Pyrus pyrifolia,commonly known as sand pear,is a key economic fruit tree in temperate regions that possesses highly diverse germplasm resources for pear quality improvement.However,research on the relationship between...Pyrus pyrifolia,commonly known as sand pear,is a key economic fruit tree in temperate regions that possesses highly diverse germplasm resources for pear quality improvement.However,research on the relationship between resistance and fruit quality traits in the breeding of fruit species like pear is limited.Pan-transcriptomes effectively capture genetic information from coding regions and reflect variations in gene expression between individuals.Here,we constructed a pan-transcriptome based on 506 samples from different tissues of sand pear,and explored the intrinsic relationships among phenotypes and the selection for disease resistance during improvement based on expression presence/absence variations(eP AVs).The pan-transcriptome in this study contains 156,744 transcripts,among which the novel transcripts showed significant enrichment in the defense response.Interestingly,disease resistance genes are highly expressed in landraces of pear but have been selected against during the improvement of this perennial tree species.We found that the genetically diverse landraces can be divided into two subgroups and inferred that they have undergone different dispersal processes.Through co-expression network analysis,we confirmed that the formation of stone cells in pears,the synthesis of fruit anthocyanins,and the ability to resist stress are interrelated.They are jointly regulated by several modules,and the expression of regulatory genes has significant correlations with these three processes.Moreover,we identified candidate genes such as HKL1 that may affect sugar content and are missing from the reference genome.This study provides insights into the associations between complex fruit traits,while providing a database resource for pear disease resistance and fruit quality breeding.展开更多
Red fruit peel is one of pear's most valuable economic traits and is mainly determined by anthocyanins.Many pear cultivars with a red peel originated from bud sports;however,little is known about the genetic mecha...Red fruit peel is one of pear's most valuable economic traits and is mainly determined by anthocyanins.Many pear cultivars with a red peel originated from bud sports;however,little is known about the genetic mechanisms underlying this trait.We have previously identified a mutant Pp BBX24 containing a 14-nucleotide deletion in the coding region(Ppbbx24-del)as the only known variant associated with the red coloration of the mutant‘Red Zaosu'pear(Pyrus pyrifolia White Pear Group).Herein,we analyzed the role of the mutant gene in red coloration and its mechanism of action.The results showed that light promoted red peel coloration in the‘Red Zaosu'pear,and Ppbbx24-del positively affected light-induced anthocyanin biosynthesis,while normal Pp BBX24 had the opposite effects.Transient and stable transformation experiments confirmed that Ppbbx24-del could promote anthocyanin accumulation in pear fruit peels,calli,and tobacco flowers.Due to the loss of nuclear localization sequence(NLS)and viral protein(VP)domains,Ppbbx24-del co-localized in the nucleus and cytoplasm,whereas PpBBX24 localized only in the nucleus.Real-time PCR and transcriptome analyses indicated that PpM YB10 and PpH Y5 are highly expressed in the‘Red Zaosu'pear.In yeast one-hybrid and dual-luciferase assays,Ppbbx24-del and PpHY5 independently promoted the expression of PpC HS,PpC HI,and PpM YB10 by binding to their promoters;however,PpBBX24 did not affect the expression of these genes.Additionally,we found that Ppbbx24-del and PpHY5 had additive effects on the expression of PpC HS,PpC HI,and PpMYB10,as they promote the expression of anthocyanin synthesis genes separately.The co-expression of PpB BX24 and PpHY5 inhibited the activation of downstream genes by PpHY5,which was attributed to the interaction between the two loci.In conclusion,our results clarify the molecular mechanism by which mutant Ppbbx24-del and PpBBX24 exert opposite effects in regulating anthocyanin accumulation in pear.These findings lay an important theoretical foundation for using Ppbbx24-del to create red pear cultivars.展开更多
Pyrus pyrifolia Nakai‘Whangkeumbae'is a sand pear fruit with excellent nutritional quality and taste.However,the industrial development of pear fruit is significantly limited by its short shelf life.Salicylic aci...Pyrus pyrifolia Nakai‘Whangkeumbae'is a sand pear fruit with excellent nutritional quality and taste.However,the industrial development of pear fruit is significantly limited by its short shelf life.Salicylic acid(SA),a well-known phytohormone,can delay fruit senescence and improve shelf life.However,the mechanism by which SA regulates CONSTANS-LIKE genes(COLs)during fruit senescence and the role of COL genes in mediating fruit senescence in sand pear are poorly understood.In this study,22 COL genes were identified in sand pear,including four COLs(Pp COL8,Pp COL9a,Pp COL9b,and Pp COL14)identified via transcriptome analysis and 18 COLs through genome-wide analysis.These COL genes were divided into three subgroups according to the structural domains of the COL protein.Pp COL8,with two B-box motifs and one CCT domain,belonged to the first subgroup.In contrast,the other three Pp COLs,Pp COL9a,Pp COL9b,and Pp COL14,with similar conserved protein domains and gene structures,were assigned to the third subgroup.The four COLs showed different expression patterns in pear tissues and were preferentially expressed at the early stage of fruit development.Moreover,the expression of Pp COL8 was inhibited by exogenous SA treatment,while SA up-regulated the expression of Pp COL9a and Pp COL9b.Interestingly,Pp COL8 interacts with Pp MADS,a MADS-box protein preferentially expressed in fruit,and SA up-regulated its expression.While the production of ethylene and the content of malondialdehyde(MDA)were increased in Pp COL8-overexpression sand pear fruit,the antioxidant enzyme(POD and SOD)activity and the expression of Pp POD1 and Pp SOD1 in the sand pear fruits were down-regulated,which showed that Pp COL8 promoted sand pear fruit senescence.In contrast,the corresponding changes were the opposite in Pp MADS-overexpression sand pear fruits,suggesting that Pp MADS delayed sand pear fruit senescence.The co-transformation of Pp COL8 and Pp MADS also delayed sand pear fruit senescence.The results of this study revealed that Pp COL8 can play a key role in pear fruit senescence by interacting with Pp MADS through the SA signaling pathway.展开更多
The lack of a suitable rootstock to control scion growth has limited the development of high-density plantations in pear production, which is partly attributed to poor understanding of the dwarfing mechanism. In the p...The lack of a suitable rootstock to control scion growth has limited the development of high-density plantations in pear production, which is partly attributed to poor understanding of the dwarfing mechanism. In the present study, the rootstock of the dwarf-type pear (Pyrus betulaefolia)PY-9’ was identified and used as the material for anatomical analysis.PY-9’ grew to half the tree height of the normal cultivar Zhengdu’, along with fewer internodes and shorter length. Significant differences in growth rate betweenPY-9’ andZhengdu’ were detected at approximately 30 days after full bloom, which corresponded with the time of the greatest difference in water potential between the dwarf and normal cultivar.PY-9’ showed a higher photosynthetic rate thanZhengdu’. Anatomical analysis showed thatPY-9’ had higher area ratios of both phloem and xylem and more developed vascular tissues thanZhengdu’. The three-dimensional reconstructed skeleton of the xylem from X-ray computed tomography scanning revealed greater intervessel connectivity inZhengdu’ than inPY-9’, which could contribute to the more vigorous growth ofZhengdu’. This study thus provides the first comparison of the microstructural properties of xylem elements between a dwarfing-type and vigorous-type pear rootstock, providing new insights into the dwarfing mechanism in pear and facilitating breeding of dwarf pear rootstocks to increase crop productivity.展开更多
Pear(Pyrus bretschneideri)fruit stone cells are primarily composed of lignin and have strongly lignified cell walls.The presence of stone cells has a negative influence on fruit texture and taste,and thus the reductio...Pear(Pyrus bretschneideri)fruit stone cells are primarily composed of lignin and have strongly lignified cell walls.The presence of stone cells has a negative influence on fruit texture and taste,and thus the reduction of stone cell content in pear fruit is a key goal of breeding efforts.However,research into the key transcription factors and regulatory networks associated with pear fruit stone cell formation have been limited.We here used a combination of co-expression network and expression quantitative trait locus(eQTL)analyses in 206 pear cultivars with different stone cell contents to identify relevant genes;these analyses uncovered the gene PbrMYB4,a R2R3 MYB transcription factor gene.There was a strong positive correlation between relative PbrMYB4 expression levels in the fruit flesh and stone cell/lignin contents.Overexpression of PbrMYB4 significantly increased the lignin contents,whereas silencing of PbrMYB4 had the opposite effect,decreasing the contents of lignin.PbrMYB4 overexpression in pear calli significantly promoted lignin biosynthesis.In Arabidopsis thaliana,PbrMYB4 overexpression resulted in increasing lignin deposition,cell wall thickness of vessels and xylary fiber,and accelerating expression level of lignin biosynthetic genes.PbrMYB4 was found to activate 4-Coumarate:Coenzyme A Ligase(Pbr4CL1)by binding to AC-I elements in the promoter regions,as demonstrated with dual-luciferase reporter assays and a yeast one-hybrid assay.These results demonstrated that PbrMYB4 positively regulated lignin biosynthesis in pear fruit stone cells by activating lignin biosynthesis genes.This study improves our understanding of the gene regulatory networks associated with stone cell formation in pear fruit,providing guidance for molecular breeding of pear varieties with low stone cell content.展开更多
The WSC proteins produced by Penicillium expansum play a crucial role in causing blue mold on pears.To analyze the role of the WSC1 gene in the pathogenic process of this fungal pathogen,we conducted transcriptomic an...The WSC proteins produced by Penicillium expansum play a crucial role in causing blue mold on pears.To analyze the role of the WSC1 gene in the pathogenic process of this fungal pathogen,we conducted transcriptomic analysis of a WSC1 knockout(ΔWSC1)strain.The knockout of WSC1 significantly altered the gene expression profile in P.expansum,particularly for genes involved in cell wall integrity,signaling,stress response,and toxin production.The differential expression of these genes might make theΔWSC1 strain more vulnerable to environmental stress,while reducing the toxin production capacity,ultimately leading to a decrease in the pathogenicity.The transcriptomic analysis revealed that the expression of genes related to stress response signals,defense mechanisms and oxidative stress management changed when pear fruits were infected with theΔWSC1 strain.These changes may trigger a cascade of responses in pear fruits.In addition,compared with those infected with the wild-type strain,pear fruits infected with theΔWSC1 strain exhibited up-regulated expression of genes related to defense and oxidative stress.This study clarifies how the WSC1 gene influences P.expansum’s ability to infect pear fruits and how pear fruits respond to the infection.展开更多
Pear paste is a traditional preparation with both medicinal and nutritional functions.The“pear”,as its core ingredient,plays a crucial role in the efficacy of the preparation.This paper,through the interdisciplinary...Pear paste is a traditional preparation with both medicinal and nutritional functions.The“pear”,as its core ingredient,plays a crucial role in the efficacy of the preparation.This paper,through the interdisciplinary integration of evidence from traditional Chinese medicine,food chemistry,molecular biology,and clinical medicine,constructs a complete“raw material-component transformation-biological regulation”model for the first time.It is found that in pear paste,pears not only serve as a functional matrix.The polysaccharide-polyphenol-triterpene complex system forms a multi-target cough-relieving and anti-inflammatory network through dual regulation of TRPV1/TRPA1 ion channels,inhibition of the NLRP3 inflammasome,and metabolites of gut microbiota such as SCFAs.The research results provide a theoretical breakthrough for the modern development of pear paste and a scientific basis for the modernization of traditional preparations.展开更多
The new late-maturing pear cultivar‘Suyu’was bred through hybrid breeding using‘Mili’as the female parent and‘Dangshansuli’as the male parent.This cultivar has a nearly round fruit shape with a greenish-yellow s...The new late-maturing pear cultivar‘Suyu’was bred through hybrid breeding using‘Mili’as the female parent and‘Dangshansuli’as the male parent.This cultivar has a nearly round fruit shape with a greenish-yellow skin,an average single fruit weight of 394.3 g,and a small core.The flesh is white,fine-textured,crisp,juicy,sweet,and aromatic,with a soluble solid content of 12.8%.The tree has a strong growth vigor,an open canopy,high budding rate,and strong branching ability,making it suitable for spindle or cylindrical cultivation.The main color of the one-year-old branches on the sunny side is brown.The young leaves are yellowish-green,and the mature leaves are ovate with sharp serrations.Each inflorescence has 5 to 7 flowers with pink petals,a pistil that protrudes above the stamens,and purple-red anthers.The fruit development period is about 150 d,and it matures in mid-to-late September in Changli,Hebei.The cultivar is high-yielding,stable,and well-suited for storage.‘Suyu’can be cultivated in pear-growing areas of Hebei Province and regions with similar ecological types.展开更多
Korla fragrant pears are one of the“famous,excellent,and special”fruits in Xinjiang.They belong to the white pear variety in the genus Pyrus of the Rosaceae family.With a long-standing planting history and strong re...Korla fragrant pears are one of the“famous,excellent,and special”fruits in Xinjiang.They belong to the white pear variety in the genus Pyrus of the Rosaceae family.With a long-standing planting history and strong regional characteristics,they are mainly produced in southern Xinjiang.Due to unique natural conditions such as large temperature differences between day and night and sufficient sunlight,Korla fragrant pears have a crispy texture,a sweet but not cloying taste,and their flesh is delicate and juicy,with excellent quality.Korla fragrant pears contain a variety of bioactive substances,mainly including polysaccharides,polyphenolic compounds,flavonoid compounds,triterpenoids,and sterols.They have medical effects such as“moistening the lungs,calming the heart,reducing phlegm,anti-inflammation,relieving cough,and resolving carbuncle toxins”.Uyghur and Mongolian medicine often use them as a good dietary therapy product.Based on recent literature reports,this paper reviews the main chemical constituents and pharmacological effects of Korla fragrant pears,aiming to provide references for the research and utilization of the deep processing of Korla fragrant pears.展开更多
In order to enhance the guidance for Yuluxiang pear cultivation in hilly and mountainous regions, this study provides a comprehensive introduction to various aspects, including the establishment of high-standard orcha...In order to enhance the guidance for Yuluxiang pear cultivation in hilly and mountainous regions, this study provides a comprehensive introduction to various aspects, including the establishment of high-standard orchards and the reinforcement of integrated management techniques, in order to offer a valuable reference for fruit farmers engaged in scientific planting practices.展开更多
Pear anthracnose,caused by Colletotrichum fructicola,is a devastating disease that seriously affects most pear varieties,compromising their yield and quality.However,effective control of this pathogen is lacking.Moreo...Pear anthracnose,caused by Colletotrichum fructicola,is a devastating disease that seriously affects most pear varieties,compromising their yield and quality.However,effective control of this pathogen is lacking.Moreover,the critical resistance responses to C.fructicola in pear are unknown.To investigate these resistance mechanisms of pear against C.fructicola,transcriptomic and metabolomic analyses were performed on the anthracnose-resistant variety‘Seli’and susceptible variety‘Cuiguan’after C.fructicola infection.Differentially expressed genes(DEGs)and differentially accumulated metabolites(DAMs)were mainly involved in metabolism and secondary metabolite synthetic pathways,includingα-linoleic acid metabolism,phenylalanine biosynthesis metabolism,unsaturated fatty acids biosynthesis,and biosynthesis of amino acids and their derivatives.In particular,the accumulation of unsaturated fatty acids(UFAs),amino acids,and their derivatives,such as linoleic acid and its derivatives,lauric acid,N-acetyl-L-glutamic acid,and L-proline,was significantly increased in‘Seli’after infection,while the amino acids of oxiglutatione and N-acetyl-L-glutamic acid,as well as the proanthocyanidins,were significantly decreased in‘Cuiguan’.These findings suggest that these metabolites may contribute to the differential anthracnose resistance between‘Seli’and‘Cuiguan’.Overall,our results provid new insights into the regulation of pear anthracnose resistance,which may assist in developing new control strategies and breeding anthracnose-resistant varieties.展开更多
Dehydrin(DHN)enhances plant resistance to environmental stress by regulating the synthesis of osmotic adjustment substances and scavenging reactive oxygen species.However,the role of PbDHN3 under salt stress remains u...Dehydrin(DHN)enhances plant resistance to environmental stress by regulating the synthesis of osmotic adjustment substances and scavenging reactive oxygen species.However,the role of PbDHN3 under salt stress remains unclear.In this study,salt stress induced high expression of PbDHN3,and the overexpression of PbDHN3(OE-PbDHN3)enhanced plant growth under salt stress compared to wild-type(WT)plants.OE-PbDHN3 plants exhibited higher chlorophyll content and root growth capacity than WT plants under salt stress.Transcriptome analysis revealed that PbDHN3 expression is associated with ethylene signaling pathways.OE-PbDHN3 transgenic plants substantially influenced ethylene content and the expression of related genes.Following treatment with exogenous ethephon,the transgenic lines notably inhibited the processes of ethylene synthesis and signaling transduction.OE-PbDHN3 transgenic lines treated with exogenous ethylene and the ethylene inhibitor 1-MCP demonstrated significant inhibition of ethylene synthesis and signaling transduction,while promoting root development and chlorophyll content.Under salt stress,OE-PbDHN3 downregulated the expression of ethylene biosynthesis genes PbACO1-like and PbACO2,and signal transduction genes PbEIN3-like during the initial stress phase.This early regulation mitigated the adverse effects of salt stress on the plants.These findings demonstrate that PbDHN3 ameliorates the ethylene-mediated plant growth phenotype under salt stress through regulation of ethylene synthesis and signal transduction.展开更多
Significant variations in global temperatures and weather patterns over time are known as climate change.Although it occurs naturally,human activities—particularly the burning of fossil fuels,deforestation,and indust...Significant variations in global temperatures and weather patterns over time are known as climate change.Although it occurs naturally,human activities—particularly the burning of fossil fuels,deforestation,and industrial processes—are accelerating these changes,which have various detrimental effects on the environment.This review aims to highlight the edapho-climatic requirements of this cactus and the advantages and challenges of its cultivation to mitigate climate change.The prickly pear cactus is a plant with numerous financial and environmental advantages.It needs well-draining,sandy or gravelly soil to avoid root rot and do best in full sun.With a strong tolerance for dryness,they thrive in arid or semi-arid regions with scorching summers and prefer sparing watering.Despite being suited to tropical climates,some species can tolerate freezing temperatures and sporadic frost.Once established,these hardy plants require little care and thrive in nutrient-poor soils,which makes them perfect for xeriscaping or challenging growing environments.Because of its high water use efficiency ratio and low water requirements,prickly pear can be grown in marginally dry and semi-arid areas.The cactus does contribute to the ecological and socioeconomic fight against climate change.For instance,it supports sustainable agriculture,biodiversity preservation,soil restoration,carbon sequestration,and effective water usage.Demarcating dry and semi-arid zones and fostering employment in these areas is beneficial from a socioeconomic standpoint.The prickly pear’s traditional cultural heritage supports its current economic function as a crop that can withstand drought.While ecological threats necessitate balanced management,this adaptability promotes sustainable growth.Innovations in bioenergy and value-added goods build on its historical applications,increasing its socioeconomic advantages and,eventually,its worldwide significance.展开更多
PpMYB10 and PpMYB114 have been identified as the key R2R3-MYB transcription factors(TFs)that positively regulate anthocyanin biosynthesis in pear.Our previous study demonstrated that the ethylene-induced Pp ERF9-Pp TP...PpMYB10 and PpMYB114 have been identified as the key R2R3-MYB transcription factors(TFs)that positively regulate anthocyanin biosynthesis in pear.Our previous study demonstrated that the ethylene-induced Pp ERF9-Pp TPL1 co-repressor complex represses the expression of PpMYB114,but not PpMYB10,via histone deacetylation.However,the precise molecular mechanism underlying the ethylene-mediated inhibition of PpMYB10 expression remains to be elucidated.The results of this study reveal a high correlation between the expression patterns of PpMYB114 and PpMYB10 in response to ethylene signaling.Moreover,PpMYB114 was found to promote the expression of PpMYB10 by directly binding to the MYB-binding site(MBS)element within its promoter region.Transient overexpression or silencing of PpMYB114 resulted in the promotion or inhibition of PpMYB10 expression in mature pear fruit,respectively.The overexpression of PpMYB114 in pear calli significantly induced PpMYB10 expression and anthocyanin biosynthesis.Conversely,transient silencing of PpMYB10 in PpMYB114-OE pear calli hindered the promotive effect of PpMYB114 on anthocyanin biosynthesis,indicating that PpMYB114 induces anthocyanin biosynthesis,which is at least partially dependent on the transcriptional activation of PpMYB10.Collectively,these results indicate that ethylene may inhibit the expression of PpMYB10 by repressing PpMYB114.Our findings provide insights into a possible mechanism involving ethylene-inhibited PpMYB10 in pear and reveal the regulatory relationship between the R2R3-MYBs involved in anthocyanin biosynthesis.展开更多
The fruit of Huangguan pear is deeply loved by consumers because of its rich nutrition and rich flavor.The quality evaluation system of Huangguan pear is composed of many quality types.In this study,the types and func...The fruit of Huangguan pear is deeply loved by consumers because of its rich nutrition and rich flavor.The quality evaluation system of Huangguan pear is composed of many quality types.In this study,the types and functions of nutritional quality indexes of Huangguan pear were summarized,such as vitamin C,soluble solids,soluble sugar and titratable acid,and the factors affecting the nutritional quality of Huangguan pear including genetic factors,environmental factors and agricultural management measures were overviewed,aiming to provide reference for establishing a comprehensive quality evaluation system of Huangguan pear and then promoting the high-quality development of Huangguan pear industry.展开更多
Pear fruit corking disorder is a non-infectious physiological condition that primarily occurs during the late developmental stages of pear and significantly impacts fruit quality and economic value in several major cu...Pear fruit corking disorder is a non-infectious physiological condition that primarily occurs during the late developmental stages of pear and significantly impacts fruit quality and economic value in several major cultivars.As the underlying mechanism remains unclear,effective prevention strategies and genetic improvements continue to present major challenges.In this study,‘Akizuki’pear was used as experimental material,and the lignin content in cork-affected tissue was found to be significantly higher than in healthy tissue.Exogenous abscisic acid(ABA)treatment induced cork formation and promoted lignin biosynthesis,a major structural component,in both pear fruits and calli.Through integrated RNA-seq and expression analyses,we identified the ABA-responsive gene PbrMYB8,which was differentially expressed between healthy and diseased tissues and associated with lignin biosynthesis during corking disorder.Stable transformation of PbrMYB8 into pear calli and Arabidopsis confirmed its role in promoting lignin biosynthesis.Notably,PbrMYB8 not only activated lignin biosynthesis genes independently but also interacted with PbrMYB169 to form a protein complex that co-regulated their expression.These findings improve our understanding of lignin biosynthesis in pear fruit corking disorder by identifying a key regulator and its interaction network and provide a theoretical foundation for future strategies aimed at improving pear fruit quality.展开更多
Genetic variation contributes to the phenotypic diversity of plants.Most red pear cultivars that accumulate anthocyanins originated from somatic variation and are termed as bud sports.‘Hongzaosu’is a bud sport deriv...Genetic variation contributes to the phenotypic diversity of plants.Most red pear cultivars that accumulate anthocyanins originated from somatic variation and are termed as bud sports.‘Hongzaosu’is a bud sport derived from the green pear‘Zaosu’.A new genetic map was constructed from a population derived from the cross of‘Yuluxiang’and‘Hongzaosu’,from which PpBBX24 was identified as a crucial gene controlling anthocyanin accumulation.Genetic and phylogenetic evidences revealed that PpBBX24 is a repressor of anthocyanin biosynthesis in pear.A 14 bp deletion was detected in the third exon of PpBBX24 in‘Hongzaosu’,resulting in premature termination of protein translation.The truncated PpBBX24 protein was a positive regulator of anthocyanin biosynthesis by activating the transcription of PpCHS and PpUFGT.Three independent variations in the BBX24 coding region that led to premature termination of translation were detected in other pear bud sports and the progeny of a bud sport that all accumulate anthocyanins.The genome of‘Hongzaosu’was assembled using both long-read and short-read sequences.By combining genomic and transcriptomic data,allele-specific expression of PpMYB110a was observed in the fruit skin of‘Hongzaosu',which was likely caused by a large variation in the promoter.This work enhances understanding of coloration in red pears and provides a novel genomic resource for further studies on‘Hongzaosu’pear.展开更多
Pear is a popular and commercially important fresh fruit, and its texture is related to the presence of sclereid formatted by parenchyma cell with lignification in vascular plants. Previous studies have demonstrated t...Pear is a popular and commercially important fresh fruit, and its texture is related to the presence of sclereid formatted by parenchyma cell with lignification in vascular plants. Previous studies have demonstrated that content of lignin may be regulated by cinnamoyl CoA reductase(CCR) in various plants. However, the function of CCR in pears remains very limited. In the present study, we isolated a cDNA encoding CCR(PpCCR, GenBank accession No. KF999958) and its promoter(proPpCCR) from Whangkeumbae pear to investigate the function of CCR in lignin biosynthesis. PpCCR-GFP expressed in rice mesophyll protoplast demonstrated that PpCCR-GFP was localized in the cytoplasm, indicating that CCR may function in cytoplasm without localization signals. In transgenic plants carrying PpCCR, we observed higher lignin content compared with that in wild type plants, further suggesting that PpCCR can affect the lignin contents through regulating lignin biosynthesis in Arabidopsis thaliana. More studies in other plants are needed to confirm our conclusion.展开更多
The identification of self-incompatibility genotype （S-genotype） will be useful for selection of pollinizers and design of crossing in cultivar improvement of sand pear. This paper reported the identification of sel...The identification of self-incompatibility genotype （S-genotype） will be useful for selection of pollinizers and design of crossing in cultivar improvement of sand pear. This paper reported the identification of self-incompatibility genotypes of seven Chinese and two Japanese sand pear cultivars using PCR-RFLP analysis and S-RNase sequencing. The Sgenotypes of these cultivars were determined as follows： Huali 1 S1S3, Shounan S1S3, Xizilti S1S4, Qingxiang S3S7, Sanhua S2S7, Huangmi （Imamuranatsu） S1S6, Huali 2 S3S4, Baozhuli S7S33, Cangxixueli S5S15. S-RNase alleles （S1 to S9） in sand pear could be identified effectively by PCR-RFLP analysis.展开更多
Germplasm resources are an important basis for genetic breeding and analysis of complex traits,and research on genetic diversity is conducive to the exploration and creation of new types of germplasm.In this study,the...Germplasm resources are an important basis for genetic breeding and analysis of complex traits,and research on genetic diversity is conducive to the exploration and creation of new types of germplasm.In this study,the distribution frequency,coefficient of variation,Shannon-Wiener index,and variance and cluster analyses were used to analyze the diversity and trait differences of 39 fruit phenotypic traits from 570 pear accessions,which included 456 pear accessions from 11 species and 114 interspecific hybrid cultivars that had been stored in the National Germplasm Repository of Apple and Pear(Xingcheng,China).The comprehensive evaluation indices were screened by correlation,principal component and regression analyses.A total of 132 variant types were detected in 28 categorical traits of pear germplasm fruit,which indicate a rich diversity.The diversity indices in decreasing order were:fruit shape(1.949),attitude of calyx(1.908),flesh texture type(1.700),persistency of calyx(1.681),russet location(1.658),relief of area around eye basin(1.644),flavor(1.610)and ground color(1.592).The coefficient of variation of titratable acidity in the 11 numerical traits of pear germplasm fruit was as high as 128.43%,which could more effectively reflect the differences between pear accessions.The phenotypic differentiation coefficient V_(st)(66.4%)among the five cultivated pear species,including Pyrus bretschneideri(White Pear),P.pyrifolia(Sand Pear),P.ussuriensis(Ussurian Pear),P.sinkiangensis(Xinjiang Pear),and P.communis(European Pear),was higher than the within population phenotypic differentiation coefficient V_(st)(33.6%).The variation among populations was the main source of variation in pear fruit traits.A hierarchical cluster analysis divided the 389 accessions of six cultivated pear species,including P.pashia(Himalayan Pear),into six categories.There were certain characteristics within the populations,and the differences between populations were not completely clustered by region.For example,Sand Pear cultivars from Japan and the Korean Peninsula clustered together with those from China.Most of the White Pear cultivars clustered with the Sand Pear,and a few clustered with the Ussurian Pear cultivars.The Ussurian Pear and European Pear cultivars clustered separately.The Xinjiang Pear and Himalayan Pear did not cluster together,and neither did the cultivars.Seventeen traits,three describing fruit weight and edible rate(fruit diameter,fruit length and fruit core size),five describing outer quality and morphological characteristics(over color,amount of russeting,dot obviousness,fruit shape,and stalk length),and nine describing inner quality(flesh color,juiciness of flesh,aroma,flavor,flesh texture,flesh texture type,soluble solid contents,titratable acidity,and eating quality)were selected from the 39 traits by principal component and stepwise regression analyses.These 17 traits could reflect 99.3%of the total variation and can be used as a comprehensive evaluation index for pear germplasm resources.展开更多
基金supported by the National Science Foundation of China(32230097)the National Key Research and Development Program of China(2022YFD1200503)+2 种基金the earmarked fund for China Agriculture Research System(CARS-28)the earmarked fund for Jiangsu Agricultural Industry Technology System(JATS[2023]412)the Natural Science Foundation of Jiangsu Province for Young Scholar,China(BK20221010)。
文摘Pyrus pyrifolia,commonly known as sand pear,is a key economic fruit tree in temperate regions that possesses highly diverse germplasm resources for pear quality improvement.However,research on the relationship between resistance and fruit quality traits in the breeding of fruit species like pear is limited.Pan-transcriptomes effectively capture genetic information from coding regions and reflect variations in gene expression between individuals.Here,we constructed a pan-transcriptome based on 506 samples from different tissues of sand pear,and explored the intrinsic relationships among phenotypes and the selection for disease resistance during improvement based on expression presence/absence variations(eP AVs).The pan-transcriptome in this study contains 156,744 transcripts,among which the novel transcripts showed significant enrichment in the defense response.Interestingly,disease resistance genes are highly expressed in landraces of pear but have been selected against during the improvement of this perennial tree species.We found that the genetically diverse landraces can be divided into two subgroups and inferred that they have undergone different dispersal processes.Through co-expression network analysis,we confirmed that the formation of stone cells in pears,the synthesis of fruit anthocyanins,and the ability to resist stress are interrelated.They are jointly regulated by several modules,and the expression of regulatory genes has significant correlations with these three processes.Moreover,we identified candidate genes such as HKL1 that may affect sugar content and are missing from the reference genome.This study provides insights into the associations between complex fruit traits,while providing a database resource for pear disease resistance and fruit quality breeding.
基金National Natural Science Foundation of China(32072531)the Agricultural Science and Technology Innovation Program of the Chinese Academy of Agricultural Sciences(CAAS-ASTIP-2016-RIP)+2 种基金the National Key Research and Development Program of China(2021YFE0190700)the ScienceTechnology&Innovation Funding Authority(STDF)of Egypt(43093)for funding this work。
文摘Red fruit peel is one of pear's most valuable economic traits and is mainly determined by anthocyanins.Many pear cultivars with a red peel originated from bud sports;however,little is known about the genetic mechanisms underlying this trait.We have previously identified a mutant Pp BBX24 containing a 14-nucleotide deletion in the coding region(Ppbbx24-del)as the only known variant associated with the red coloration of the mutant‘Red Zaosu'pear(Pyrus pyrifolia White Pear Group).Herein,we analyzed the role of the mutant gene in red coloration and its mechanism of action.The results showed that light promoted red peel coloration in the‘Red Zaosu'pear,and Ppbbx24-del positively affected light-induced anthocyanin biosynthesis,while normal Pp BBX24 had the opposite effects.Transient and stable transformation experiments confirmed that Ppbbx24-del could promote anthocyanin accumulation in pear fruit peels,calli,and tobacco flowers.Due to the loss of nuclear localization sequence(NLS)and viral protein(VP)domains,Ppbbx24-del co-localized in the nucleus and cytoplasm,whereas PpBBX24 localized only in the nucleus.Real-time PCR and transcriptome analyses indicated that PpM YB10 and PpH Y5 are highly expressed in the‘Red Zaosu'pear.In yeast one-hybrid and dual-luciferase assays,Ppbbx24-del and PpHY5 independently promoted the expression of PpC HS,PpC HI,and PpM YB10 by binding to their promoters;however,PpBBX24 did not affect the expression of these genes.Additionally,we found that Ppbbx24-del and PpHY5 had additive effects on the expression of PpC HS,PpC HI,and PpMYB10,as they promote the expression of anthocyanin synthesis genes separately.The co-expression of PpB BX24 and PpHY5 inhibited the activation of downstream genes by PpHY5,which was attributed to the interaction between the two loci.In conclusion,our results clarify the molecular mechanism by which mutant Ppbbx24-del and PpBBX24 exert opposite effects in regulating anthocyanin accumulation in pear.These findings lay an important theoretical foundation for using Ppbbx24-del to create red pear cultivars.
基金supported by the National Natural Science Foundation of China(32272654)the Natural Science Foundation of Hebei Province China(C2023204016)+2 种基金the Hebei Province Introduced Overseas-Scholar Fund China(C20220361)the S&T Program of Hebei China(20326330D)the Hebei Province Outstanding Youth Fund China(2016,2019)。
文摘Pyrus pyrifolia Nakai‘Whangkeumbae'is a sand pear fruit with excellent nutritional quality and taste.However,the industrial development of pear fruit is significantly limited by its short shelf life.Salicylic acid(SA),a well-known phytohormone,can delay fruit senescence and improve shelf life.However,the mechanism by which SA regulates CONSTANS-LIKE genes(COLs)during fruit senescence and the role of COL genes in mediating fruit senescence in sand pear are poorly understood.In this study,22 COL genes were identified in sand pear,including four COLs(Pp COL8,Pp COL9a,Pp COL9b,and Pp COL14)identified via transcriptome analysis and 18 COLs through genome-wide analysis.These COL genes were divided into three subgroups according to the structural domains of the COL protein.Pp COL8,with two B-box motifs and one CCT domain,belonged to the first subgroup.In contrast,the other three Pp COLs,Pp COL9a,Pp COL9b,and Pp COL14,with similar conserved protein domains and gene structures,were assigned to the third subgroup.The four COLs showed different expression patterns in pear tissues and were preferentially expressed at the early stage of fruit development.Moreover,the expression of Pp COL8 was inhibited by exogenous SA treatment,while SA up-regulated the expression of Pp COL9a and Pp COL9b.Interestingly,Pp COL8 interacts with Pp MADS,a MADS-box protein preferentially expressed in fruit,and SA up-regulated its expression.While the production of ethylene and the content of malondialdehyde(MDA)were increased in Pp COL8-overexpression sand pear fruit,the antioxidant enzyme(POD and SOD)activity and the expression of Pp POD1 and Pp SOD1 in the sand pear fruits were down-regulated,which showed that Pp COL8 promoted sand pear fruit senescence.In contrast,the corresponding changes were the opposite in Pp MADS-overexpression sand pear fruits,suggesting that Pp MADS delayed sand pear fruit senescence.The co-transformation of Pp COL8 and Pp MADS also delayed sand pear fruit senescence.The results of this study revealed that Pp COL8 can play a key role in pear fruit senescence by interacting with Pp MADS through the SA signaling pathway.
基金supported by grants from the Agriculture Science and Technology of Shandong Province (Grant No.2019YQ015)the Agricultural Variety Improvement Project of Shandong Province (Grant No.2022LZGC011)the earmarked fund for CARS (Grant No.CARS-28-07)。
文摘The lack of a suitable rootstock to control scion growth has limited the development of high-density plantations in pear production, which is partly attributed to poor understanding of the dwarfing mechanism. In the present study, the rootstock of the dwarf-type pear (Pyrus betulaefolia)PY-9’ was identified and used as the material for anatomical analysis.PY-9’ grew to half the tree height of the normal cultivar Zhengdu’, along with fewer internodes and shorter length. Significant differences in growth rate betweenPY-9’ andZhengdu’ were detected at approximately 30 days after full bloom, which corresponded with the time of the greatest difference in water potential between the dwarf and normal cultivar.PY-9’ showed a higher photosynthetic rate thanZhengdu’. Anatomical analysis showed thatPY-9’ had higher area ratios of both phloem and xylem and more developed vascular tissues thanZhengdu’. The three-dimensional reconstructed skeleton of the xylem from X-ray computed tomography scanning revealed greater intervessel connectivity inZhengdu’ than inPY-9’, which could contribute to the more vigorous growth ofZhengdu’. This study thus provides the first comparison of the microstructural properties of xylem elements between a dwarfing-type and vigorous-type pear rootstock, providing new insights into the dwarfing mechanism in pear and facilitating breeding of dwarf pear rootstocks to increase crop productivity.
基金funded by the Science Foundation of China(Grant No.32230097)Earmarked Fund for China Agriculture Research System(Grant No.CARS-28)+2 种基金the Earmarked Fund for Jiangsu Agricultural Industry Technology System(Grant No.JATS[2023]412)Natural Science Foundation of Jiangsu Province for Young Scholar(Grant No.BK20221010)supported by the high-performance computing platform of Bioinformatics Center,Nanjing Agricultural University。
文摘Pear(Pyrus bretschneideri)fruit stone cells are primarily composed of lignin and have strongly lignified cell walls.The presence of stone cells has a negative influence on fruit texture and taste,and thus the reduction of stone cell content in pear fruit is a key goal of breeding efforts.However,research into the key transcription factors and regulatory networks associated with pear fruit stone cell formation have been limited.We here used a combination of co-expression network and expression quantitative trait locus(eQTL)analyses in 206 pear cultivars with different stone cell contents to identify relevant genes;these analyses uncovered the gene PbrMYB4,a R2R3 MYB transcription factor gene.There was a strong positive correlation between relative PbrMYB4 expression levels in the fruit flesh and stone cell/lignin contents.Overexpression of PbrMYB4 significantly increased the lignin contents,whereas silencing of PbrMYB4 had the opposite effect,decreasing the contents of lignin.PbrMYB4 overexpression in pear calli significantly promoted lignin biosynthesis.In Arabidopsis thaliana,PbrMYB4 overexpression resulted in increasing lignin deposition,cell wall thickness of vessels and xylary fiber,and accelerating expression level of lignin biosynthetic genes.PbrMYB4 was found to activate 4-Coumarate:Coenzyme A Ligase(Pbr4CL1)by binding to AC-I elements in the promoter regions,as demonstrated with dual-luciferase reporter assays and a yeast one-hybrid assay.These results demonstrated that PbrMYB4 positively regulated lignin biosynthesis in pear fruit stone cells by activating lignin biosynthesis genes.This study improves our understanding of the gene regulatory networks associated with stone cell formation in pear fruit,providing guidance for molecular breeding of pear varieties with low stone cell content.
文摘The WSC proteins produced by Penicillium expansum play a crucial role in causing blue mold on pears.To analyze the role of the WSC1 gene in the pathogenic process of this fungal pathogen,we conducted transcriptomic analysis of a WSC1 knockout(ΔWSC1)strain.The knockout of WSC1 significantly altered the gene expression profile in P.expansum,particularly for genes involved in cell wall integrity,signaling,stress response,and toxin production.The differential expression of these genes might make theΔWSC1 strain more vulnerable to environmental stress,while reducing the toxin production capacity,ultimately leading to a decrease in the pathogenicity.The transcriptomic analysis revealed that the expression of genes related to stress response signals,defense mechanisms and oxidative stress management changed when pear fruits were infected with theΔWSC1 strain.These changes may trigger a cascade of responses in pear fruits.In addition,compared with those infected with the wild-type strain,pear fruits infected with theΔWSC1 strain exhibited up-regulated expression of genes related to defense and oxidative stress.This study clarifies how the WSC1 gene influences P.expansum’s ability to infect pear fruits and how pear fruits respond to the infection.
基金Science and Technology Achievements Transformation Project of the Autonomous Prefecture(Project No.:202401)National College Students'Innovation and Entrepreneurship Training Program(Project Title:"Li Zhiyun·Ku Li Chun"-Pioneer in Promoting National Geographic Brand,Project Number:202513561005).
文摘Pear paste is a traditional preparation with both medicinal and nutritional functions.The“pear”,as its core ingredient,plays a crucial role in the efficacy of the preparation.This paper,through the interdisciplinary integration of evidence from traditional Chinese medicine,food chemistry,molecular biology,and clinical medicine,constructs a complete“raw material-component transformation-biological regulation”model for the first time.It is found that in pear paste,pears not only serve as a functional matrix.The polysaccharide-polyphenol-triterpene complex system forms a multi-target cough-relieving and anti-inflammatory network through dual regulation of TRPV1/TRPA1 ion channels,inhibition of the NLRP3 inflammasome,and metabolites of gut microbiota such as SCFAs.The research results provide a theoretical breakthrough for the modern development of pear paste and a scientific basis for the modernization of traditional preparations.
基金Supported by Hebei Provincial Key Research and Development Program(21326308D-1-2)Hebei Provincial High-Level Talent Support Program(C20231157)Basic Research Funds of Hebei Academy of Agriculture and Forestry Sciences(2024020202).
文摘The new late-maturing pear cultivar‘Suyu’was bred through hybrid breeding using‘Mili’as the female parent and‘Dangshansuli’as the male parent.This cultivar has a nearly round fruit shape with a greenish-yellow skin,an average single fruit weight of 394.3 g,and a small core.The flesh is white,fine-textured,crisp,juicy,sweet,and aromatic,with a soluble solid content of 12.8%.The tree has a strong growth vigor,an open canopy,high budding rate,and strong branching ability,making it suitable for spindle or cylindrical cultivation.The main color of the one-year-old branches on the sunny side is brown.The young leaves are yellowish-green,and the mature leaves are ovate with sharp serrations.Each inflorescence has 5 to 7 flowers with pink petals,a pistil that protrudes above the stamens,and purple-red anthers.The fruit development period is about 150 d,and it matures in mid-to-late September in Changli,Hebei.The cultivar is high-yielding,stable,and well-suited for storage.‘Suyu’can be cultivated in pear-growing areas of Hebei Province and regions with similar ecological types.
基金Science and Technology Achievements Transformation Project of the Autonomous Prefecture(Project No.:202401)National College Students'Innovation and Entrepreneurship Training Program(Project Title:"Li Zhiyun·Ku Li Chun"-Pioneer in Promoting National Geographic Brand,Project Number:202513561005).
文摘Korla fragrant pears are one of the“famous,excellent,and special”fruits in Xinjiang.They belong to the white pear variety in the genus Pyrus of the Rosaceae family.With a long-standing planting history and strong regional characteristics,they are mainly produced in southern Xinjiang.Due to unique natural conditions such as large temperature differences between day and night and sufficient sunlight,Korla fragrant pears have a crispy texture,a sweet but not cloying taste,and their flesh is delicate and juicy,with excellent quality.Korla fragrant pears contain a variety of bioactive substances,mainly including polysaccharides,polyphenolic compounds,flavonoid compounds,triterpenoids,and sterols.They have medical effects such as“moistening the lungs,calming the heart,reducing phlegm,anti-inflammation,relieving cough,and resolving carbuncle toxins”.Uyghur and Mongolian medicine often use them as a good dietary therapy product.Based on recent literature reports,this paper reviews the main chemical constituents and pharmacological effects of Korla fragrant pears,aiming to provide references for the research and utilization of the deep processing of Korla fragrant pears.
文摘In order to enhance the guidance for Yuluxiang pear cultivation in hilly and mountainous regions, this study provides a comprehensive introduction to various aspects, including the establishment of high-standard orchards and the reinforcement of integrated management techniques, in order to offer a valuable reference for fruit farmers engaged in scientific planting practices.
基金supported by the China Agriculture Research System(CARS-28-14)the National Natural Science Foundation of China(32302484)the University Natural Science Research Project of Anhui Province,China(2022AHO50926 and 2022AH040129).
文摘Pear anthracnose,caused by Colletotrichum fructicola,is a devastating disease that seriously affects most pear varieties,compromising their yield and quality.However,effective control of this pathogen is lacking.Moreover,the critical resistance responses to C.fructicola in pear are unknown.To investigate these resistance mechanisms of pear against C.fructicola,transcriptomic and metabolomic analyses were performed on the anthracnose-resistant variety‘Seli’and susceptible variety‘Cuiguan’after C.fructicola infection.Differentially expressed genes(DEGs)and differentially accumulated metabolites(DAMs)were mainly involved in metabolism and secondary metabolite synthetic pathways,includingα-linoleic acid metabolism,phenylalanine biosynthesis metabolism,unsaturated fatty acids biosynthesis,and biosynthesis of amino acids and their derivatives.In particular,the accumulation of unsaturated fatty acids(UFAs),amino acids,and their derivatives,such as linoleic acid and its derivatives,lauric acid,N-acetyl-L-glutamic acid,and L-proline,was significantly increased in‘Seli’after infection,while the amino acids of oxiglutatione and N-acetyl-L-glutamic acid,as well as the proanthocyanidins,were significantly decreased in‘Cuiguan’.These findings suggest that these metabolites may contribute to the differential anthracnose resistance between‘Seli’and‘Cuiguan’.Overall,our results provid new insights into the regulation of pear anthracnose resistance,which may assist in developing new control strategies and breeding anthracnose-resistant varieties.
基金funded by the Earmarked Fund for CARS(CARS-28-07)the Agricultural Variety Improvement Project of Shandong Province,China(2022LZGC011)the Qingdao Agricultural University Doctoral Start-Up Fund,China.
文摘Dehydrin(DHN)enhances plant resistance to environmental stress by regulating the synthesis of osmotic adjustment substances and scavenging reactive oxygen species.However,the role of PbDHN3 under salt stress remains unclear.In this study,salt stress induced high expression of PbDHN3,and the overexpression of PbDHN3(OE-PbDHN3)enhanced plant growth under salt stress compared to wild-type(WT)plants.OE-PbDHN3 plants exhibited higher chlorophyll content and root growth capacity than WT plants under salt stress.Transcriptome analysis revealed that PbDHN3 expression is associated with ethylene signaling pathways.OE-PbDHN3 transgenic plants substantially influenced ethylene content and the expression of related genes.Following treatment with exogenous ethephon,the transgenic lines notably inhibited the processes of ethylene synthesis and signaling transduction.OE-PbDHN3 transgenic lines treated with exogenous ethylene and the ethylene inhibitor 1-MCP demonstrated significant inhibition of ethylene synthesis and signaling transduction,while promoting root development and chlorophyll content.Under salt stress,OE-PbDHN3 downregulated the expression of ethylene biosynthesis genes PbACO1-like and PbACO2,and signal transduction genes PbEIN3-like during the initial stress phase.This early regulation mitigated the adverse effects of salt stress on the plants.These findings demonstrate that PbDHN3 ameliorates the ethylene-mediated plant growth phenotype under salt stress through regulation of ethylene synthesis and signal transduction.
文摘Significant variations in global temperatures and weather patterns over time are known as climate change.Although it occurs naturally,human activities—particularly the burning of fossil fuels,deforestation,and industrial processes—are accelerating these changes,which have various detrimental effects on the environment.This review aims to highlight the edapho-climatic requirements of this cactus and the advantages and challenges of its cultivation to mitigate climate change.The prickly pear cactus is a plant with numerous financial and environmental advantages.It needs well-draining,sandy or gravelly soil to avoid root rot and do best in full sun.With a strong tolerance for dryness,they thrive in arid or semi-arid regions with scorching summers and prefer sparing watering.Despite being suited to tropical climates,some species can tolerate freezing temperatures and sporadic frost.Once established,these hardy plants require little care and thrive in nutrient-poor soils,which makes them perfect for xeriscaping or challenging growing environments.Because of its high water use efficiency ratio and low water requirements,prickly pear can be grown in marginally dry and semi-arid areas.The cactus does contribute to the ecological and socioeconomic fight against climate change.For instance,it supports sustainable agriculture,biodiversity preservation,soil restoration,carbon sequestration,and effective water usage.Demarcating dry and semi-arid zones and fostering employment in these areas is beneficial from a socioeconomic standpoint.The prickly pear’s traditional cultural heritage supports its current economic function as a crop that can withstand drought.While ecological threats necessitate balanced management,this adaptability promotes sustainable growth.Innovations in bioenergy and value-added goods build on its historical applications,increasing its socioeconomic advantages and,eventually,its worldwide significance.
基金supported by the National Natural Science Foundation of China(32072545 and 32272678)the Young Elite Scientists Sponsorship Program by CAST(2023QNRC001)the Zhejiang Provincial Natural Science Foundation of China(LY22C150003)。
文摘PpMYB10 and PpMYB114 have been identified as the key R2R3-MYB transcription factors(TFs)that positively regulate anthocyanin biosynthesis in pear.Our previous study demonstrated that the ethylene-induced Pp ERF9-Pp TPL1 co-repressor complex represses the expression of PpMYB114,but not PpMYB10,via histone deacetylation.However,the precise molecular mechanism underlying the ethylene-mediated inhibition of PpMYB10 expression remains to be elucidated.The results of this study reveal a high correlation between the expression patterns of PpMYB114 and PpMYB10 in response to ethylene signaling.Moreover,PpMYB114 was found to promote the expression of PpMYB10 by directly binding to the MYB-binding site(MBS)element within its promoter region.Transient overexpression or silencing of PpMYB114 resulted in the promotion or inhibition of PpMYB10 expression in mature pear fruit,respectively.The overexpression of PpMYB114 in pear calli significantly induced PpMYB10 expression and anthocyanin biosynthesis.Conversely,transient silencing of PpMYB10 in PpMYB114-OE pear calli hindered the promotive effect of PpMYB114 on anthocyanin biosynthesis,indicating that PpMYB114 induces anthocyanin biosynthesis,which is at least partially dependent on the transcriptional activation of PpMYB10.Collectively,these results indicate that ethylene may inhibit the expression of PpMYB10 by repressing PpMYB114.Our findings provide insights into a possible mechanism involving ethylene-inhibited PpMYB10 in pear and reveal the regulatory relationship between the R2R3-MYBs involved in anthocyanin biosynthesis.
基金Supported by The Fourth Batch of High-end Talent Project in Hebei ProvinceQuality Evaluation System Project of High-quality Fruits and Vegetables in Hebei Province.
文摘The fruit of Huangguan pear is deeply loved by consumers because of its rich nutrition and rich flavor.The quality evaluation system of Huangguan pear is composed of many quality types.In this study,the types and functions of nutritional quality indexes of Huangguan pear were summarized,such as vitamin C,soluble solids,soluble sugar and titratable acid,and the factors affecting the nutritional quality of Huangguan pear including genetic factors,environmental factors and agricultural management measures were overviewed,aiming to provide reference for establishing a comprehensive quality evaluation system of Huangguan pear and then promoting the high-quality development of Huangguan pear industry.
基金funded by the National Science Foundation of China(32230097)the Earmarked Fund for China Agriculture Research System(CARS-28)the Project of Zhongshan Biological Breeding Laboratory(Grant No.ZSBBL-KY2023-08).
文摘Pear fruit corking disorder is a non-infectious physiological condition that primarily occurs during the late developmental stages of pear and significantly impacts fruit quality and economic value in several major cultivars.As the underlying mechanism remains unclear,effective prevention strategies and genetic improvements continue to present major challenges.In this study,‘Akizuki’pear was used as experimental material,and the lignin content in cork-affected tissue was found to be significantly higher than in healthy tissue.Exogenous abscisic acid(ABA)treatment induced cork formation and promoted lignin biosynthesis,a major structural component,in both pear fruits and calli.Through integrated RNA-seq and expression analyses,we identified the ABA-responsive gene PbrMYB8,which was differentially expressed between healthy and diseased tissues and associated with lignin biosynthesis during corking disorder.Stable transformation of PbrMYB8 into pear calli and Arabidopsis confirmed its role in promoting lignin biosynthesis.Notably,PbrMYB8 not only activated lignin biosynthesis genes independently but also interacted with PbrMYB169 to form a protein complex that co-regulated their expression.These findings improve our understanding of lignin biosynthesis in pear fruit corking disorder by identifying a key regulator and its interaction network and provide a theoretical foundation for future strategies aimed at improving pear fruit quality.
基金supported by the Zhejiang Provincial Natural Science Foundation of China(LR22C150001 to SB,LY22C150003 to JN)the Specialized Research Fund for Major Science and Technique of Zhejiang Province of China(2021C02066-5)+1 种基金the National Natural Science Foundation of China(32072545 to YT,32272639 to SB)the China Agriculture Research System of MOF and MARA(CARS-28)and the Yunnan Science and Technology Talent and Platform Program(202205AF150041)。
文摘Genetic variation contributes to the phenotypic diversity of plants.Most red pear cultivars that accumulate anthocyanins originated from somatic variation and are termed as bud sports.‘Hongzaosu’is a bud sport derived from the green pear‘Zaosu’.A new genetic map was constructed from a population derived from the cross of‘Yuluxiang’and‘Hongzaosu’,from which PpBBX24 was identified as a crucial gene controlling anthocyanin accumulation.Genetic and phylogenetic evidences revealed that PpBBX24 is a repressor of anthocyanin biosynthesis in pear.A 14 bp deletion was detected in the third exon of PpBBX24 in‘Hongzaosu’,resulting in premature termination of protein translation.The truncated PpBBX24 protein was a positive regulator of anthocyanin biosynthesis by activating the transcription of PpCHS and PpUFGT.Three independent variations in the BBX24 coding region that led to premature termination of translation were detected in other pear bud sports and the progeny of a bud sport that all accumulate anthocyanins.The genome of‘Hongzaosu’was assembled using both long-read and short-read sequences.By combining genomic and transcriptomic data,allele-specific expression of PpMYB110a was observed in the fruit skin of‘Hongzaosu',which was likely caused by a large variation in the promoter.This work enhances understanding of coloration in red pears and provides a novel genomic resource for further studies on‘Hongzaosu’pear.
基金Supported by the Earmarked Fund for China Agriculture Research System(CARS-2917)Hubei Innovation Center of Agricultural Science and Technology(2011-620-005003)
文摘Pear is a popular and commercially important fresh fruit, and its texture is related to the presence of sclereid formatted by parenchyma cell with lignification in vascular plants. Previous studies have demonstrated that content of lignin may be regulated by cinnamoyl CoA reductase(CCR) in various plants. However, the function of CCR in pears remains very limited. In the present study, we isolated a cDNA encoding CCR(PpCCR, GenBank accession No. KF999958) and its promoter(proPpCCR) from Whangkeumbae pear to investigate the function of CCR in lignin biosynthesis. PpCCR-GFP expressed in rice mesophyll protoplast demonstrated that PpCCR-GFP was localized in the cytoplasm, indicating that CCR may function in cytoplasm without localization signals. In transgenic plants carrying PpCCR, we observed higher lignin content compared with that in wild type plants, further suggesting that PpCCR can affect the lignin contents through regulating lignin biosynthesis in Arabidopsis thaliana. More studies in other plants are needed to confirm our conclusion.
基金supported in part by Natural Science Foundation of JiangxiAgricultural University, China (1878).
文摘The identification of self-incompatibility genotype （S-genotype） will be useful for selection of pollinizers and design of crossing in cultivar improvement of sand pear. This paper reported the identification of self-incompatibility genotypes of seven Chinese and two Japanese sand pear cultivars using PCR-RFLP analysis and S-RNase sequencing. The Sgenotypes of these cultivars were determined as follows： Huali 1 S1S3, Shounan S1S3, Xizilti S1S4, Qingxiang S3S7, Sanhua S2S7, Huangmi （Imamuranatsu） S1S6, Huali 2 S3S4, Baozhuli S7S33, Cangxixueli S5S15. S-RNase alleles （S1 to S9） in sand pear could be identified effectively by PCR-RFLP analysis.
基金supported by the China Agriculture Research System of MOF and MARA(CARS-29-01)the Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences(CAAS-ASTIP2016-RIP-01)。
文摘Germplasm resources are an important basis for genetic breeding and analysis of complex traits,and research on genetic diversity is conducive to the exploration and creation of new types of germplasm.In this study,the distribution frequency,coefficient of variation,Shannon-Wiener index,and variance and cluster analyses were used to analyze the diversity and trait differences of 39 fruit phenotypic traits from 570 pear accessions,which included 456 pear accessions from 11 species and 114 interspecific hybrid cultivars that had been stored in the National Germplasm Repository of Apple and Pear(Xingcheng,China).The comprehensive evaluation indices were screened by correlation,principal component and regression analyses.A total of 132 variant types were detected in 28 categorical traits of pear germplasm fruit,which indicate a rich diversity.The diversity indices in decreasing order were:fruit shape(1.949),attitude of calyx(1.908),flesh texture type(1.700),persistency of calyx(1.681),russet location(1.658),relief of area around eye basin(1.644),flavor(1.610)and ground color(1.592).The coefficient of variation of titratable acidity in the 11 numerical traits of pear germplasm fruit was as high as 128.43%,which could more effectively reflect the differences between pear accessions.The phenotypic differentiation coefficient V_(st)(66.4%)among the five cultivated pear species,including Pyrus bretschneideri(White Pear),P.pyrifolia(Sand Pear),P.ussuriensis(Ussurian Pear),P.sinkiangensis(Xinjiang Pear),and P.communis(European Pear),was higher than the within population phenotypic differentiation coefficient V_(st)(33.6%).The variation among populations was the main source of variation in pear fruit traits.A hierarchical cluster analysis divided the 389 accessions of six cultivated pear species,including P.pashia(Himalayan Pear),into six categories.There were certain characteristics within the populations,and the differences between populations were not completely clustered by region.For example,Sand Pear cultivars from Japan and the Korean Peninsula clustered together with those from China.Most of the White Pear cultivars clustered with the Sand Pear,and a few clustered with the Ussurian Pear cultivars.The Ussurian Pear and European Pear cultivars clustered separately.The Xinjiang Pear and Himalayan Pear did not cluster together,and neither did the cultivars.Seventeen traits,three describing fruit weight and edible rate(fruit diameter,fruit length and fruit core size),five describing outer quality and morphological characteristics(over color,amount of russeting,dot obviousness,fruit shape,and stalk length),and nine describing inner quality(flesh color,juiciness of flesh,aroma,flavor,flesh texture,flesh texture type,soluble solid contents,titratable acidity,and eating quality)were selected from the 39 traits by principal component and stepwise regression analyses.These 17 traits could reflect 99.3%of the total variation and can be used as a comprehensive evaluation index for pear germplasm resources.
