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BACKGROUND: Heart failure (HF) remains a major cause of mortality, hospitalisations, and poor quality of life. The mortality and readmission rate of HF patients after discharge are still high due to poor self-care and adherence, or inability to detect signs of deterioration. Telehealth programs may benefit a broad range of patients and reduce the suffering from HF. We aimed to investigate the impact of a 12-week telehealth program on outcomes among discharged patients with HF. METHODS: Study population was consisted of 425 patients discharged between Jan 2020 to Aug 2020. All enrolled participants were diagnosed as HF and underwent standard treatments. At discharge, they were randomised into the telehealth or control group. The intervention was based on telephone support biweekly. After 12-week follow-up, patients' outcomes including mortality, readmission, disease condition, adherence, self-care behaviours, and mental health were compared between the groups. RESULTS: The telehealth program significantly improved the HF symptoms in patients (p < 0.001). Patients in telehealth group showed better adherence compared to control (p = 0.002). Moreover, the intervention enhanced patients' self-care skills, indicated by the increased ratio of individuals knowing how to evaluate the cardiac function (p = 0.009) and purchasing medicines (p = 0.03). In addition, the telehealth program significantly improved the mental health status of patients (p = 0.03). CONCLUSION: The telehealth program is beneficial for improving HF symptoms, adherence, self-care skills and mental health status of discharged patients and support the future use of this program to manage patients and reduce the burden attributed to the condition.
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Insuficiencia Cardíaca , Telemedicina , Humanos , Alta del Paciente , Calidad de Vida , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/terapia , HospitalizaciónRESUMEN
To explore the effect of the interdisciplinary chronic disease management (CDM) model on patients with hypertension. In this intervention study, the subjects were divided into CDM and control groups. Blood pressure control was monitored in both groups. After 1 year of follow-up, the endpoint events of patients and their knowledge, confidence, and behavior in response to the disease were assessed. When compared with the control group, patients in the CDM group obtained higher scores for self-perception and management assessment, and their blood pressure control was also better after discharge. The quality of life and the satisfaction level of patients in the control group were lower than those in the CDM group, while the unplanned readmission rate, incidence of complications, and the average length of hospital stay in the control group were higher than those in the CDM group. CDM model was beneficial to blood pressure control in hypertensive patients. It had also improved the quality of life and the satisfaction level of the hypertensive patients. Our study highlights the importance of the CDM model in the prognosis of hypertensive patients.
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Hipertensión , Automanejo , Enfermedad Crónica , Estudios de Cohortes , Manejo de la Enfermedad , Humanos , Hipertensión/terapia , Calidad de VidaRESUMEN
Hybridization between Xian/indica (XI) and Geng/japonica (GJ) rice combined with utilization of plant ideotypes has greatly contributed to yield improvements in modern GJ rice in China over the past 50 years. To explore the genomic basis of improved yield and disease resistance in GJ rice, we conducted a large-scale genomic landscape analysis of 816 elite GJ cultivars representing multiple eras of germplasm from China. We detected consistently increasing introgressions from three XI subpopulations into GJ cultivars since the 1980s and found that the XI genome introgressions significantly increased the grain number per panicle (GN) and decreased the panicle number per plant. This contributed to the improvement of plant type during modern breeding, changing multi-tiller plants to moderate tiller plants with a large panicle size and increasing the blast resistance. Notably, we found that key gene haplotypes controlling plant architecture, yield components, and pest and disease resistance, including IPA1, SMG1, DEP3, Pib, Pi-d2, and Bph3, were introduced from XI rice by introgression. By GWAS analysis, we detected a GN-related gene Gnd5, which had been consistently introgressed from XI into GJ cultivars since the 1980s. Gnd5 is a GRAS transcription factor gene, and Gnd5 knockout mutants showed a significant reduction in GN. The estimated genetic effects of genes varied among different breeding locations, which explained the distinct introgression levels of XI gene haplotypes, including Gnd5, DEP3, etc., to these GJ breeding pedigrees. These findings reveal the genomic contributions of introgressions from XI to the trait improvements of GJ rice cultivars and provide new insights for future rice genomic breeding.
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Oryza , Alelos , Resistencia a la Enfermedad/genética , Genómica , Oryza/genética , FitomejoramientoRESUMEN
Weedy rice (Oryza sativa f. spontanea) is a relative of cultivated rice that propagates in paddy fields and has strong drought resistance. In this study, we used 501 rice accessions to reveal the selection mechanism of drought resistance in weedy rice through a combination of selection analysis, genome-wide association studies, gene knockout and overexpression analysis, and Ca2+ and K+ ion flux assays. The results showed that the weedy rice species investigated have gene introgression with cultivated rice, which is consistent with the hypothesis that weedy rice originated from de-domestication of cultivated rice. Regions related to tolerance have particularly diversified during de-domestication and three drought-tolerance genes were identified. Of these, Os01g0800500 was also identified using an assay of the degree of leaf withering under drought, and it was named as PAPH1, encoding a PAP family protein. The drought-resistance capacity of PAPH1-knockout lines was much lower than that of the wild type, while that of overexpression lines was much higher. Concentrations of Ca2+ and K+ were lower in the knockout lines and higher in the overexpression lines compared with those of the wild type, suggesting that PAPH1 plays important roles in coping with drought stress. Our study therefore provides new insights into the genetic mechanisms underlying adaptive tolerance to drought in wild rice and highlights potential new resistance genes for future breeding programs in cultivated rice.
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Oryza , Sequías , Evolución Molecular , Estudio de Asociación del Genoma Completo , Oryza/genética , Fitomejoramiento , MalezasRESUMEN
Background: An increasing number of coronary heart disease (CHD) patients with an aging population are demanding available and effective out-of-hospital continuous healthcare services. However, great efforts still need to be made to promote out-of-hospital healthcare services for better CHD secondary prevention. This study aims to evaluate the effectiveness of a hospital-community-family (HCF)-based integrated healthcare model on treatment outcomes, treatment compliance, and quality of life (QoL) in CHD patients. Methods: A quasi-randomized controlled trial was conducted at the Department of Cardiology, a tertiary A-level hospital, Wuhan, China from January 2018 to January 2020 in accordance with the Consolidated Standards of Reporting Trials guidelines. CHD patients were enrolled from the hospital and quasi-randomly assigned to either HCF-based integrated healthcare model services or conventional healthcare services. The treatment outcomes and QoL were observed at the 12-month follow-up. Treatment compliance was observed at the 1-month and 12-month follow-ups. Results: A total of 364 CHD patients were quasi-randomly assigned to either integrated healthcare model services (n = 190) or conventional healthcare services (n = 174). Treatment outcomes including relapse and readmission rate (22.6% vs 41.9%; relative risk [RR] = 0.54; 95% confidence interval [CI], 0.40-0.74; p = 0.0031), the occurrence of major cardiovascular events (19.5% vs 45.4%; RR = 0.43; 95% CI, 0.30-0.59; p = 0.0023), complication rate (19.5% vs 35.0%; RR = 0.56; 95% CI, 0.39-0.79; p = 0.0042), and the control rate of CHD risk factors (p < 0.05, average p = 0.009) at the 12-month follow-up in the intervention group were better than those of the control group. There was no significant difference in treatment compliance at the 1-month follow-up between groups (p > 0.05, average p = 0.872). Treatment compliance at the 12-month follow-up in the intervention group, including correct medication, reasonable diet, adherence to exercise, emotional control, self-monitoring, and regular re-examination, was higher than that of the control group (p < 0.05, average p = 0.007). No difference was found in the compliance with smoking cessation and alcohol restriction at the 12-month follow-up between groups (p = 0.043). QoL at the 12-month follow-up in the intervention group was better than that of the control group (86.31 ± 9.39 vs 73.02 ± 10.70, p = 0.0048). Conclusions: The integrated healthcare model effectively improves treatment outcomes, long-term treatment compliance, and QoL of patients, and could be implemented as a feasible strategy for CHD secondary prevention.
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BACKGROUND: Mitral regurgitation (MR) is a rather common valvular heart disease. The aim of this systematic review and meta-analysis was to compare the outcomes, and complications of mitral valve (MV) replacement with surgical MV repair of non-ischemic MR (NIMR) METHODS: MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were searched until October, 2020. Studies were eligible for inclusion if they included patients with MR and reported early (30-day or in-hospital) or late all-cause mortality. For each study, data on all-cause mortality and incidence of reoperation and operative complications in both groups were used to generate odds ratios (ORs) or hazard ratios (HRs). This study is registered with PROSPERO, CRD42018089608. RESULTS: The literature search yielded 4834 studies, of which 20 studies, including a total of 21,898 patients with NIMR, were included. The pooled analysis showed that lower age, less female inclusion and incident of hypertension, significantly higher rates of diabetes and atrial fibrillation in the MV replacement group than MV repair group. No significant differences in the rates of pre-operative left ventricle ejection fraction (LVEF) and heart failure were observed between groups. The number of patients in the MV repair group was lower than in the MV replacement group. We found that there were significantly increased risks of mortality associated with replacement of MR. Moreover, the rate of re-operation and post-operative MR in the MV repair group was lower than in the MV replacement group. CONCLUSIONS: In patients with NIMR, MV repair achieves higher survival and leads to fewer complications than surgical MV replacement. In light of these results, we suggest that MV repair surgery should be a priority for NIMR patients.
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Procedimientos Quirúrgicos Cardíacos/efectos adversos , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Insuficiencia de la Válvula Mitral/cirugía , Válvula Mitral/cirugía , Anciano , Procedimientos Quirúrgicos Cardíacos/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Insuficiencia de la Válvula Mitral/mortalidad , Oportunidad Relativa , Complicaciones Posoperatorias , Modelos de Riesgos Proporcionales , Sesgo de Publicación , Reoperación/estadística & datos numéricos , Volumen Sistólico , Resultado del TratamientoRESUMEN
Drought is a complicated abiotic stress factor with severe effects on rice growth and production. Weedy rice is a valuable genetic resource that possesses a strong capacity for drought tolerance, cold tolerance, and salt tolerance, and is an excellent material for studying rice tolerance. Here, according to comprehensive tolerance to drought index D, accession WR16 was selected based on strong drought tolerance among 133 studied weedy red rice germplasms. WR16 was compared with Oryza sativa ssp. Japonica. cv. IAPAR-9, a reference genotype originating from Brazil. In addition, accession WR24 was classified as moderately tolerant to drought accessions. Transcriptomic and proteomic analyses were combined to identify 38 co-upregulated proteins related to drought tolerance, and targeted parallel reaction monitoring (PRM) was used to precisely quantify and verify nine proteins in the complex backgrounds. Result showed that six proteins were significantly (Fisher's exact P value < 0.05) related to drought tolerance in accessions WR16 and WR24. Among them, OS09T0478300-01, OS09T0530300-01, and OS01T0800500-01 formed a combined defense system to respond to drought stress in weedy rice. Results of these studies provide comprehensive information for precisely identifying and verifying tolerance to drought proteins and lay a solid theoretical foundation for research on drought tolerance mechanisms.
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Resistencia a la Enfermedad , Regulación de la Expresión Génica de las Plantas , Genotipo , Oryza , Proteínas de Plantas , Estrés Fisiológico , Deshidratación/genética , Deshidratación/metabolismo , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/biosíntesis , Proteínas de Plantas/genéticaRESUMEN
Weedy rice (WR) (Oryza sativa f. spontanea) is considered to be a pest in modern rice production systems because it competes for resources, has poor yield characteristics, and subsequently has a negative effect on rice grain yield. The evolutionary relationships among WR, landrace rice (LR), improved rice (IR) cultivars, and wild rice are largely unknown. In this study, we conducted a population genetic analysis based on neutral markers and gene haplotypes in 524 rice accessions and a comparative transcriptomic analysis using 15 representative samples. The results showed that WR populations have the highest level of genetic diversity (H e = 0.8386) and can be divided into two groups (japonica-type and indica-type). The japonica-type WR accessions from Heilongjiang province (HLJ), Jilin province (JL), Liaoning province (LN), and NX provinces clustered with the landraces grown in these same provinces. The indica-types from Jiangsu province (JS) also clustered with the indica-type landraces from JS province. Comparative transcriptome analysis of WR' IR and LR from HLJ, JL, and LN provinces showed that the WR still clustered with the LR, and that the IR lines comprise a single population. Thirty-two differentially expressed genes were shared by the IR and LR groups as well as between the IR and WR groups. Using Gene ontology (GO) analysis, we identified 19 shared GO terms in the IR and LR groups as well as between the IR and WR groups. Our results suggest that WR populations in China have diverse origins, and comparative transcriptome analysis of different types of rice from HLJ, JL, and LN provinces suggests that IR populations have become a end point in the evolution of WR, which provides a new perspective for the study of WR origins and lays a solid foundation for rice breeding.
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In this study, the cold-tolerance capacity of 133 varieties of weedy rice was evaluated based on the comprehensive evaluation index D, with Kongyu 131 used as a cold-tolerant control. A total of 39.8% of the 133 varieties were considered 'strong', indicating that weedy rice populations indeed have relatively strong cold-tolerance capacity as a whole, and the robust cold-tolerant varieties WR29 and WR157 were identified. Regression analysis showed that the metrics including the nitrogen recovery index, superoxide dismutase (SOD) content and malondialdehyde (MDA) content correlated significantly (P < 0.05) with cold tolerance and could be used as indicators of cold tolerance. On the basis of a transcriptome analysis of WR157, a robust cold-tolerant variety identified in this study, a total of 4645 putative DEGs were identified in treated groups compared to the control groups, with 2123 upregulated DEGs and 2522 downregulated DEGs. All upregulated DEGs were enriched on 1388 terms, all downregulated DEGs were enriched on 1566 terms; 911 of the 2123 upregulated DEGs fell into 98 KEGG categories and 1103 of the 2522 downregulated DEGs were in 115 categories. Further analysis showed that GO:0019740 and GO:0006808 are involved in nitrogen utilization; GO:0009269 and GO:0009414 are related to the stress response; and GO:0016491 and GO:0016614 are related to oxidoreductase activity. BACKGROUND: Weedy rice (Oryza) is a related pest species of cultivated rice (Oryza sativa L.) that has strong abiotic stress resistance; however, the comprehensive mechanism governing its cold tolerance is poorly understood. CONCLUSION: Our comprehensive evaluation based on five morphological indices and nine physiological indicators revealed outstanding levels of cold-tolerance capacity among weedy rice varieties from different regions and revealed some terms related to cold tolerance via transcriptome analysis. Our results underscored the reliable evaluation methods for additional cold tolerance studies and revealed several genes related to cold tolerance, which will help researchers breed cultivated rice varieties to increase their cold-tolerance capacity. These traits have the ability to increase seedling survival rate and growth, as well as future yields.
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Traditional rice landraces grown under on-farm conservation conditions by indigenous farmers are extremely important for future crop improvement. However, little is known about how the natural selection and agriculture practices of indigenous farmers interact to shape and change the population genetics of rice landraces grown under on-farm conservation conditions during the domestication. In this study, we sequenced DNA from 108 core on-farm conserved rice landraces collected from the ethnic minority regions of Yunnan, China, including 56 accessions collected in 1980 and 52 accessions collected in 2007 and obtained 2,771,245 of credible SNPs. Our findings show that most genetic diversity was retained during the 27 years of domestication by on-farm conservation. However, SNPs with marked allele frequency differences were found in some genome regions, particularly enriched in genic regions, indicating changes in genic regions may have played a much more prominent role in the short-term domestication of 27 years. We identified 186 and 183 potential selective-sweep regions in the indica and japonica genomes, respectively. We propose that on-farm conserved rice landraces during the short-term domestication had a highly polygenic basis with many loci responding to selection rather than a few loci with critical changes in response to selection. Moreover, loci affecting important agronomic traits and biotic or abiotic stress responses have been particularly targeted in selection. A genome-wide association study identified 90 significant signals for six traits, 13 of which were in regions of selective sweeps. Moreover, we observed a number of significant and interesting associations between loci and environmental factors, which implies adaptation to local environment. Our results provide insights into short-term evolutionary processes and shed light on the underlying mechanisms of on-farm conservation.
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OBJECTIVE: This study aimed to determine the association between hearing loss and cognitive function by gender in a nationally representative sample of older adults. METHODS: We used data from the National Health and Nutrition Examination Survey (2010-2011) for 655 participants aged 60 to 69 years. The cognitive functioning component consisted of the Consortium to Establish a Registry for Alzheimer's disease, the Animal Fluency Test, and the Digit Symbol Substitution Test. We created a composite z score to represent global cognitive function. Regression models were used to examine the association between hearing loss and cognitive function. RESULTS: Moderate/severe hearing loss was significantly associated with lower composite z score in males (ß = -28.67, 95% confidence interval [95% CI] = -57.13 to -0.20) but not in females (ß = -8.82, 95% CI = -36.61 to 18.96). CONCLUSION: There were gender differences in the association between hearing loss and cognitive function. Future studies need to investigate these gender-specific associations.
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Cognición/fisiología , Pérdida Auditiva/epidemiología , Pruebas Neuropsicológicas/estadística & datos numéricos , Audiometría de Tonos Puros , Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas Nutricionales , Factores Sexuales , Estados Unidos/epidemiologíaRESUMEN
Rice landraces, a genetic reservoir for varietal improvement, are developed by farmers through artificial selection during the long-term domestication process. To efficiently conserve, manage, and use such germplasm resources, an understanding of the genetic structure and differentiation of local rice landraces is required. In this study, we analyzed 188 accessions of rice landraces collected from localities across an altitudinal gradient from 425 to 2, 274 m above sea level in Yunnan Province, China using ten target genes and 48 SSR markers. We detected clear differentiation of the rice landraces into indica and japonica groups and further separation of the accessions in each group into two subgroups according to altitude, including a lower altitude subgroup and higher altitude subgroup. The AMOVA results showed significant genetic differentiation among altitude zones at SSRs and most genes, except Os1977 and STS22. We further determined that differentiation among landrace populations followed a model of isolation by altitude, in which gene flow was higher among populations at similar altitude levels than across different altitude levels. Our findings demonstrated that both adaptation to altitude and altitude-dependent gene flow played key roles in the genetic differentiation of rice landraces in Yunnan, China.
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Adaptación Fisiológica/genética , ADN de Plantas/genética , Oryza/genética , Filogenia , Altitud , China , Flujo Génico , Haplotipos , Repeticiones de Microsatélite , Oryza/clasificación , Polimorfismo Genético , Análisis de Componente PrincipalRESUMEN
BACKGROUND: Crop genetic resources are important components of biodiversity. However, with the large-scale promotion of mono-cropping, genetic diversity has largely been lost. Ex-situ conservation approaches were widely used to protect traditional crop varieties worldwide. However, this method fails to maintain the dynamic evolutionary processes of crop genetic resources in their original habitats, leading to genetic diversity reduction and even loss of the capacity of resistance to new diseases and pests. Therefore, on-farm conservation has been considered a crucial complement to ex-situ conservation. This study aimed at clarifying the genetic diversity differences between ex-situ conservation and on-farm conservation and to exploring the influence of traditional cultures on genetic diversity of rice landraces under on-farm conservation. METHODS: The conservation status of rice landrace varieties, including Indica and Japonica, non-glutinous rice (Oryza sativa) and glutinous rice (Oryza sativa var. glutinosa Matsum), was obtained through ethno-biology investigation method in 12 villages of ethnic groups from Guizhou, Yunnan and Guangxi provinces of China. The genetic diversity between 24 pairs of the same rice landraces from different times were compared using simple sequence repeat (SSR) molecular markers technology. The landrace paris studied were collected in 1980 and maintained ex-situ, while 2014 samples were collected on-farm in southwest of China. RESULTS: The results showed that many varieties of rice landraces have been preserved on-farm by local farmers for hundreds or thousands of years. The number of alleles (Na), effective number of alleles (Ne), Nei genetic diversity index (He) and Shannon information index (I) of rice landraces were significantly higher by 12.3-30.4 % under on-farm conservation than under ex-situ conservation. Compared with the ex-situ conservation approach, rice landraces under on-farm conservation programs had more alleles and higher genetic diversity. In every site we investigated, ethnic traditional cultures play a positive influence on rice landrace variety diversity and genetic diversity. CONCLUSION: Most China's rice landraces were conserved in the ethnic areas of southwest China. On-farm conservation can effectively promote the allelic variation and increase the genetic diversity of rice landraces over the past 35 years. Moreover, ethnic traditional culture practices are a crucial foundation to increase genetic diversity of rice landraces and implement on-farm conservation.
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Oryza/genética , China , Conservación de los Recursos Naturales , Productos Agrícolas/genética , Cultura , Variación Genética , Repeticiones de MicrosatéliteRESUMEN
KEY MESSAGE: Diachronic analysis showed no significant changes in the level of genetic diversity occurred over the past 27 years' domestication, which indicated genetic diversity was successfully maintained under on-farm conservation. Rice (Oryza sativa L.) is one of the earliest domesticated crop species. Its genetic diversity has been declining as a result of natural and artificial selection. In this study, we performed the first analysis of the levels and patterns of nucleotide variation in rice genomes under on-farm conservation in Yunnan during a 27-year period of domestication. We performed large-scale sequencing of 600 rice accessions with high diversity, which were collected in 1980 and 2007, using ten unlinked nuclear loci. Diachronic analysis showed no significant changes in the level of genetic diversity occurring over the past 27 years' domestication, which indicated genetic diversity was successfully maintained under on-farm conservation. Population structure revealed that the rice landraces could be grouped into two subpopulations, namely the indica and japonica groups. Interestingly, the alternate distribution of indica and japonica rice landraces could be found in each ecological zone. The results of AMOVA showed that on-farm conservation provides opportunities for continued differentiation and variation of landraces. Therefore, dynamic conservation measures such as on-farm conservation (which is a backup, complementary strategy to ex situ conservation) should be encouraged and enhanced, especially in crop genetic diversity centers. The results of this study offered accurate insights into short-term evolutionary processes and provided a scientific basis for on-farm management practices.
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Conservación de los Recursos Naturales , Variación Genética , Genoma de Planta , Oryza/genética , China , Productos Agrícolas/genética , ADN de Plantas/genética , Genética de Población , Genotipo , Haplotipos , Repeticiones de Microsatélite , Modelos Genéticos , Filogenia , Análisis de Secuencia de ADNRESUMEN
Low temperature affects the rice plants at all stages of growth. It can cause severe seedling injury and male sterility resulting in severe yield losses. Using a mini core collection of 174 Chinese rice accessions and 273 SSR markers we investigated cold tolerance at the germination and booting stages, as well as the underlying genetic bases, by association mapping. Two distinct populations, corresponding to subspecies indica and japonica showed evident differences in cold tolerance and its genetic basis. Both subspecies were sensitive to cold stress at both growth stages. However, japonica was more tolerant than indica at all stages as measured by seedling survival and seed setting. There was a low correlation in cold tolerance between the germination and booting stages. Fifty one quantitative trait loci (QTLs) for cold tolerance were dispersed across all 12 chromosomes; 22 detected at the germination stage and 33 at the booting stage. Eight QTLs were identified by at least two of four measures. About 46% of the QTLs represented new loci. The only QTL shared between indica and japonica for the same measure was qLTSSvR6-2 for SSvR. This implied a complicated mechanism of old tolerance between the two subspecies. According to the relative genotypic effect (RGE) of each genotype for each QTL, we detected 18 positive genotypes and 21 negative genotypes in indica, and 19 positive genotypes and 24 negative genotypes in japonica. In general, the negative effects were much stronger than the positive effects in both subspecies. Markers for QTL with positive effects in one subspecies were shown to be effective for selection of cold tolerance in that subspecies, but not in the other subspecies. QTL with strong negative effects on cold tolerance should be avoided during MAS breeding so as to not cancel the effect of favorable QTL at other loci.
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Mapeo Cromosómico/métodos , Cromosomas de las Plantas/genética , ADN de Plantas/análisis , Variación Genética , Oryza/crecimiento & desarrollo , Frío , Estudios de Asociación Genética , Germinación , Repeticiones de Microsatélite , Oryza/genética , Sitios de Carácter Cuantitativo , Especificidad de la Especie , Estrés FisiológicoRESUMEN
The quantitative trait loci (QTLs) for the dead leaf rate (DLR) and the dead seedling rate (DSR) at the different rice growing periods after transplanting under alkaline stress were identified using an F(2:3) population, which included 200 individuals and lines derived from a cross between two japonica rice cultivars Gaochan 106 and Changbai 9 with microsatellite markers. The DLR detected at 20 days to 62 days after transplanting under alkaline stress showed continuous normal or near normal distributions in F(3) lines, which was the quantitative trait controlled by multiple genes. The DSR showed a continuous distribution with 3 or 4 peaks and was the quantitative trait controlled by main and multiple genes when rice was grown for 62 days after transplanting under alkaline stress. Thirteen QTLs associated with DLR were detected at 20 days to 62 days after transplanting under alkaline stress. Among these, qDLR9-2 located in RM5786-RM160 on chromosome 9 was detected at 34 days, 41 days, 48 days, 55 days, and 62 days, respectively; qDLR4 located in RM3524-RM3866 on chromosome 4 was detected at 34 days, 41 days, and 48 days, respectively; qDLR7-1 located in RM3859-RM320 on chromosome 7 was detected at 20 days and 27 days; and qDLR6-2 in RM1340-RM5957 on chromosome 6 was detected at 55 days and 62 days, respectively. The alleles of both qDLR9-2 and qDLR4 were derived from alkaline sensitive parent "Gaochan106". The alleles of both qDLR7-1 and qDLR6-2 were from alkaline tolerant parent Changbai 9. These gene actions showed dominance and over dominance primarily. Six QTLs associated with DSR were detected at 62 days after transplanting under alkaline stress. Among these, qDSR6-2 and qDSR8 were located in RM1340-RM5957 on chromosome 6 and in RM3752-RM404 on chromosome 8, respectively, which were associated with DSR and accounted for 20.32% and 18.86% of the observed phenotypic variation, respectively; qDSR11-2 and qDSR11-3 were located in RM536-RM479 and RM2596-RM286 on chromosome 11, respectively, which were associated with DSR explaining 25.85% and 15.41% of the observed phenotypic variation, respectively. The marker flanking distances of these QTLs were quite far except that of qDSR6-2, which should be researched further.
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Oryza/genética , Oryza/fisiología , Hojas de la Planta/genética , Sitios de Carácter Cuantitativo , Plantones/genética , Estrés Fisiológico , Cruzamiento , Genes de Plantas/genética , Variación Genética , Concentración de Iones de Hidrógeno , Repeticiones de Microsatélite/genética , Oryza/efectos de los fármacos , Oryza/crecimiento & desarrollo , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/fisiología , Tolerancia a la Sal/genética , Sales (Química)/farmacología , Plantones/efectos de los fármacos , Plantones/crecimiento & desarrollo , Plantones/fisiologíaRESUMEN
The quantitative trait loci (QTLs) for the seedling vigor traits under 12 degrees C cold water irrigation, such as the seedling height, the seedling fresh weight, the seedling dry weight, and their cold response index, were identified using an F(2/3) population including 200 individuals and lines derived from a cross of indica and japonica "Milyang 23/Jileng 1" with microsatellite markers. All seedling vigor traits exhibited a continuous distribution near normal in F3 lines; these traits were quantitative traits controlled by multiple genes. Twelve QTLs conferring the seedling vigor traits under cold water irrigation were detected on chromosomes 1, 2, 7, 8, and 12, which explained the observed phenotypic variance from 5.2% to 17.9%. Among them, qCSH2 and qCSH12 were located in RM262-RM263 on chromosome 2 and RM270-RM17 on chromosome 12, respectively, which were associated with the seedling height. qSDW12 and qCSDW1 were located in RM19-RM270 on chromosome 12 and RM129-RM9 on chromosome 1, respectively, which were correlated with the seedling dry weight and its cold response index, and the explained 16.6%, 17.9%, 15.9%, and 16.2% of the observed phenotypic variation, respectively. These QTLs alleles were derived from cold-tolerant parent Jileng 1; the gene actions of the two front genes showed their additive effect, and the two genes blind showed dominant and over dominant effects, respectively.
Asunto(s)
Genes de Plantas/fisiología , Oryza/genética , Sitios de Carácter Cuantitativo , Plantones/genética , Cromosomas de las Plantas , Frío , Oryza/fisiología , Plantones/fisiologíaRESUMEN
The quantitative trait loci (QTLs) for low-temperature vigor of germination (LVG) with a germination period of 7 d, 11 d, 14 d, and 17 d at 14 degrees C was identified using F(2:3) population, which included 200 individuals and lines derived from a cross of indica and japonica "Milyang 23/Jileng 1" with microsatellite markers. The correlation coefficient between LVG and other cold tolerance traits was analyzed. LVG and the cold response index for vigor of germination (CIVG) detected when the germination period was 7 d showed a continuous distribution, which was partial to lower LVG and lower CIVG in F(3) lines. LVG and CIVG detected when the germination periods were 11 d, 14 d, and 17 d showed a continuous distribution near normal, which were quantitative traits controlled by multiple genes. LVG detected when the germination period was 14 d was more correlated with other cold tolerance traits than LVG detected when the germination periods were 7 d, 11 d, and 17 d, which was significantly associated with cold tolerance during the bud bursting period, the seedling stage, the booting stage, and the growing ability under cold conditions. qLVG2 located in RM29-RM262 on chromosome 2, qLVG7-2 and qCIVG7-2 located in RM336-RM118 on chromosome 7 were detected when the germination periods were 11 d, 14 d, and 17 d. qCIVG2 located in RM29-RM262 on chromosome 2 was detected when the germination periods were 11 d and 14 d. The variation is due to the observed phenotypic variation by the above QTLs, which was increased following the germination. The variation of qLVG2 related to LVG was increased from 6.9% to 14.2%. The variation of qLVG7-2 associated with LVG was increased from 9.9% to 11.2%. The variation of qCIVG2 correlated with CIVG was increased from 6.3% to 9.0%. The variation of qCIVG7-2 associated with CIVG was increased from 8.3% to 12.9%. These QTL alleles were obtained from the tolerant parent Jileng 1, and the gene action was most likely to be partially dominant.