rate.  The actual yields of early rice under SDN were higher than CK by 9.37 and 5.98% in 2016 and 2017, and the actual yields of late rice under SDN were higher than CK by 0.20 and 1.41% in 2016 and 2017, respectively.  Correlation analysis indicated that the significant positive correlations were observed between the majority of the root indexes and the actual yield across the four different growth stages.

Domestication and genetic improvement of maize improve yield and stress tolerance due to changes in morphological and physiological properties, which likely alter rhizosphere microbial diversity.  Understanding how the evolution of maize germplasm impacts its rhizobacterial traits during the growth stage is important for optimizing plant-microbe associations and obtaining yield gain in domesticated germplasms.  In this study, a total of nine accessions representing domestication and subsequent genetic improvement were selected.  We then sequenced the plant DNA and rhizobacterial DNA of teosinte, landraces and inbred lines at the seedling, flowering and maturity stages in a field trial.  Moreover, the soil chemical properties were determined at the respective stages to explore the associations of soil characteristics with bacterial community structures.  The results showed that domestication and genetic improvement increased the rhizobacterial diversity and substantially altered the rhizobacterial community composition.  The core microbiome in the rhizosphere differed among germplasm groups.  The co-occurrence network analysis demonstrated that the modularity in the bacterial network of the inbred lines was greater than those of teosinte and the landraces.  In conclusion, the increased diversity of the rhizobacterial community with domestication and genetic improvement may improve maize resilience to biotic stresses and soil nutrient availability to plants. 

Plant height is an important agronomic trait, which is governed by multiple genes with major or minor effects.  Of numerous QTLs for plant height reported in soybean, most are in large genomic regions, which results in a still unknown molecular mechanism for plant height.  Increasing the density of molecular markers in genetic maps will significantly improve the efficiency and accuracy of QTL mapping.  This study constructed a high-density genetic map using 4 011 recombination bin markers developed from whole genome re-sequencing of 241 recombinant inbred lines (RILs) and their bi-parents, Zhonghuang 13 (ZH) and Zhongpin 03-5373 (ZP).  The total genetic distance of this bin map was 3 139.15 cM, with an average interval of 0.78 cM between adjacent bin markers.  Comparative genomic analysis indicated that this genetic map showed a high collinearity with the soybean reference genome.  Based on this bin map, nine QTLs for plant height were detected across six environments, including three novel loci (qPH-b_11, qPH-b_17 and qPH-b_18).  Of them, two environmentally stable QTLs qPH-b_13 and qPH-b_19-1 played a major role in plant height, which explained 10.56–32.7% of the phenotypic variance.  They were fine-mapped to 440.12 and 237.06 kb region, covering 54 and 28 annotated genes, respectively.  Via the function of homologous genes in Arabidopsis and expression analysis, two genes of them were preferentially predicted as candidate genes for further study.

Strong seedlings are essential for high yield.  To explore the foundation of strong seedlings, we investigated various factors influencing the conversion and distribution of seed storage reserves during seedling establishment in maize inbred lines.  Three maize inbred lines were used to explore the effects of seed size, seed vigor, illumination duration, temperature, water content, and salt concentration of the seedling medium on the utilization of seed storage reserves during seedling establishment.  The results showed that the conversion rate of small seeds was 3.69 to 17.71% higher than that of large seeds.  Moreover, prolonged illumination time was conducive to the formation of strong seedlings.  However, low temperature, drought stress and salt stress reduced the conversion rate of seed storage reserves and increased the root/shoot ratio.  These results could be used to guide field management during seedling emergence and develop improved germplasm with a high conversion rate of seed storage reserves.

An improved straw mulching model may be a sustainable agricultural production technology due to its improvements in soil water and the fertilizer environment by the recycling of waste straw resources.  A four-year field experiment was conducted in a randomized block design on the Loess Plateau of northwestern China in 2015–2019, which aimed to study the effects of straw strip mulching (SSM) and conventional flat planting without mulching (CK) on soil water storage, water consumption characteristics, water use efficiency, precipitation use efficiency, winter wheat growth, economic benefits, and nutrient benefits.  The results obtained for the four years showed that the SSM treatment improved soil water storage in the 0–180 cm soil layer over the whole growth period, which was especially obvious in the 0–60 cm soil layer at the jointing and blooming stages.  Compared with CK, SSM increased the contribution rate of precipitation to total evapotranspiration and increased it quite significantly by 20.4 percentage points in the earlier growth period.  SSM significantly reduced soil water storage consumption in the 0–180 cm soil layer and ultimately reduced evapotranspiration by 11.2 mm during the whole period.  In the 0–180 cm soil layer, SSM decreased evapotranspiration by 33.1 mm from the sowing to the jointing stages, but increased it by 19.5 mm from the jointing to the blooming stages.  In addition, SSM improved the water use efficiency of grain yield by 21.6% and improved the precipitation use efficiency of grain yield by 18.6%, and it ultimately increased grain yield by 16.5% through improving spike number by 9.5% and kernel number per spike by 8.9%.  SSM improved the water use efficiency of biomass yield by 13.5% and the precipitation use efficiency of biomass yield by 9.9%, and it ultimately increased biomass yield by 8.7% and plant height by 6.5%.  Furthermore, SSM increased net income by 413 CNY ha^–1 and the total amount of straw returned to the field after harvest by 8 876–9 619 kg ha^–1.  After returning straw to the field, SSM significantly increased the soil nutrient contents, which could significantly reduce the burden of fertilization by farmers after a few years.  Therefore, straw strip mulching technology could probably be a sustainable and potentially useful practice, which could save water and increase efficiency in rainfed winter wheat production.

Understanding the genetic basis of quality-related traits contributes to the improvement of grain protein concentration (GPC), grain starch concentration (GSC), and wet gluten concentration (WGC) in wheat, a genome-wide association study (GWAS) based on a mixed linear model (MLM) was performed on the 236 wheat accessions including 160 cultivars and 76 landraces using 55K single nucleotide polymorphism (SNP) array in multiple environments. A total of twelve stable QTL/SNPs were identified to control different quality traits in this populations at least two environments under stripe rust stress; three, seven and two QTLs associated with GPC, GSC, and WGC were characterized respectively and located on chromosomes 1B, 1D, 2A, 2B, 2D, 3B, 3D, 5D, and 7D with the range of phenotypic variation explained (PVE) from 4.2 to 10.7%. Compared with the previously reported QTLs/genes, five QTLs (QGsc.sicau-1BL, QGsc.sicau-1DS, QGsc.sicau-2DL.1, QGsc.sicau-2DL.2, QWgc.sicau-5DL) were potentially novel. KASP markers for SNPs AX-108770574 and AX-108791420 on chromosome on 5D associated with wet gluten concentration were successfully developed. Phenotype of the cultivars containing the A-allele in AX-108770574 and T-allele in AX-108791420 were extremely significantly (P<0.01) higher than that of the landraces containing the G-allele or C-allele of wet gluten concentration in each of the environments. The developed and validated KASP markers could be utilized in molecular breeding aiming to improve the quality in wheat.

Salinity threatens soybean germination, growth and production.  The germination stage is a key period in the life of soybean.  Wild soybean contains many genes related to stress resistance that are valuable resources for the genetic improvement of soybean.  To identify the genetic loci of wild soybean that are active during seed germination under salt stress, two populations, a soybean interspecific hybrid population comprising 142 lines and a natural population comprising 121 wild soybean accessions, were screened for three germination-related traits in this study.  By using single-nucleotide polymorphism (SNP) markers with three salt tolerance indices, 25 quantitative trait loci (QTLs), 21 significant SNPs (–log₁₀(P)≥4.0) and 24 potential SNPs (3.5<–log₁₀(P)<4.0) were detected by linkage mapping and a genome-wide association study (GWAS) in two environments.  The key genetic region was identified based on these SNPs and QTLs.  According to the gene functional annotations of the W05 genome and salt-induced gene expression qRT-PCR analysis, GsAKR1 was selected as a candidate gene that responded to salt stress at the germination stage in the wild soybean.  These results could contribute to determining the genetic networks of salt tolerance in wild soybean and will be helpful for molecular marker-assisted selection in the breeding of salt-tolerant soybean.

The fresh postharvest golden needle mushroom (Flammulina velutipes) sporocarp has a high moisture content and crisp texture, but it still has high physiological activity and respiration, leading to senescence and quality deterioration.  Treatments with 1-methylcyclopropene (1-MCP) and polypropylene (PP) crispers were used to study the changes of lignification and softening of F. velutipes during storage.  The main findings were as follows: the crisper packaging could effectively prolong the storage time of F. velutipes; either the 1-MCP treatment, crisper packaging or the combination of the two treatments could significantly inhibit the accumulation of lignin and the decreases in the contents of cellulose and pectin, and had certain inhibitory effects on the activities of enzymes involved in lignification and softening including phenylalanine ammonia-lyase (PAL), cinnamyl alcohol dehydrogenase (CAD), cellulase (Cx), pectin methylesterase (PME) and polygalacturonase (PG).  Among them, the inhibitory effect of the crisper packaging was higher than the 1-MCP treatment, while the combination of the two treatments was the best.  The results of transmission electron microscopy (TEM) and scanning electron microscopy (SEM) showed that the crisper packaging in combination with the 1-MCP treatment could effectively maintain the integrity and stability of the F. velutipes cellular structure and inhibit the emergence of plasmolysis to prevent cell membrane rupture.  The transcription levels showed that the crisper packaging and the combination of the 1-MCP treatment and crisper packing could effectively affect the expression of genes for enzymes related to lignification and softening of F. velutipes.  In conclusion, 1-MCP and PP crispers could delay the lignification and softening of F. velutipes during storage.

Genetic linkage maps are important for quantitative trait locus (QTL) and marker-assisted selection breeding.  The wolfberry (Lycium spp.) is an important food and traditional medicine in China.  However, few construction genetic linkage maps have been reported because of the lack of genomic and genetic resources.  In this study, a population of 89 F₁ seedings was derived from a cross between two heterozygous parents, L. chinense var. potaninii ‘BF-01’ (female) and L. barbarum var. auranticarpum ‘NH-01’ (male), in order to construct a genetic linkage map using simple sequence repeat (SSR) and amplified fragment length polymorphism (AFLP) markers based on the double pseudo-test cross mapping strategy.  The resulting genetic map consisted of 165 markers (74 AFLPs and 91 SSRs) distributed across 12 linkage groups and spanned a total length of 557.6 cM with an average distance of 3.38 cM between adjacent markers.  The 12 linkage groups contained 3 to 21 markers and ranged in length from 8.6 to 58.3 cM.  Twenty-nine segregated markers distributed in the map were mainly located on LG4 and LG9 linkage groups at P<0.05.  This is the first linkage map of Lycium species using SSR and AFLP markers, which can serve as basis for improving genes and selective breeding of the genome assembly.

Elevated activities of cytosolic fructose-1,6-bisphosphatase (cyFBPase) and sedoheptulose-1,7-bisphosphatase (SBPase) are associated with higher yields in plants.  In this study, the expression levels of the cyFBPase and SBPase genes were increased by overexpressing rape (Brassica napus) cDNA in tobacco (Nicotiana tabacum) plants.  The transgenic plants co-expressing cyFBPase and SBPase (TpFS), or expressing single cyFBPase (TpF) or SBPase (TpS) had 1.77-, 1.55-, 1.23-fold cyFBPase and 1.45-, 1.12-, 1.36-fold SBPase activities as compared to the wild-type (WT), respectively.  Photosynthesis rates of TpF, TpS and TpFS increased 4, 20 and 25% compared with WT plants.  The SBPase and cyFBPase positively regulated each other and functioned synergistically in transgenic tobacco plants.  In addition, the sucrose contents of the three transgenic plants were higher than that of WT plants.  The starch accumulation of the TpFS and TpS plants was improved by 53 and 37%, but slightly decreased in TpF plants.  Moreover, the transgenic tobacco plants harbouring SBPase and/or cyFBPase genes showed improvements in their growth, biomass, dry weight, plant height, stem diameter, leaf size, flower number, and pod weight.  In conclusion, co-expression of SBPase and cyFBPase may pave a new way for improving crop yield in agricultural applications.

Effects of the heavy metal copper (Cu), the metalloid arsenic (As), and the antibiotic oxytetracycline (OTC) on bacterial community structure and diversity during cow and pig manure composting were investigated.  Eight treatments were applied, four to each manure type, namely cow manure with: (1) no additives (control), (2) addition of heavy metal and metalloid, (3) addition of OTC and (4) addition of OTC with heavy metal and metalloid; and pig manure with: (5) no additives (control), (6) addition of heavy metal and metalloid, (7) addition of OTC and (8) addition of OTC with heavy metal and metalloid.  After 35 days of composting, according to the alpha diversity indices, the combination treatment (OTC with heavy metal and metalloid) in pig manure was less harmful to microbial diversity than the control or heavy metal and metalloid treatments.  In cow manure, the treatment with heavy metal and metalloid was the most harmful to the microbial community, followed by the combination and OTC treatments.  The OTC and combination treatments had negative effects on the relative abundance of microbes in cow manure composts.  The dominant phyla in both manure composts included Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria.  The microbial diversity relative abundance transformation was dependent on the composting time.  Redundancy analysis (RDA) revealed that environmental parameters had the most influence on the bacterial communities.  In conclusion, the composting process is the most sustainable technology for reducing heavy metal and metalloid impacts and antibiotic contamination in cow and pig manure.  The physicochemical property variations in the manures had a significant effect on the microbial community during the composting process.  This study provides an improved understanding of bacterial community composition and its changes during the composting process.