Genetic improvement has promoted wheat’s grain yield and nitrogen use efficiency (NUE) during the past decades. Therefore, the current wheat cultivars exhibit higher grain yield and NUE than previous cultivars in the Yangtze River Basin, China since the 2000s. However, the critical traits and mechanisms of the increased grain yield and NUE remain unknown. This study explores the mechanisms underlying these new cultivars’ increased grain yield and NUE by studying 21 local cultivars cultivated for three growing seasons from 2016 to 2019. Significantly positive correlations were observed between grain yield and NUE in the three years. The cultivars were grouped into high (HH), medium (MM), and low (LL) grain yield and NUE groups. The HH group exhibited significantly high grain yield and NUE. High grain yield was attributed to more effective ears by high tiller fertility and greater single-spike yield by increasing postanthesis single-stem biomass. Compared to other groups, the HH group demonstrated a longer leaf stay-green ability and a greater flag leaf photosynthetic rate after anthesis. It also showed higher N accumulation at pre-anthesis, which contributed to increasing N accumulation per stem, including stem and leaf sheath, leaf blade, and unit leaf area at preanthesis, and promoting N uptake efficiency, the main contribution of high NUE. Moreover, tiller fertility was positively related to N accumulation per stem, N accumulation per unit leaf area, leaf stay-green ability, and flag leaf photosynthetic rate, which indicates that improving tiller fertility promoted N uptake, leaf N accumulation, and photosynthetic ability, thereby achieving synchronous improvements in grain yield and NUE. Therefore, tiller fertility is proposed as an important kernel indicator that can be used in the breeding and management of cultivars to improve agricultural efficiency and sustainability.

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.  

Large-scale crop mapping using remote sensing data is of great significance for agricultural production, food security and the sustainable development of human societies. Winter rapeseed is an important oil crop in China that is mainly distributed in the Yangtze River Valley. Traditional winter rapeseed mapping practices are insufficient since they only use the spectral characteristics during the critical phenological period of winter rapeseed, which are usually limited to a small region and cannot meet the needs of large-scale applications. In this study, a novel phenology-based winter rapeseed index (PWRI) was proposed to map winter rapeseed in the Yangtze River Valley. PWRI expands the date window for distinguishing winter rapeseed and winter wheat, and it has good separability throughout the flowering period of winter rapeseed. PWRI also improves the separability of winter rapeseed and winter wheat, which traditionally have been two easily confused winter crops. A PWRI-based method was applied to the Middle Reaches of the Yangtze River Valley to map winter rapeseed on the Google Earth Engine platform. Time series composited Sentinel-2 data were used to map winter rapeseed with 10 m resolution. The mapping achieved a good result with overall accuracy and kappa coefficients exceeding 92% and 0.85, respectively. The PWRI-based method provides a new solution for high spatial resolution winter rapeseed mapping at a large scale.

The fungal pathogen Setosphaeria turcica causes northern corn leaf blight (NCLB), which leads to considerable crop losses.  Setosphaeria turcica elaborates a specialized infection structures called appressorium for maize infection.  Previously, we demonstrated that the S. turcica triggers an S-phase checkpoint and ATR (Ataxia Telangiectasia and Rad3 related)-dependent self-protective response to DNA genotoxic insults during maize infection.  However, how the regulatory mechanism works was still largely unknown.  Here, we report a genome wide transcriptional profile analysis during appressorium formation in the present of DNA replication stress.  We performed RNA-Seq analysis to identify S. tuicica genes responsive to DNA replication stress.  In the current work, we found that appressorium-mediated maize infection by S. turcica is significantly blocked by S-phase checkpoint.  A large serial of secondary metabolite and melanin biosynthesis genes were blocked in appressorium formation of S. turcica during the replication stress.  The secondary metabolite biosynthesis genes including alcohol dehydrogenase GroES-like domain, multicopper oxidase, ABC-transporter families, cytochrome P450 and FAD-containing monooxygenase were related to plant pathogen infection.  In addition, we demonstrated that autophagy in S. turcica is up-regulated by ATR as a defense response to stress.  We identified StATG3, StATG4, StATG5, StATG7 and StATG16 genes for autophagy were induced by ATR-mediated S-phase checkpoint.  We therefore propose that in response to genotoxic stress, S. turcica utilizes ATR-dependent pathway to turn off transcription of genes governing appressorium-mediated infection, and meanwhile inducing transcription of autophagy genes likely as a mechanism of self-protection, aside from the more conservative responses in eukaryotes.

Fusarium graminearum is an important plant pathogenic fungus that causes disease and yield reduction in many cereal crops, such as wheat and barley.  Gyp8 stimulates GTP hydrolysis on Ypt1 in yeast.  However, the functions of Gyp8 in plant pathogenic fungi are still unknown.  In this study, we investigated the roles of FgGyp8 in F. graminearum by genetic and pathological analyses.  Through gene knockout and phenotypic analyses, we found that FgGyp8 is required for vegetative growth in F. graminearum.  The conidiation, conidial size and number of septa per conidium of ΔFggyp8 mutant are significantly reduced when compared to the wild type PH-1.  Furthermore, FgGyp8 is crucial for pathogenicity on wheat coleoptiles and wheat heads.  FgGyp8 contains a conserved TBC domain.  Domain deletion analysis showed that the TBC domain, C- and N-terminal regions of FgGyp8 are all important for its biological functions in F. graminearum.  Moreover, we showed that FgGyp8 catalyzes the hydrolysis of the GTP on FgRab1 to GDP in vitro, indicating that FgGyp8 is a GTPase-activating protein (GAP) for FgRab1.  In addition, we demonstrated that FgGyp8 is required for FgSnc1-mediated fusion of secretory vesicles with the plasma membrane in F. graminearum.  Finally, we showed that FgGyp8 has functional redundancy with another FgRab1 GAP, FgGyp1, in F. graminearum.  Taken together, we conclude that FgGyp8 is required for vegetative growth, conidiogenesis, pathogenicity and acts as a GAP for FgRab1 in F. graminearum.

A number of plant pathogenic species of Phytophthora are known to produce different classes of secretory proteins during interactions with their hosts.  Although several small cysteine-rich (SCR) secretory proteins, conserved in oomycete pathogens, have been identified in Phytophthora, their specific involvement in these interactions remains unknown.  In this study, an SCR effector encoded by Pnscr82 in P. nicotianae was identified and shown to have similarities to P. cactorum phytotoxic protein, PcF (Phytophthora cactorum Fragaria).  Agroinfection with potato virus X vector, PnSCR82, was capable of inducing plant hypersensitive cell death in Nicotiana benthamiana and Solanum lycopersicum.  Real-time PCR results indicated that transiently expressed PnSCR82 in N. benthamiana leaves activated the jasmonate, salicylic acid and ethylene signaling pathways.  Transient expression of PnSCR82 enhanced plant resisitance to P. capsici.  In summary, our results demonstrated that P. nicotianae PnSCR82 elicits defensive responses in N. benthamiana and may potentially play a significant role in future crop protection programs.

Accurate and timely classification of diseases during strawberry planting can help growers deal with them in timely manner, thereby reducing losses.  However, the classification of strawberry diseases in real planting environments is facing severe challenges, including complex planting environments, multiple disease categories with small differences, and so on.  Although recent mobile vision technology based deep learning has achieved some success in overcoming the above problems, a key problem is how to construct a non-destructive, fast and convenient method to improve the efficiency of strawberry disease identification for the multi-region, multi-space and multi-time classification requirements.  We develop and evaluate a rapid, low-cost system for classifying diseases in strawberry cultivation.  This involves designing an easy-to-use cloud-based strawberry disease identification system, combined with our novel self-supervised multi-network fusion classification model, which consists of a Location network, a Feedback network and a Classification network to identify the categories of common strawberry diseases.  With the help of a novel self-supervision mechanism, the model can effectively identify diseased regions of strawberry disease images without the need for annotations such as bounding boxes.  Using accuracy, precision, recall and F₁ to evaluate the classification effect, the results of the test set are 92.48, 90.68, 86.32 and 88.45%, respectively.  Compared with popular Convolutional Neural Networks (CNN) and five other methods, our network achieves better disease classification effect.  Currently, the client (mini program) has been released on the WeChat platform.  The mini program has perfect classification effect in the actual test, which verifies the feasibility and effectiveness of the system, and can provide a reference for the intelligent research and application of strawberry disease identification.

In 2009, an emerging citrus viral disease caused by Citrus chlorotic dwarf-associated virus (CCDaV) was discovered in Yunnan Province of China.  However, the occurrence and spread of CCDaV in other citrus-growing provinces in China is unknown to date.  To better understand the distribution and molecular diversity of CCDaV in China, a total of 1 772 citrus samples were collected from 11 major citrus-growing provinces and were tested for CCDaV by PCR.  Among these, 134 citrus samples from Guangxi, Yunnan and Guangdong were tested positive for CCDaV, demonstrating that the occurrence and spread of CCDaV are increasing in China.  The complete genome sequences of 17 CCDaV isolates from different provinces and hosts were sequenced.  Comparisons of the whole-genome sequences of the 17 CCDaV isolates as well as the 15 isolates available in GenBank revealed that the sequence identity was about 99–100%, showing that the CCDaV isolates were highly conserved.  Phylogenetic studies showed that the 32 CCDaV isolates belonged to four different groups based on geographical origins and host species, and that CCDaV isolates from China and Turkey were clustered into different groups.  The results provide important information for clarifying the distribution and genetic diversity of CCDaV in China.

This experiment was conducted to evaluate the effects of Bupleurum extract (BE) on blood metabolites, antioxidant status, and immune function in dairy cows under heat stress.  Forty lactating Holstein cows were randomly assigned to 1 of 4 treatments.  The treatments consisted of 0, 0.25, 0.5, and 1.0 g of BE kg^–1 dry matter.  Supplementation with BE decreased (P<0.05) blood urea nitrogen (BUN) contents and increased blood total protein (TP) and albumin (ALB) levels compared with control cows, but it had no effects (P>0.05) on blood glucose (GLU), nonesterified fatty acid (NEFA), total triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and high density lipoprotein cholesterol (HDL-C).  Compared with control cows, cows fed BE had higher (P<0.05) superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activity.  However, supplementation with BE had no effect (P>0.05) on total antioxidant capacity (T-AOC) or malondialdehyde (MDA) levels.  The immunoglobulin (Ig) A and G contents increased (P<0.05) in cows fed 0.25 or 0.5 g of BE kg^–1.  Interleukin (IL)-2 and IL-4 levels were higher (P<0.05) in cows fed 0.5 and 1.0 g of BE kg^–1, and IL-6 was significantly elevated (P<0.05) in cows fed 0.5 g of BE kg^–1.  There were no treatment effects (P>0.05) on the CD4⁺ and CD8⁺ T lymphocyte ratios, CD4⁺/CD8⁺ ratio, or tumor necrosis factor-α (TNF-α) level among the groups.  These findings suggest that BE supplementation may improve protein metabolism, in addition to enhancing antioxidant activity and immune function in heat-stressed dairy cows.  

To separate the proteins related to pigment synthesis in green colored fiber (GCF), we performed a comparative proteomic analysis to identify the differentially expressed proteins between green cotton fiber and a white near-isogenic line (NIL).  One differential spot identified as phenylocumaran benzylic ether redutase-like protein (PCBER) was expressed only in GCF, but was not found in white colored fiber (WCF) at any time points.  Since PCBER was a key enzyme in lignans biosynthesis, total lignans were extracted from GCF and WCF and their content was determined by using a chromotropic acid spectrophotometric method.  The results showed that total lignans content in GCF was significantly higher than that in WCF.  The qPCR analysis for two PLR genes associated with lignans biosynthesis showed that the expression level of two genes was much higher in GCF than that in WCF at 24 and 27 days post anthesis (DPA), which may be responsible for the higher lignans content in GCF.  Our study suggested that PCBER and lignans may be responsible for the color difference between GCF and WCF.  Additionally, p-dimethylaminocinnamaldehyde (DMACA) staining demonstrated that the pigment in GCF was not proanthocyanidins, and was different from that in brown colored fiber (BCF).  This study provided new clues for uncovering the molecular mechanisms related to pigment biosynthesis in GCF.

   Flowering time and branching type are important agronomic traits related to the adaptability and yield of soybean. Molecular bases for major flowering time or maturity loci, E1 to E4, have been identified. However, more flowering time genes in cultivars with different genetic backgrounds are needed to be mapped and cloned for a better understanding of flowering time regulation in soybean. In this study, we developed a population of Japanese cultivar (Toyomusume)×Chinese cultivar (Suinong 10) to map novel quantitative trait locus (QTL) for flowering time and branch number. A genetic linkage map of a F₂ population was constructed using 1 306 polymorphic single nucleotide polymorphism (SNP) markers using Illumina SoySNP8k iSelect BeadChip containing 7 189 (SNPs). Two major QTLs at E1 and E9, and two minor QTLs at a novel locus, qFT2_1 and at E3 region were mapped. Using other sets of F₂ populations and their derived progenies, the existence of a novel QTL of qFT2_1 was verified. qBR6_1, the major QTL for branch number was mapped to the proximate to the E1 gene, inferring that E1 gene or neighboring genetic factor is significantly contributing to the branch number.

Plant cell walls constitute the skeletal structures of plant bodies, and thus confer lodging resistance for grain crops.  While the basic cell wall synthesis machinery is relatively well established now, our understanding of how the process is regulated remains limited and fragmented.  In this study, we report the identification and characterization of the novel rice (Oryza sativa L.) brittle culm16 (brittle node; bc16) mutant.  The brittle node phenotype of the bc16 mutant appears exclusively at nodes, and resembles the previously reported bc5 mutant.  Combined histochemical staining and electron microscopy assays revealed that in the bc16 mutant, the secondary cell wall formation and thickening of node sclerenchyma tissues are seriously affected after heading.  Furthermore, cell wall composition assays revealed that the bc16 mutation led to a significant reduction in cellulose and lignin contents.  Using a map-based cloning approach, the bc16 locus is mapped to an approximately 1.7-Mb region of chromosome 4.  Together, our findings strengthen evidence for discretely spatial differences in the secondary cell wall formation within plant bodies.

The tetracycline (Tet)-off gene expression regulation system based on the TetR-VP16/Top10 construct has not been widely utilized in plants, for its highly expressed TetR-VP16 activator is toxic to some plants and repeatedly replenishing tetracycline to turn off the constitutively active system is a tedious process.  To solve these problems, a Tet-off and heat shock (HS)-on gene expression regulation system was constructed in this study.  This system is composed of a chimeric transactivator gene TetR-HSF that is derived from a Tet repressor (TetR) and a HS transcription factor (HSF) controlled by a HS promoter HSP70m, and a Tet operator containing hybrid promoter, Om35S, that drives expression of the β-glucuronidase (GUS) gene.  The resultant system yields a GUS expression pattern similar to that of the HSP70m promoter under inducing temperatures and at 35 and 40°C drives GUS expression to a similar level as the Cauliflower mosaic virus (CaMV) 35S promoter.  Further examination revealed that the TetR-HSF and GUS genes were induced by HS, reaching peak expression after 1 and 6 h treatment, respectively, and the HS induction of the expression system could be inhibited by Tet.  This system will provide a useful tool for transgenic studies of plants in the laboratory and in the field, including transgene function analysis, agronomic trait improvement, biopharmaceutical protein production and others.

Leaves are the main organs of photosynthesis in green plants.  Leaf area plays a vital role in dry matter accumulation and grain yield in maize (Zea mays L.).  Thus, investigating the genetic basis of leaf area will aid efforts to breed maize with high yield.  In this study, a total of 150 F₇ recombinant inbred lines (RILs) derived from a cross between the maize lines Xu 178 and K12 were used to evaluate three ear-leaves area (TELA) under multi-environments.  Inclusive composite interval mapping (ICIM) was used to identify quantitative trait loci (QTLs) for TELA under a single environment and estimated breeding value (EBV).  A total of eight QTLs were detected under a single environmental condition, and four QTLs were identified for EBV which also can be detected in single environment.  This indicated that the EBV-detected QTLs have high genetic stability.  A major QTL (qTELA_2-9) located in chromosome bin 2.04/2.05 could be detected in four environments and has a high phenotypic contribution rate (ranging from 10.79 to 16.51%) that making it a good target for molecular breeding.  In addition, joint analysis was used to reveal the genetic basis of leaf area in six environments.  In total, six QTL×environment interactions and nine epistatic interactions were identified.  Our results reveal that the genetic basis of the leaf area is not only mainly determined by additive effects, but also affected by epistatic effects environmental interaction effects.

Myostatin (MSTN) gene negatively controls skeletal muscle development and growth, variations of which play an important role in the regulation of skeletal muscle growth in mammals.  However, study on genetic polymorphism of MSTN gene in donkey is limited.  In this study, we screened the single nucleotide polymorphsims (SNPs) of MSTN gene in 13 Chinese donkey breeds.  Four novel SNPs (g.229T>C, g.872A>G, g.2014G>A, and g.2395C>G) were detected and genotyped by sequencing and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods.  Six haplotypes (H1–H6) were analyzed, which indicated abundant haplotype diversities in Chinese donkeys.  The haplotype H1 was the most dominant and ancient in all breeds.  Xinjiang donkey displayed the highest haplotype diversity.  The Neighbour-Joining (NJ) tree of MSTN gene among different species was constructed.  The clustering result of nine species was consistent with the fact of species differentiation.  Our results will provide a reliable theoretical basis for the preservation, exploration and utilization of Chinese donkey genetic resources.

During meiosis in flowering plants, degradation of the callose wall in tetrads releases newly produced microspores, which develop into mature pollen grains. In this study, we identified zbs1, a male-sterile mutant of naked oat (Avena nuda L.) that displayed complete spikelet sterility due to inviable mature pollen. The abnormal pollen grains originated from microspores with a defective callose wall and cell plate during meiosis. The defective callose wall and cell plate of the zbs1 mutant were detected by the labeling of cell wall epitopes (β-1,3-glucan) with immunogold during meiosis, and an abnormal chromosome configuration was observed by propidium iodide staining. The mature pollen grains of the zbs1 mutant were irregular in shape, and abnormal germination was observed by scanning electron microscopy. Together, our results indicate that the cause of male sterility in zbs1 is abnormal meiosis.

    Interspecific hybridization is an important approach to improve cultivated peanut varieties. Cytological markers such as tandem repeats will facilitate alien gene introgression in peanut. Telomeric repeats have also been frequently used in chromosome research. Most plant telomeric repeats are (TTTAGGG)_n that are mainly distributed at the chromosome ends, although interstitial telomeric repeats (ITRs) are also commonly identified. In this study, the telomeric repeat was chromosomally localized in 10 Arachis species through sequential GISH (genomic in situ hybridization) and FISH (fluorescence in situ hybridization) combined with 4’,6-diamidino-2-phenylindole (DAPI) staining. Six ITRs were identified such as in the centromeric region of chromosome Bⁱ5 in Arachis ipaënsis, pericentromeric regions of chromosomes A^s5 in A. stenosperma, B^ho7 in A. hoehnei and A^v5 in A. villosa, nucleolar organizer regions of chromosomes A^s3 in A. stenosperma and A^di3 in A. diogoi, subtelomeric regions of chromosomes B^ho9 in A. hoehnei and A^du7 in A. duranensis, and telomeric region of chromosome E^s7 in A. stenophylla. The distributions of the telomeric repeat, 5S rDNA, 45S rDNA and DAPI staining pattern provided not only ways of distinguishing different chromosomes, but also karyotypes with a higher resolution that could be used in evolutionary genome research. The distribution of telomeric repeats, 5S rDNA and 45S rDNA sites in this study, along with inversions detected on the long arms of chromosomes K^b10 and B^ho10, indicated frequent chromosomal rearrangements during evolution of Arachis species.

We investigated the correlation between leaf/soil minerals and fruit quality in apple trees grown in orchards, with the ultimate goal of improving the latter. Leaf mineral nutrients; soil nutrients in the 0–20, 20–40, and 40–60 cm layers; and fruit quality traits in 32 apple orchards in China were monitored for 2 years. Significant factors associated with fruit quality were identified via correlation analysis. An analysis of leaf data revealed that leaf nitrogen (N) and leaf magnesium (Mg) levels were extremely high in 75 and 89% of the orchards, respectively. In the Bohai Gulf region, 94% of the orchards showed significantly higher values than the standard. The soil pH values of the orchards in eastern China like eastern Shandong or Liaoning were lower than 7.0, while the pH values in the Loess Plateau of northwestern China like Shaanxi were much higher than 7. Soil alkali-hydrolyzable N levels in 47% of the orchards were lower than the optimal level of 70 mg kg–1. Generally, the soil alkali-hydrolyzable N levels of orchards in the Bohai Gulf region were significantly higher than those in the Loess Plateau region. The available P levels in the orchards of the Bohai Gulf region were up to three times higher than those of the Loess Plateau region. However, although the available potassium (K) in most orchards was sufficient (51.39–309.94 mg kg–1), leaf K content in 73% of the orchards was low, possibly due to fruit bagging or fruit overload. Approximately 63% of the orchards in Shandong and 29% of the orchards in Shannxi showed leaf Fe deficiencies. In the Loess Plateau, most orchards showed high leaf Ca levels, a strong correlation was observed between leaf and soil phosphorus/potassium (P/K) content and fruit organic acid content. The amounts of fruit soluble sugar or fructose were positively correlated with soil calcium/potassium (Ca/K) levels and leaf calcium/boron (Ca/B) levels in most orchards. The excessive leaf N levels caused by the extensive application of N fertilizers had a negative effect on fruit quality in most apple orchards in China. P, K, Ca, and B were key minerals associated with fruit quality.

This study aims to investigate the variation in occurrence of white-belly rice kernel (WBRK) and white-core rice kernel (WCRK) among different positions within a panicle. Twenty-four M4 mutants involved in four panicle types, namely the compact, intermediate, loose, and chicken foot panicle were used. They derived from a japonica rice cultivar Wuyujing 3. Considerable differences in morphological characters existed among the four types of panicle, especially in panicle length, the secondary branch number and ratio of grain number to total branch length. Marked differences were found in WBRK and WCRK among different positions within a panicle for all types of panicle. In general, grains located on the primary rachis and top rachis branches had higher WBRK and WCRK percentage than those on the secondary rachis and bottom rachis branches. WCRK exhibited larger variation among grain positions than WBRK did. Moreover, there was a significant difference in WCRK/WBRK among grain positions within a panicle, with primary rachis and top rachis branches having higher values than the secondary and bottom rachis. In addition, panicle type showed no significant effect on the pattern of WBRK and WCRK occurrence within a panicle. The results indicated the difference in mechanism of WBRK and WCRK formation in grain position within a panicle, and are valuable for breeding and agronomic practices aimed at lowering chalky grain rate.

Segregation analysis of the mixed genetic model of major gene plus polygene was used to identify the major genes for cotton yield-related traits using six generations P1, P2, F1, B1, B2, and F2 generated from the cross of Baimian 1 × TM-1. In addition to boll size and seed index, the major genes for the other five traits were detected: one each for seed yield, lint percentage, boll number, lint index; and two for lint yield. Quantitative trait locus/loci (QTL) mapping was performed in the F2 and F2:3 populations of above cross through molecular marker technology, and a total of 50 QTL (26 suggestive and 24 significant) for yield-related traits were detected. Four common QTL were discovered: qLP-3b(F2)/qLP-3(F2:3) and qLP-19b (F2)/qLP-19(F2:3) for lint percentage, qBN-17(F2)/qBN-17(F2:3) for boll number, and qBS-26b(F2)/qBS-26(F2:3) for boll size. Especially, qLP- 3b(F2)/qLP-3(F2:3), not only had LOD scores >3 but also exceeded the permutation threshold (5.13 and 5.29, respectively), correspondingly explaining 23.47 and 29.55% of phenotypic variation. This QTL should be considered preferentially in marker assisted selection (MAS). Segregation analysis and QTL mapping could mutually complement and verify, which provides a theoretical basis for genetic improvement of cotton yield-related traits by using major genes (QTL).

Protein and starch are the most important traits in determining processing quality in wheat. In order to understand the genetic basis of the influence of Waxy protein (Wx) and high molecular weight gluten subunit (HMW-GS) on processing quality, 256 recombinant inbred lines (RILs) derived from the cross of waxy wheat Nuomai 1 and Gaocheng 8901 were used as mapping population. DArT (diversity arrays technology), SSR (simple sequence repeat), HMW-GS, and Wx markers were used to construct the molecular genetic linkage map. QTLs for mixing peak time (MPT), mixing peak value (MPV), mixing peak width (MPW), and mixing peak integral (MPI) of Mixograph parameters were evaluated in three different environments. The genetic map comprised 498 markers, including 479 DArT, 14 SSR, 2 HMW-GS, and 3 Wx protein markers, covering 4 229.7 cM with an average distance of 9.77 cM. These markers were identified on 21 chromosomes. Eighteen additive QTLs were detected in three different environments, which were distributed on chromosomes 1A, 1B, 1D, 4A, 6A, and 7D. QMPT-1D.1 and QMPT-1D.2 were close to the Glu-D1 marker accounting for 35.2, 22.22 and 36.57% of the phenotypic variance in three environments, respectively. QMPV-1D and QMPV-4A were detected in all environments, and QMPV-4A was the nearest to Wx-B1. One minor QTL, QMPI-1A, was detected under three environments with the genetic distances of 0.9 cM from the nearest marker Glu-A1, explaining from 5.31 to 6.67% of the phenotypic variance. Three pairs of epistatic QTLs were identified on chromosomes 2D and 4A. Therefore, this genetic map is very important and useful for quality trait related QTL mapping in wheat. In addition, the finding of several major QTLs, based on the genetic analyses, further suggested the importance of Glu-1 loci on dough mixing characteristics.

The free putrescine (Put) content, the hydrogen peroxide (H2O2) content and the polyamine oxidase (PAO) activity in roots of Malus hupehensis Rehd. var. pinyiensis Jiang (PYTC) were significantly increased, and reached its peak at 1, 2 and 6 h, respectively, under cadmium treatment. The free spermine (Spm) and spermidine (Spd) contents were dramatically decreased, and reached the minimum value at 4-6 h, then remained relatively stable. The change in total free polyamines (PAs) content was consistent with that of free Put. The number of root dead cells was gradually increased after treatment for 24 h, and the typical characteristics of programmed cell death (PCD) were displayed at 48 h. Throughout the Cd treatment process, changes in PAs metabolism appeared to be prior to cell death increase, and the H2O2 content was always maintained at a high level. These results indicated that polyamines could initiate cell death by generating H2O2 in roots of Malus hupehensis Rehd. under CdSO4 stress.

The joint analysis of the mixed genetic model of major gene and polygene was conducted to study the inheritance of cryotolerance in cotton during the overwintering period. H077 (G. hirsutum L., weak cryotolerance) and H113 (G. barbadence L., strong cryotolerance) were used as parents. Cryotolerance of six generation populations including P1, P2, F1, B1, B2, and F2, from each of the two reciprocal crosses H077×H113 and H113×H077 were all investigated. The results showed that cryotolerance in cotton during the overwintering period was accorded with two additive major genes and additivedominance polygene genetic model. For cross H077×H113, the heritabilities of major genes in B1, B2, and F2 were 83.62, 76.84, and 90.56%, respectively; and the heritability of polygene could only be detected in B2, which was 7.76%. For cross H113×H077, the heritabilities of major genes in B1, B2, and F2 were 67.42, 68.95, and 83.40%, respectively; and the heritability of polygene was only detected in F2, which was 6.51%. In addition, the whole heritability in F2 was always higher than that in B1 and B2 in each cross. Therefore, for the cryotolerance breeding of perennial cotton, the method of single cross recombination or single backcross should be adopted to transfer major genes, and the selection in F2 would be more efficient than that in other generations.

As one of the most effective enzymatic modification methods of protein, papain hydrolysis is applied widely in food production, accompanying starch pasting frequently in order to improve industrial quality. Effects of the papain hydrolysis on flour pasting properties were investigated in five papain/flour concentrations and five time-treatments. The structure of starch and protein networks in slurry was investigated under microscope before and after pasting. Results showed that papain hydrolysis influenced the pasting properties of wheat flour significantly through affecting structural characteristics, amylase activity and exothermic transition, especially during the early stage of hydrolysis. Peak viscosity, trough, final, integral area, and setback significantly decreased along with the increasing concentration of papain. Both hydrolysis time and concentration of papain had obviously effect on the breakdown. Pasting temperature and pasting time increased significantly with the enhancement of papain concentration. Hydrolysis time exerted minor effect on the pasting temperature and pasting time. The average peak time was slightly prolonged by lower concentration of papain, otherwise slightly shortened by higher concentration.

Classical swine fever (CSF) and porcine reproduction and respiratory syndrome (PRRS) are both economically important, highly contagious diseases of swine worldwide. To develop an effective vaccine to control these two diseases, we constructed a recombinant adenovirus rAdV-GP52AE2, using a replication-defective human adenovirus serotype 5 as a delivery vector, to co-express the GP5 protein of highly pathogenic porcine reproduction and respiratory syndrome virus (PRRSV) and the E2 protein of classical swine fever virus (CSFV). Foot-and-mouth disease virus (FMDV) 2A peptide was used as a linker between the GP5 and E2 proteins to allow automatic self-cleavage of the polyprotein. The GP5 and E2 genes were expressed as demonstrated by immunofluorescence assay and Western blotting. Immunization of mice resulted in a CSFV-neutralizing antibody titer of 1:128 and a PRRSV-neutralizing antibody titer of 1:16. The lymphoproliferative responses were detected by Cell Counting Kit-8 assay and the stimulation index of CFSV-specific and PRRSV-specific lymphocytes in the rAdV-GP52AE2 group was significantly higher than that in the negative control group. The results show that rAdV-GP52AE2 can induce both effective humoral and cell-mediated immune responses in mice. The protective efficacy of the recombinant virus against CSF was evaluated in immunized rabbits, which were protected from fever induced by challenge with C-strain. Our study provides supporting evidence for the use of FMDV 2A to develop a bivalent genetically-engineered vaccine.

Peanut kernels rich in oil, particularly those with oleic acid as their primary fatty acid, are sought after by consumers, the food industry, and farmers due to their superior nutritional content, extended shelf life, and health benefits.  The oil content and fatty acid composition are governed by multiple genetic factors.  Identifying the quantitative trait loci (QTL) related to these attributes would facilitate marker-assisted selection or genomic selection, thus enhancing the quality-focused peanut breeding program.  For this purpose, we developed a population of 521 recombinant inbred lines (RIL) and tested their kernel quality traits across five different environments. We identified two major and stable QTLs for oil content (qOCAh12.1 and qOCAh16.1).  The markers linked to these QTLs were designed by competitive allele-specific PCR (KASP) and were subsequently validated.  Moreover, we found that the superior haplotype of oil content in the qOCAh16.1 region was conserved within the PI germplasm cluster, as evidenced by a diverse peanut accession panel.  In addition, we determined that qAh09 and qAh19.1, which harbor the key gene encoding fatty acid desaturase 2 (FAD2), influence all seven fatty acids, including palmitic, stearic, oleic, linoleic, arachidic, gadoleic, and behenic acids.  As for protein content and the long-chain saturated fatty acid behenic acid, qAh07 emerged as the major and stable QTLs, accounting for over 10% of the phenotypic variation explained (PVE).  These findings would enhance marker-assisted selection in peanut breeding, aiming to improve oil content, and deepen our understanding of the genetic mechanisms that shape fatty acid composition.