As a prerequisite for sexual reproduction,gametophyte development is an interesting process involving cell proliferation,differentiation and specialization.Gametogenesis has been extensively explored in model plants,b...As a prerequisite for sexual reproduction,gametophyte development is an interesting process involving cell proliferation,differentiation and specialization.Gametogenesis has been extensively explored in model plants,but the regulatory mechanism of gametophyte development largely remains unknown in Cucurbitaceae species.In present study,we have shown that watermelon ClBBM and ClPLT2,two AP2/ERF transcription factors,participated in both male and female gametophyte development.Clbbm and Clplt2 single mutants resembled wild-type phenotypes in both vegetative and reproductive development.But Clbbm/Clplt2 double mutant showed partial pollen abortion and bore less seeds comparing to WT.Our results indicated that the abnormal pollen grains were caused by premature tapetum degeneration,and reduced seed-set was due to faulty embryo sac development.ClBBM and ClPLT2 were expressed in FG4 embryo sacs,and their transcripts were also detectable in the tapetum and microspore of stage 9 anthers,which was consistent with developmental stages of defective phenotypes observed in double mutant.The expression of genes essential for tapetum development,ClATM1,ClAMS,ClMS1 and ClMS188,was decreased in Clbbm/Clplt2 double mutants.Moreover,the transcriptome analysis indicated that ClBBM and ClPLT2 participated in tapetum and pollen wall development by regulate cell cycle,transmembrane transport,glucan and cellulose metabolic process.Collectively,ClBBM and ClPLT2 were functionally redundant in regulating gametophyte development in watermelon,and their functions differ from their homologous genes in model plant Arabidopsis.展开更多
Watermelon(Citrullus lanatus)is an economically important horticultural crop.However,it is susceptible to lowtemperature stress,which significantly challenges its production and supply.Despite the great economic impor...Watermelon(Citrullus lanatus)is an economically important horticultural crop.However,it is susceptible to lowtemperature stress,which significantly challenges its production and supply.Despite the great economic importance of watermelon,little is known about its response to low-temperature stress at the transcriptional level.In this study,we performed a time-course transcriptome analysis to systematically investigate the regulatory network of watermelon under low-temperature stress.Six low-temperature-responsive gene clusters representing six expression patterns were identified,revealing diverse regulation of metabolic pathways in watermelon under lowtemperature stress.Analysis of temporally specific differentially expressed genes revealed the time-dependent nature of the watermelon response to low temperature.Moreover,ClMYB14 was found to be a negative regulator of low-temperature tolerance as ClMYB14-OE lines were more susceptible to low-temperature stress.Co-expression network analysis demonstrated that ClMYB14 participates in the low-temperature response by regulating the unsaturated fatty acid pathway and heat shock transcription factor.This study provides substantial information for understanding the regulatory network of watermelon in response to low-temperature stress,and identifies candidate genes for the genetic improvement of watermelon with higher low-temperature tolerance.展开更多
The color and pattern of watermelon rind are crucial external traits that directly affect consumer preferences.Watermelons with stripes having a stronger color than the background rind are ideal for studying stripe pa...The color and pattern of watermelon rind are crucial external traits that directly affect consumer preferences.Watermelons with stripes having a stronger color than the background rind are ideal for studying stripe patterns in plants,while there is still limited knowledge about the genetic mechanisms underlying stripe coloration due to the lack of germplasm resources.In this study,we focused on a watermelon germplasm with colorless stripes,and genetic analysis revealed that the trait is controlled by a single recessive gene.The gene Clsc(Citrullus lanatus stripe coloration),which is responsible for the colorless stripe,was localized into a 147.6 kb region on Chr9 by linkage analysis in a large F2 mapping population.Further analysis revealed that the Cla97C09G175170 gene encodes the APRR2 transcription factor,plays a crucial role in determining the watermelon colorless stripe phenotype and was deduced to be related to chlorophyll synthesis and chloroplast development.Physiological experiments indicated that Cla97C09G175170 may significantly influence chloroplast development and chlorophyll synthesis in watermelon.The results of this study provide a better understanding of the molecular mechanism of stripe coloration in watermelon and can be useful in the development of marker-assisted selection(MAS)for new watermelon cultivars.展开更多
Watermelon(Citrullus lanatus),one of the top five fruit crops based on the gross tonnage and cultivated area globally,holds major economic importance in agriculture and contributes substantially to farmers’incomes.Wa...Watermelon(Citrullus lanatus),one of the top five fruit crops based on the gross tonnage and cultivated area globally,holds major economic importance in agriculture and contributes substantially to farmers’incomes.Watermelon cultivation relies on sexual reproduction,with meiosis playing a pivotal role in this process.However,our understanding of the meiotic mechanism in watermelon remains limited.In this study,we utilized CRISPR/Cas9 technology to target ClDYAD,a homolog of the meiosis-related genes AtDYAD and OsAM1,and conducted functional analysis to explore the initiation of meiosis in watermelon.ClDYAD was highly expressed in tender male flowers both before and during the early stages of meiosis.Mutations in ClDYAD led to meiotic arrest at the leptotene stage,impeding the normal enlargement of microspore mother cells and megasporocytes.This resulted in the absence of pollen in anthers and seed abortion.ClDYAD physically interacts with the protein encoded by Cla97C07G137480,which was identified as a switch-associated protein 70-like protein(ClSWAP-70).The expression pattern of ClSWAP-70 in tender male flowers of various sizes matched with the changes in ClDYAD mRNA levels.These findings shed light on the molecular mechanisms governing the initiation of meiosis in watermelon,offering valuable insights into male and female sterility in Cucurbitaceae plants and guiding future research.展开更多
Genotyping by Target Sequencing(GBTS)technology,known for its flexibility,high efficiency,high throughput,and low cost,has been increasingly employed in molecular breeding.However,there is still limited study on the d...Genotyping by Target Sequencing(GBTS)technology,known for its flexibility,high efficiency,high throughput,and low cost,has been increasingly employed in molecular breeding.However,there is still limited study on the design and development of high-throughput genotyping tools in watermelon.In this study,we identified 112000 high quality SNPs by analyzing the resequencing data of 43 cultivated watermelon accessions.11921 and 6094 SNPs were selected for developing two sets of watermelon liquid-phase chips with different marker densities,named Watermelon 10K and 5K,respectively.Furthermore,the SNPs and Indels of most mapped gene/QTLs for many agronomic important traits in watermelon were also integrated into the two chips for foreground selection.These chips have been tested using GBTS technology in various applications in watermelon.The genotyping of 76 accessions by Watermelon 5K liquid-phase chip showed an average detection rate of 99.28%and 81.78%for cultivated and wild watermelon accessions,respectively.This provided enough markers information for GWAS and two significant QTLs,ssc1.1 and ssc1.2,associated with soluble sugar content were detected.Furthermore,BSA-seq analysis for non-lobed leaf and dwarf traits were validated by liquid-phase chips,and the candidate region was consistent with our previous studies.Additionally,we precisely introduced the Cldw1 and Clbl genes into an elite inbred line WT2 using Watermelon 5K for assisted selection,resulting in the development of three new germplasm with good plant architecture.As a high-throughput genotyping liquid-phase SNP array,the Watermelon 10K and 5K chips will greatly facilitate functional studies and molecular breeding in watermelon.展开更多
Watermelon is a highly cultivated fruit crop renowned for its quality properties of fruit flesh.Among various quality factors,fruit flesh firmness is a crucial quality parameter influencing the fruit texture,shelf lif...Watermelon is a highly cultivated fruit crop renowned for its quality properties of fruit flesh.Among various quality factors,fruit flesh firmness is a crucial quality parameter influencing the fruit texture,shelf life and its commercial value.The auxin/indole-3-acetic acid(Aux/IAA)plays a significant role in fruit development and ripening of non-climacteric fruits.However,the regulatory mechanism of Aux/IAA in controlling fruit flesh firmness and ripening in watermelon remains unknown.In this study,we employed an integrative approach combining genome-wide association study(GWAS)and bulked segregant RNA-Seq analysis(BSR-Seq)to identify an overlapping candidate region between 12776310 and 12968331 bp on chromosome 6,underlying an auxin-responsive gene(Aux/IAA)associated with flesh firmness in watermelon.Transcriptome analysis,followed by real-time quantitative reverse transcription PCR(qRT-PCR),confirmed that the expression of Aux/IAA was consistently higher in fruits with high flesh firmness.The sequence alignment revealed a single base mutation in the coding region of Aux/IAA.Furthermore,the concomitant Kompetitive/Competitive allele-specific PCR(KASP)genotyping data sets for F2 population and germplasm accessions identified Aux/IAA as a strong candidate gene associated with flesh firmness.Aux/IAA was enriched in the plant hormone signal transduction pathway,involving cell enlargement and leading to low flesh firmness.We determined the higher accumulation of abscisic acid(ABA)in fruits with low flesh firmness than hard flesh.Moreover,overexpression of Aux/IAA induced higher flesh firmness with an increased number of fruit flesh cells while reducing ABA content and flesh cell sizes.Additionally,the allelic variation in Aux/IAA for soft flesh firmness was found to exist in Citrullus mucosospermus and gradually fixed into Citrullus lanatus during domestication,indicating that soft flesh firmness was a domesticated trait.These findings significantly enhanced our understanding of watermelon fruit flesh firmness and consequently the watermelon fruit quality.展开更多
Watermelon(Citrullus lanatus)holds global significance as a fruit with high economic and nutritional value.Exploring the regulatory network of watermelon male reproductive development is crucial for developing male st...Watermelon(Citrullus lanatus)holds global significance as a fruit with high economic and nutritional value.Exploring the regulatory network of watermelon male reproductive development is crucial for developing male sterile materials and facilitating cross-breeding.Despite its importance,there is a lack of research on the regulation mechanism of male reproductive development in watermelon.In this study,we identified that ClESR2,a VIIIb subclass member in the APETALA2/Ethylene Responsive Factor(AP2/ERF)superfamily,was a key factor in pollen development.RNA insitu hybridization confirmed significantClESR2 expression in the tapetum and pollen during the later stage of anther development.The pollens of transgenic plants showed major defects in morphology and vitality at the late development stage.The RNA-seq and protein interaction assay confirmed that ClESR2 regulates pollen morphology and fertility by interacting with key genes involved in pollen development at both transcriptional and protein levels.These suggest that Enhancer of Shoot Regeneration 2(ESR2)plays an important role in pollen maturation and vitality.This study helps understand the male reproductive development of watermelon,providing a theoretical foundation for developing male sterile materials.展开更多
Root regeneration is an important factor influencing the healing rate of graft union and the survival of double-root-cutting grafting.To date,little information is available on how to enhance root regeneration of root...Root regeneration is an important factor influencing the healing rate of graft union and the survival of double-root-cutting grafting.To date,little information is available on how to enhance root regeneration of rootstock in grafted watermelon(Citrullus lanatus)seedlings.In this study,the effects of different light treatments on root regeneration were determined.This revealed that addition of far-red light(Fr)could significantly expedite root formation in the rootstock.Moreover,the results of transcriptome analysis revealed that plant hormone pathway and auxinrelated genes were greatly induced by Fr,especially for auxin-response proteins(including CmIAA11,CmIAA17,and CmAUX28),Small auxinup RNA genes(including CmSAUR20 and CmSAUR50)and the auxin efflux transporter(CmPIN3).In addition,the expression of Phytochrome Interacting Factor(PIFs),such as CmPIF1,CmPIF3 and CmPIF7,was remarkably increased by Fr.These genes may act together to activate auxinrelated pathways under Fr treatment.Based on the results of HPLC-MS/MS analysis,the concentrations of different auxin-types in adventitious root were significantly influenced by Fr.Furthermore,the better growth of rootstock root displayed superior vasculature transport activity of the graft union with Fr treatment,which was determined by the acid magenta dyeing experiment.Therefore,all the results suggested that Fr could induce AR formation in rootstocks,which may be associated with the auxin accumulation by regulating the transcriptional level of auxinrelated and PIF genes.The findings of this study demonstrated a practicable way to shorten the healing period of graftings and improve the quality of grafted watermelon seedlings,which will provide a theoretical basis for the speeding development of industrialized seedlings production.展开更多
Stigma color is a critical agronomic trait in watermelon that plays an important role in pollination.However,there are few reports on the regulation of stigma color in watermelon.In this study,a genetic analysis of th...Stigma color is a critical agronomic trait in watermelon that plays an important role in pollination.However,there are few reports on the regulation of stigma color in watermelon.In this study,a genetic analysis of the F2 population derived from ZXG1553(P1,with orange stigma)and W1-17(P2,with yellow stigma)indicated that stigma color is a quantitative trait and the orange stigma is recessive compared with the yellow stigma.Bulk segregant analysis sequencing(BSA-seq)revealed a 3.75 Mb segment on chromosome 6 that is related to stigma color.Also,a major stable effective QTL Clqsc6.1(QTL stigma color)was detected in two years between cleaved amplified polymorphic sequencing(CAPS)markers Chr06_8338913 and Chr06_9344593 spanning a~1.01 Mb interval that harbors 51 annotated genes.Cla97C06G117020(annotated as zinc finger protein CONSTANS-LIKE 4)was identified as the best candidate gene for the stigma color trait through RNA-seq,quantitative real-time PCR(qRT-PCR),and gene structure alignment analysis among the natural watermelon panel.The expression level of Cla97C06G117020 in the orange stigma accession was lower than in the yellow stigma accessions with a significant difference.A nonsynonymous SNP site of the Cla97C06G117020 coding region that causes amino acid variation was related to the stigma color variation among nine watermelon accessions according to their re-sequencing data.Stigma color formation is often related to carotenoids,and we also found that the expression trend of ClCHYB(annotated asβ-carotene hydroxylase)in the carotenoid metabolic pathway was consistent with Cla97C06G117020,and it was expressed in low amounts in the orange stigma accession.These data indicated that Cla97C06G117020 and ClCHYB may interact to form the stigma color.This study provides a theoretical basis for gene fine mapping and mechanisms for the regulation of stigma color in watermelon.展开更多
[Objectives]This study was conducted to explore suitable organic compound application models for watermelon growth.[Methods]With watermelon hybrid material"M22×P18"as the test material,the effects of fo...[Objectives]This study was conducted to explore suitable organic compound application models for watermelon growth.[Methods]With watermelon hybrid material"M22×P18"as the test material,the effects of four functional organic materials,namely garlic straw treatment(T_(1)),onion straw treatment(T_(2)),garlic straw+sheep manure treatment(T_(3))and onion straw+chicken manure treatment(T_(4)),on the morphological indexes,yield and quality of watermelon were investigated.[Results]Different functional organic materials had different effects on morphological indexes,yield and quality of watermelon.The morphological indexes,nutritional quality indexes and yield of watermelon treated with garlic straw and sheep manure compound(T_(3))and onion straw and chicken manure compound(T_(4))were significantly higher than those treated simply with garlic straw(T_(1))and onion straw(T_(2)),and T_(3)performed relatively better.Compared with treatment T_(2),T_(3)showed a stem diameter,vine length and leaf number increasing by 43.05%,46.69%and 40.77%respectively,central sugar and side sugar contents increasing by 11.72%and 21.90%respectively,and a yield increasing by 42.91%,with significant differences from T_(2).[Conclusions]This study provides technical support for high-quality and high-yielding cultivation of watermelon.展开更多
[Objectives]This study was conducted to explore a functional organic material formula suitable for watermelon cultivation with high quality,high yield and high efficiency.[Methods]Four treatments were set in the exper...[Objectives]This study was conducted to explore a functional organic material formula suitable for watermelon cultivation with high quality,high yield and high efficiency.[Methods]Four treatments were set in the experiment,namely four functional organic materials,garlic straw treatment(T_(1)),onion straw treatment(T_(2)),garlic straw+sheep manure treatment(T_(3))and onion straw+chicken manure treatment(T_(4)),to investigate the effects of different functional organic materials on fresh weight,quality,single-melon weight and SPAD value of watermelon.[Results]The effects of different functional organic materials on fresh weight,quality,single-melon weight and SPAD value of watermelon were quite different.The fresh weight,quality,single-melon weight and SPAD value of watermelon were higher in treatment T_(3)applying garlic straw and sheep manure and treatment T_(4)applying onion straw and chicken manure than in treatment T_(1)applying garlic straw and treatment T_(2)applying onion straw.Specifically,the fresh weight of whole plant was the highest in treatment T_(3),followed by treatment T_(4),and the values of the two treatments increased by 12.83%and 5.94%respectively compared with treatment T_(1);the weight of single melon was the highest in treatment T_(3),followed by treatment T_(4),and the values of the two treatments increased by 42.45%and 31.77%respectively compared with treatment T_(2);and the SPAD values of treatments T_(3)and T_(4)were significantly higher than those of treatments T_(1)and T_(2),and the value of treatment T_(3)was the largest.[Conclusions]This study provides theoretical support for the popularization and application of fertilization techniques combining organic fertilizers and reduced chemical fertilizers for watermelon.展开更多
基金supported by the National Youth Talent Program(Grant No.A279021801)Key-Area R&D Program of Guangdong Province(Grant No.2022B0202060001)+3 种基金Science and Technology Innovation Team of Shaanxi(Grant No.2021TD-32)the Natural Science Foundation of Shaanxi Province(Grant Nos.2021JM-089,2022JM112 and 2022JQ-162)the Key R&D Project from Yangling Seed Industry Innovation Center(Grant No.K3031322016)Fundamental Research Funds for the Central Universities(Grant No.2452022111)。
文摘As a prerequisite for sexual reproduction,gametophyte development is an interesting process involving cell proliferation,differentiation and specialization.Gametogenesis has been extensively explored in model plants,but the regulatory mechanism of gametophyte development largely remains unknown in Cucurbitaceae species.In present study,we have shown that watermelon ClBBM and ClPLT2,two AP2/ERF transcription factors,participated in both male and female gametophyte development.Clbbm and Clplt2 single mutants resembled wild-type phenotypes in both vegetative and reproductive development.But Clbbm/Clplt2 double mutant showed partial pollen abortion and bore less seeds comparing to WT.Our results indicated that the abnormal pollen grains were caused by premature tapetum degeneration,and reduced seed-set was due to faulty embryo sac development.ClBBM and ClPLT2 were expressed in FG4 embryo sacs,and their transcripts were also detectable in the tapetum and microspore of stage 9 anthers,which was consistent with developmental stages of defective phenotypes observed in double mutant.The expression of genes essential for tapetum development,ClATM1,ClAMS,ClMS1 and ClMS188,was decreased in Clbbm/Clplt2 double mutants.Moreover,the transcriptome analysis indicated that ClBBM and ClPLT2 participated in tapetum and pollen wall development by regulate cell cycle,transmembrane transport,glucan and cellulose metabolic process.Collectively,ClBBM and ClPLT2 were functionally redundant in regulating gametophyte development in watermelon,and their functions differ from their homologous genes in model plant Arabidopsis.
基金financed by the National Natural Science Foundation of China(31471894)the China Agriculture Research System of MOF and MARA(CARS-25)the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences(CAASASTIP-ZFRI)。
文摘Watermelon(Citrullus lanatus)is an economically important horticultural crop.However,it is susceptible to lowtemperature stress,which significantly challenges its production and supply.Despite the great economic importance of watermelon,little is known about its response to low-temperature stress at the transcriptional level.In this study,we performed a time-course transcriptome analysis to systematically investigate the regulatory network of watermelon under low-temperature stress.Six low-temperature-responsive gene clusters representing six expression patterns were identified,revealing diverse regulation of metabolic pathways in watermelon under lowtemperature stress.Analysis of temporally specific differentially expressed genes revealed the time-dependent nature of the watermelon response to low temperature.Moreover,ClMYB14 was found to be a negative regulator of low-temperature tolerance as ClMYB14-OE lines were more susceptible to low-temperature stress.Co-expression network analysis demonstrated that ClMYB14 participates in the low-temperature response by regulating the unsaturated fatty acid pathway and heat shock transcription factor.This study provides substantial information for understanding the regulatory network of watermelon in response to low-temperature stress,and identifies candidate genes for the genetic improvement of watermelon with higher low-temperature tolerance.
基金supported by grants from theKey Scientific and Technological Project of Henan Province,China(222102110124)the Joint Fund of Science and Technology Research and Development Plan,Henan Province,China(222103810009)+4 种基金the National Natural Science Foundation of China(32172574,3217180560)the Funding of Joint Research on Agricultural Varieties Improvement of Henan Province,China(2022010503)the Major Science and Technology Project of Henan Province,China(221100110400)the Natural Science Foundation of Henan,China(222300420050)the Science and Technology Innovation Talent Support Program of Henan Province,China(23HASTIT034).
文摘The color and pattern of watermelon rind are crucial external traits that directly affect consumer preferences.Watermelons with stripes having a stronger color than the background rind are ideal for studying stripe patterns in plants,while there is still limited knowledge about the genetic mechanisms underlying stripe coloration due to the lack of germplasm resources.In this study,we focused on a watermelon germplasm with colorless stripes,and genetic analysis revealed that the trait is controlled by a single recessive gene.The gene Clsc(Citrullus lanatus stripe coloration),which is responsible for the colorless stripe,was localized into a 147.6 kb region on Chr9 by linkage analysis in a large F2 mapping population.Further analysis revealed that the Cla97C09G175170 gene encodes the APRR2 transcription factor,plays a crucial role in determining the watermelon colorless stripe phenotype and was deduced to be related to chlorophyll synthesis and chloroplast development.Physiological experiments indicated that Cla97C09G175170 may significantly influence chloroplast development and chlorophyll synthesis in watermelon.The results of this study provide a better understanding of the molecular mechanism of stripe coloration in watermelon and can be useful in the development of marker-assisted selection(MAS)for new watermelon cultivars.
基金supported by Shaanxi Provincial Central Leading Local Science and Technology Development Special Fund(Grant No.2023ZY-QYCX-02)the National Youth Talent Program(Grant No.A279021801)+3 种基金Earmarked Fund for China Agriculture Research System(Grant No.CARS-25)Key R&D Program of Shaanxi Province(Grant Nos.2023-YBNY-008 and 2024NC-YBXM-032)the Fundamental Research Funds for the Central Universities(Grant Nos.10120221103 and 2452022111)the Science and Technology Innovation Team of Shaanxi(Grant No.2021TD-32).
文摘Watermelon(Citrullus lanatus),one of the top five fruit crops based on the gross tonnage and cultivated area globally,holds major economic importance in agriculture and contributes substantially to farmers’incomes.Watermelon cultivation relies on sexual reproduction,with meiosis playing a pivotal role in this process.However,our understanding of the meiotic mechanism in watermelon remains limited.In this study,we utilized CRISPR/Cas9 technology to target ClDYAD,a homolog of the meiosis-related genes AtDYAD and OsAM1,and conducted functional analysis to explore the initiation of meiosis in watermelon.ClDYAD was highly expressed in tender male flowers both before and during the early stages of meiosis.Mutations in ClDYAD led to meiotic arrest at the leptotene stage,impeding the normal enlargement of microspore mother cells and megasporocytes.This resulted in the absence of pollen in anthers and seed abortion.ClDYAD physically interacts with the protein encoded by Cla97C07G137480,which was identified as a switch-associated protein 70-like protein(ClSWAP-70).The expression pattern of ClSWAP-70 in tender male flowers of various sizes matched with the changes in ClDYAD mRNA levels.These findings shed light on the molecular mechanisms governing the initiation of meiosis in watermelon,offering valuable insights into male and female sterility in Cucurbitaceae plants and guiding future research.
基金supported by the National Natural Science Foundation of China(Grant Nos.32172602,32472739)the Major Science and Technology Project of Henan Province(Grant No.221100110400)+3 种基金the Funding of Joint Research on Agricultural Varietie Improvement of Henan Province(Grant No.2022010503)the Natural Science Foundation of Henan(Grant No.242300421030)the Key Scientifc and Technological Project of Henan Province(Grant Nos.242102111124,242102111115)the Key Research and Development Program of Xinjiang Uygur autonomous region(2023B02017-2).
文摘Genotyping by Target Sequencing(GBTS)technology,known for its flexibility,high efficiency,high throughput,and low cost,has been increasingly employed in molecular breeding.However,there is still limited study on the design and development of high-throughput genotyping tools in watermelon.In this study,we identified 112000 high quality SNPs by analyzing the resequencing data of 43 cultivated watermelon accessions.11921 and 6094 SNPs were selected for developing two sets of watermelon liquid-phase chips with different marker densities,named Watermelon 10K and 5K,respectively.Furthermore,the SNPs and Indels of most mapped gene/QTLs for many agronomic important traits in watermelon were also integrated into the two chips for foreground selection.These chips have been tested using GBTS technology in various applications in watermelon.The genotyping of 76 accessions by Watermelon 5K liquid-phase chip showed an average detection rate of 99.28%and 81.78%for cultivated and wild watermelon accessions,respectively.This provided enough markers information for GWAS and two significant QTLs,ssc1.1 and ssc1.2,associated with soluble sugar content were detected.Furthermore,BSA-seq analysis for non-lobed leaf and dwarf traits were validated by liquid-phase chips,and the candidate region was consistent with our previous studies.Additionally,we precisely introduced the Cldw1 and Clbl genes into an elite inbred line WT2 using Watermelon 5K for assisted selection,resulting in the development of three new germplasm with good plant architecture.As a high-throughput genotyping liquid-phase SNP array,the Watermelon 10K and 5K chips will greatly facilitate functional studies and molecular breeding in watermelon.
基金the Agricultural Science and Technology Innovation Program(Grant No.CAAS-ASTIP-2021-ZFRI)China Agriculture Research System of MOF and MARA(Grant No.CARS-25-03)+3 种基金National Nature Science Foundation of China(Grant Nos.31672178 and 31471893)the Natural Science Foundation of Henan Province(Grant No.212300410312)the scientific and technological research in Henan Province(Grant No.202102110398)the key project of the Action of“Rejuvenating Mongolia with Science and Technology”(Grant No.NMKJXM202114).
文摘Watermelon is a highly cultivated fruit crop renowned for its quality properties of fruit flesh.Among various quality factors,fruit flesh firmness is a crucial quality parameter influencing the fruit texture,shelf life and its commercial value.The auxin/indole-3-acetic acid(Aux/IAA)plays a significant role in fruit development and ripening of non-climacteric fruits.However,the regulatory mechanism of Aux/IAA in controlling fruit flesh firmness and ripening in watermelon remains unknown.In this study,we employed an integrative approach combining genome-wide association study(GWAS)and bulked segregant RNA-Seq analysis(BSR-Seq)to identify an overlapping candidate region between 12776310 and 12968331 bp on chromosome 6,underlying an auxin-responsive gene(Aux/IAA)associated with flesh firmness in watermelon.Transcriptome analysis,followed by real-time quantitative reverse transcription PCR(qRT-PCR),confirmed that the expression of Aux/IAA was consistently higher in fruits with high flesh firmness.The sequence alignment revealed a single base mutation in the coding region of Aux/IAA.Furthermore,the concomitant Kompetitive/Competitive allele-specific PCR(KASP)genotyping data sets for F2 population and germplasm accessions identified Aux/IAA as a strong candidate gene associated with flesh firmness.Aux/IAA was enriched in the plant hormone signal transduction pathway,involving cell enlargement and leading to low flesh firmness.We determined the higher accumulation of abscisic acid(ABA)in fruits with low flesh firmness than hard flesh.Moreover,overexpression of Aux/IAA induced higher flesh firmness with an increased number of fruit flesh cells while reducing ABA content and flesh cell sizes.Additionally,the allelic variation in Aux/IAA for soft flesh firmness was found to exist in Citrullus mucosospermus and gradually fixed into Citrullus lanatus during domestication,indicating that soft flesh firmness was a domesticated trait.These findings significantly enhanced our understanding of watermelon fruit flesh firmness and consequently the watermelon fruit quality.
基金support from the National Key Research and Development Program of China(2022YFD1602000)the National Natural Science Foundation of China(32202514,U22A20498 and 32072596)+2 种基金the Joint Fund of Henan Province Science and Technology Research and Development Plan,China(222103810009)the Science and Technology Innovation Team of Shaanxi,China(2021TD-32)the China Postdoctoral Science Foundation(2022M711064 and 2023M741062).
文摘Watermelon(Citrullus lanatus)holds global significance as a fruit with high economic and nutritional value.Exploring the regulatory network of watermelon male reproductive development is crucial for developing male sterile materials and facilitating cross-breeding.Despite its importance,there is a lack of research on the regulation mechanism of male reproductive development in watermelon.In this study,we identified that ClESR2,a VIIIb subclass member in the APETALA2/Ethylene Responsive Factor(AP2/ERF)superfamily,was a key factor in pollen development.RNA insitu hybridization confirmed significantClESR2 expression in the tapetum and pollen during the later stage of anther development.The pollens of transgenic plants showed major defects in morphology and vitality at the late development stage.The RNA-seq and protein interaction assay confirmed that ClESR2 regulates pollen morphology and fertility by interacting with key genes involved in pollen development at both transcriptional and protein levels.These suggest that Enhancer of Shoot Regeneration 2(ESR2)plays an important role in pollen maturation and vitality.This study helps understand the male reproductive development of watermelon,providing a theoretical foundation for developing male sterile materials.
基金supported by Jiangsu Provincial Basic Research Program(Natural Science Foundation,Grant No.BK20241175)The project of Agriculture Ministry Key Laboratory of Agricultural Engineering in the Middle and Lower Reaches of Yangtze River[Grant No.(23)3104]Jiangsu Agricultural Science and Technology Innovation Fund[Grant No.CX(21)2022]。
文摘Root regeneration is an important factor influencing the healing rate of graft union and the survival of double-root-cutting grafting.To date,little information is available on how to enhance root regeneration of rootstock in grafted watermelon(Citrullus lanatus)seedlings.In this study,the effects of different light treatments on root regeneration were determined.This revealed that addition of far-red light(Fr)could significantly expedite root formation in the rootstock.Moreover,the results of transcriptome analysis revealed that plant hormone pathway and auxinrelated genes were greatly induced by Fr,especially for auxin-response proteins(including CmIAA11,CmIAA17,and CmAUX28),Small auxinup RNA genes(including CmSAUR20 and CmSAUR50)and the auxin efflux transporter(CmPIN3).In addition,the expression of Phytochrome Interacting Factor(PIFs),such as CmPIF1,CmPIF3 and CmPIF7,was remarkably increased by Fr.These genes may act together to activate auxinrelated pathways under Fr treatment.Based on the results of HPLC-MS/MS analysis,the concentrations of different auxin-types in adventitious root were significantly influenced by Fr.Furthermore,the better growth of rootstock root displayed superior vasculature transport activity of the graft union with Fr treatment,which was determined by the acid magenta dyeing experiment.Therefore,all the results suggested that Fr could induce AR formation in rootstocks,which may be associated with the auxin accumulation by regulating the transcriptional level of auxinrelated and PIF genes.The findings of this study demonstrated a practicable way to shorten the healing period of graftings and improve the quality of grafted watermelon seedlings,which will provide a theoretical basis for the speeding development of industrialized seedlings production.
基金supported by fundings from the Natural Science Funds for Outstanding Youth of Heilongjiang Province,China(YQ2022C011)the National Natural Science Foundation of China(32172577)+2 种基金the China Agriculture Research System of MOF and MARA,China(CARS-25)the Taishan Industrial Leading Talents Project,China(LJNY202112)the Natural Science Foundation of Heilongjiang Province,China(LH2022C025).
文摘Stigma color is a critical agronomic trait in watermelon that plays an important role in pollination.However,there are few reports on the regulation of stigma color in watermelon.In this study,a genetic analysis of the F2 population derived from ZXG1553(P1,with orange stigma)and W1-17(P2,with yellow stigma)indicated that stigma color is a quantitative trait and the orange stigma is recessive compared with the yellow stigma.Bulk segregant analysis sequencing(BSA-seq)revealed a 3.75 Mb segment on chromosome 6 that is related to stigma color.Also,a major stable effective QTL Clqsc6.1(QTL stigma color)was detected in two years between cleaved amplified polymorphic sequencing(CAPS)markers Chr06_8338913 and Chr06_9344593 spanning a~1.01 Mb interval that harbors 51 annotated genes.Cla97C06G117020(annotated as zinc finger protein CONSTANS-LIKE 4)was identified as the best candidate gene for the stigma color trait through RNA-seq,quantitative real-time PCR(qRT-PCR),and gene structure alignment analysis among the natural watermelon panel.The expression level of Cla97C06G117020 in the orange stigma accession was lower than in the yellow stigma accessions with a significant difference.A nonsynonymous SNP site of the Cla97C06G117020 coding region that causes amino acid variation was related to the stigma color variation among nine watermelon accessions according to their re-sequencing data.Stigma color formation is often related to carotenoids,and we also found that the expression trend of ClCHYB(annotated asβ-carotene hydroxylase)in the carotenoid metabolic pathway was consistent with Cla97C06G117020,and it was expressed in low amounts in the orange stigma accession.These data indicated that Cla97C06G117020 and ClCHYB may interact to form the stigma color.This study provides a theoretical basis for gene fine mapping and mechanisms for the regulation of stigma color in watermelon.
基金Supported by Shangqiu Science and Technology Research Project(202405).
文摘[Objectives]This study was conducted to explore suitable organic compound application models for watermelon growth.[Methods]With watermelon hybrid material"M22×P18"as the test material,the effects of four functional organic materials,namely garlic straw treatment(T_(1)),onion straw treatment(T_(2)),garlic straw+sheep manure treatment(T_(3))and onion straw+chicken manure treatment(T_(4)),on the morphological indexes,yield and quality of watermelon were investigated.[Results]Different functional organic materials had different effects on morphological indexes,yield and quality of watermelon.The morphological indexes,nutritional quality indexes and yield of watermelon treated with garlic straw and sheep manure compound(T_(3))and onion straw and chicken manure compound(T_(4))were significantly higher than those treated simply with garlic straw(T_(1))and onion straw(T_(2)),and T_(3)performed relatively better.Compared with treatment T_(2),T_(3)showed a stem diameter,vine length and leaf number increasing by 43.05%,46.69%and 40.77%respectively,central sugar and side sugar contents increasing by 11.72%and 21.90%respectively,and a yield increasing by 42.91%,with significant differences from T_(2).[Conclusions]This study provides technical support for high-quality and high-yielding cultivation of watermelon.
基金Supported by Shangqiu Science and Technology Research Project(202405).
文摘[Objectives]This study was conducted to explore a functional organic material formula suitable for watermelon cultivation with high quality,high yield and high efficiency.[Methods]Four treatments were set in the experiment,namely four functional organic materials,garlic straw treatment(T_(1)),onion straw treatment(T_(2)),garlic straw+sheep manure treatment(T_(3))and onion straw+chicken manure treatment(T_(4)),to investigate the effects of different functional organic materials on fresh weight,quality,single-melon weight and SPAD value of watermelon.[Results]The effects of different functional organic materials on fresh weight,quality,single-melon weight and SPAD value of watermelon were quite different.The fresh weight,quality,single-melon weight and SPAD value of watermelon were higher in treatment T_(3)applying garlic straw and sheep manure and treatment T_(4)applying onion straw and chicken manure than in treatment T_(1)applying garlic straw and treatment T_(2)applying onion straw.Specifically,the fresh weight of whole plant was the highest in treatment T_(3),followed by treatment T_(4),and the values of the two treatments increased by 12.83%and 5.94%respectively compared with treatment T_(1);the weight of single melon was the highest in treatment T_(3),followed by treatment T_(4),and the values of the two treatments increased by 42.45%and 31.77%respectively compared with treatment T_(2);and the SPAD values of treatments T_(3)and T_(4)were significantly higher than those of treatments T_(1)and T_(2),and the value of treatment T_(3)was the largest.[Conclusions]This study provides theoretical support for the popularization and application of fertilization techniques combining organic fertilizers and reduced chemical fertilizers for watermelon.
