Seed viability of 18 576 accessions of 23 crops was monitored. After 10-12 years storage in National Crop Genebank ofChina (NCGC), more than 96.12% of the accessions maintained high germination percentage (>85%). T...Seed viability of 18 576 accessions of 23 crops was monitored. After 10-12 years storage in National Crop Genebank ofChina (NCGC), more than 96.12% of the accessions maintained high germination percentage (>85%). The germination of95 accessions, accounting for 0.51% of the total, declined significantly from above 80% to below 70%. For each crop ofcarrot (Daucus carota var. sativa DC.), lettuce (Lactuca sativa L.), cotton (Gossypium sp. L.), flax (Linum usitatissimumL.) and castor-oil plant (Ricinus communis L.), the mean monitored germination percentage declined significantly as awhole, of which carrot and lettuce seeds lost viability more rapidly. Seed initial germination percentage and pre-storageenvironments affect subsequent seed viability in storage.展开更多
Fluorescent in situ hybridization (FISH) was used to investigate the chromosomal location of 18S-5.8S-26S rDNA loci in Thinopyrum intermedium (Host) Barkworth et Dewey (2n=6x=42). In all accessions and individuals stu...Fluorescent in situ hybridization (FISH) was used to investigate the chromosomal location of 18S-5.8S-26S rDNA loci in Thinopyrum intermedium (Host) Barkworth et Dewey (2n=6x=42). In all accessions and individuals studied, 3 or 4 pairs of major loci were detected. Subsequent genomic in situhybddization (GISH) analyses revealed that one pair was located on the ends of the short arms of one pair of homologous chromosomes of the St genome, while the other 2 or 3 pairs of major loci were located in the E genomes (including the E^o and E^b). It is suggested that 2 to 3 pairs of major loci were probably lost during the evolution of this hexaploid species. The variation in rDNA positions and copy numbers between the diploid donors and Th. interrnedium, as well as the diversity among the accessions of Th. intermedium confirmed that the rDNA gene family conveyed the characters of DNA mobile elements. The internal transcribed spacer (ITS) regions of the rDNA in Th. intermedium were also investigated. Sequence data of seven positive clones from one individual suggested high degree of individual heterogeneity exists among ITS repeats. Phylogenetic analyses showed that there were two distinct types of ITS sequences in Th. intermedium, one with homology to that of Pseudoroegneria species (St genome) and the other to that of the E genome diploid species. This showed that the ITS paralogues in Th. intermedium have not been uniformly homogenized by concerted evolution. The limitation of using the chromosomal location of rDNA loci for phylogenetic analysis is discussed.展开更多
The investigation of rice varieties stability for amylose content (AC), gelatinization temperature (GT) and protein content (PC) was carried out using additive main effects and multiplicative interaction (AMMI) model ...The investigation of rice varieties stability for amylose content (AC), gelatinization temperature (GT) and protein content (PC) was carried out using additive main effects and multiplicative interaction (AMMI) model in three locations and two years. Eighteen tested varieties were further clustered and evaluated based on the phenotypic values of three quality traits and their Di values from the AMMI analysis. The results showed that the genotype by environment interactions, the differences of phenotype and stability of AC, GT and PC among different genotypes and environments were all significant at 1% level. Also, only one variety, W002, had high stability for all the three quality traits. Additionally, in consideration with the phenotype of AC, GT and PC, and their stability in rice varieties, etc., four rice varieties, W002, Zaofeng 9, Guangling Xiangjing and Nanjing16, could be also applied as breeding parents to improve eating quality and stability of rice.展开更多
Ethylene receptors play important roles not only in regulation of growth and development but also in response to environmental stimuli of plants. However, there are few reports on ethylene receptors in soybean. In thi...Ethylene receptors play important roles not only in regulation of growth and development but also in response to environmental stimuli of plants. However, there are few reports on ethylene receptors in soybean. In this article, putative ethylene receptors of soybean were searched from soybean genomic database （http：//www.phytozome.net/search.php） and analyzed. The ethylene receptor gene family in soybean comprising eight members, designated as GmERSI-1, GmERS1-2, GmETRI-1, GmETR1-2, GmETR2-1, GmETR2-2, GmEIN4-1, and GmEIN4-2 corresponding with their homologous genes in drabidopsis, were isolated and analyzed. Phylogenetic analysis indicated that the eight soybean ethylene receptors （SERs） were in two subfamilies and further divided into four groups, viz., groups I （GmERSI-1 and GmERS1-2）, 1I （GmETRI-1 and GmETR1-2）, VI （GmETR2-I and GmETR2-2）, and VII （GmEIN4-1 and GmEIN4-2）. Protein structure of the members in groups I and II from subfamily I were more conserved than the members in other two groups from subfamily II. Expression patterns of the SERs were compared with the homologous genes in Arabidopsis. The results demonstrated that expression patterns of the SERs differed from Arabidopsis members in the same group, suggesting that SERs are involved in different signal pathways compared to ethylene receptors in drabidopsis. Promoter analysis showed that the sequences of the members in each group were different from each other, and some specific binding elements of transcription factors detected in promoter sequences might explain the differences between the members in the same group. A novel soybean TPR protein （tetratricopeptide repeat protein）, GmTPR, was identified to interact with GmETRI-1, apparently an important ethylene receptor in ethylene signaling pathway in soybean. This suggested that GmTPR might be a novel downstream component of the ethylene signaling pathway.展开更多
: The genetic diversity and genetic structure of a population of isolates of Sclerotinia sclerotiorum (Lib.) de Bary from different regions and host plants were investigated using the random amplified polymorphic DNA ...: The genetic diversity and genetic structure of a population of isolates of Sclerotinia sclerotiorum (Lib.) de Bary from different regions and host plants were investigated using the random amplified polymorphic DNA (RAPD) method with 20 random decamer primer pairs in order to provide some information on the phylogenetic taxa and breeding for resistance to sclerotinia stem rot. A minimum of three and a maximum of 15 unambiguously amplified bands were generated, furnishing a total of 170 bands ranging in size from 100 to 3 200 bp, corresponding to an average of 8.5 bands per primer pair. One hundred and four of these 170 bands (61.2%) were polymorphic, the percentage of polymorphic bands for each primer pair ranging from 0.0% to 86.7%. The genetic relationships among the isolates, based on the results of RAPD analysis, were examined. The genetic similarity of all selected isolates was quite high. At the species level, the genetic diversity estimated by Nei's gene diversity (h) was 0.197 and Shannon's index of diversity (I) was 0.300. The unweighted pair-group mean analysis (UPGMA) cluster analysis showed that most isolates from the same regions were grouped in the same cluster or a close cluster. The population of isolates from Hefei (Anhui Province, China) was more uniform and relatively distant to other populations. The Canadian population collected from carrot (Daucus carota var. sativa DC.) was relatively close to the Polish population collected from oilseed rape (Brassica napus L.) plants. There was no relationship between isolates from the same host plants. An analysis of molecular variance (AMOVA) revealed that the percentage of variance attributable to variation among and within populations was 50.62% and 49.38%, respectively. When accessions from China, Europe, and Canada were treated as three separate groups, the variance components among groups, among populations within groups, and within populations were ?0.96%, 51.48%, and 49.47%, respectively. The genetic differentiations among and within populations were highly significant (P < 0.001). Similarly, the coefficient of gene differentiation (Gst) in total populations calculated by population genetic analysis was 0.229 4, which indicated that the genetic variation among populations was 22.94%. The gene flow (Nm) was 1.68, which indicated that the gene permutation and interaction among populations was relatively high.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
文摘Seed viability of 18 576 accessions of 23 crops was monitored. After 10-12 years storage in National Crop Genebank ofChina (NCGC), more than 96.12% of the accessions maintained high germination percentage (>85%). The germination of95 accessions, accounting for 0.51% of the total, declined significantly from above 80% to below 70%. For each crop ofcarrot (Daucus carota var. sativa DC.), lettuce (Lactuca sativa L.), cotton (Gossypium sp. L.), flax (Linum usitatissimumL.) and castor-oil plant (Ricinus communis L.), the mean monitored germination percentage declined significantly as awhole, of which carrot and lettuce seeds lost viability more rapidly. Seed initial germination percentage and pre-storageenvironments affect subsequent seed viability in storage.
文摘Fluorescent in situ hybridization (FISH) was used to investigate the chromosomal location of 18S-5.8S-26S rDNA loci in Thinopyrum intermedium (Host) Barkworth et Dewey (2n=6x=42). In all accessions and individuals studied, 3 or 4 pairs of major loci were detected. Subsequent genomic in situhybddization (GISH) analyses revealed that one pair was located on the ends of the short arms of one pair of homologous chromosomes of the St genome, while the other 2 or 3 pairs of major loci were located in the E genomes (including the E^o and E^b). It is suggested that 2 to 3 pairs of major loci were probably lost during the evolution of this hexaploid species. The variation in rDNA positions and copy numbers between the diploid donors and Th. interrnedium, as well as the diversity among the accessions of Th. intermedium confirmed that the rDNA gene family conveyed the characters of DNA mobile elements. The internal transcribed spacer (ITS) regions of the rDNA in Th. intermedium were also investigated. Sequence data of seven positive clones from one individual suggested high degree of individual heterogeneity exists among ITS repeats. Phylogenetic analyses showed that there were two distinct types of ITS sequences in Th. intermedium, one with homology to that of Pseudoroegneria species (St genome) and the other to that of the E genome diploid species. This showed that the ITS paralogues in Th. intermedium have not been uniformly homogenized by concerted evolution. The limitation of using the chromosomal location of rDNA loci for phylogenetic analysis is discussed.
基金The project was supported by the National 863 Program(2003AA222131 and 2003AA207020)the National Natural Science Foundation of China(30270811)+1 种基金the National Science and Technology Achievements Spreading Program(02EFN213200232)Jiangsu Science and Technology Development Program,China(BE 2001305).
文摘The investigation of rice varieties stability for amylose content (AC), gelatinization temperature (GT) and protein content (PC) was carried out using additive main effects and multiplicative interaction (AMMI) model in three locations and two years. Eighteen tested varieties were further clustered and evaluated based on the phenotypic values of three quality traits and their Di values from the AMMI analysis. The results showed that the genotype by environment interactions, the differences of phenotype and stability of AC, GT and PC among different genotypes and environments were all significant at 1% level. Also, only one variety, W002, had high stability for all the three quality traits. Additionally, in consideration with the phenotype of AC, GT and PC, and their stability in rice varieties, etc., four rice varieties, W002, Zaofeng 9, Guangling Xiangjing and Nanjing16, could be also applied as breeding parents to improve eating quality and stability of rice.
基金funded in part by the National Key Project for Research on Transgenic Biology (2011ZX08002-002 and 2011ZX08002-005)the National High-Tech R&D Program of China (2012AA10A309)
文摘Ethylene receptors play important roles not only in regulation of growth and development but also in response to environmental stimuli of plants. However, there are few reports on ethylene receptors in soybean. In this article, putative ethylene receptors of soybean were searched from soybean genomic database （http：//www.phytozome.net/search.php） and analyzed. The ethylene receptor gene family in soybean comprising eight members, designated as GmERSI-1, GmERS1-2, GmETRI-1, GmETR1-2, GmETR2-1, GmETR2-2, GmEIN4-1, and GmEIN4-2 corresponding with their homologous genes in drabidopsis, were isolated and analyzed. Phylogenetic analysis indicated that the eight soybean ethylene receptors （SERs） were in two subfamilies and further divided into four groups, viz., groups I （GmERSI-1 and GmERS1-2）, 1I （GmETRI-1 and GmETR1-2）, VI （GmETR2-I and GmETR2-2）, and VII （GmEIN4-1 and GmEIN4-2）. Protein structure of the members in groups I and II from subfamily I were more conserved than the members in other two groups from subfamily II. Expression patterns of the SERs were compared with the homologous genes in Arabidopsis. The results demonstrated that expression patterns of the SERs differed from Arabidopsis members in the same group, suggesting that SERs are involved in different signal pathways compared to ethylene receptors in drabidopsis. Promoter analysis showed that the sequences of the members in each group were different from each other, and some specific binding elements of transcription factors detected in promoter sequences might explain the differences between the members in the same group. A novel soybean TPR protein （tetratricopeptide repeat protein）, GmTPR, was identified to interact with GmETRI-1, apparently an important ethylene receptor in ethylene signaling pathway in soybean. This suggested that GmTPR might be a novel downstream component of the ethylene signaling pathway.
基金Basic Research and Development Plan of China，国家科技攻关项目，the Sino-Polish Scientific and Technological Cooperation Project for 2004-2006，中国科学院资助项目
文摘: The genetic diversity and genetic structure of a population of isolates of Sclerotinia sclerotiorum (Lib.) de Bary from different regions and host plants were investigated using the random amplified polymorphic DNA (RAPD) method with 20 random decamer primer pairs in order to provide some information on the phylogenetic taxa and breeding for resistance to sclerotinia stem rot. A minimum of three and a maximum of 15 unambiguously amplified bands were generated, furnishing a total of 170 bands ranging in size from 100 to 3 200 bp, corresponding to an average of 8.5 bands per primer pair. One hundred and four of these 170 bands (61.2%) were polymorphic, the percentage of polymorphic bands for each primer pair ranging from 0.0% to 86.7%. The genetic relationships among the isolates, based on the results of RAPD analysis, were examined. The genetic similarity of all selected isolates was quite high. At the species level, the genetic diversity estimated by Nei's gene diversity (h) was 0.197 and Shannon's index of diversity (I) was 0.300. The unweighted pair-group mean analysis (UPGMA) cluster analysis showed that most isolates from the same regions were grouped in the same cluster or a close cluster. The population of isolates from Hefei (Anhui Province, China) was more uniform and relatively distant to other populations. The Canadian population collected from carrot (Daucus carota var. sativa DC.) was relatively close to the Polish population collected from oilseed rape (Brassica napus L.) plants. There was no relationship between isolates from the same host plants. An analysis of molecular variance (AMOVA) revealed that the percentage of variance attributable to variation among and within populations was 50.62% and 49.38%, respectively. When accessions from China, Europe, and Canada were treated as three separate groups, the variance components among groups, among populations within groups, and within populations were ?0.96%, 51.48%, and 49.47%, respectively. The genetic differentiations among and within populations were highly significant (P < 0.001). Similarly, the coefficient of gene differentiation (Gst) in total populations calculated by population genetic analysis was 0.229 4, which indicated that the genetic variation among populations was 22.94%. The gene flow (Nm) was 1.68, which indicated that the gene permutation and interaction among populations was relatively high.
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.
