Heavy metal accumulation in agricultural soil is primarily driven by pesticides,polluted water,and industrial gas emissions,which pose threats to sustainable crop production.Chromium(Cr)stress has an adverse impact on...Heavy metal accumulation in agricultural soil is primarily driven by pesticides,polluted water,and industrial gas emissions,which pose threats to sustainable crop production.Chromium(Cr)stress has an adverse impact on plant development and metabolism,but approaches to reduce its toxicity and enhance plant resistance remain limited.Melatonin is a potent antioxidant involved in regulating various morpho-physiological functions of plants under different abiotic stresses.In this study,we investigated the impact of exogenous melatonin to mitigate the negative effects of potassium dichromate(PD)stress in melon plants and analyzed genetic modulation of morphological,physiological,and biochemical parameters.The obtained results revealed that melatonin treatment(100μmol L^(−1))considerably improved seed germination rate,promoted plant growth,and stabilized chloroplast ultrastructure of leaves under PD-stress.This physiological resilience was similarly reflected by maintained photosynthetic efficiency and significantly stabilized photochemical parameters(e.g.,Fv/Fm and NPQ).At the molecular level,quantitative polymerase chain reaction(qPCR)analysis confirmed that melatonin treatment maintained organelle integrity by upregulating primary metabolism indices and hindering Cr accumulation.Specifically,melatonin reduced the Cr-induced downregulation of chlorophyll biosynthesis genes[CmHEMA(MELO3C006296.2),CmGOGAT(MELO3C008481.2),and CmPOR(MELO3C016714.2)],restoring chlorophyll content by up to 5.08 mg·g^(−1),increased by 67.11%.The expression level of genes[CmSPS(MELO3C003715.2),CmPEPC(MELO3C018724.2),and CmRubisco(MELO3C012180.2)]showed an effective upsurge in carbohydrate synthesis.Moreover,melatonin significantly enhanced the antioxidant system[e.g.,increasing SOD(46.13%),POD(35.85%),and APX(25.00%)activities]and promoted the accumulation of lignin and metallothionein[via upregulation of Cm4CL(MELO3C002346.2)and CmMet(MELO3C016513.2)genes],which restricted Cr translocation from the root to the shoot.To summarize,exogenous melatonin application could serve as an effective strategy for mitigating Cr-induced stress in melon by stabilizing basic photosynthetic processes and secondary metabolism through biochemical and molecular defensive mechanisms,thereby preventing Cr translocation by activating the accumulation of secondary metabolites(e.g.,lignin and metallothionein)and photo-respiration elements.Our findings provided new perspective to understand melatonin as a viable,multidimensional bio-regulator for improving crop resilience in Cr-polluted agricultural systems.展开更多
[Objectives]To investigate the chemical composition,antioxidant property,and nematicidal activity of Cucumis metuliferus and establish a theoretical foundation for the development of botanical nematicides.[Methods]The...[Objectives]To investigate the chemical composition,antioxidant property,and nematicidal activity of Cucumis metuliferus and establish a theoretical foundation for the development of botanical nematicides.[Methods]The compounds were isolated and purified using silica gel,reversed-phase medium,low-pressure gel Sephadex LH-20 column chromatography,and preparative high-performance liquid chromatography.Their identification was based on physicochemical properties,various spectral analyses,and data reported in the literature.Subsequently,the nematicidal and antioxidant activities of the isolated compounds were evaluated.[Results]A total of four compounds were isolated from C.metuliferus,which were identified as isovitexin-2″-O-glucoside(compound 1),9E,11E-(13-oxo)tridecadienoic acid(compound 2),2E,4E-tridecadienedioic acid(compound 3),and 9E,11E-(13-hydroxy)tridecadienoic acid(compound 4).Compound 1 demonstrated a notable degree of antioxidant activity,achieving a DPPH scavenging rate of 49.40%at a mass concentration of 1 mg/mL.Additionally,compounds 1,3,and 4 exhibited varying levels of nematicidal activity.Specifically,compound 1 displayed strong nematicidal activity at a concentration of 2.0 mg/mL,resulting in a mortality rate of 90.5%against nematodes.Furthermore,compounds 3 and 4 achieved a mortality rate of 100%against nematodes at a concentration of 0.25 mg/mL.[Conclusions]This study reports the first isolation of four compounds:isovitexin-2″-O-glucoside,9E,11E-(13-oxo)tridecadienoic acid,2E,4E-tridecadienedioic acid,and 9E,11E-(13-hydroxy)tridecadienoic acid from C.metuliferus.Notably,2E,4E-tridecadienedioic acid and 9E,11E-(13-oxo)tridecadienoic acid are identified as novel natural products.Among these compounds,isovitexin-2″-O-glucoside,9E,11E-(13-oxo)tridecadienoic acid,and 9E,11E-(13-hydroxy)tridecadienoic acid exhibit nematicidal activity,whereas isovitexin-2″-O-glucoside demonstrates antioxidant properties.展开更多
To understand the inter-hybridization between Cucumis ssp.plants,we used 150 melon varieties as female parents to cross with Cucumis metuliferus and Cucumis anguria.Only melon accessions V2 and V129 set fruits,but see...To understand the inter-hybridization between Cucumis ssp.plants,we used 150 melon varieties as female parents to cross with Cucumis metuliferus and Cucumis anguria.Only melon accessions V2 and V129 set fruits,but seeds from fruits V2（V129）×C.metuliferus were abortive.A few of seeds from the bottom of fruit V2（V129）×C.anguria were fertile.Sequence-related amplified polymorphism（SRAP）molecular markers were used to analyze the progenies of inter-specific hybridization between C.anguria and melon V129.One pair primer（E14/M2）was found effective in amplification on male parent characteristic bands from the hybrids,suggesting that some DNA exchange had happened between C.anguria and melon V129.This study provided data for analyzing the mechanism of inter-hybridization between Cucumis plants.展开更多
[Objective] The study was carried out to research the adaptability of Cucumis hystrix Chakr.under aluminum salt stress.[Method] Using Cucumis hystrix Chakr.and three cultivated cucumbers as tested materials,the change...[Objective] The study was carried out to research the adaptability of Cucumis hystrix Chakr.under aluminum salt stress.[Method] Using Cucumis hystrix Chakr.and three cultivated cucumbers as tested materials,the change of physiological indexes including POD activity,SOD activity,electrolyte leakage and the content of malondialdehyde（MDA）,proline（Pro）content and soluble sugar were studied.[Result] The POD activity,SOD activity,proline content and soluble sugar content of Cucumis hystrix were higher than these of cultivated cucumbers,while electrolyte leakage and MDA content were lower,and it showed that Cucumis hystrix had better adaptability under aluminum salt stress.[Conclusion] Our study could lay a foundation for the improvement of cultivated cucumber by using the excellent characteristics of Cucumis hystrix.展开更多
Spectrin-like protein has been found in a variety of plant cells. In this study, electron microscopic observation of immuno-gold labelled preparations from the leaf petiole of cucumber ( Cucumis sativus L.) shows that...Spectrin-like protein has been found in a variety of plant cells. In this study, electron microscopic observation of immuno-gold labelled preparations from the leaf petiole of cucumber ( Cucumis sativus L.) shows that it also exists in the sieve element-companion cell (SE-CC) complex, being widely distributed in P-protein filaments and sieve element reticulum (SER), in the cytoplasm and mitochondrial membrane of companion cell (CC) and in the branched plasmodesmata between sieve element (SE) and CC as well. The results suggest that this protein could be synthesized in CC and transferred to SE through plasmodesmata. Western blotting showed that spectrin-like protein existed in the protein of phloem exudate of cucumber, and its molecular weight was about 260 kD.展开更多
OBJECTIVE: To investigate the efficacy and safety of intravenous cervus and cucumis polypeptides for treating avascular necrosis of the femoral head(ANFH) in regard to pain and hip function in a randomized clinical tr...OBJECTIVE: To investigate the efficacy and safety of intravenous cervus and cucumis polypeptides for treating avascular necrosis of the femoral head(ANFH) in regard to pain and hip function in a randomized clinical trial.METHODS: A total of 96 subjects with ANFH who were recruited at the Orthopaedic Hospital Affiliated with Hebei United University and Qian Hai Femoral Head Hospital of Beijing were assigned by lottery to an intervention group(n = 48) or a control group(n = 48). All subjects underwent physical therapy and rehabilitation exercises. In addition,subjects in the intervention group were given intravenous infusions of cervus and cucumis polypeptides. Visual analogue scale(VAS), Harris hip score,and radiography or magnetic resonance imaging were applied to assess all subjects at the beginning of treatment and 3, 6, and 9 months afterward. All the subjects were followed up for 2 years.RESULTS: At the beginning of treatment, there were no statistically significant differences between the two groups in terms of the general condition of patients or the VAS and Harris hip scores(all P > 0.05). At 3, 6, and 9 months after treatment,however, the VAS score decreased and the Harris hip score increased in all patients, with the improvement of intervention group significantly greater than that of the control group(P < 0.05).The total effectiveness rates for the intervention and control groups were 89.58% and 70.83%, respectively, with the difference being statistically significant(P < 0.05). There was no statistically significant difference between the two groups in terms of the safety of the injections(P > 0.05).CONCLUSION: Intravenous infusion of cervus and cucumis polypeptides relieved pain and improved hip function of subjects with ANFH.Thus, the intravenous infusion of cervus and cucumis polypeptides was a safe, effective treatment for ANFH.展开更多
Genetic transformation is an important technique for functional genomics study and genetic improvement of plants. Until now, Agrobacterium-mediated transformation methods using cotyledon as explants has been the major...Genetic transformation is an important technique for functional genomics study and genetic improvement of plants. Until now, Agrobacterium-mediated transformation methods using cotyledon as explants has been the major approach for cucumber, and its frequency has been up to 23%. For example, significantly enhancement of the transformation efficiency of this plant species was achieved from the cotyledon explants of the cultivar Poinsett 76 infected by Agrobacterium strains EHA105 with efficient positive selection system in lots of experiments. This review is to summarize some key factors influencing cucumber regeneration and genetic transformation, including target genes, selection systems and the ways of transgene introduction, and then to put forward some strategies for the increasing of cucumber transformation efficiency. In the future, it is high possible for cucumber to be potential bioreactor to produce vaccine and biomaterials for human beings.展开更多
Cucumber powdery mildew is one of the most destructive diseases of cucumber throughout the world. In the present study, inheritance of powdery mildew resistance in three crosses, and linkage of resistance with amplifi...Cucumber powdery mildew is one of the most destructive diseases of cucumber throughout the world. In the present study, inheritance of powdery mildew resistance in three crosses, and linkage of resistance with amplified fragment length polymorphism （AFLP） markers are studied to formulate efficient strategies for breeding cultivars resistant to powdery mildew. The joint analysis of multiple generations and AFLP technique has been applied in this study. The best model is the one with two major genes, additive, dominant, and epistatic effects, plus polygenes with additive, dominant, and epistatic effects （E-l-0 model）. The heritabilities of the major genes varied from 64.26% to 97.82%, and susceptibility was incompletely dominant for the two major genes in the three crosses studied. The additive effects of the two major genes and the dominant effect of the second major gene were high, and the epistatic effect of the additive-dominant between the two major genes was the highest in cross I . In cross II, the absolute value of the additive effect, dominant effect, and potential ratio of the first major gene were far higher than those of the second major gene, and the epistatic effect of the additive-additive was the highest. The genetic parameters of the two major genes in cross III were similar to those in cross II. Correlation and regression analyses showed that marker E25/M63-103 was linked to a susceptible gene controlling powdery mildew resistance. The marker could account for 19.98% of the phenotypic variation. When the marker was tested on a diverse set of 29 cucumber lines, the correlation between phenotype and genotype was not significant, which suggested cultivar specialty of gene expression or different methods of resistance to powdery mildew. The target DNA fragment was 103 bp in length, and only a small part was found to be homologous to DNA in the other species evaluated, which indicated that it was unique to the cucumber genome.展开更多
Interspecific hybridization and allopolyploidization contribute to the improvement of many important crops. Recently, we successfully developed an amphidiploid from an interspecific cross between cucumber(Cucumis sati...Interspecific hybridization and allopolyploidization contribute to the improvement of many important crops. Recently, we successfully developed an amphidiploid from an interspecific cross between cucumber(Cucumis sativus, 2n = 2x = 14) and its relative C. hystrix(2n = 2x = 24) followed by chemical induction of chromosome doubling. The resulting allotetraploid plant was self-pollinated for three generations. The fertility and seed set of the amphidiploid plants were very low. In this study, we investigated the meiotic chromosome behavior in pollen mother cells with the aid of fluorescence in situ hybridization, aiming to identify the reasons for the low fertility and seed set in the amphidiploid plants. Homologous chromosome pairing appeared normal, but chromosome laggards were common, owing primarily to asynchronous meiosis of chromosomes from the two donor genomes. We suggest that asynchronous meiotic rhythm between the two parental genomes is the main reason for the low fertility and low seed set of the C. hystrix–cucumber amphidiploid plants.展开更多
P450(cytochrome P450)is a supergene family,which is involved in various metabolic pathways in plants.Based on previous study,we found some of cucumber P450 mRNAs were systemic mobile in cucumber/pumpkin grafts.However...P450(cytochrome P450)is a supergene family,which is involved in various metabolic pathways in plants.Based on previous study,we found some of cucumber P450 mRNAs were systemic mobile in cucumber/pumpkin grafts.However,the reason that why P450 mRNAs were endorsed as signaling,and what specific motif(s)did they harbored is not clear yet.Here,we first identified 221 CsaP450 genes in cucumber genomewide level.Combining with graft-transmissiblemRNAs datasets in cucumber,we elucidated 15mobile-CsaP450-coding genes,of which 5 and 10 belonged to A-type and non-A type respectively.Compared with Arabidopsis and pumpkin(Cucubit moschata)graft-induced-transmissible P450 mRNAs,a phylogenetic treewas constructed and divided into eight clans by usingmultiple-sequence alignment.Gene ontology(GO)enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG)annotations indicated that the expression patterns of the mobile-mRNA-coding CsaP450 genes in different tissues of cucumber was specifically enriched in oxidoreductase activity and secondary metabolic pathways.The structures and motifs of these 15 mobile-mRNA-coding CsaP450 genes and their types of regulatory elements told that the proportion of CU-rich motifs was higher than nonmobile-mRNA-coding CsaP450 genes.The integrated analysis of mobility direction and mRNA abundance of 15 mobilemRNA-coding CsaP450 genes allowed to conclude that there was rarely relationship between them.The study provided a new insight into the relationship between the motifs and functional characterization of mobile-mRNA-coding P450 genes of cucumber in genome-wide levels.展开更多
基金funded by the Key Research and Development Plan of Heilongjiang Province(Award number:SC2022ZX02C0202-06)the Heilongjiang Provincial Research Fund(Award number:CZKYF2025-1-B004)the Heilongjiang Academy of Agricultural Sciences Innovation Project(Award numbers:CX25YQ30 and CX24ZH10).
文摘Heavy metal accumulation in agricultural soil is primarily driven by pesticides,polluted water,and industrial gas emissions,which pose threats to sustainable crop production.Chromium(Cr)stress has an adverse impact on plant development and metabolism,but approaches to reduce its toxicity and enhance plant resistance remain limited.Melatonin is a potent antioxidant involved in regulating various morpho-physiological functions of plants under different abiotic stresses.In this study,we investigated the impact of exogenous melatonin to mitigate the negative effects of potassium dichromate(PD)stress in melon plants and analyzed genetic modulation of morphological,physiological,and biochemical parameters.The obtained results revealed that melatonin treatment(100μmol L^(−1))considerably improved seed germination rate,promoted plant growth,and stabilized chloroplast ultrastructure of leaves under PD-stress.This physiological resilience was similarly reflected by maintained photosynthetic efficiency and significantly stabilized photochemical parameters(e.g.,Fv/Fm and NPQ).At the molecular level,quantitative polymerase chain reaction(qPCR)analysis confirmed that melatonin treatment maintained organelle integrity by upregulating primary metabolism indices and hindering Cr accumulation.Specifically,melatonin reduced the Cr-induced downregulation of chlorophyll biosynthesis genes[CmHEMA(MELO3C006296.2),CmGOGAT(MELO3C008481.2),and CmPOR(MELO3C016714.2)],restoring chlorophyll content by up to 5.08 mg·g^(−1),increased by 67.11%.The expression level of genes[CmSPS(MELO3C003715.2),CmPEPC(MELO3C018724.2),and CmRubisco(MELO3C012180.2)]showed an effective upsurge in carbohydrate synthesis.Moreover,melatonin significantly enhanced the antioxidant system[e.g.,increasing SOD(46.13%),POD(35.85%),and APX(25.00%)activities]and promoted the accumulation of lignin and metallothionein[via upregulation of Cm4CL(MELO3C002346.2)and CmMet(MELO3C016513.2)genes],which restricted Cr translocation from the root to the shoot.To summarize,exogenous melatonin application could serve as an effective strategy for mitigating Cr-induced stress in melon by stabilizing basic photosynthetic processes and secondary metabolism through biochemical and molecular defensive mechanisms,thereby preventing Cr translocation by activating the accumulation of secondary metabolites(e.g.,lignin and metallothionein)and photo-respiration elements.Our findings provided new perspective to understand melatonin as a viable,multidimensional bio-regulator for improving crop resilience in Cr-polluted agricultural systems.
基金Supported by Natural Science Foundation Project of Xinjiang Uygur Autonomous Region(2021D01B59)Youth Science and Technology Backbone Project of Xinjiang Academy of Agricultural Sciences(XJNKQ-2021011)+2 种基金General Program of Hainan Natural Science Foundation(319MS109)Major Science and Technology Program of Hainan Province(ZDKJ2021005)Specific Research Fund of the Innovation Platform for Academicians of Hainan Province(YSPTZX202141).
文摘[Objectives]To investigate the chemical composition,antioxidant property,and nematicidal activity of Cucumis metuliferus and establish a theoretical foundation for the development of botanical nematicides.[Methods]The compounds were isolated and purified using silica gel,reversed-phase medium,low-pressure gel Sephadex LH-20 column chromatography,and preparative high-performance liquid chromatography.Their identification was based on physicochemical properties,various spectral analyses,and data reported in the literature.Subsequently,the nematicidal and antioxidant activities of the isolated compounds were evaluated.[Results]A total of four compounds were isolated from C.metuliferus,which were identified as isovitexin-2″-O-glucoside(compound 1),9E,11E-(13-oxo)tridecadienoic acid(compound 2),2E,4E-tridecadienedioic acid(compound 3),and 9E,11E-(13-hydroxy)tridecadienoic acid(compound 4).Compound 1 demonstrated a notable degree of antioxidant activity,achieving a DPPH scavenging rate of 49.40%at a mass concentration of 1 mg/mL.Additionally,compounds 1,3,and 4 exhibited varying levels of nematicidal activity.Specifically,compound 1 displayed strong nematicidal activity at a concentration of 2.0 mg/mL,resulting in a mortality rate of 90.5%against nematodes.Furthermore,compounds 3 and 4 achieved a mortality rate of 100%against nematodes at a concentration of 0.25 mg/mL.[Conclusions]This study reports the first isolation of four compounds:isovitexin-2″-O-glucoside,9E,11E-(13-oxo)tridecadienoic acid,2E,4E-tridecadienedioic acid,and 9E,11E-(13-hydroxy)tridecadienoic acid from C.metuliferus.Notably,2E,4E-tridecadienedioic acid and 9E,11E-(13-oxo)tridecadienoic acid are identified as novel natural products.Among these compounds,isovitexin-2″-O-glucoside,9E,11E-(13-oxo)tridecadienoic acid,and 9E,11E-(13-hydroxy)tridecadienoic acid exhibit nematicidal activity,whereas isovitexin-2″-O-glucoside demonstrates antioxidant properties.
基金Supported by Special Basic Research Fund for Central Public Research Institutes(0032011018)~~
文摘To understand the inter-hybridization between Cucumis ssp.plants,we used 150 melon varieties as female parents to cross with Cucumis metuliferus and Cucumis anguria.Only melon accessions V2 and V129 set fruits,but seeds from fruits V2（V129）×C.metuliferus were abortive.A few of seeds from the bottom of fruit V2（V129）×C.anguria were fertile.Sequence-related amplified polymorphism（SRAP）molecular markers were used to analyze the progenies of inter-specific hybridization between C.anguria and melon V129.One pair primer（E14/M2）was found effective in amplification on male parent characteristic bands from the hybrids,suggesting that some DNA exchange had happened between C.anguria and melon V129.This study provided data for analyzing the mechanism of inter-hybridization between Cucumis plants.
基金Supported by National Natural Science Foundation of China(30671419)~~
文摘[Objective] The study was carried out to research the adaptability of Cucumis hystrix Chakr.under aluminum salt stress.[Method] Using Cucumis hystrix Chakr.and three cultivated cucumbers as tested materials,the change of physiological indexes including POD activity,SOD activity,electrolyte leakage and the content of malondialdehyde（MDA）,proline（Pro）content and soluble sugar were studied.[Result] The POD activity,SOD activity,proline content and soluble sugar content of Cucumis hystrix were higher than these of cultivated cucumbers,while electrolyte leakage and MDA content were lower,and it showed that Cucumis hystrix had better adaptability under aluminum salt stress.[Conclusion] Our study could lay a foundation for the improvement of cultivated cucumber by using the excellent characteristics of Cucumis hystrix.
文摘Spectrin-like protein has been found in a variety of plant cells. In this study, electron microscopic observation of immuno-gold labelled preparations from the leaf petiole of cucumber ( Cucumis sativus L.) shows that it also exists in the sieve element-companion cell (SE-CC) complex, being widely distributed in P-protein filaments and sieve element reticulum (SER), in the cytoplasm and mitochondrial membrane of companion cell (CC) and in the branched plasmodesmata between sieve element (SE) and CC as well. The results suggest that this protein could be synthesized in CC and transferred to SE through plasmodesmata. Western blotting showed that spectrin-like protein existed in the protein of phloem exudate of cucumber, and its molecular weight was about 260 kD.
基金Supported by Tangshan Science and Technology Research Project(No.13130242b)
文摘OBJECTIVE: To investigate the efficacy and safety of intravenous cervus and cucumis polypeptides for treating avascular necrosis of the femoral head(ANFH) in regard to pain and hip function in a randomized clinical trial.METHODS: A total of 96 subjects with ANFH who were recruited at the Orthopaedic Hospital Affiliated with Hebei United University and Qian Hai Femoral Head Hospital of Beijing were assigned by lottery to an intervention group(n = 48) or a control group(n = 48). All subjects underwent physical therapy and rehabilitation exercises. In addition,subjects in the intervention group were given intravenous infusions of cervus and cucumis polypeptides. Visual analogue scale(VAS), Harris hip score,and radiography or magnetic resonance imaging were applied to assess all subjects at the beginning of treatment and 3, 6, and 9 months afterward. All the subjects were followed up for 2 years.RESULTS: At the beginning of treatment, there were no statistically significant differences between the two groups in terms of the general condition of patients or the VAS and Harris hip scores(all P > 0.05). At 3, 6, and 9 months after treatment,however, the VAS score decreased and the Harris hip score increased in all patients, with the improvement of intervention group significantly greater than that of the control group(P < 0.05).The total effectiveness rates for the intervention and control groups were 89.58% and 70.83%, respectively, with the difference being statistically significant(P < 0.05). There was no statistically significant difference between the two groups in terms of the safety of the injections(P > 0.05).CONCLUSION: Intravenous infusion of cervus and cucumis polypeptides relieved pain and improved hip function of subjects with ANFH.Thus, the intravenous infusion of cervus and cucumis polypeptides was a safe, effective treatment for ANFH.
基金financially supported by grants from the Biogreen 21 Program, RDA, Korea (PJ00810304)the Agricultural Science and Technology Innovation Program (ASTIP) of Chinese Academy of Agricultural Sciences (2014–2015)the Beijing Municipal Education Commission, China (KM200910011001)
文摘Genetic transformation is an important technique for functional genomics study and genetic improvement of plants. Until now, Agrobacterium-mediated transformation methods using cotyledon as explants has been the major approach for cucumber, and its frequency has been up to 23%. For example, significantly enhancement of the transformation efficiency of this plant species was achieved from the cotyledon explants of the cultivar Poinsett 76 infected by Agrobacterium strains EHA105 with efficient positive selection system in lots of experiments. This review is to summarize some key factors influencing cucumber regeneration and genetic transformation, including target genes, selection systems and the ways of transgene introduction, and then to put forward some strategies for the increasing of cucumber transformation efficiency. In the future, it is high possible for cucumber to be potential bioreactor to produce vaccine and biomaterials for human beings.
文摘Cucumber powdery mildew is one of the most destructive diseases of cucumber throughout the world. In the present study, inheritance of powdery mildew resistance in three crosses, and linkage of resistance with amplified fragment length polymorphism （AFLP） markers are studied to formulate efficient strategies for breeding cultivars resistant to powdery mildew. The joint analysis of multiple generations and AFLP technique has been applied in this study. The best model is the one with two major genes, additive, dominant, and epistatic effects, plus polygenes with additive, dominant, and epistatic effects （E-l-0 model）. The heritabilities of the major genes varied from 64.26% to 97.82%, and susceptibility was incompletely dominant for the two major genes in the three crosses studied. The additive effects of the two major genes and the dominant effect of the second major gene were high, and the epistatic effect of the additive-dominant between the two major genes was the highest in cross I . In cross II, the absolute value of the additive effect, dominant effect, and potential ratio of the first major gene were far higher than those of the second major gene, and the epistatic effect of the additive-additive was the highest. The genetic parameters of the two major genes in cross III were similar to those in cross II. Correlation and regression analyses showed that marker E25/M63-103 was linked to a susceptible gene controlling powdery mildew resistance. The marker could account for 19.98% of the phenotypic variation. When the marker was tested on a diverse set of 29 cucumber lines, the correlation between phenotype and genotype was not significant, which suggested cultivar specialty of gene expression or different methods of resistance to powdery mildew. The target DNA fragment was 103 bp in length, and only a small part was found to be homologous to DNA in the other species evaluated, which indicated that it was unique to the cucumber genome.
基金supported by Agriculture and Food Research Initiative Competitive Grant 2013-67013-21105 from the U.S. Department of Agriculture National Institute of Food to YWthe National Natural Science Foundation of China to YH (No. 31271350)
文摘Interspecific hybridization and allopolyploidization contribute to the improvement of many important crops. Recently, we successfully developed an amphidiploid from an interspecific cross between cucumber(Cucumis sativus, 2n = 2x = 14) and its relative C. hystrix(2n = 2x = 24) followed by chemical induction of chromosome doubling. The resulting allotetraploid plant was self-pollinated for three generations. The fertility and seed set of the amphidiploid plants were very low. In this study, we investigated the meiotic chromosome behavior in pollen mother cells with the aid of fluorescence in situ hybridization, aiming to identify the reasons for the low fertility and seed set in the amphidiploid plants. Homologous chromosome pairing appeared normal, but chromosome laggards were common, owing primarily to asynchronous meiosis of chromosomes from the two donor genomes. We suggest that asynchronous meiotic rhythm between the two parental genomes is the main reason for the low fertility and low seed set of the C. hystrix–cucumber amphidiploid plants.
基金supported by National Key Research and Development Program of China(Grant Nos.2018YFD1000800 and 2019YFD1000300)National Natural Science Foundation of China(Grant No.31872158)Earmarked Fund for China Agriculture Research System(Grant No.CAS-23).
文摘P450(cytochrome P450)is a supergene family,which is involved in various metabolic pathways in plants.Based on previous study,we found some of cucumber P450 mRNAs were systemic mobile in cucumber/pumpkin grafts.However,the reason that why P450 mRNAs were endorsed as signaling,and what specific motif(s)did they harbored is not clear yet.Here,we first identified 221 CsaP450 genes in cucumber genomewide level.Combining with graft-transmissiblemRNAs datasets in cucumber,we elucidated 15mobile-CsaP450-coding genes,of which 5 and 10 belonged to A-type and non-A type respectively.Compared with Arabidopsis and pumpkin(Cucubit moschata)graft-induced-transmissible P450 mRNAs,a phylogenetic treewas constructed and divided into eight clans by usingmultiple-sequence alignment.Gene ontology(GO)enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG)annotations indicated that the expression patterns of the mobile-mRNA-coding CsaP450 genes in different tissues of cucumber was specifically enriched in oxidoreductase activity and secondary metabolic pathways.The structures and motifs of these 15 mobile-mRNA-coding CsaP450 genes and their types of regulatory elements told that the proportion of CU-rich motifs was higher than nonmobile-mRNA-coding CsaP450 genes.The integrated analysis of mobility direction and mRNA abundance of 15 mobilemRNA-coding CsaP450 genes allowed to conclude that there was rarely relationship between them.The study provided a new insight into the relationship between the motifs and functional characterization of mobile-mRNA-coding P450 genes of cucumber in genome-wide levels.
