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1.
Salinity stress is a major limitation in barley production. Substantial genetic variation in tolerance occurs among genotypes of barley, so the development of salt-tolerant cultivars is a potentially effective approach for minimizing yield losses. The lack of economically viable methods for screening salinity tolerance in the field remains an obstacle to breeders, and molecular marker-assisted selection is a promising alternative. In this study, salinity tolerance of 172 doubled-haploid lines generated from YYXT (salinity-tolerant) and Franklin (salinity-sensitive) was assessed in glasshouse trials during the vegetative phase. A high-density genetic linkage map was constructed from 76 pairs of simple sequence repeats and 782 Diversity Arrays Technology markers which spanned a total of 1,147 cM. Five significant quantitative trait loci (QTL) for salinity tolerance were identified on chromosomes 1H, 2H, 5H, 6H and 7H, accounting for more than 50% of the phenotypic variation. The tolerant variety, YYXT, contributed the tolerance to four of these QTL and Franklin contributed the tolerance to one QTL on chromosome 1H. Some of these QTL mapped to genomic regions previously associated with salt tolerance in barley and other cereals. Markers associated with the major QTL identified in this study have potential application for marker-assisted selection in breeding for enhanced salt tolerance in barley.  相似文献   

2.
Alkaline soil restricts soybean plant growth and yield. In our previous study, a major alkaline salt tolerance quantitative trait locus (QTL) was identified in soybean on chromosome 17. In this study, the residual heterozygous line (RHL46), which was selected from a population of F6 recombinant inbred lines (RILs) derived from a cross between an alkaline salt-sensitive soybean cultivar Jackson and a tolerant wild soybean accession JWS156-1, was used for validation and high-resolution mapping of the QTL. In a large segregating population (n = 1,109), which was produced by self-pollinating heterozygotes of RHL46, segregation of alkaline salt tolerance showed a continuous distribution, and the tolerant plants were predominant. Linkage mapping analysis revealed a major QTL with a large dominant effect for alkaline salt tolerance, and the highest LOD score was detected between the single sequence repeat (SSR) markers GM17-12.2 and Satt447. Furthermore, 10 fixed recombinant lines carrying chromosome fragments of different lengths in the QTL region were selected from the RHL46 progeny. Phenotype evaluation and SSR marker analysis of the recombinant lines narrowed down the QTL to a 3.33-cM interval region between the markers GM17-11.6 and Satt447 with a physical map length of approximately 771 kb. High-resolution mapping of the alkaline salt tolerance QTL will be useful not only for marker-assisted selection in soybean breeding programs but also for map-based cloning of the alkaline salt tolerance gene in order to understand alkaline salt tolerance in soybean and other plant species.  相似文献   

3.

Background

Drought and salinity are two major abiotic stresses that severely limit barley production worldwide. Physiological and genetic complexity of these tolerance traits has significantly slowed the progress of developing stress-tolerant cultivars. Marker-assisted selection (MAS) may potentially overcome this problem. In the current research, seventy two double haploid (DH) lines from a cross between TX9425 (a Chinese landrace variety with superior drought and salinity tolerance) and a sensitive variety, Franklin were used to identify quantitative trait loci (QTL) for drought and salinity tolerance, based on a range of developmental and physiological traits.

Results

Two QTL for drought tolerance (leaf wilting under drought stress) and one QTL for salinity tolerance (plant survival under salt stress) were identified from this population. The QTL on 2H for drought tolerance determined 42% of phenotypic variation, based on three independent experiments. This QTL was closely linked with a gene controlling ear emergency. The QTL on 5H for drought tolerance was less affected by agronomic traits and can be effectively used in breeding programs. A candidate gene for this QTL on 5H was identified based on the draft barley genome sequence. The QTL for proline accumulation, under both drought and salinity stresses, were located on different positions to those for drought and salinity tolerance, indicating no relationship with plant tolerance to either of these stresses.

Conclusions

Using QTL mapping, the relationships between QTL for agronomic and physiological traits and plant drought and salinity tolerance were studied. A new QTL for drought tolerance which was not linked to any of the studied traits was identified. This QTL can be effectively used in breeding programs. It was also shown that proline accumulation under stresses was not necessarily linked with drought or salinity tolerance based on methods of phenotyping used in this experiment. The use of proline content in breeding programs can also be limited by the accuracy of phenotyping.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-015-1243-8) contains supplementary material, which is available to authorized users.  相似文献   

4.
Micro satellite markers located in the Saltol QTL of 5 Mb region (10.4–15.6 Mb) in chromosome 1 confering seedling stage salt tolerance were used to evaluate 94 rice genotypes. Out of 21, eight SSR markers at Saltol region of Chromosome were found polymorphic. Based on the phenotypic screening, 94 genotypes were grouped as highly tolerant (20), tolerant (18) moderately tolerant (32), sensitive (19) and highly sensitive (5). The marker RM3412 appears to be diagnostic of salinity tolerance and associate to salinity tolerance at seedling stage as it is closely linked to SKC gene. Based on Saltol markers study, CSR 31, CSR 38, CSR 41, CSR 32, Wild 11, CSR 18, Azgo, Pant Dhan 4, Trichi 1, CSR 10 and IR64426-4B-11-1 could not be identified as tolerant genotypes though had expressed tolerant to highly tolerant phenotype to salinity stress at seedling stage, suggesting that QTLs other than Saltol might be controlling their salinity tolerance. It is suggested that these genotypes could serve as potentially novel germplasm and could be exploited for the development of new breeding lines with high level of salinity tolerance by pyramiding of the Saltol and other QTLs.  相似文献   

5.
The rootstock effect on the fruit yield of a grafted tomato variety was genetically analyzed under salinity using as rootstock two populations of F(9) lines developed from a salt sensitive genotype of Solanum lycopersicum var. cerasiforme, as female parent, and two salt tolerant lines, as male parents, from S. pimpinellifolium, the P population (123 lines), and S. cheesmaniae, the C population (100 lines). There were rootstock lines from the two populations (up to 65% in the P population) that raised the fruit yield of the commercial hybrid under saline conditions. It is shown that this salt tolerance rootstock effect is a heritable trait (h (2) near 0.3), governed by at least eight QTLs. The most relevant component was the number of fruits. Thus most detected QTLs correspond to this component. In general, QTL gene effects are medium-sized, with contributions from 8.5 up to 15.9% at most, and the advantageous allele comes from the wild, salt tolerant species. Only two fruit yield QTLs on chromosomes P9 and C11 might correspond to fruit yield QTLs of the non-grafted lines indicating their root system dependence. A fruit yield QTL on chromosome 3 is acting epistatically in both populations. The epistatic interactions found were dominant and they were unveiled using the associated marker as cofactor in the composite interval mapping methodology. Therefore, an efficient and profitable utilization of wild germplasm can be carried out through the improvement of rootstocks that confer salt tolerance in terms of fruit yield to the grafted variety.  相似文献   

6.

Introduction

Salinity is one of the major abiotic stresses affecting crop production via adverse effects of osmotic stress, specific ion toxicity, and stress-related nutritional disorders. Detrimental effects of salinity are also often exacerbated by low oxygen availability when plants are grown under waterlogged conditions. Developing salinity-tolerant varieties is critical to overcome these problems, and molecular marker assisted selection can make breeding programs more effective.

Methods

In this study, a double haploid (DH) population consisting of 175 lines, derived from a cross between a Chinese barley variety Yangsimai 1 (YSM1) and an Australian malting barley variety Gairdner, was used to construct a high density molecular map which contained more than 8,000 Diversity Arrays Technology (DArT) markers and single nucleotide polymorphism (SNP) markers. Salinity tolerance of parental and DH lines was evaluated under drained (SalinityD) and waterlogged (SalinityW) conditions at two different sowing times.

Results

Three quantitative trait loci (QTL) located on chromosome 1H, single QTL located on chromosomes 1H, 2H, 4H, 5H and 7H, were identified to be responsible for salinity tolerance under different environments. Waterlogging stress, daylight length and temperature showed significant effects on barley salinity tolerance. The QTL for salinity tolerance mapped on chromosomes 4H and 7H, QSlwd.YG.4H, QSlwd.YG.7H and QSlww.YG.7H were only identified in winter trials, while the QTL on chromosome 2H QSlsd.YG.2H and QSlsw.YG.2H were only detected in summer trials. Genes associated with flowering time were found to pose significant effects on the salinity QTL mapped on chromosomes 2H and 5H in summer trials. Given the fact that the QTL for salinity tolerance QSlsd.YG.1H and QSlww.YG.1H-1 reported here have never been considered in the literature, this warrants further investigation and evaluation for suitability to be used in breeding programs.  相似文献   

7.
花生苗期耐盐性评价及耐盐指标筛选   总被引:4,自引:0,他引:4  
评价鉴选耐盐品种对于盐碱地花生生产具有重要意义。采用盆栽试验,设置不同盐胁迫浓度,对200个花生品种(系)萌发至幼苗期通过出苗速度、植株形态和生物量等指标进行耐盐性系统评价。结果表明,随盐胁迫浓度的增加,出苗时间延长,植株形态建成抑制加重,物质积累减少。鉴选花生品种耐盐性强弱的适宜盐胁迫浓度为0.30%—0.45%,超过此浓度不能出苗。地上部形态和生物量可作为耐盐评价的首选指标,主根长和出苗速度可作为辅助指标用以判断花生品种的综合耐盐能力。200个品种(系)在不同盐胁迫浓度下均可分成高度耐盐型、耐盐型、盐敏感型和高度盐敏感型4组。耐盐品种数量随盐胁迫强度加大而下降,盐敏感品种数量则上升。0.15%浓度下200个品种全部出苗,4个类型品种数分别占供试材料的29.0%、39.0%、27.5%和4.5%;0.30%浓度下185个品种出苗,4个类型品种数分别占供试材料的5.5%、34.5%、23.5%和29.0%;0.45%浓度下107个品种出苗,4个类型品种数分别占供试材料的5.5%、5.5%、20.0%和22.5%。14个品种在各盐浓度胁迫下均表现耐性,10个品种在各盐浓度胁迫下均表现敏感,为花生耐盐机理研究及生产应用提供了不同类型材料。  相似文献   

8.
The sodium and potassium concentrations in leaf and stem have been genetically studied as physiological components of the vegetative and reproductive development in two populations of F8 lines, derived from a salt sensitive genotype of Solanum lycopersicum cv. Cerasiforme, as female parent, and two salt tolerant lines, as male parents, from S. pimpinellifolium, the P population (142 lines), and S. cheesmaniae, the C population (116 lines). Genetic parameters of ten traits under salinity and five of them under control conditions were studied by ANOVA, correlation, principal component and QTL analysis to understand the global response of the plant. Two linkage maps including some tomato flowering time and salt tolerance candidate genes encoding for SlSOS1, SlSOS2, SlSOS3, LeNHX1, LeNHX3, were used for the QTL detection. Thirteen and 20 QTLs were detected under salinity in the P and C populations, respectively, and four under control conditions. Highly significant and contributing QTLs (over 40%) for the concentrations of Na+ and K+ in stems and leaves have been detected on chromosome 7 in both the populations. This is the only genomic position where the concentration QTLs for both the cations locate together. The proportion of QTLs significantly affected by salinity was larger in the P population (64.3%, including all QTLs detected under control) than in the C population (21.4%), where the estimated genetic component of variance was larger for most traits. A highly significant association between the leaf area and fruit yield under salinity was found only in the C population, which is supported by the location of QTLs for these traits in a common region of chromososome C1. As far as breeding for salt tolerance is concerned, only two sodium QTLs (lnc1.1 and lnc8.1) map in genomic regions of C1 and C8 where fruit yield QTLs are also located but in both the cases the profitable allele corresponds to the salt sensitive, cultivated species. One of those QTLs, lnc1.1 might involve LeNHX3.  相似文献   

9.
10.
11.
Acid soil/aluminium toxicity is one of the major constraints on barley production around the world. Genetic improvement is the best solution and molecular-marker-assisted selection has proved to be an efficient tool for developing barley cultivars with acid soil/aluminium tolerance. In this study, barley variety Svanhals—introduced from CYMMIT (International Maize and Wheat Improvement Center)—was identified as acid soil/aluminium tolerant and the tolerance was mapped to chromosome 4H in 119 doubled haploid (DH) lines from a cross of Hamelin/Svanhals. The HvMATE gene, encoding an aluminium-activated citrate transporter, was selected as a candidate gene and gene-specific molecular markers were developed to detect acid soil/aluminium tolerance based on the polymerase chain reaction. Sequence analysis of the HvMATE gene identified a 21-bp indel (insertion–deletion) between the tolerant and sensitive cultivars. The new marker was further mapped to the QTL (quantitative trait loci) region on chromosome 4H for acid soil tolerance and accounted for 66.9 % of phenotypic variation in the DH population. Furthermore, the polymorphism was confirmed in other tolerant varieties which have been widely used as a source of acid soil tolerance in Australian barley breeding programs. The new gene-specific molecular marker provides an effective and simple molecular tool for selecting the acid soil tolerance gene from multiple tolerance sources.  相似文献   

12.
R Xu  J Wang  C Li  P Johnson  C Lu  M Zhou 《PloS one》2012,7(8):e43079

Introduction

Salinity and waterlogging are two major abiotic stresses severely limiting barley production. The lack of a reliable screening method makes it very hard to improve the tolerance through breeding programs.

Methods

This work used 188 DH lines from a cross between a Chinese landrace variety, TX9425 (waterlogging and salinity tolerant), and a Japanese malting barley, Naso Nijo (waterlogging and salinity sensitive), to identify QTLs associated with the tolerance.

Results

Four QTLs were found for waterlogging tolerance. The salinity tolerance was evaluated with both a hydroponic system and in potting mixture. In the trial with potting mixture, only one major QTL was identified to associate with salinity tolerance. This QTL explained nearly 50% of the phenotypic variation, which makes it possible for further fine mapping and cloning of the gene. This QTL was also identified in the hydroponic experiment for different salt-related traits. The position of this QTL was located at a similar position to one of the major QTLs for waterlogging tolerance, indicating the possibility of similar mechanisms controlling both waterlogging and salinity tolerance.

Conclusion

The markers associated with the QTL provided a unique opportunity in breeding programs for selection of salinity and waterlogging tolerance.  相似文献   

13.
Salt tolerance has been analysed in two populations of F7 lines developed from a salt sensitive genotype of Solanum lycopersicum var. cerasiforme, as female parent, and two salt tolerant lines, as male parents, from S. pimpinellifolium, the P population (142 lines), and S. cheesmaniae, the C population (116 lines). Salinity effects on 19 quantitative traits including fruit yield were investigated by correlation, principal component analysis, ANOVA and QTL analysis. A total of 153 and 124 markers were genotyped in the P and C populations, respectively. Some flowering time and salt tolerance candidate genes were included. Since most traits deviated from a normal distribution, results based on the Kruskal–Wallis non-parametric test were preferred. Interval mapping methodology and ANOVA were also used for QTL detection. Eight out of 15 QTLs at each population were detected for the target traits under both control and high salinity conditions, and among them, only average fruit weight (FW) and fruit number (FN) QTLs (fw1.1, fw2.1 and fn1.2) were detected in both populations. The individual contribution of QTLs were, in general, low. After leaf chloride concentration, flowering time is the trait most affected by salinity because different QTLs are detected and some of their QTL×E interactions have been found significant. Also reinforcing the interest on information provided by QTL analysis, it has been found that non-correlated traits may present QTL(s) that are associated with the same marker. A few salinity specific QTLs for fruit yield, not associated with detrimental effects, might be used to increase tomato salt tolerance. The beneficial allele at two of them, fw8.1 (in C) and tw8.1 (for total fruit weight in P) corresponds to the salt sensitive parent, suggesting that the effect of the genetic background is crucial to breed for wide adaptation using wild germplasm.  相似文献   

14.
Although the physiological consequences of plant growth under saline conditions have been well described, understanding the core mechanisms conferring plant salt adaptation has only started. We target the root plasma membrane proteomes of two barley varieties, cvs. Steptoe and Morex, with contrasting salinity tolerance. In total, 588 plasma membrane proteins were identified by mass spectrometry, of which 182 were either cultivar or salinity stress responsive. Three candidate proteins with increased abundance in the tolerant cv. Morex were involved either in sterol binding (a GTPase‐activating protein for the adenosine diphosphate ribosylation factor [ZIGA2], and a membrane steroid binding protein [MSBP]) or in phospholipid synthesis (phosphoethanolamine methyltransferase [PEAMT]). Overexpression of barley MSBP conferred salinity tolerance to yeast cells, whereas the knock‐out of the heterologous AtMSBP1 increased salt sensitivity in Arabidopsis. Atmsbp1 plants showed a reduced number of lateral roots under salinity, and root‐tip‐specific expression of barley MSBP in Atmsbp1 complemented this phenotype. In barley, an increased abundance of MSBP correlates with reduced root length and lateral root formation as well as increased levels of auxin under salinity being stronger in the tolerant cv. Morex. Hence, we concluded the involvement of MSBP in phytohormone‐directed adaptation of root architecture in response to salinity.  相似文献   

15.
Mapping QTLs for phosphorus deficiency tolerance in rice (Oryza sativa L.)   总被引:23,自引:0,他引:23  
 The amplified fragment length polymorphism (AFLP) technique combined with selective genotyping was used to map quantitative trait loci (QTLs) associated with tolerance for phosphorus (P) deficiency in rice. P deficiency tolerant cultivar IR20 was crossed to IR55178-3B-9-3 (sensitive to P-deficiency) and 285 recombinant inbred lines (RILs) were produced by single-seed descent. The RILs were phenotyped for the trait by growing them in P-sufficient (10.0 mg/l) and P-deficient (0.5 mg/l) nutrient solution and determining their relative tillering ability at 28 days after seeding, and relative shoot dry weight and relative root dry weight at 42 days after seeding. Forty two of each of the extreme RILs (sensitive and tolerant) and the parents were subjected to AFLP analysis. A map consisting of 217 AFLP markers was constructed. Its length was 1371.8 cM with an average interval size of 7.62 cM. To assign linkage groups to chromosomes, 30 AFLP and 26 RFLP markers distributed over the 12 chromosomes were employed as anchor markers. Based on the constructed map, a major QTL for P-deficiency tolerance, designated PHO, was located on chromosome 12 and confirmed by RFLP markers RG9 and RG241 on the same chromosome. Several minor QTLs were mapped on chromosomes 1, 6, and 9. Received: 21 April 1998 / Accepted: 9 June 1998  相似文献   

16.
The performance of a major quantitative trait locus (QTL) of terminal drought tolerance (DT) of pearl millet was assessed under salt stress. The test-cross hybrids of the QTL donor parent (drought tolerant, PRLT 2/89-33), QTL recipient parent (drought sensitive, H 77/833-2), and a set of six near isogenic lines introgressed with a terminal DT-QTL (QTL-NILs) were evaluated for germination and seedling emergence at 7 days after sowing (DAS) in Petri plates at four salinity levels, and at vegetative (24 DAS) and maturity stages at three salinity and alkalinity levels. Na+ and K+ accumulation, their compartmentation in different plant parts, and their effects on growth and yield parameters were evaluated. The DT-QTL donor parent and QTL-NILs accumulated less Na+ in shoot parts at seedling, vegetative and maturity stages, and also partitioned the accumulated Na+ more into nodes and internodes and less into leaves than the drought-sensitive recurrent parent. The pattern of reduced salt accumulation in the drought-tolerant parent and QTL-NILs was consistently associated with better growth and productivity in saline and alkaline treatments. It is concluded that the DT-QTL contributed by PRLT 2/89-33 exerted favourable effects on growth and productivity traits under salt stress by limiting Na+ accumulation in leaves.  相似文献   

17.
采用盆栽试验,设置不同盐胁迫浓度,通过萌发至幼苗期的出苗速度、植株形态和生物量等指标对200个花生品种(系)进行耐盐性评价.结果表明: 随盐胁迫浓度的增加,花生出苗时间延长,对植株形态建成抑制加重,物质积累减少.鉴定花生品种耐盐性强弱的适宜盐胁迫浓度为0.30%~0.45%.采用隶属函数值法将10个指标归结为平均隶属函数值,根据不同胁迫浓度下各指标与平均隶属函数值之间的相关性大小,植株鲜质量、地上部鲜质量、地下部鲜质量、地下部干质量、株高和主茎高均较大,可作为首选指标,植株干质量、地上部干质量、主根长和出苗速率均较小,可作为辅助指标综合判断品种的耐盐能力.200个品种(系)在不同盐胁迫浓度下均可分成高度耐盐型、耐盐型、盐敏感型和高度盐敏感型4组.随盐胁迫强度加大,耐盐品种数量下降,而盐敏感品种数量上升.部分品种在低、中、高盐胁迫强度下表现出统一性(均耐盐或均敏感);部分品种存在差异性,即低胁迫强度下表现耐盐性而在高胁迫强度下表现盐敏感性.  相似文献   

18.
19.

Key message

Differentially expressed antioxidant enzymes, amino acids and proteins in contrasting rice genotypes, and co-location of their genes in the QTLs mapped using bi-parental population, indicated their role in salt tolerance.

Abstract

Soil salinity is a major environmental constraint limiting rice productivity. Salt-tolerant ‘CSR27’, salt-sensitive ‘MI48’and their extreme tolerant and sensitive recombinant inbred line (RIL) progenies were used for the elucidation of salt stress tolerance metabolic pathways. Salt stress-mediated biochemical and molecular changes were analyzed in the two parents along with bulked-tolerant (BT) and bulked-sensitive (BS) extreme RILs. The tolerant parent and BT RILs suffered much lower reduction in the chlorophyll as compared to their sensitive counterparts. Activities of antioxidant enzymes superoxide dismutase (SOD) and peroxidase (POD) and non-enzymatic antioxidant ascorbic acid were much higher in salt-stressed CSR27 and BT RILs than MI48 and BS RILs. Further, the tolerant lines showed significant enhancement in the levels of amino acids methionine and proline in response to salt stress in comparison to the sensitive lines. Similarly, the tolerant genotypes showed minimal reduction in cysteine content whereas sensitive genotypes showed a sharp reduction. Real time PCR analysis confirmed the induction of methionine biosynthetic pathway (MBP) enzymes cystathionine-β synthase (CbS), S-adenosyl methionine synthase (SAMS), S-adenosyl methionine decarboxylase (SAMDC) and serine hydroxymethyl transferase (SHMT) genes in tolerant lines, suggesting potential role of the MBP in conferring salt tolerance in rice variety CSR27. Proteome profiling also confirmed higher expression of SOD, POD and plastidic CbS and other proteins in the tolerant lines, whose genes were co-located in the QTL intervals for salt tolerance mapped in the RIL population. The study signifies integrated biochemical-molecular approach for identifying salt tolerance genes for genetic improvement for stress tolerant rice varieties.
  相似文献   

20.
Study of genetic diversity in crop plants is essential for the selection of appropriate germplasm for crop improvement. As salinity posses a serious environmental challenge to rice production globally and especially in India, it is imperative that the study of large collections of germplasms be undertaken to search for salt tolerant stocks. In the present study, 64 indica germplasms were collected from different agro-climatic zones of West Bengal, India, from the Himalayan foothills in the northern part down to the southern saline belt of the state keeping in view the soil characteristics and other edaphic factors prevailing in the region. Salt tolerance parameters were used to screen the large set of germplasms in terms of root-shoot length, fresh-dry weight, chlorophyll content, Na+/K+ ratio and germination potential in presence of salt. Standard evaluation score or SES was calculated to find out tolerant to sensitive cultivar. Twenty-one SSR markers, some associated with the Saltol QTL and others being candidate gene based SSR (cgSSR) were used to study the polymorphism of collected germplasm. A wide diversity was detected among the collected germplasms at the phenotypic as well as molecular level. Of the 21 SSR markers, 15 markers were found to be polymorphic with 88 alleles. Based on phenotypic and biochemical results, 21 genotypes were identified as salinity tolerant, whereas 40 genotypes turned out to be salt susceptible. The present study shows that apart from the established salt tolerant lines, several other landraces like Bonkanta, Morisal, Ghiosh, Patni may be the source of salt tolerant donor in future breeding programs.  相似文献   

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