The intergeneric hybridization between Brassica napus L. cv. oro and Matthiola incana (L.) R. Br. was carried out to study the phytogenetic peculiarities of the hybrid plants. In order to improve the oil quality of ra...The intergeneric hybridization between Brassica napus L. cv. oro and Matthiola incana (L.) R. Br. was carried out to study the phytogenetic peculiarities of the hybrid plants. In order to improve the oil quality of rape seed, ovaries of B. napus pollinated with pollen of M. incana, were cut off and inoculated onto MS media supplemented with various plant hormones at the 7th day after pollination. Two mature embryos were obtained from 750 pollinated ovaries cultured in vitro. The percentage of seed set was 0.26%. The mature embryos were transferred onto the MS media supplemented with 2.0 mg/L 6-BA + 0.1 mg/L NAA, and a compound bud was produced later. The compound bud was then cut into a number of single buds, which were transferred onto fresh media. Twenty-two plantlets in vitro were developed from the above single buds. The hybrid plants (F-1) were basically intermediate between the two parents in many,characters with a few showing hybrid vigor. The fertility of hybrid plants (F-1) was poor. Cytological studies revealed that the hybrid plants (F-1) were mixoploid. in nature. The chromosome number of many somatic cells was 2n = 26, which was the sum of the chromosome number of the two parents. The chromosome number of other somatic cells was 2n = 38, similar to that of B. napus. The hybrid offspring (F-2) from the selfed hybrid plants (F-1) showed polymorphism. Among the hybrid offspring (F-2) some were nearly matroclinous and fertile, similar to B. napus. some others were intermediate between the two parents and less fertile, and a few were poorly developed and nearly infertile. From the hybrid offspring a few plants with improved seed-oil quality were obtained.展开更多
An efficient genetic transformation system and suitable promoters are essential prerequisites for gene expression studies and genetic engineering in streptomycetes.In this study,firstly,a genetic transformation system...An efficient genetic transformation system and suitable promoters are essential prerequisites for gene expression studies and genetic engineering in streptomycetes.In this study,firstly,a genetic transformation system based on intergeneric conjugation was developed in Streptomyces rimosus M527,a bacterial strain which exhibits strong antagonistic activity against a broad range of plant-pathogenic fungi.Some experimental parameters involved in this procedure were optimized,including the conjugative media,ratio of donor to recipient,heat shock temperature,and incubation time of mixed culture.Under the optimal conditions,a maximal conjugation frequency of 3.05^10-5 per recipie nt was obtai ned.Subseque ntly,based on the above developed and optimized tran sformati on system,the synthetic promoters SPL-21 and SPL-57,a native promoter potrB,and a constitutive promoter permE commonly used for gene expression in streptomycetes were selected and their activity was analyzed using gusA as a reporter gene in S.rimosus M527.Among the four tested promoters,SPL-21 exhibited the strongest expression activity and gave rise to a 2.2-fold increase in p-glucuronidase(GUS)activity compared with the control promoter permE.Promoter SPL-57 showed activity comparable to that of permE.Promoter potrB,which showed the lowest activity,showed a 50%decrease in GUS activity compared with the control permE.The transformation system developed in this study and the tested promotors provide a basis for the further modification of S.rimosus M527.展开更多
In the cross between B. napus with OguCMSOrychophragmus violaceus, pre-fertilizatiocompatibility was observed. An intergeneric hybrid was successfully obtained by usinovary culture. The hybrid status was confirmed by ...In the cross between B. napus with OguCMSOrychophragmus violaceus, pre-fertilizatiocompatibility was observed. An intergeneric hybrid was successfully obtained by usinovary culture. The hybrid status was confirmed by cytology, morphology, fertilityisozyme and miosis analysis. The seed setting rate was 0.0072%. An amphidiploid of thhybrid was also produced by the use of chromosome-doubling method with 0.1% colchicinetreatment. Obtaining this hybrid and its amphidiploid has important theoretical anutilization value.展开更多
A comparative study on the photosynthetic parameters among intergeneric progenies derived from \%Oryza sativa\% L.×\%Sorghum vulgare\% L., its maternal parent Gui 630 and commercial 3\|line hybrid rice Shanyou 63...A comparative study on the photosynthetic parameters among intergeneric progenies derived from \%Oryza sativa\% L.×\%Sorghum vulgare\% L., its maternal parent Gui 630 and commercial 3\|line hybrid rice Shanyou 63 in pot experiment in greenhouse was conducted. The morphological and photosynthetic characters of canopy leaves and chlorophyll fluorescence kinetic parameters including \%F\%\-v/\%F\%\-m, \%F\%\-v/\%F\%\-0, photochemical quenching coefficient and non\|photochemical coefficient of canopy leaves of 3 varieties were measured. The results showed the progeny, Yuanyou 1, derived from an intergeneric cross of rice and sorghum possesses better canopy spatial architecture with thicker, heavier and bigger canopy leaf than its maternal parent Gui 630. Higher photosynthetic rate due to higher chlorophyll content, higher primary energy transformation efficiency, potential of PSII and non\|photochemical quenching coefficient (\%q\%\-E) were also measured in Yuanyou 1. These explain partly why the intergeneric progeny has higher biomass production, and better tolerance to adverse conditions and higher field yields even under stress conditions.展开更多
We succeeded in producing mature seed from a line of Brassica rapa ssp. pekinensis that had been hybridized with Raphanus sativus var. major. Our focus was on dominance of B. rapa ssp. pekinensis;radish (R. sativus va...We succeeded in producing mature seed from a line of Brassica rapa ssp. pekinensis that had been hybridized with Raphanus sativus var. major. Our focus was on dominance of B. rapa ssp. pekinensis;radish (R. sativus var. major) had no influence. Marker tests for similarity showed that the original CR291M-64 x HwiM-2 hybrid was an inbred CR291M-64, rather than a genuine cross;this appears to have resulted from weak self-incompatibility in this strain. The plants from the mature seed bloomed with reddish flowers differently shown up to present. The intergeneric hybrid between Brassica inbred and Raphanus hybrid was very weak in strength compared to the Brassica inbred which was self-pollinated even though the cause of the weak was not identified. The hybrids between Brassica hybrid, dominant and elite recessive, and Raphanus can be developed in large quantities using mature hybrid seed without resorting to ovule culture techniques.展开更多
To detect the intergeneric hybridization between the oyster Crassostrea angulata and Saccostrea cucullata coexisting along the southern coast of China, reciprocal crosses were conducted between the two species. Barrie...To detect the intergeneric hybridization between the oyster Crassostrea angulata and Saccostrea cucullata coexisting along the southern coast of China, reciprocal crosses were conducted between the two species. Barriers for sperm recognizing, binding, penetrating the egg, and forming the pronucleus were detected by fluorescence staining. From the results, although fertilization success was observed in hybrid crosses, the overall fertilization rate was lower than that of intraspecific crosses. A large number of hybrid larvae died at 6–8 d after hatching, and those survived could not complete metamorphosis. C. angulata ♀× S. cucullata ♂ larvae had a growth rate similar to that of the maternal species, whereas S. cucullata ♀× C. angulata ♂ larvae grew the slowest among all crosses. Molecular genetics analysis revealed that hybrid progeny were amphimixis hybrids. This study demonstrated that hybrid embryos generated by crossing C. angulata and S. cucullata could develop normally to the larval state, but could not complete metamorphosis and then develop to the spat stage. Thus, there is a post-reproductive isolation between C. angulata and S. cucullata.展开更多
: Electrically induced protoplast fusion was used to produce somatic hybrids between Brassica napus L. and Sinapis alba L. Seven hybrids were obtained and verified by the simple sequence repeat and cleaved amplified p...: Electrically induced protoplast fusion was used to produce somatic hybrids between Brassica napus L. and Sinapis alba L. Seven hybrids were obtained and verified by the simple sequence repeat and cleaved amplified polymorphic sequence analysis of the gene fael, indicating that the characteristic bands from S. alba were present in the hybrids. The hybridity was also confirmed by chromosome number counting because the hybrids possessed 62 chromosomes, corresponding to the sum of fusion-parent chromosomes. Chromosome pairing at meiosis was predominantly normal, which led to high pollen fertility, ranging from 66% to 77%. All hybrids were grown to full maturity and could be fertilized and set seed after self-pollination or back-crosses with B. napus. The morphology of the hybrids resembled characteristics from both parental species. An analysis of the fatty acid composition in the seeds of F1 plants was conducted and the seeds were found to contain different amounts of erucic acid, ranging from 11.0% to 52.1%.展开更多
Haynaldia villosa possesses a lot of important agronomic traits and has been a powerful gene resource for wheat improvement. However, only several wheat-H, villosa translocation lines have been reported so far. In thi...Haynaldia villosa possesses a lot of important agronomic traits and has been a powerful gene resource for wheat improvement. However, only several wheat-H, villosa translocation lines have been reported so far. In this study, we attempted to develop an efficient method for inducing wheat-H, villosa chromosomal translocations. Triticum durum- Haynaldia villosa amphiploid pollen treated with 1 200 rad ^60Co-y-rays was pollinated to Triticum aestivum cv. ＇Chinese Spring＇. Ninety-eight intergeneric translocated chromosomes between T. durum and H. villosa were detected by genomic in situ hybridization in 44 of 61 M1 plants, indicating a translocation occurrence frequency of 72.1%; much higher than ever reported. There were 26, 62 and 10 translocated chromosomes involving whole arm translocations, terminal translocations, and intercarlary translocations, respectively. Of the total 108 breakage-fusion events, 79 involved interstitial regions and 29 involved centric regions. The ratio of small segment terminal translocations （W.W-V） was much higher than that of large segment terminal translocations （W-V.V）. All of the M1 plants were self-sterile, and their backcross progeny was all obtained with ＇Chinese Spring＇ as pollen donors. Transmission analysis showed that most of the translocations were transmittable. This study provides a new strategy for rapid mass production of wheat-alien chromosomal translocations, especially terminal translocations that will be more significant for wheat improvement.展开更多
Taxodiorneria peizhongii Z. J. Ye, J. J. Zhang et S. H. Pan was regarded as a new Intergenerlc hybrid between Taxodlum mucronatum Tenore （as the female donor） and Cryptomeria fortunei Hoolbrenk ex Otto et Dletr （as...Taxodiorneria peizhongii Z. J. Ye, J. J. Zhang et S. H. Pan was regarded as a new Intergenerlc hybrid between Taxodlum mucronatum Tenore （as the female donor） and Cryptomeria fortunei Hoolbrenk ex Otto et Dletr （as the male donor）. To confirm the authenticity of the intergeneric hybrid, we analyzed the rbcL gene and the Internal transcribed spacer （ITS） of 26S-18S ribosomal RNA gene of the three species using polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） and arbitrarily primed PCR （AP-PCR）, and ob- tained the following results：i） Taxodiomeria peizhongii had the same RFLP maps of the rbcL gene and the ITS as Taxodlum mucronatum, but was different from C. fortunei; II） a 311-bp PCR amplification product was obtained In C. fortunei by AP-PCR of ITS, but was not found in Taxodiomeria peizhongii. Our results have demonstrated that C. fortunei did not provide any genome for Taxodiomeria peizhongii, Implying that T. peizhongii Is not an Intergenerlc hybrid between the two species.展开更多
Through embryo culture, intergeneric hybrids were produced between common wheat,Triticum aestivum cv. Chinese Spring (CS) (2n= 6x = 42, AABBDD) and crested wheatgrass,Agropyron desertorum (2n =4x =28, PPPP) for the fi...Through embryo culture, intergeneric hybrids were produced between common wheat,Triticum aestivum cv. Chinese Spring (CS) (2n= 6x = 42, AABBDD) and crested wheatgrass,Agropyron desertorum (2n =4x =28, PPPP) for the first time. Their F_2 and BC_1 seeds havealso been successfully obtained by selfing and backcrossing with wheat in F_1 hybrids. Theseedlings of all F_1 hybrids tended to resemble their female parent, but they had more tillers,and their spike characteristics were between their parents. Average meiotic chromosomepairing at MI of F_1 hybrids was: 6.62Ⅰ+ 8.20RingⅡ+ 4.16RodⅡ+0.57Ⅲ+ 0.35Ⅳ+0.06Ⅴ+0.03Ⅵ. The successful experience of hybridization of common wheat with A. desertorum,the reason for the high level of chromosome pairing and self-fertility in the F_1 hybrids werediscussed. The F_2 and BC_1 seeds obtained in F_1 hybrids are of great importance to theory andpractice.展开更多
Introduction In order to improve cultivated wheat, a lot of intergeneric hybrids between wheat and its relatives, such as Aegilops, Secale, Haynaldia, Hordeum, Thinopyrum, Pseudoroegneria, Elytrigia, Elymus and Leymus...Introduction In order to improve cultivated wheat, a lot of intergeneric hybrids between wheat and its relatives, such as Aegilops, Secale, Haynaldia, Hordeum, Thinopyrum, Pseudoroegneria, Elytrigia, Elymus and Leymus have been obtained.展开更多
Intergenerational inheritance of stress memory plays a crucial role in plant adaptation to environmental changes,particularly in the context of spaceflight,where plants may serve as a food source for humans on long-du...Intergenerational inheritance of stress memory plays a crucial role in plant adaptation to environmental changes,particularly in the context of spaceflight,where plants may serve as a food source for humans on long-duration missions.However,the intergenerational genetic effects of spaceflight-induced stress memory in plants remain unclear.In this study,we assessed the cross-generational genetic effects of spaceflight stress memory using the rice mutant B10,identified during the SJ-10 return satellite mission.Our results showed that the oxidative stress effects induced by spaceflight persisted until the M5 generation in rice.We found that the rice genome remained unstable post-spaceflight,leading to alterations in genome methylation levels.Additionally,we observed significant changes in the methylation levels of transposons,suggesting their involvement in the intergenerational inheritance of spaceflight-induced stress memory.Furthermore,we identified thousands of differentially expressed genes(DEGs)and differentially alternatively spliced(DAS)genes induced by spaceflight stress memory across multiple rice generations.Notably,differentially methylated cytosines were more abundant in non-expressed genes than in DEGs or DAS genes.A substantial number of DEGs and DASs related to oxidative stress were identified,primarily involved in the generation and scavenging of reactive oxygen species.This study also presented report on the response of alternative splicing events in rice to spaceflight stress.Moreover,our findings revealed that genome methylation was associated with gene expression but not with DAS.In conclusion,our study provides comprehensive insights into the intergenerational inheritance of spaceflight-induced stress in rice and may contribute to uncovering novel mechanisms of oxidative stress-induced genomic instability and epigenetic regulation in plant stress inheritance.展开更多
This study explores the impact of intergenerational differences on farmers' terrace abandonment in response to increasing intergenerational differentiation among rural households and the practical issue of terrace...This study explores the impact of intergenerational differences on farmers' terrace abandonment in response to increasing intergenerational differentiation among rural households and the practical issue of terrace abandonment. Logit and Tobit models are employed to conduct empirical analysis and it is found that terrace abandonment increases sequentially among the new, middle, and old generations, confirming that intergenerational differences significantly influence whether farmers abandon terraces and the terrace abandonment scale. Village characteristics and government subsidies significantly influence farmers' terrace abandonment. An increase in the number of migrant workers in the village increases terrace abandonment among new and middle generation farmers, whereas an increase in the distance from the village to the county significantly increases terrace abandonment among old generation farmers. An increase in the village's total population significantly reduces terrace abandonment among new generation farmers. An increase in government subsidies significantly reduces terrace abandonment among middle and old generation farmers. The impact of intergenerational differences on terrace abandonment is more pronounced in low-altitude areas. To reduce terrace abandonment, it is necessary to promote terrace transfer, develop characteristic agriculture, improve terrace farming subsidies, and propose targeted strategies for the different generations of farmers.展开更多
Based on two waves of CHARLS data,this paper uses descriptive statistics and a binary logistic regression estimation model to analyze the effect of age on the intergenerational economic support for the rural elderly w...Based on two waves of CHARLS data,this paper uses descriptive statistics and a binary logistic regression estimation model to analyze the effect of age on the intergenerational economic support for the rural elderly within the framework of three-generation lineal group families.The study found that the diffusion effect of age on the intergenerational economic support for the rural elderly still existed when using a five-year age group model as the measure.In the distribution of intergenerational economic support for the rural elderly by age group,there was a notable decline in economic support from the filial generation for those aged 85 and above.For the age group of 85 and above,it was the grandchild generation that gradually increased its economic support,the result of a form of intergenerational relay for the care of the elderly.Comparison of the two waves of data reveals that familism still exhibits a strong resilience and is behind the intergenerational cooperation in Chinese rural families.The culture of filial piety and respect for elders,which reflects China’s national characteristics as well as contemporary values,should continue to be promoted.To achieve this,it is necessary to maintain the supportive function of family-based care for the rural elderly through family-friendly policies and the systematic improvement of the current multi-tiered policies for the care of the rural elderly.展开更多
Jovani et al’s study contributes important evidence linking childhood trauma(CT)and parental socialization with at-risk mental state(ARMS)in non-clinical adolescents,demonstrating the mediating role of low levels of ...Jovani et al’s study contributes important evidence linking childhood trauma(CT)and parental socialization with at-risk mental state(ARMS)in non-clinical adolescents,demonstrating the mediating role of low levels of parental affection and communication in this relationship.This letter commends the study’s strengths while also identifying key issues that warrant further attention,including the limitations of cross-sectional design,potential perceptual biases,conceptual overlap between CT and parenting,and limited cultural generalizability.We advocate for longitudinal,culturally sensitive,and multi-informant approaches to further refine ARMS risk models,strengthen theoretical distinctions between CT and parenting,and inform targeted prevention strategies across diverse populations.We also extend the discussion by highlighting promising directions for future research.展开更多
Rice production is crucial for food security in China,and its relationship with rural labor migration has been studied extensively.Labor migration in rural China has taken new forms in recent years.There has been a di...Rice production is crucial for food security in China,and its relationship with rural labor migration has been studied extensively.Labor migration in rural China has taken new forms in recent years.There has been a discernible trend wherein adult children have started migrating to cities while their elderly parents return to villages to re-engage in on-farm work.The phenomenon has notably shaped the intergenerational division of labor(IDL)within households.However,it remains to be seen how farmers adjust their rice production systems in response to the IDL.The age of 60 years for employment injury insurance is the eligibility threshold for off-farm employment and is used to obtain a source of exogenous variation in the IDL.Based on a representative household survey of 1,752 rice farmers in the Hubei Province of Central China,our fuzzy regression discontinuity analysis reveals that farmers in IDL households are more likely to adopt ratoon rice(RR)than single cropping rice(SR)or double cropping rice(DR).The effect of the IDL varies under different levels of operational scales and specialized agricultural service availability.Further analysis suggests that farmers’arrangements are associated with two potential mechanisms of downward intergenerational transfer.Monetary transfer for urban housing purchases increases RR in IDL households,and time transfer for intergenerational childcare significantly promotes SR in IDL households.This study enhances the understanding of the relationship between rural labor migration and rice production in China,providing a reference for adjusting rice production systems to ensure food security.展开更多
Tributyltin(TBT),a common organotin environmental pollutant,may pose a threat to human development during critical early-life periods.We aimed to assess the neurodevelopmental intergenerational toxicity of early-life ...Tributyltin(TBT),a common organotin environmental pollutant,may pose a threat to human development during critical early-life periods.We aimed to assess the neurodevelopmental intergenerational toxicity of early-life exposure to TBT and the protective effect of DNA methyl donor folic acid(FA).Specifically,after early-life exposure(1–21 days postfertilization,dpf)to TBT(0,1,10 and 100 ng/L),zebrafish(Danio rerio)were cultured in clean medium until sexual maturity.The exposed females were mated with unexposed males to produce embryos(F1).The F1 generation were cultured(4–120 hours post-fertilization,hpf)with and without 1 mmol/L FA.The neurotoxic effects of early-life TBT exposure for zebrafish and their offspring(F1)were significantly enhanced anxiety and reduced aggression,decreased gene expression of DNA methyltransferase in the brain and increased serotonin levels in the body.Moreover,the intergenerational neurodevelopmental toxicity,as manifested in the F1 generation,was attenuated by FA supplementation.In summary,early-life TBT exposure led to intergenerational neurodevelopmental deficits in zebrafish,and DNA methyl donors had a protective effect on F1 neurodevelopment,which can inform the prevention and treatment of intergenerational neurotoxicity due to organotin pollutants.展开更多
Research Background: Psychological stressors leading to poor mental health outcomes accumulate throughout the migration process. The impact of a parent or caregiver’s posttraumatic stress on non-traumatized children ...Research Background: Psychological stressors leading to poor mental health outcomes accumulate throughout the migration process. The impact of a parent or caregiver’s posttraumatic stress on non-traumatized children is significant and may lead to adverse development and mental health outcomes. Research Objectives: The objective of this review is to explore both the consequences of parental trauma transmission on descendants’ psychological adjustment and well-being, and the mechanisms through which trauma has been transmitted among im/migrant populations. Methods: Criteria outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement guided this systemic review. The questions guiding this review are: (a) What are the consequences of parental trauma transmission on the psychological adjustment and well-being of im/migrant offspring? And (b) What are the psychosocial mechanisms of trauma and resilience transmission among im/migrant populations? Each potential study was assessed based on relevance to the review question(s). Results: Parental trauma can lead to adverse mental health outcomes among descendants including increased internalizing and externalizing problems, the adoption of coping behaviors and worldviews, and worsening school performance. Mechanisms that influence trauma transmission include parental trauma symptom severity, the parent-child dyad, social learning, and family stressors. Pathways of resilience exist across socioecological levels to include individual resilience such as coping skills and meaning making, family resilience, structural protective factors, and social and cultural protective factors. Conclusions: Despite the prevalence of traumatic events throughout the migration process, im/migrant families display strong levels of resilience. Mental health services and providers should incorporate a strength-based approach in designing interventions that are culturally responsive and take into accounts the broader ecological contexts in which im/migrant families live.展开更多
文摘The intergeneric hybridization between Brassica napus L. cv. oro and Matthiola incana (L.) R. Br. was carried out to study the phytogenetic peculiarities of the hybrid plants. In order to improve the oil quality of rape seed, ovaries of B. napus pollinated with pollen of M. incana, were cut off and inoculated onto MS media supplemented with various plant hormones at the 7th day after pollination. Two mature embryos were obtained from 750 pollinated ovaries cultured in vitro. The percentage of seed set was 0.26%. The mature embryos were transferred onto the MS media supplemented with 2.0 mg/L 6-BA + 0.1 mg/L NAA, and a compound bud was produced later. The compound bud was then cut into a number of single buds, which were transferred onto fresh media. Twenty-two plantlets in vitro were developed from the above single buds. The hybrid plants (F-1) were basically intermediate between the two parents in many,characters with a few showing hybrid vigor. The fertility of hybrid plants (F-1) was poor. Cytological studies revealed that the hybrid plants (F-1) were mixoploid. in nature. The chromosome number of many somatic cells was 2n = 26, which was the sum of the chromosome number of the two parents. The chromosome number of other somatic cells was 2n = 38, similar to that of B. napus. The hybrid offspring (F-2) from the selfed hybrid plants (F-1) showed polymorphism. Among the hybrid offspring (F-2) some were nearly matroclinous and fertile, similar to B. napus. some others were intermediate between the two parents and less fertile, and a few were poorly developed and nearly infertile. From the hybrid offspring a few plants with improved seed-oil quality were obtained.
基金Project supported by the National Natural Science Foundation of China(Nos.31772213 and 31972320)the Excellent Youth Fund of Zhejiang Province,China(No.LR17C140002)
文摘An efficient genetic transformation system and suitable promoters are essential prerequisites for gene expression studies and genetic engineering in streptomycetes.In this study,firstly,a genetic transformation system based on intergeneric conjugation was developed in Streptomyces rimosus M527,a bacterial strain which exhibits strong antagonistic activity against a broad range of plant-pathogenic fungi.Some experimental parameters involved in this procedure were optimized,including the conjugative media,ratio of donor to recipient,heat shock temperature,and incubation time of mixed culture.Under the optimal conditions,a maximal conjugation frequency of 3.05^10-5 per recipie nt was obtai ned.Subseque ntly,based on the above developed and optimized tran sformati on system,the synthetic promoters SPL-21 and SPL-57,a native promoter potrB,and a constitutive promoter permE commonly used for gene expression in streptomycetes were selected and their activity was analyzed using gusA as a reporter gene in S.rimosus M527.Among the four tested promoters,SPL-21 exhibited the strongest expression activity and gave rise to a 2.2-fold increase in p-glucuronidase(GUS)activity compared with the control promoter permE.Promoter SPL-57 showed activity comparable to that of permE.Promoter potrB,which showed the lowest activity,showed a 50%decrease in GUS activity compared with the control permE.The transformation system developed in this study and the tested promotors provide a basis for the further modification of S.rimosus M527.
基金supported by the National Natura1 Science Foundation of China(39470457) the Ninth Five-Year Major Program of China.
文摘In the cross between B. napus with OguCMSOrychophragmus violaceus, pre-fertilizatiocompatibility was observed. An intergeneric hybrid was successfully obtained by usinovary culture. The hybrid status was confirmed by cytology, morphology, fertilityisozyme and miosis analysis. The seed setting rate was 0.0072%. An amphidiploid of thhybrid was also produced by the use of chromosome-doubling method with 0.1% colchicinetreatment. Obtaining this hybrid and its amphidiploid has important theoretical anutilization value.
文摘A comparative study on the photosynthetic parameters among intergeneric progenies derived from \%Oryza sativa\% L.×\%Sorghum vulgare\% L., its maternal parent Gui 630 and commercial 3\|line hybrid rice Shanyou 63 in pot experiment in greenhouse was conducted. The morphological and photosynthetic characters of canopy leaves and chlorophyll fluorescence kinetic parameters including \%F\%\-v/\%F\%\-m, \%F\%\-v/\%F\%\-0, photochemical quenching coefficient and non\|photochemical coefficient of canopy leaves of 3 varieties were measured. The results showed the progeny, Yuanyou 1, derived from an intergeneric cross of rice and sorghum possesses better canopy spatial architecture with thicker, heavier and bigger canopy leaf than its maternal parent Gui 630. Higher photosynthetic rate due to higher chlorophyll content, higher primary energy transformation efficiency, potential of PSII and non\|photochemical quenching coefficient (\%q\%\-E) were also measured in Yuanyou 1. These explain partly why the intergeneric progeny has higher biomass production, and better tolerance to adverse conditions and higher field yields even under stress conditions.
文摘We succeeded in producing mature seed from a line of Brassica rapa ssp. pekinensis that had been hybridized with Raphanus sativus var. major. Our focus was on dominance of B. rapa ssp. pekinensis;radish (R. sativus var. major) had no influence. Marker tests for similarity showed that the original CR291M-64 x HwiM-2 hybrid was an inbred CR291M-64, rather than a genuine cross;this appears to have resulted from weak self-incompatibility in this strain. The plants from the mature seed bloomed with reddish flowers differently shown up to present. The intergeneric hybrid between Brassica inbred and Raphanus hybrid was very weak in strength compared to the Brassica inbred which was self-pollinated even though the cause of the weak was not identified. The hybrids between Brassica hybrid, dominant and elite recessive, and Raphanus can be developed in large quantities using mature hybrid seed without resorting to ovule culture techniques.
文摘To detect the intergeneric hybridization between the oyster Crassostrea angulata and Saccostrea cucullata coexisting along the southern coast of China, reciprocal crosses were conducted between the two species. Barriers for sperm recognizing, binding, penetrating the egg, and forming the pronucleus were detected by fluorescence staining. From the results, although fertilization success was observed in hybrid crosses, the overall fertilization rate was lower than that of intraspecific crosses. A large number of hybrid larvae died at 6–8 d after hatching, and those survived could not complete metamorphosis. C. angulata ♀× S. cucullata ♂ larvae had a growth rate similar to that of the maternal species, whereas S. cucullata ♀× C. angulata ♂ larvae grew the slowest among all crosses. Molecular genetics analysis revealed that hybrid progeny were amphimixis hybrids. This study demonstrated that hybrid embryos generated by crossing C. angulata and S. cucullata could develop normally to the larval state, but could not complete metamorphosis and then develop to the spat stage. Thus, there is a post-reproductive isolation between C. angulata and S. cucullata.
文摘: Electrically induced protoplast fusion was used to produce somatic hybrids between Brassica napus L. and Sinapis alba L. Seven hybrids were obtained and verified by the simple sequence repeat and cleaved amplified polymorphic sequence analysis of the gene fael, indicating that the characteristic bands from S. alba were present in the hybrids. The hybridity was also confirmed by chromosome number counting because the hybrids possessed 62 chromosomes, corresponding to the sum of fusion-parent chromosomes. Chromosome pairing at meiosis was predominantly normal, which led to high pollen fertility, ranging from 66% to 77%. All hybrids were grown to full maturity and could be fertilized and set seed after self-pollination or back-crosses with B. napus. The morphology of the hybrids resembled characteristics from both parental species. An analysis of the fatty acid composition in the seeds of F1 plants was conducted and the seeds were found to contain different amounts of erucic acid, ranging from 11.0% to 52.1%.
基金Supported by the National Natural Science Foundation of China(30270827)the Program for Changjiang Scholars and Innovative Research in Universities(10418).
文摘Haynaldia villosa possesses a lot of important agronomic traits and has been a powerful gene resource for wheat improvement. However, only several wheat-H, villosa translocation lines have been reported so far. In this study, we attempted to develop an efficient method for inducing wheat-H, villosa chromosomal translocations. Triticum durum- Haynaldia villosa amphiploid pollen treated with 1 200 rad ^60Co-y-rays was pollinated to Triticum aestivum cv. ＇Chinese Spring＇. Ninety-eight intergeneric translocated chromosomes between T. durum and H. villosa were detected by genomic in situ hybridization in 44 of 61 M1 plants, indicating a translocation occurrence frequency of 72.1%; much higher than ever reported. There were 26, 62 and 10 translocated chromosomes involving whole arm translocations, terminal translocations, and intercarlary translocations, respectively. Of the total 108 breakage-fusion events, 79 involved interstitial regions and 29 involved centric regions. The ratio of small segment terminal translocations （W.W-V） was much higher than that of large segment terminal translocations （W-V.V）. All of the M1 plants were self-sterile, and their backcross progeny was all obtained with ＇Chinese Spring＇ as pollen donors. Transmission analysis showed that most of the translocations were transmittable. This study provides a new strategy for rapid mass production of wheat-alien chromosomal translocations, especially terminal translocations that will be more significant for wheat improvement.
基金National Natural Science Foundation of China （39970061）.
文摘Taxodiorneria peizhongii Z. J. Ye, J. J. Zhang et S. H. Pan was regarded as a new Intergenerlc hybrid between Taxodlum mucronatum Tenore （as the female donor） and Cryptomeria fortunei Hoolbrenk ex Otto et Dletr （as the male donor）. To confirm the authenticity of the intergeneric hybrid, we analyzed the rbcL gene and the Internal transcribed spacer （ITS） of 26S-18S ribosomal RNA gene of the three species using polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） and arbitrarily primed PCR （AP-PCR）, and ob- tained the following results：i） Taxodiomeria peizhongii had the same RFLP maps of the rbcL gene and the ITS as Taxodlum mucronatum, but was different from C. fortunei; II） a 311-bp PCR amplification product was obtained In C. fortunei by AP-PCR of ITS, but was not found in Taxodiomeria peizhongii. Our results have demonstrated that C. fortunei did not provide any genome for Taxodiomeria peizhongii, Implying that T. peizhongii Is not an Intergenerlc hybrid between the two species.
文摘Through embryo culture, intergeneric hybrids were produced between common wheat,Triticum aestivum cv. Chinese Spring (CS) (2n= 6x = 42, AABBDD) and crested wheatgrass,Agropyron desertorum (2n =4x =28, PPPP) for the first time. Their F_2 and BC_1 seeds havealso been successfully obtained by selfing and backcrossing with wheat in F_1 hybrids. Theseedlings of all F_1 hybrids tended to resemble their female parent, but they had more tillers,and their spike characteristics were between their parents. Average meiotic chromosomepairing at MI of F_1 hybrids was: 6.62Ⅰ+ 8.20RingⅡ+ 4.16RodⅡ+0.57Ⅲ+ 0.35Ⅳ+0.06Ⅴ+0.03Ⅵ. The successful experience of hybridization of common wheat with A. desertorum,the reason for the high level of chromosome pairing and self-fertility in the F_1 hybrids werediscussed. The F_2 and BC_1 seeds obtained in F_1 hybrids are of great importance to theory andpractice.
文摘Introduction In order to improve cultivated wheat, a lot of intergeneric hybrids between wheat and its relatives, such as Aegilops, Secale, Haynaldia, Hordeum, Thinopyrum, Pseudoroegneria, Elytrigia, Elymus and Leymus have been obtained.
基金supported by the Natural Science Foundation of Chongqing,China(Grant No.CSTB2024NSCQ-MSX0462)the Postdoctoral Fellowship Program of CPSF,China(Grant No.GZC20242211)+1 种基金the Heilongjiang Touyan Team,China(Grant No.HITTY-20190034)the Project of the Aerospace Science and Technology Collaborative Innovation Center,China(Grant No.BSAUEA5740600223).
文摘Intergenerational inheritance of stress memory plays a crucial role in plant adaptation to environmental changes,particularly in the context of spaceflight,where plants may serve as a food source for humans on long-duration missions.However,the intergenerational genetic effects of spaceflight-induced stress memory in plants remain unclear.In this study,we assessed the cross-generational genetic effects of spaceflight stress memory using the rice mutant B10,identified during the SJ-10 return satellite mission.Our results showed that the oxidative stress effects induced by spaceflight persisted until the M5 generation in rice.We found that the rice genome remained unstable post-spaceflight,leading to alterations in genome methylation levels.Additionally,we observed significant changes in the methylation levels of transposons,suggesting their involvement in the intergenerational inheritance of spaceflight-induced stress memory.Furthermore,we identified thousands of differentially expressed genes(DEGs)and differentially alternatively spliced(DAS)genes induced by spaceflight stress memory across multiple rice generations.Notably,differentially methylated cytosines were more abundant in non-expressed genes than in DEGs or DAS genes.A substantial number of DEGs and DASs related to oxidative stress were identified,primarily involved in the generation and scavenging of reactive oxygen species.This study also presented report on the response of alternative splicing events in rice to spaceflight stress.Moreover,our findings revealed that genome methylation was associated with gene expression but not with DAS.In conclusion,our study provides comprehensive insights into the intergenerational inheritance of spaceflight-induced stress in rice and may contribute to uncovering novel mechanisms of oxidative stress-induced genomic instability and epigenetic regulation in plant stress inheritance.
基金Key Program of National Natural Science Foundation of China,No.41930757National Natural Science Foundation of China,No.42371285。
文摘This study explores the impact of intergenerational differences on farmers' terrace abandonment in response to increasing intergenerational differentiation among rural households and the practical issue of terrace abandonment. Logit and Tobit models are employed to conduct empirical analysis and it is found that terrace abandonment increases sequentially among the new, middle, and old generations, confirming that intergenerational differences significantly influence whether farmers abandon terraces and the terrace abandonment scale. Village characteristics and government subsidies significantly influence farmers' terrace abandonment. An increase in the number of migrant workers in the village increases terrace abandonment among new and middle generation farmers, whereas an increase in the distance from the village to the county significantly increases terrace abandonment among old generation farmers. An increase in the village's total population significantly reduces terrace abandonment among new generation farmers. An increase in government subsidies significantly reduces terrace abandonment among middle and old generation farmers. The impact of intergenerational differences on terrace abandonment is more pronounced in low-altitude areas. To reduce terrace abandonment, it is necessary to promote terrace transfer, develop characteristic agriculture, improve terrace farming subsidies, and propose targeted strategies for the different generations of farmers.
基金the National Social Science Foundation of China’s general project“Research on the Enhancement of the Elderly Care Support of Rural Families under the Changing Intergenerational Relations”(Project No.:21BRK028)in 2021.
文摘Based on two waves of CHARLS data,this paper uses descriptive statistics and a binary logistic regression estimation model to analyze the effect of age on the intergenerational economic support for the rural elderly within the framework of three-generation lineal group families.The study found that the diffusion effect of age on the intergenerational economic support for the rural elderly still existed when using a five-year age group model as the measure.In the distribution of intergenerational economic support for the rural elderly by age group,there was a notable decline in economic support from the filial generation for those aged 85 and above.For the age group of 85 and above,it was the grandchild generation that gradually increased its economic support,the result of a form of intergenerational relay for the care of the elderly.Comparison of the two waves of data reveals that familism still exhibits a strong resilience and is behind the intergenerational cooperation in Chinese rural families.The culture of filial piety and respect for elders,which reflects China’s national characteristics as well as contemporary values,should continue to be promoted.To achieve this,it is necessary to maintain the supportive function of family-based care for the rural elderly through family-friendly policies and the systematic improvement of the current multi-tiered policies for the care of the rural elderly.
文摘Jovani et al’s study contributes important evidence linking childhood trauma(CT)and parental socialization with at-risk mental state(ARMS)in non-clinical adolescents,demonstrating the mediating role of low levels of parental affection and communication in this relationship.This letter commends the study’s strengths while also identifying key issues that warrant further attention,including the limitations of cross-sectional design,potential perceptual biases,conceptual overlap between CT and parenting,and limited cultural generalizability.We advocate for longitudinal,culturally sensitive,and multi-informant approaches to further refine ARMS risk models,strengthen theoretical distinctions between CT and parenting,and inform targeted prevention strategies across diverse populations.We also extend the discussion by highlighting promising directions for future research.
基金supported by the National Natural Science Foundation of China(42207529)the China Postdoctoral Science Foundation(2022M721289).
文摘Rice production is crucial for food security in China,and its relationship with rural labor migration has been studied extensively.Labor migration in rural China has taken new forms in recent years.There has been a discernible trend wherein adult children have started migrating to cities while their elderly parents return to villages to re-engage in on-farm work.The phenomenon has notably shaped the intergenerational division of labor(IDL)within households.However,it remains to be seen how farmers adjust their rice production systems in response to the IDL.The age of 60 years for employment injury insurance is the eligibility threshold for off-farm employment and is used to obtain a source of exogenous variation in the IDL.Based on a representative household survey of 1,752 rice farmers in the Hubei Province of Central China,our fuzzy regression discontinuity analysis reveals that farmers in IDL households are more likely to adopt ratoon rice(RR)than single cropping rice(SR)or double cropping rice(DR).The effect of the IDL varies under different levels of operational scales and specialized agricultural service availability.Further analysis suggests that farmers’arrangements are associated with two potential mechanisms of downward intergenerational transfer.Monetary transfer for urban housing purchases increases RR in IDL households,and time transfer for intergenerational childcare significantly promotes SR in IDL households.This study enhances the understanding of the relationship between rural labor migration and rice production in China,providing a reference for adjusting rice production systems to ensure food security.
基金supported by the National Natural Science Foundation of China (Nos.32071301,31971234 and 42177411)the Natural Science Foundation of Fujian Province,China (No.2020J01027)。
文摘Tributyltin(TBT),a common organotin environmental pollutant,may pose a threat to human development during critical early-life periods.We aimed to assess the neurodevelopmental intergenerational toxicity of early-life exposure to TBT and the protective effect of DNA methyl donor folic acid(FA).Specifically,after early-life exposure(1–21 days postfertilization,dpf)to TBT(0,1,10 and 100 ng/L),zebrafish(Danio rerio)were cultured in clean medium until sexual maturity.The exposed females were mated with unexposed males to produce embryos(F1).The F1 generation were cultured(4–120 hours post-fertilization,hpf)with and without 1 mmol/L FA.The neurotoxic effects of early-life TBT exposure for zebrafish and their offspring(F1)were significantly enhanced anxiety and reduced aggression,decreased gene expression of DNA methyltransferase in the brain and increased serotonin levels in the body.Moreover,the intergenerational neurodevelopmental toxicity,as manifested in the F1 generation,was attenuated by FA supplementation.In summary,early-life TBT exposure led to intergenerational neurodevelopmental deficits in zebrafish,and DNA methyl donors had a protective effect on F1 neurodevelopment,which can inform the prevention and treatment of intergenerational neurotoxicity due to organotin pollutants.
文摘Research Background: Psychological stressors leading to poor mental health outcomes accumulate throughout the migration process. The impact of a parent or caregiver’s posttraumatic stress on non-traumatized children is significant and may lead to adverse development and mental health outcomes. Research Objectives: The objective of this review is to explore both the consequences of parental trauma transmission on descendants’ psychological adjustment and well-being, and the mechanisms through which trauma has been transmitted among im/migrant populations. Methods: Criteria outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement guided this systemic review. The questions guiding this review are: (a) What are the consequences of parental trauma transmission on the psychological adjustment and well-being of im/migrant offspring? And (b) What are the psychosocial mechanisms of trauma and resilience transmission among im/migrant populations? Each potential study was assessed based on relevance to the review question(s). Results: Parental trauma can lead to adverse mental health outcomes among descendants including increased internalizing and externalizing problems, the adoption of coping behaviors and worldviews, and worsening school performance. Mechanisms that influence trauma transmission include parental trauma symptom severity, the parent-child dyad, social learning, and family stressors. Pathways of resilience exist across socioecological levels to include individual resilience such as coping skills and meaning making, family resilience, structural protective factors, and social and cultural protective factors. Conclusions: Despite the prevalence of traumatic events throughout the migration process, im/migrant families display strong levels of resilience. Mental health services and providers should incorporate a strength-based approach in designing interventions that are culturally responsive and take into accounts the broader ecological contexts in which im/migrant families live.
