Protoplasts isolated from cotyledon-derived calli of Actinidia chinensis var. chinensis (2n = 2x=58) were fused by the PEG method with cotyledon-callus protoplasts of A. deliciosa var. deliciosa (2n = 6x = 174) or wit...Protoplasts isolated from cotyledon-derived calli of Actinidia chinensis var. chinensis (2n = 2x=58) were fused by the PEG method with cotyledon-callus protoplasts of A. deliciosa var. deliciosa (2n = 6x = 174) or with mesophyll protoplasts of A. kolomikta (2n = 2x = 58), respectively. Randomly amplified polymorphic DNA (RAPD) markers and flow cytometry was used to confirm the occurrence of somatic hybrids. RAPD results with some primers surveyed indicated that one clone (A. chinensis + A. deliciosa) and four clones (A. chinensis + A. kolomikta) had RAPD banding patterns which combined the parental banding profiles. Ploidy levels of the (A. chinensis + A. deliciosa) clone were deduced as octoploid (2n = 8x), and the (A. chinensis + A. kolomikta) clones were tetraploid (2n = 4x), triploid (2n = 3x) or pentaploid (2n = 5x). The clones were confirmed as interspecific somatic hybrids in Actinidia.展开更多
Pseudomonas syringae pv.actinidiae(Psa)causes destructive kiwifruit bacterial canker by invading vascular tissues across multiple plant organs.However,the cellular mechanism underlying its systemic transmission and ce...Pseudomonas syringae pv.actinidiae(Psa)causes destructive kiwifruit bacterial canker by invading vascular tissues across multiple plant organs.However,the cellular mechanism underlying its systemic transmission and cell-to-cell movement within these specialized vascular conduits remains unclear.In this study,a Psa-GFP strain and various microscopic techniques were used to investigate the interaction between kiwifruit and Psa.Our results reveal that Psa strategically exploits host vascular conduits for systemic movement,with the xylem vessel being the predominant avenue.In the phloem,Psa exhibits adaptive alteration in bacterial shape to traverse sieve pores,facilitating its systemic spread along sieve tubes and inducing phloem necrosis.Within the xylem,Psa breaches pit membranes to migrate between adjacent vessels.Furthermore,phloem fibers act as an initial barrier at the early stages of infection,delaying Psa's entry into vascular tissues during its journey to the xylem.Additionally,at the junctions of stem-stem or stem-leaf,branch trace or leaf trace mediates the bacterial organ-to-organ translocation,thus facilitating the systemic progression of disease.In conclusion,our findings shed light on the cellular mechanism employed by Psa to exploit the woody plant's vascular network for infection,thereby enhancing a better understanding of the biology of this poorly defined bacterium.These insights carry implications for the pathogenesis of Psa and other vascular pathogens,offering theoretical guidance for effective control strategies.展开更多
[Objective] The variation of sugar, acid and AsA contents in fruits of ‘Ganmi 6＇ kiwifruit （Actinidia eriantha Benth） were investigated during fruit develop- ment. [Method] Kiwi fruits were randomly taken as mater...[Objective] The variation of sugar, acid and AsA contents in fruits of ‘Ganmi 6＇ kiwifruit （Actinidia eriantha Benth） were investigated during fruit develop- ment. [Method] Kiwi fruits were randomly taken as materials every 15 days since 20 days after full bloom （DAFB） to 170 DAFB until in mature stage. [Result] The results showed that during fruit development of ‘Ganmi 6＇, the total sugar soluble contents had a rising trend with relatively stable at 95 DAFB, then rose until har- vest with the maximum content （10.35%）. The titratable acid content showed a trend of increasing, then declining, then increase to the harvest content （1.10%）. From the sugar acid ratio, we can knew it decreased in 95 DAFB, then up to the max （9.38）. The changes of AsA contents showed double ‘S＇ shape, decreased af- ter the first increased rapidly, slightly increased and then decreased in the early harvest. [Conclusion] It provided a theoretical basis for scientific cultivation methods to explore the nutrients regulation.展开更多
[Objective] To study the ecophysiological effects of low temperature stress on Actinidia arguta （Seib.et.Zucc.）, and provide a theoretical basis for the introduc- tion and breeding of cold resistant varieties. [Meth...[Objective] To study the ecophysiological effects of low temperature stress on Actinidia arguta （Seib.et.Zucc.）, and provide a theoretical basis for the introduc- tion and breeding of cold resistant varieties. [Method] A. arguta as the test material was processed at room temperature of 4 ℃ to determine the contents of chloro- phyll, water soluble sugar, water soluble protein, free proline, MDA, and antioxidant enzymes （POD activity, SOD activity, CAT activity） with the treatment at 25℃ as the control. [Results] The results indicated that with the prolonging of stress time, the content of chlorophyll was first increased and then decreased, and the content of MDA was increased; soluble sugar content of seedling leaf decreased gradually, while the soluble protein and proline content of seedling leaves were first increased and then decreased; the activities of SOD and POD were displayed a decline trend, meanwhile the activities of CAT was first increased and then decreased. [Conclu- sion] The various indicators showed that under low temperature stress, the chloro- phyll content decreased accompanied with membrane lipid peroxidation and MDA accumulation, and soluble sugar, soluble protein, free proline and antioxidant en- zymes play a protective role in different degrees.展开更多
Actinidia chinensis(kiwifruit)is a perennial horticultural crop species of the Actinidiaceae family with high nutritional and economic value.Two versions of the A.chinensis genomes have been previously assembled,based...Actinidia chinensis(kiwifruit)is a perennial horticultural crop species of the Actinidiaceae family with high nutritional and economic value.Two versions of the A.chinensis genomes have been previously assembled,based mainly on relatively short reads.Here,we report an improved chromosome-level reference genome of A.chinensis(v3.0),based mainly on PacBio long reads and Hi-C data.The high-quality assembled genome is 653 Mb long,with 0.76%heterozygosity.At least 43%of the genome consists of repetitive sequences,and the most abundant long terminal repeats were further identified and account for 23.38%of our novel genome.It has clear improvements in contiguity,accuracy,and gene annotation over the two previous versions and contains 40,464 annotated protein-coding genes,of which 94.41%are functionally annotated.Moreover,further analyses of genetic collinearity revealed that the kiwifruit genome has undergone two whole-genome duplications:one affecting all Ericales families near the K-T extinction event and a recent genus-specific duplication.The reference genome presented here will be highly useful for further molecular elucidation of diverse traits and for the breeding of this horticultural crop,as well as evolutionary studies with related taxa.展开更多
Anthocyanins are a group of secondary metabolites that colour fruit and flowers orange,red,purple or blue depending on a number of factors,such as the basic structure,co-pigmentation,metal ion complexation and vacuola...Anthocyanins are a group of secondary metabolites that colour fruit and flowers orange,red,purple or blue depending on a number of factors,such as the basic structure,co-pigmentation,metal ion complexation and vacuolar pH.The biosynthesis of anthocyanin is regulated at the transcriptional level by a group of transcription factors,the MYB–bHLH–WD40(MBW)complex.In this study,the purple colouration in several kiwifruit(Actinidia)species was identified and characterised as red cyanidin-based and blue delphinidin-based anthocyanins.The differential pigmentation in the skin and flesh can be attributed to the differential ratio of cyanidin and delphinidin derivatives accumulated in the total anthocyanin profile.The expression of anthocyanin biosynthetic genes chalcone synthase(CHS),flavonoid 3-O-glucosyltransferase(F3GT),flavonoid 3′-hydroxylase(F3′H)and flavonoid 3′5′-hydroxylase(F3′5′H)is crucial for anthocyanin accumulation.However,the balance of expression of the F3′H and F3′5′H genes appears responsible for the ratio of cyanidin and delphinidin derivatives,while a lack of CHS,F3GT and MYB110 expression is responsible for a lack of total anthocyanins.The transcriptional regulation of the F3′H and F3′5′H promoters by the R2R3 MYB transcription factor MYB110 is markedly different in tobacco transient assays.When kiwifruit MYB10 or MYB110 are over-expressed in Actinidia chinensis both cyanidin-based and delphinidin-based anthocyanins are elevated,but F3′H and F3′5′H genes are not strongly correlated with MYB expression.These results suggest that the core kiwifruit anthocyanin pathway genes are dependent on characterised MYB transcription factors,while other regulatory proteins are more directly responsible for the expression of the F3′H and F3′5′H genes.展开更多
Actinidia arguta is a berry fruit with high nutritional values.To evaluate the comprehensive quality,the fruit weight,titratable acid(TAC),soluble solids(SSC),vitamin C,mineral elements,and taste value of67 accessions...Actinidia arguta is a berry fruit with high nutritional values.To evaluate the comprehensive quality,the fruit weight,titratable acid(TAC),soluble solids(SSC),vitamin C,mineral elements,and taste value of67 accessions of A.arguta were measured,and sensory attributes including olfactive intensity,juiciness,sweetness,sourness,and astringency were assessed.Cluster analysis was carried out based on mineral elements,and principal component analysis(PCA)was used for comprehensive score ranking.The result demonstrated that fruit weight ranged from 3.5 g to 24.2 g,SSC ranged from 11.94%to 20.56%,TAC ranged from 0.15%to 1.20%,and vitamin C ranged from 3.51 g/kg to 230.76 g/kg(fresh weight)among the tested samples.There were significant differences in sourness,sweetness,bitterness,and umami among the 67 accessions based on electronic tongue analysis,and this result was rapidly and objectively characterized by the sensory assessment.The dendrogram was obtained and clustered the accessions into two major clusters,and five principal components were extracted by PCA.Overall,the information provided by this study identified the 10 best germplasm resources for fresh-eating and processing fruits.It can provide theoretical reference for nutritional efficacy evaluation and food development of A.arguta.展开更多
基金The research is supported by grant from the National Natural Science Foundation of China.
文摘Protoplasts isolated from cotyledon-derived calli of Actinidia chinensis var. chinensis (2n = 2x=58) were fused by the PEG method with cotyledon-callus protoplasts of A. deliciosa var. deliciosa (2n = 6x = 174) or with mesophyll protoplasts of A. kolomikta (2n = 2x = 58), respectively. Randomly amplified polymorphic DNA (RAPD) markers and flow cytometry was used to confirm the occurrence of somatic hybrids. RAPD results with some primers surveyed indicated that one clone (A. chinensis + A. deliciosa) and four clones (A. chinensis + A. kolomikta) had RAPD banding patterns which combined the parental banding profiles. Ploidy levels of the (A. chinensis + A. deliciosa) clone were deduced as octoploid (2n = 8x), and the (A. chinensis + A. kolomikta) clones were tetraploid (2n = 4x), triploid (2n = 3x) or pentaploid (2n = 5x). The clones were confirmed as interspecific somatic hybrids in Actinidia.
基金supported by grants from the National Key Research and Development Program of China(Grant No.2022YFD1400200)the Special Support Plan for High-Level Talent of Shaanxi Provincethe First-Class Universities and Academic Programs of Northwest A&F University.
文摘Pseudomonas syringae pv.actinidiae(Psa)causes destructive kiwifruit bacterial canker by invading vascular tissues across multiple plant organs.However,the cellular mechanism underlying its systemic transmission and cell-to-cell movement within these specialized vascular conduits remains unclear.In this study,a Psa-GFP strain and various microscopic techniques were used to investigate the interaction between kiwifruit and Psa.Our results reveal that Psa strategically exploits host vascular conduits for systemic movement,with the xylem vessel being the predominant avenue.In the phloem,Psa exhibits adaptive alteration in bacterial shape to traverse sieve pores,facilitating its systemic spread along sieve tubes and inducing phloem necrosis.Within the xylem,Psa breaches pit membranes to migrate between adjacent vessels.Furthermore,phloem fibers act as an initial barrier at the early stages of infection,delaying Psa's entry into vascular tissues during its journey to the xylem.Additionally,at the junctions of stem-stem or stem-leaf,branch trace or leaf trace mediates the bacterial organ-to-organ translocation,thus facilitating the systemic progression of disease.In conclusion,our findings shed light on the cellular mechanism employed by Psa to exploit the woody plant's vascular network for infection,thereby enhancing a better understanding of the biology of this poorly defined bacterium.These insights carry implications for the pathogenesis of Psa and other vascular pathogens,offering theoretical guidance for effective control strategies.
基金Supported by the Special Science Foundation of Jiangxi Province(20143ACF60015)National Natural Scientific Fund(31360472)~~
文摘[Objective] The variation of sugar, acid and AsA contents in fruits of ‘Ganmi 6＇ kiwifruit （Actinidia eriantha Benth） were investigated during fruit develop- ment. [Method] Kiwi fruits were randomly taken as materials every 15 days since 20 days after full bloom （DAFB） to 170 DAFB until in mature stage. [Result] The results showed that during fruit development of ‘Ganmi 6＇, the total sugar soluble contents had a rising trend with relatively stable at 95 DAFB, then rose until har- vest with the maximum content （10.35%）. The titratable acid content showed a trend of increasing, then declining, then increase to the harvest content （1.10%）. From the sugar acid ratio, we can knew it decreased in 95 DAFB, then up to the max （9.38）. The changes of AsA contents showed double ‘S＇ shape, decreased af- ter the first increased rapidly, slightly increased and then decreased in the early harvest. [Conclusion] It provided a theoretical basis for scientific cultivation methods to explore the nutrients regulation.
基金Supported by the Special Fund for Agro-scientific Research in the Public Interest (201303093)the Key Project for Agricultural Improved Variety Breeding of Shandong Province (Lunongliang[2016]No.6~~
文摘[Objective] To study the ecophysiological effects of low temperature stress on Actinidia arguta （Seib.et.Zucc.）, and provide a theoretical basis for the introduc- tion and breeding of cold resistant varieties. [Method] A. arguta as the test material was processed at room temperature of 4 ℃ to determine the contents of chloro- phyll, water soluble sugar, water soluble protein, free proline, MDA, and antioxidant enzymes （POD activity, SOD activity, CAT activity） with the treatment at 25℃ as the control. [Results] The results indicated that with the prolonging of stress time, the content of chlorophyll was first increased and then decreased, and the content of MDA was increased; soluble sugar content of seedling leaf decreased gradually, while the soluble protein and proline content of seedling leaves were first increased and then decreased; the activities of SOD and POD were displayed a decline trend, meanwhile the activities of CAT was first increased and then decreased. [Conclu- sion] The various indicators showed that under low temperature stress, the chloro- phyll content decreased accompanied with membrane lipid peroxidation and MDA accumulation, and soluble sugar, soluble protein, free proline and antioxidant en- zymes play a protective role in different degrees.
基金supported by the National Key Research and Development Program of China(ref.2017YFC0505203)Fundamental Research Funds for the Central Universities(ref.2018CDDY-S02-SCU)+1 种基金National High-Level Talents Special Support Plan(10 Thousand Talents Plan)985 and 211 Projects of Sichuan University.
文摘Actinidia chinensis(kiwifruit)is a perennial horticultural crop species of the Actinidiaceae family with high nutritional and economic value.Two versions of the A.chinensis genomes have been previously assembled,based mainly on relatively short reads.Here,we report an improved chromosome-level reference genome of A.chinensis(v3.0),based mainly on PacBio long reads and Hi-C data.The high-quality assembled genome is 653 Mb long,with 0.76%heterozygosity.At least 43%of the genome consists of repetitive sequences,and the most abundant long terminal repeats were further identified and account for 23.38%of our novel genome.It has clear improvements in contiguity,accuracy,and gene annotation over the two previous versions and contains 40,464 annotated protein-coding genes,of which 94.41%are functionally annotated.Moreover,further analyses of genetic collinearity revealed that the kiwifruit genome has undergone two whole-genome duplications:one affecting all Ericales families near the K-T extinction event and a recent genus-specific duplication.The reference genome presented here will be highly useful for further molecular elucidation of diverse traits and for the breeding of this horticultural crop,as well as evolutionary studies with related taxa.
基金Research is supported by The New Zealand Government,Ministry of Business,Innovation and Employment Endeavour Fund(MBIE),‘Turbo Breeding’(C11X1602)and MBIE‘Filling the Void’(C11X1704).YP is supported by the Joint Graduate School in Plant and Food Science,University of Auckland.
文摘Anthocyanins are a group of secondary metabolites that colour fruit and flowers orange,red,purple or blue depending on a number of factors,such as the basic structure,co-pigmentation,metal ion complexation and vacuolar pH.The biosynthesis of anthocyanin is regulated at the transcriptional level by a group of transcription factors,the MYB–bHLH–WD40(MBW)complex.In this study,the purple colouration in several kiwifruit(Actinidia)species was identified and characterised as red cyanidin-based and blue delphinidin-based anthocyanins.The differential pigmentation in the skin and flesh can be attributed to the differential ratio of cyanidin and delphinidin derivatives accumulated in the total anthocyanin profile.The expression of anthocyanin biosynthetic genes chalcone synthase(CHS),flavonoid 3-O-glucosyltransferase(F3GT),flavonoid 3′-hydroxylase(F3′H)and flavonoid 3′5′-hydroxylase(F3′5′H)is crucial for anthocyanin accumulation.However,the balance of expression of the F3′H and F3′5′H genes appears responsible for the ratio of cyanidin and delphinidin derivatives,while a lack of CHS,F3GT and MYB110 expression is responsible for a lack of total anthocyanins.The transcriptional regulation of the F3′H and F3′5′H promoters by the R2R3 MYB transcription factor MYB110 is markedly different in tobacco transient assays.When kiwifruit MYB10 or MYB110 are over-expressed in Actinidia chinensis both cyanidin-based and delphinidin-based anthocyanins are elevated,but F3′H and F3′5′H genes are not strongly correlated with MYB expression.These results suggest that the core kiwifruit anthocyanin pathway genes are dependent on characterised MYB transcription factors,while other regulatory proteins are more directly responsible for the expression of the F3′H and F3′5′H genes.
基金supported by Special Scientific Research Fund of Agricultural Public Welfare Profession of China[grant number 200903013]Liaoning Province,Shenyang Agricultural University,high-end talent introduction fund project[grant number SYAU20160003]。
文摘Actinidia arguta is a berry fruit with high nutritional values.To evaluate the comprehensive quality,the fruit weight,titratable acid(TAC),soluble solids(SSC),vitamin C,mineral elements,and taste value of67 accessions of A.arguta were measured,and sensory attributes including olfactive intensity,juiciness,sweetness,sourness,and astringency were assessed.Cluster analysis was carried out based on mineral elements,and principal component analysis(PCA)was used for comprehensive score ranking.The result demonstrated that fruit weight ranged from 3.5 g to 24.2 g,SSC ranged from 11.94%to 20.56%,TAC ranged from 0.15%to 1.20%,and vitamin C ranged from 3.51 g/kg to 230.76 g/kg(fresh weight)among the tested samples.There were significant differences in sourness,sweetness,bitterness,and umami among the 67 accessions based on electronic tongue analysis,and this result was rapidly and objectively characterized by the sensory assessment.The dendrogram was obtained and clustered the accessions into two major clusters,and five principal components were extracted by PCA.Overall,the information provided by this study identified the 10 best germplasm resources for fresh-eating and processing fruits.It can provide theoretical reference for nutritional efficacy evaluation and food development of A.arguta.
