The wheat_ Thinopyrum intermedium addition lines Z1,Z2 contain a pair of Th. intermedium chromosomes 2Ai_2 carrying the gene with resistance to barley yellow dwarf virus (BYDV). Genomic in situ hybridizat...The wheat_ Thinopyrum intermedium addition lines Z1,Z2 contain a pair of Th. intermedium chromosomes 2Ai_2 carrying the gene with resistance to barley yellow dwarf virus (BYDV). Genomic in situ hybridization (GISH) was used to analyze the chromosome constitution of Z1,Z2 by using genomic DNA probes from Th. intermedium and Pseudoroegneria strigosa . The results showed that the chromosome constitution of either Z1 or Z2 composes of 42 wheat chromosomes and two Th. intermedium chromosomes (2Ai_2). The 2Ai_2 chromosome is St_E intercalary translocation, in which the E genomic chromosome segment translocated into the middle region of the long arm of chromosome belonging to St genome. With the genomic DNA probe of Ps. strigosa , the GISH pattern specific to the 2Ai_2 chromosome may be used as a molecular cytogenetic marker. A detailed RFLP analysis on Z1, Z2 and their parents was carried out by using 12 probes on the wheat group 2 chromosomes. Twenty RFLP markers specific to the 2Ai_2 chromosome were identified. Two RAPD markers of OPR16 -350 and OPH09 -1580 , specific to the 2Ai_2 chromosome, were identified from 280 RAPD primers. These molecular markers could be used to assisted_select translocation lines with small segment of the 2Ai_2 chromosome and provide tools to localize the BYDV resistance.展开更多
The wheatgrass, Thinopyrum intermedium (Host) Barkworth & DR Dewey, shows many beneficial characteristics, such as big spikes and high resistance to many diseases. To transfer the beneficial genes of this species, ...The wheatgrass, Thinopyrum intermedium (Host) Barkworth & DR Dewey, shows many beneficial characteristics, such as big spikes and high resistance to many diseases. To transfer the beneficial genes of this species, many wheat- Thinopyrum intermedium alien chromosome lines were developed. Of them, Shannong 0095 (SN0095), a disomic substitution, has long spikes and flag-leaves, and thus may be an important genetic resource for wheat yield improvement. In order to realize its heterosis and combining ability on major yield traits, a 7 ×7 complete diallel design was made according to Griffing's Method-1. The results showed that heterosis for spike length (SPL), flag-leaf area (FLA), number of spikes per plant (NSP), number of spikelets per spike (NSL), kernels per spike (KPS), 1 000-kernel weight (TKW) and grain yield per plant (GYP) existed in all the crosses by SN0095, but heterobeltiosis occurred only for KPS, TKW, and GYP. The relative mid-parent heterosis (RMH) and relative high-parent heterosis (RHH) for GYP, which valued as high as 35.32 and 29.92% respectively, were the highest among all the traits mearsured. Though additive and non-additive gene effects and cytoplasmic effects (or cytoplasmic-nuclear interaction effects) were found in governing all the traits measured above, additive gene action played a predominant role. The results also showed that SN0095 was the best-general combiner for SPL and FLA, and high-general combiner for NSP amongst all the parents. Estimates of specific combining ability (SCA) showed that SN0095 could also make high-SCA combinations for GYP, such as SN0095 × Jimai 19 (JMI9). SN0095 could be a unique and important parent in hybrid wheat breeding programs.展开更多
Thinopyrum intermedium has been used as a resource for improving resistance to biotic and abiotic stresses and yield potential in common wheat. Wheat line SN304 was derived from a cross between common wheat cultivar Y...Thinopyrum intermedium has been used as a resource for improving resistance to biotic and abiotic stresses and yield potential in common wheat. Wheat line SN304 was derived from a cross between common wheat cultivar Yannong 15 and Th. intermedium. Genomic in situ hybridization(GISH) produced no hybridization signal in SN304 using Th. intermedium genomic DNA as a probe, but fluorescence in situ hybridization(FISH) using oligonucleotides AFA-3, AFA-4, pAs1-1, pAs1-3, pAs1-4, pAs1-6, pSc119.2-1,and(GAA)10 as probes detected hybridization signals on chromosomes 2 A, 7 A, 2 B, 3 B, 6 B, and 7 B in SN304 that differed from Yannong 15. Results of specific markers also indicated that there were Th. intermedium chromatin introgressions on different chromosomes in SN304. In a hydroponic culture experiment, SN304 not only produced more biomass and higher stem and leaf dry weight but also accumulated more phosphorus than Yannong 15 under phosphorus-deficiency stress. Moreover, SN304 produced a lower pH and released more organic acids, especially oxalic acid, than Yannong 15, which suggests that SN304 exudates enabled more absorbance of P than Yannong 15 under comparable conditions.The results indicate that SN304 is a wheat-Th. intermedium introgression line with tolerance to phosphorus-deficiency stress.展开更多
The univalent from the meiosis-metaphase spreads of F1 (Z2× wheat variety Wan7107) wasidentified to be Agropyrum intermedium 2Ai-2 chromosome by GISH. The 2Ai-2 chromosomes weremicroisolated and collected. After ...The univalent from the meiosis-metaphase spreads of F1 (Z2× wheat variety Wan7107) wasidentified to be Agropyrum intermedium 2Ai-2 chromosome by GISH. The 2Ai-2 chromosomes weremicroisolated and collected. After two rounds of PCR amplification, the PCR products wereranged from 150-3 000 bp,with predominant fragments at about 200-2 000 bp. Using Ag.intermedium genomic DNA as a probe, Southern blotting analysis confirmed the products originatedfrom Ag. intermedium genome. The products were purified, ligated to pUC18 and then transformedinto competence E.coli DH5αto produce a 2Ai-2 chromosome DNA library. The microcloningexperiments produced approximately 5 ×105 clones, the size range of the cloned inserts was 200-1 500 bp, with an average of 580 bp. Using Ag.intermedium genomic DNA as a probe, dot blottingresults showed that 56% clones are unique/low copy sequences, 44% are repetitive sequences inthe library. Four Ag. intermedium clones were screened from the library by RFLP, and threeclones(Mag065, Mag088, Mag139)belong to low/single sequences, one clone(Mag104)was repetitivesequence, and GISH results indicated that Mag104 was Ag.intermedium species-specific repetitiveDNA sequence.展开更多
The present study deals with colonization potential of plant growth promoting bacterial strains (Ochrobactrum intermedium, Bacillus cereus and Brevibacterium sp.) on Vigna radiata roots. The roots were heavily coloniz...The present study deals with colonization potential of plant growth promoting bacterial strains (Ochrobactrum intermedium, Bacillus cereus and Brevibacterium sp.) on Vigna radiata roots. The roots were heavily colonized with O. intermedium and B. cereus as compared to Brevibacterium sp. O. intermedium mainly colonized rhizoplane while B. cereus occurred both on the rhizoplane and near root zone. O. intermedium and B. cereus were found to be present both on the rhizoplane and near root zone, while Brevibacterium only in the rhizosphere in the form of groups. The cells of B. cereus were found more in the sites where root exudates were existed. From the above results it was observed that the number of O. intermedium cells were large at root exudate site. Fig 2, Tab 1, Ref展开更多
Thinopyrum ponticum and Th. intermedium provide superior resistance against various diseases in wheat (Ttricum aestivum). Because of their readily crossing with wheat, many genes for disease resistance have been int...Thinopyrum ponticum and Th. intermedium provide superior resistance against various diseases in wheat (Ttricum aestivum). Because of their readily crossing with wheat, many genes for disease resistance have been introduced from the wheatgrasses into wheat. Genes for resistance to leaf rust, stem rust, powdery mildew, Barley yellow dwarf virus, Wheat streak mosaic virus, and its vector, the wheat curl mite, have been transferred into wheat by producing chromosome translocations. These genes offer an opportunity to improve resistance of wheat to the diseases; some of them have been extensively used in protecting wheat from damage of the diseases. Moreover, new resistance to diseases is continuously detected in the progenies of wheat-Thinopyrum derivatives. The present article summaries characterization and application of the genes for fungal and viral disease-resistance derived from Th. ponticum and Th. intermedium.展开更多
The wheat line H960642 is a homozygous wheat-Thinopyrum intermedium translocation line with resistance to BYDV by genomie in situ hybridization (GISH) and RFLP analysis. The genomie DNA of Th. intermedium was used as ...The wheat line H960642 is a homozygous wheat-Thinopyrum intermedium translocation line with resistance to BYDV by genomie in situ hybridization (GISH) and RFLP analysis. The genomie DNA of Th. intermedium was used as a probe, and eonunon wheat genomie DNA as a blocking in GISH experiment. The results showed that the chromosome segments of Th. intermedium were transferred to the distal end of a pair of wheat chromosomes. RFLP analysis indicated that the transloeation line H960642 is a T7DS·7DL-7XL translocation by using 8 probes mapped on the homoeologous group 7 in wheat. The tranalocation breakpoint is located between Xpsr680 and Xpsr965 about 90—99 cM from the centromere. The RFLP markers psr680 and psr687 were closoly linked with the BYDV resistance gene. The gene is located on the distal end of 7XL around Xpsr680 and Xpsr687.展开更多
Wheat-related species Th. intermedium was used to cross with common wheat Yannong 15. In the self progenies of the hybrid, two addition lines, II -1-7-1 and II -3-3-2, stable in cytology, were developed by cytology an...Wheat-related species Th. intermedium was used to cross with common wheat Yannong 15. In the self progenies of the hybrid, two addition lines, II -1-7-1 and II -3-3-2, stable in cytology, were developed by cytology and powdery mildew resistance identification. Their chromosome number were 2n = 44 and formed 22 bivalents at PMC MI. In F1 of the two addition lines crossing with Yannong 15, there appeared about one univalent at PMC MI, respectively. Resistance identification in greenhouse and field using the No. 15 and mixed strains of E. gramnis f. sp. tritici showed that they were immune to powdery mildew. Chromosome number and resistance identification using the F2 single plants of the addition line crossing with Yannong 15 indicated that the resistant gene was located on the alien chromosomes. In situ hybridization using St and E genomic DNA as probe showed that the added chromosome in the two addition lines probably came from the E genome of Th. intermedium, which indicated that a pair of E genome展开更多
: Wide cross and molecular cytogenetic methods were used to transfer the powdery mildew resistance gene from Thinopyron intermedium(Host) Barkworth & DR Dewey to wheat. Among the progeny of crossing common wheat (...: Wide cross and molecular cytogenetic methods were used to transfer the powdery mildew resistance gene from Thinopyron intermedium(Host) Barkworth & DR Dewey to wheat. Among the progeny of crossing common wheat (Triticum aestivum L.) Yannong 15 with Th. intermedium, a partial amphiploid E990256, with resistance to powdery mildew, was developed. It had 56 chromosomes and could form 28 bivalents in pollen mother cells at metaphase I of meiosis. Resistance verification by race 15 at the seedling stage and by mixed strains of Erysiphales gramnis DC. f. sp. tritici Em. Marchal at the adult stage showed it was immune to powdery mildew at both stages. Gene postulation via 21 isolates of E. gramnis f. sp. tritici and 29 differential hosts showed it was nearly immune to all the isolates used, and its resistance pattern was different from all the mildew resistance genes used, which indicated it probably contained a new resistance gene to powdery mildew. Biochemical verification showed it might convey different Th. intermedium chromosomes from those of the wheat- Th. intermedium partial amphiploids Zhong 1–5. Genomic in situ hybridization analysis by using St genomic DNA as the probe showed E990256 contained a recombination genome of St and E.展开更多
As a staple food crop for one-third of the world's population, common wheat (Triticum aestivum L., 2n = 6x = 42, AABBDD) plays an important role in humans' food security. However, the genetic variation of cultivat...As a staple food crop for one-third of the world's population, common wheat (Triticum aestivum L., 2n = 6x = 42, AABBDD) plays an important role in humans' food security. However, the genetic variation of cultivated wheat has been dramatically narrowed by genetic erosion under the modem cultivation system, resulting in vulnerability to biotic and abiotic stresses (Jiang et al., 1994; Friebe et al., 1996). The wild relatives of wheat represent a large reservoir of superior genes, and transferring these alien genes to modem cultivars through chromosome engineering is a successful method of broadening the genetic diversity of wheat (Chen et al., 2003;展开更多
In this study, we isolated an environmental clone of Ochrobactrum intermedium, strain 2745-2, from the formation water of Changqing oilfield in Shanxi, China, which can degrade crude oil. Strain 2745-2 is aerobic and ...In this study, we isolated an environmental clone of Ochrobactrum intermedium, strain 2745-2, from the formation water of Changqing oilfield in Shanxi, China, which can degrade crude oil. Strain 2745-2 is aerobic and rod-shaped with optimum growth at 42 ℃ and pH 5.5. We sequenced the genome and found a single chromosome of 4800175 bp, with a G+C content of 57.63%. Sixty RNAs and 4737 protein-coding genes were identified: many of the genes are responsible for the degradation, emulsification, and metabolizing of crude oil. A comparative genomic analysis with related clinical strains (M86, 229E, and LMG3301T) showed that genes involved in virulence, disease, defense, phages, prophages, transposable elements, plasmids, and antibiotic resistance are also present in strain 2745-2.展开更多
Wide hybridization is an effective approach for enhancing the resistance of bread wheat (Triticum aestivum L.) to biotic and abiotic stresses by introducing favorable alien genes (Sepsi et al., 2008). Wheatgrass, ...Wide hybridization is an effective approach for enhancing the resistance of bread wheat (Triticum aestivum L.) to biotic and abiotic stresses by introducing favorable alien genes (Sepsi et al., 2008). Wheatgrass, Thinopyrum intermedium (Host) Barkworth & D.R. Dewey or Agropyron intermedium (Host) Beauvoir (2n = 42; genome formula JJjSjSstst), is a perennial species in the tribe Triticeae and an important source of wheat improvement for biotic and abiotic stress resistance and quality-related traits, such as high grain protein concentration (Chen et al., 1998; 2001; 2003; Han et al., 2004; Li and Wang, 2009). In addition, the ready crossing ability of wheatgrass with various Triticum species has made it popular in germ- plasm development.展开更多
Stripe rust,caused by Puccinia striformis f.sp.tritici(Pst),is one of the most destructive diseases of wheat(Triticum aestivum L)worldwide.Xiaoyan 78829,a partial amphidiploid developed by crossing common wheat with T...Stripe rust,caused by Puccinia striformis f.sp.tritici(Pst),is one of the most destructive diseases of wheat(Triticum aestivum L)worldwide.Xiaoyan 78829,a partial amphidiploid developed by crossing common wheat with Thinopyrum intermedium,is immune to wheat stripe rust.To transfer the resis-tance gene of this excellent germplasm resource to wheat,the tr anslocation line WTT11 was produced by pollen irradiation and assessed for immunity to stripe rust races CYR32,CYR33 and CYR34.A novel stripe rust-resistance locus derived from Th.intermedium was confirmed by linkage and diagnostic marker analyses.Molecular cytogenetic analyses revealed that WTT11 carries a TTh 2DL translocation.The breakpoint of 1B was located at 95.5 MB,and the alien segments were found to be homoeologous to wheat-group chromosomes 6 and 7 according to a wheat660K single-nucleotide polymorphism(SNP)array analysis.Ten previously developed PCR-based markers were confirmed to rapidly trace the alien segments of WTT11,and 20 kompetitive allele-specific PCR(KASP)markers were developed to enable genotyping of Th.intermedium and common wheat.Evaluation of agronomic traits in two consecutive crop seasons uncovered some favorable agronomic traits in WTT11,such as lower plant height and longer main panicles,that may be applicable to wheat improvement.As a novel genetic resource,the new resistance locus may be useful for wheat disease-resistance breeding.展开更多
文摘The wheat_ Thinopyrum intermedium addition lines Z1,Z2 contain a pair of Th. intermedium chromosomes 2Ai_2 carrying the gene with resistance to barley yellow dwarf virus (BYDV). Genomic in situ hybridization (GISH) was used to analyze the chromosome constitution of Z1,Z2 by using genomic DNA probes from Th. intermedium and Pseudoroegneria strigosa . The results showed that the chromosome constitution of either Z1 or Z2 composes of 42 wheat chromosomes and two Th. intermedium chromosomes (2Ai_2). The 2Ai_2 chromosome is St_E intercalary translocation, in which the E genomic chromosome segment translocated into the middle region of the long arm of chromosome belonging to St genome. With the genomic DNA probe of Ps. strigosa , the GISH pattern specific to the 2Ai_2 chromosome may be used as a molecular cytogenetic marker. A detailed RFLP analysis on Z1, Z2 and their parents was carried out by using 12 probes on the wheat group 2 chromosomes. Twenty RFLP markers specific to the 2Ai_2 chromosome were identified. Two RAPD markers of OPR16 -350 and OPH09 -1580 , specific to the 2Ai_2 chromosome, were identified from 280 RAPD primers. These molecular markers could be used to assisted_select translocation lines with small segment of the 2Ai_2 chromosome and provide tools to localize the BYDV resistance.
基金supported by the National Natural Science Foundation of China (30571156)
文摘The wheatgrass, Thinopyrum intermedium (Host) Barkworth & DR Dewey, shows many beneficial characteristics, such as big spikes and high resistance to many diseases. To transfer the beneficial genes of this species, many wheat- Thinopyrum intermedium alien chromosome lines were developed. Of them, Shannong 0095 (SN0095), a disomic substitution, has long spikes and flag-leaves, and thus may be an important genetic resource for wheat yield improvement. In order to realize its heterosis and combining ability on major yield traits, a 7 ×7 complete diallel design was made according to Griffing's Method-1. The results showed that heterosis for spike length (SPL), flag-leaf area (FLA), number of spikes per plant (NSP), number of spikelets per spike (NSL), kernels per spike (KPS), 1 000-kernel weight (TKW) and grain yield per plant (GYP) existed in all the crosses by SN0095, but heterobeltiosis occurred only for KPS, TKW, and GYP. The relative mid-parent heterosis (RMH) and relative high-parent heterosis (RHH) for GYP, which valued as high as 35.32 and 29.92% respectively, were the highest among all the traits mearsured. Though additive and non-additive gene effects and cytoplasmic effects (or cytoplasmic-nuclear interaction effects) were found in governing all the traits measured above, additive gene action played a predominant role. The results also showed that SN0095 was the best-general combiner for SPL and FLA, and high-general combiner for NSP amongst all the parents. Estimates of specific combining ability (SCA) showed that SN0095 could also make high-SCA combinations for GYP, such as SN0095 × Jimai 19 (JMI9). SN0095 could be a unique and important parent in hybrid wheat breeding programs.
基金supported by the National Key Research and Development Program of China(2016YFD0102000)National Natural Science Foundation of China(31671675)Natural Science Foundation of Shandong Province(ZR2015CM034 and ZR2016CM30)。
文摘Thinopyrum intermedium has been used as a resource for improving resistance to biotic and abiotic stresses and yield potential in common wheat. Wheat line SN304 was derived from a cross between common wheat cultivar Yannong 15 and Th. intermedium. Genomic in situ hybridization(GISH) produced no hybridization signal in SN304 using Th. intermedium genomic DNA as a probe, but fluorescence in situ hybridization(FISH) using oligonucleotides AFA-3, AFA-4, pAs1-1, pAs1-3, pAs1-4, pAs1-6, pSc119.2-1,and(GAA)10 as probes detected hybridization signals on chromosomes 2 A, 7 A, 2 B, 3 B, 6 B, and 7 B in SN304 that differed from Yannong 15. Results of specific markers also indicated that there were Th. intermedium chromatin introgressions on different chromosomes in SN304. In a hydroponic culture experiment, SN304 not only produced more biomass and higher stem and leaf dry weight but also accumulated more phosphorus than Yannong 15 under phosphorus-deficiency stress. Moreover, SN304 produced a lower pH and released more organic acids, especially oxalic acid, than Yannong 15, which suggests that SN304 exudates enabled more absorbance of P than Yannong 15 under comparable conditions.The results indicate that SN304 is a wheat-Th. intermedium introgression line with tolerance to phosphorus-deficiency stress.
基金supported by National High-Tech R&D(863)ProgramNational Natural Science Foundation of China(101-04-03-03-97).
文摘The univalent from the meiosis-metaphase spreads of F1 (Z2× wheat variety Wan7107) wasidentified to be Agropyrum intermedium 2Ai-2 chromosome by GISH. The 2Ai-2 chromosomes weremicroisolated and collected. After two rounds of PCR amplification, the PCR products wereranged from 150-3 000 bp,with predominant fragments at about 200-2 000 bp. Using Ag.intermedium genomic DNA as a probe, Southern blotting analysis confirmed the products originatedfrom Ag. intermedium genome. The products were purified, ligated to pUC18 and then transformedinto competence E.coli DH5αto produce a 2Ai-2 chromosome DNA library. The microcloningexperiments produced approximately 5 ×105 clones, the size range of the cloned inserts was 200-1 500 bp, with an average of 580 bp. Using Ag.intermedium genomic DNA as a probe, dot blottingresults showed that 56% clones are unique/low copy sequences, 44% are repetitive sequences inthe library. Four Ag. intermedium clones were screened from the library by RFLP, and threeclones(Mag065, Mag088, Mag139)belong to low/single sequences, one clone(Mag104)was repetitivesequence, and GISH results indicated that Mag104 was Ag.intermedium species-specific repetitiveDNA sequence.
文摘The present study deals with colonization potential of plant growth promoting bacterial strains (Ochrobactrum intermedium, Bacillus cereus and Brevibacterium sp.) on Vigna radiata roots. The roots were heavily colonized with O. intermedium and B. cereus as compared to Brevibacterium sp. O. intermedium mainly colonized rhizoplane while B. cereus occurred both on the rhizoplane and near root zone. O. intermedium and B. cereus were found to be present both on the rhizoplane and near root zone, while Brevibacterium only in the rhizosphere in the form of groups. The cells of B. cereus were found more in the sites where root exudates were existed. From the above results it was observed that the number of O. intermedium cells were large at root exudate site. Fig 2, Tab 1, Ref
基金supported by the Ministry of Agriculture of China (No. NB08-2130135-(25-30)-21)
文摘Thinopyrum ponticum and Th. intermedium provide superior resistance against various diseases in wheat (Ttricum aestivum). Because of their readily crossing with wheat, many genes for disease resistance have been introduced from the wheatgrasses into wheat. Genes for resistance to leaf rust, stem rust, powdery mildew, Barley yellow dwarf virus, Wheat streak mosaic virus, and its vector, the wheat curl mite, have been transferred into wheat by producing chromosome translocations. These genes offer an opportunity to improve resistance of wheat to the diseases; some of them have been extensively used in protecting wheat from damage of the diseases. Moreover, new resistance to diseases is continuously detected in the progenies of wheat-Thinopyrum derivatives. The present article summaries characterization and application of the genes for fungal and viral disease-resistance derived from Th. ponticum and Th. intermedium.
基金Project supported by the 863 program and the National Natural Science Foundation of China (Grant No. 39680027).
文摘The wheat line H960642 is a homozygous wheat-Thinopyrum intermedium translocation line with resistance to BYDV by genomie in situ hybridization (GISH) and RFLP analysis. The genomie DNA of Th. intermedium was used as a probe, and eonunon wheat genomie DNA as a blocking in GISH experiment. The results showed that the chromosome segments of Th. intermedium were transferred to the distal end of a pair of wheat chromosomes. RFLP analysis indicated that the transloeation line H960642 is a T7DS·7DL-7XL translocation by using 8 probes mapped on the homoeologous group 7 in wheat. The tranalocation breakpoint is located between Xpsr680 and Xpsr965 about 90—99 cM from the centromere. The RFLP markers psr680 and psr687 were closoly linked with the BYDV resistance gene. The gene is located on the distal end of 7XL around Xpsr680 and Xpsr687.
基金This work was supported by the National Natural Science Foundation of China (Grant No.39970458)。
文摘Wheat-related species Th. intermedium was used to cross with common wheat Yannong 15. In the self progenies of the hybrid, two addition lines, II -1-7-1 and II -3-3-2, stable in cytology, were developed by cytology and powdery mildew resistance identification. Their chromosome number were 2n = 44 and formed 22 bivalents at PMC MI. In F1 of the two addition lines crossing with Yannong 15, there appeared about one univalent at PMC MI, respectively. Resistance identification in greenhouse and field using the No. 15 and mixed strains of E. gramnis f. sp. tritici showed that they were immune to powdery mildew. Chromosome number and resistance identification using the F2 single plants of the addition line crossing with Yannong 15 indicated that the resistant gene was located on the alien chromosomes. In situ hybridization using St and E genomic DNA as probe showed that the added chromosome in the two addition lines probably came from the E genome of Th. intermedium, which indicated that a pair of E genome
文摘: Wide cross and molecular cytogenetic methods were used to transfer the powdery mildew resistance gene from Thinopyron intermedium(Host) Barkworth & DR Dewey to wheat. Among the progeny of crossing common wheat (Triticum aestivum L.) Yannong 15 with Th. intermedium, a partial amphiploid E990256, with resistance to powdery mildew, was developed. It had 56 chromosomes and could form 28 bivalents in pollen mother cells at metaphase I of meiosis. Resistance verification by race 15 at the seedling stage and by mixed strains of Erysiphales gramnis DC. f. sp. tritici Em. Marchal at the adult stage showed it was immune to powdery mildew at both stages. Gene postulation via 21 isolates of E. gramnis f. sp. tritici and 29 differential hosts showed it was nearly immune to all the isolates used, and its resistance pattern was different from all the mildew resistance genes used, which indicated it probably contained a new resistance gene to powdery mildew. Biochemical verification showed it might convey different Th. intermedium chromosomes from those of the wheat- Th. intermedium partial amphiploids Zhong 1–5. Genomic in situ hybridization analysis by using St genomic DNA as the probe showed E990256 contained a recombination genome of St and E.
基金supported by a grant from the National High Technology Research and Development Program("863" Program) of China(No. 2011AA100103)
文摘As a staple food crop for one-third of the world's population, common wheat (Triticum aestivum L., 2n = 6x = 42, AABBDD) plays an important role in humans' food security. However, the genetic variation of cultivated wheat has been dramatically narrowed by genetic erosion under the modem cultivation system, resulting in vulnerability to biotic and abiotic stresses (Jiang et al., 1994; Friebe et al., 1996). The wild relatives of wheat represent a large reservoir of superior genes, and transferring these alien genes to modem cultivars through chromosome engineering is a successful method of broadening the genetic diversity of wheat (Chen et al., 2003;
基金supported by the National High-Tech R&D Program(863)of China(No.2013AA064402)the National Natural Science Foundation of China(Nos.81301461 and 51474034)+1 种基金the Zhejiang Provincial Natural Science Foundation of China(No.LQ13H190002)the Scientific Research Foundation of Zhejiang Provincial Health Bureau(No.2012KYB083),China
文摘In this study, we isolated an environmental clone of Ochrobactrum intermedium, strain 2745-2, from the formation water of Changqing oilfield in Shanxi, China, which can degrade crude oil. Strain 2745-2 is aerobic and rod-shaped with optimum growth at 42 ℃ and pH 5.5. We sequenced the genome and found a single chromosome of 4800175 bp, with a G+C content of 57.63%. Sixty RNAs and 4737 protein-coding genes were identified: many of the genes are responsible for the degradation, emulsification, and metabolizing of crude oil. A comparative genomic analysis with related clinical strains (M86, 229E, and LMG3301T) showed that genes involved in virulence, disease, defense, phages, prophages, transposable elements, plasmids, and antibiotic resistance are also present in strain 2745-2.
基金supported by the Provincial Prize Fund for Distinguished Young and Middle-aged Scientists of Shandong Province(No.BS2011SW053)State Key Laboratory of Plant Cell and Chromosome Engineering(No.PCCE-KF-2014-01)State Key Laboratory of Crop Biology(No.2015KF06)
文摘Wide hybridization is an effective approach for enhancing the resistance of bread wheat (Triticum aestivum L.) to biotic and abiotic stresses by introducing favorable alien genes (Sepsi et al., 2008). Wheatgrass, Thinopyrum intermedium (Host) Barkworth & D.R. Dewey or Agropyron intermedium (Host) Beauvoir (2n = 42; genome formula JJjSjSstst), is a perennial species in the tribe Triticeae and an important source of wheat improvement for biotic and abiotic stress resistance and quality-related traits, such as high grain protein concentration (Chen et al., 1998; 2001; 2003; Han et al., 2004; Li and Wang, 2009). In addition, the ready crossing ability of wheatgrass with various Triticum species has made it popular in germ- plasm development.
基金the National Key Research and Development Pro-gram of China(2016YFD0102000)the National Natural Sci-ence Foundation of China(no.31971875).
文摘Stripe rust,caused by Puccinia striformis f.sp.tritici(Pst),is one of the most destructive diseases of wheat(Triticum aestivum L)worldwide.Xiaoyan 78829,a partial amphidiploid developed by crossing common wheat with Thinopyrum intermedium,is immune to wheat stripe rust.To transfer the resis-tance gene of this excellent germplasm resource to wheat,the tr anslocation line WTT11 was produced by pollen irradiation and assessed for immunity to stripe rust races CYR32,CYR33 and CYR34.A novel stripe rust-resistance locus derived from Th.intermedium was confirmed by linkage and diagnostic marker analyses.Molecular cytogenetic analyses revealed that WTT11 carries a TTh 2DL translocation.The breakpoint of 1B was located at 95.5 MB,and the alien segments were found to be homoeologous to wheat-group chromosomes 6 and 7 according to a wheat660K single-nucleotide polymorphism(SNP)array analysis.Ten previously developed PCR-based markers were confirmed to rapidly trace the alien segments of WTT11,and 20 kompetitive allele-specific PCR(KASP)markers were developed to enable genotyping of Th.intermedium and common wheat.Evaluation of agronomic traits in two consecutive crop seasons uncovered some favorable agronomic traits in WTT11,such as lower plant height and longer main panicles,that may be applicable to wheat improvement.As a novel genetic resource,the new resistance locus may be useful for wheat disease-resistance breeding.