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1.
Geographic distribution and multilocus organization of isozyme variation of rice (Oryza sativa L.) 总被引:5,自引:0,他引:5
Z. Li J. N. Rutger 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,101(3):379-387
Genetic organization of isozyme variation in rice (Oryza sativa L.) was investigated based on 17 polymorphic isozyme loci using a sample of 511 accessions of worldwide origin. The genetic
diversity within the species was very high (H=0.36 with 4.82 alleles per locus), as compared with most selfing plant species.
Three diversity centers were detected for isozyme variation including South Asia, China and Southeast Asia. The accessions
were classified into three well-differentiated cultivar groups corresponding to the indica and japonica subspecies, and a new unnamed group. Variation within the cultivar groups accounted for 80% of the total isozyme variation.
Within-country variation accounted for 58% of the total variation while among-region and among-country variation within the
cultivar groups accounted for only 14% and 8% of the total variation. Analyses using log-linear models revealed that pronounced
non-random associations between and among alleles at many unlinked isozyme loci were organized in a non-hierarchical pattern,
and subspecific and macro-geographic differentiation was much more pronounced in multilocus phenotype frequencies than in
allelic frequencies at individual loci. These results suggest that selection on multilocus gene complexes was largely responsible
for the maintenance of the extensive isozyme variation within the species and the indica-japonica differentiation. Our results further suggest the independent domestication of indica and japonica, the dual origins of the indica rice from China and South Asia (India), and the differentiation of the ecotypes ’javanica’ and the ’temperate japonica’ within the japonica subspecies.
Received: 5 August 1999 / Accepted: 13 December 1999 相似文献
2.
Genotypic variability for callus formation and plant regeneration in rice (Oryza sativa L.) 总被引:3,自引:0,他引:3
T. Abe Y. Futsuhara 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1986,72(1):3-10
Summary Sixty rice varieties (Oryza sativa L.), belonging to three subspecies, japonica, indica and javanica (some japonicaXindica hybrids were included), were compared for their capacity for callus growth and plant regeneration. Tissue cultures initiated from mature seeds on Murashige and Skoog's (1962) medium with 2 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D) were transferred to a medium containing 0.02 mg/l 2,4-D and 10 mg/l kinetin, from which plantlets were regenerated. Large variabilities in callus growth and plant regeneration potentials were revealed among the varieties tested. Most japonica varieties formed a callus that weighed more than 100 mg per seed 30 days after inoculation, and showed a relatively high regenerative potential, whereas indica varieties, japonica-indica hybrids and javanica varieties showed poor callus growth and plant regeneration, although considerable varietal variation was observed in each subspecies. The callus growth potential was not correlated with the plant regeneration potential. Histological observations revealed that the epithelium cells of the scutellum mainly proliferated to form a callus, from which shoot and root primordia were differentiated independently from each other. The shoot primordia developed into plantlets when roots were formed adventitiously. In a few cases, shoots and roots were bilaterally initiated from a single primordium. 相似文献
3.
S. Vairavan E. A. Siddiq V. Arunachalam M. S. Swaminathan 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1973,43(5):213-221
Summary A representative group of 190 rice types collected from North-East India along with four standard varieties, three of which were indicas and one japonica, was studied to understand the nature of genetic divergence. Preliminary grouping was done by canonical analysis and the resultant 42 groups were further classified using the D2 statistic.The final grouping resulted in nine divergent clusters. The three indica standards were found in three different clusters indicating the wide available variability among them. The japonica standard formed a separate group by itself. A majority of the North-East Indian types formed clusters with indicas, whereas some were intermediate and still others were closer to japonica or indica, thus indicating a series of intergrades bridging indica and japonica.Height followed by leaf area was found to be important for primary and 100-grain weight, followed by amylose content for secondary differentiation. It appears that natural selection as well as human selection might have operated for characters differentiating rice types in Assam and North Eastern Himalayas. Geographical distance was not found to be related to genetic divergence. The study suggests that O. sativa contains innumerable but divergent forms, and its classification into definite varietal groups on an arbitrary basis such as isolation barrier, sexual affinity or geographic distribution would be far from reality. 相似文献
4.
H. Saruyama N. Shinbashi 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1992,84(7-8):947-951
Summary Proteins extracted from seed embryos of 29 different cultivated rice (Oryza sativa L.) and one wild rice (O. rufipogon Griff.) were compared by two-dimensional gel electrophoresis analysis. Among more than 300 protein spots on the gel we found some interesting variations in ten spots which were individually designated as proteins A-J. Protein E was observed in all indica cultivars but was not found in those of the subspecies japonica. In contrast, protein F was only detected in japonica cultivars. Protein A existed in all japonica cultivars but, with the exception of IR-36, could not be found in other indica cultivars. Therefore, proteins A, E and F can be used as markers for the identification of indica and japonica. Some so-called Javanica cultivars showed the characteristics of japonica subspecies with regard to proteins A and F, while one other cultivar of Javanica expressed a type intermediate between indica and japonica interms of proteins A and E. One feature discriminating between Javanica and japonica cultivars was found in the D, G, and J proteins which were expressed strongly in Javanica cultivars but were scarcely expressed in those of japonica. Expression of subspecies-specific proteins E and F in f1 hybrids was also investigated. 相似文献
5.
Analysis of indica- and japonica-specific markers of Oryza sativa and their applications 总被引:1,自引:0,他引:1
Xiao-Jun Dai Yuan-Zhu Yang Liang Zhou Li-Jun Ou Man-Zhong Liang Wen-Jia Li Gong-Ping Kang Liang-Bi Chen 《Plant Systematics and Evolution》2012,298(2):287-296
Asian rice, Oryza sativa L., is one of the most important crop species. Genetic analysis has established that rice consists of several genetically
differentiated variety groups, with two main groups, namely, O. sativa ssp. japonica kata and ssp. indica
kata. To determine the genetic diversity of indica and japonica rice, 45 rice varieties, including domesticated rice and Asia common wild rice (O. rufipogon Griff.), were analyzed using sequence-related amplified polymorphism, target region amplified polymorphism, simple sequence
repeat, and intersimple sequence repeat marker systems. A total of 90 indica- and japonica-specific bands between typical indica and japonica subspecies were identified, which greatly helped in determining whether domesticated rice is of the indica or japonica type, and in analyzing the consanguinity of hybrid rice with japonica, which were bred from indica and japonica crossed offspring. These specific bands were both located in the coding and non-encoding region, and usually connected with
quantitative trait loci. Utilizing the indica-japonica-specific markers, japonica consanguinity was detected in sterile hybrid rice lines. Many indica-japonica-specific bands were found in O. rufipogon. This result supports the multiple-origin model for domesticated rice. Javanica exhibited a greater number of indica-japonica-specific bands, which indicates that it is a subspecies of O. sativa L. 相似文献
6.
Summary Anthers from rice (Oryza sativa L.) subspecies japonica initiated more callus than their indica or indica x japonica counterparts. A mild stress, either by slow desiccation or heat shock, prior to the plating of anthers enhanced the ability to initiate callus. Slow dessication of anthers enhanced the ability of the japonica anthers to initiate callus even in medium that was supplemented with NaCl. The ability to initiate callus by the anthers plated on NaCl-supplemented medium decreased as the NaCl level in the medium increased. Among the regenerated plants 2.5% were albino and another 2% were haploid. Androclonal variation for tiller numbers, shoot height, plant dry matter and flowering were noticed in the progenies of the regenerated plants.Abbreviations NAA
-napthaleneacetic acid
- KT
Kinetin
- 2,4-D
2, 4-dichlorophenoxyacetic acid
- IAA
Indole-3-acetic acid
- BAP
N6 benzylaminopurine
- NFM
NaCl-free medium 相似文献
7.
8.
Asian cultivated rice(Oryza sativa L.),an important cereal crop worldwide,was domesticated from its wild ancestor 8000 years ago.During its long-term cultivation and evolution under diverse agroecological conditions, Asian cultivated rice has differentiated into indica and japonica subspecies.An effective method is required to identify rice germplasm for its indica and japonica features,which is essential in rice genetic improvements.We developed a protocol that combined DNA extraction from a single rice seed and the insertion/deletion(InDel) molecular fingerprint to determine the indica and japonica features of rice germplasm.We analyzed a set of rice germplasm,including 166 Asian rice varieties,two African rice varieties,30 accessions of wild rice species,and 42 weedy rice accessions,using the single-seeded InDel fingerprints(SSIF).The results show that the SSIF method can efficiently determine the indica and japonica features of the rice germplasm.Further analyses revealed significant indica and japonica differentiation in most Asian rice varieties and weedy rice accessions.In contrast,African rice varieties and nearly all the wild rice accessions did not exhibit such differentiation.The pattern of cultivated and wild rice samples illustrated by the SSIF supports our previous hypothesis that indica and japonica differentiation occurred after rice domestication under different agroecological conditions.In addition,the divergent pattern of rice cultivars and weedy rice accessions suggests the possibility of an endoferal origin(from crop)of the weedy rice included in the present study. 相似文献
9.
Microsatellites are useful tools to study the extent of divergence between two taxonomic groups that show high sequence similarity.
We have compared microsatellite distribution to illustrate genetic variation between the two rice genomes, Oryza sativa L. ssp. indica and Oryza sativa L. ssp. japonica. Microsatellite distribution proved to be non random as certain regions of very high microsatellite density have been identified.
Microsatellite density in the subspecies japonica was computed marginally higher than in the subspecies indica in the genomic regions compared between the two subspecies. Unexpectedly high microsatellite densities were observed in 5′-untranslated
regions of genes. These regions also displayed a clear motif bias. Some of the longest microsatellite repeats were found in
intron sequences. Frequency, as well as motif bias was also noted with respect to the association of microsatellites with
transposable elements. Microsatellite mutability values were exemplarily estimated for 90 loci by aligning the microsatellite
containing regions between the two genomes. Poor rates of finding an orthologue corresponded with high microsatellite mutability
in rice. These insights are likely to play a significant role in selecting microsatellite loci to be used in molecular breeding
and studying evolutionary dynamics of the two subspecies. 相似文献
10.
Kabin?Xie Jianwei?Zhang Yong?Xiang Qi?Feng Bin?Han Zhaohui?Chu Shiping?Wang Qifa?Zhang Lizhong?Xiong
We reported the isolation and identification of 10828 putative full-length cDNAs (FL-cDNA) from an indica rice cultivar, Minghui 63, with the long-term goal to isolate all full-length cDNAs from indica genome. Comparison with the databases showed that 780 of them are new rice cDNAs with no match in japonica cDNA database. Totally, 9078 of the FL-cDNAs contained predicted ORFs matching with japonica FL-cDNAs and 6543 could find homologous proteins with complete ORFs. 53% of the matched FL-cDNAs isolated in this study had
longer 5′UTR than japonica FL-cDNAs. In silico mapping showed that 9776 (90.28%) of the FL-cDNAs had matched genomic sequences in the japonica genome and 10046 (92.78%) had matched genomic sequences in the indica genome. The average nucleotide sequence identity between the two subspecies is 99.2%. A majority of FL-cDNAs (90%) could
be classified with GO (gene ontology) terms based on homology proteins. More than 60% of the new cDNAs isolated in this study
had no homology to the known proteins. This set of FL-cDNAs should be useful for functional genomics and proteomics studies. 相似文献
11.
Recombinational and mutational analyses were performed in an attempt to elucidate the nature of the genic differences and the ancestral relationship between the indica and japonica subspecies of Oryza sativa L. by taking representative varieties from each group. The absence of cytological aberrations at meiosis in indica×japonica hybrids suggest that genetic differences are predominantly genic rather than chromosomal. The pattern of variation induced in the key characters, and the frequency and spectra of mutations obtained in each group, failed to support the hypothesis that indica has given rise to japonica, and suggested that the two subspecies have originated from a common ancestor. 相似文献
12.
Genetic diversity and differentiation of indica and japonica rice detected by RFLP analysis 总被引:4,自引:0,他引:4
Qifa Zhang M. A. Saghai Maroof T. Y. Lu B. Z. Shen 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1992,83(4):495-499
Summary Genetic diversity and differentiation in indica and japonica groups of the cultivated rice (Oryza sativa L.) were studied by assaying DNA restriction fragment length polymorphisms of 12 indica and 14 japonica rice lines digested with three restriction endonucleases. A total of 49 probes were selected to represent the entire RFLP map at intervals of 20–30 cM. It was shown that 95 of the 145 possible probe/enzyme combinations, involving 43 probes and all three enzymes, detected restriction fragment length variation, and the degree of polymorphism varied greatly from one probe/enzyme combination to another. These results demonstrate that indica rice is genetically more diverse than japonica type. Significant differentiation between the two rice groups was detected by 33 probes representing 11 of the 12 rice chromosomes. It was deduced that the processes leading to differentiation involved a combination of molecular events that include base substitutions and insertion/deletions. 相似文献
13.
Quantification of total genomic DNA and selected repetitive sequences reveals concurrent changes in different DNA families in indica and japonica rice 总被引:11,自引:0,他引:11
Ohmido N Kijima K Akiyama Y de Jong JH Fukui K 《Molecular & general genetics : MGG》2000,263(3):388-394
This paper describes a fluorescence in situ hybridization (FISH) analysis of three different repetitive sequence families,
which were mapped to mitotic metaphase chromosomes and extended DNA fibers (EDFs) of the two subspecies of rice (Oryza sativa), indica and japonica (2n=2x=24). The repeat families studied were (1) the tandem repeat sequence A (TrsA), a functionally non-significant repeat; (2)
the [TTTAGGG]n telomere sequence, a non-transcribed, tandemly repeated but functionally significant repeat; and (3) the 5S ribosomal RNA
(5S rDNA). FISH of the TrsA repeat to metaphase chromosomes of indica and japonica cultivars revealed clear signals at the distal ends of twelve and four chromosomes, respectively. As shown in a previous
report, the 17S ribosomal RNA genes (17S rDNA) are located at the nucleolus organizers (NORs) on chromosomes 9 and 10 of the
indica cultivar. However, the japonica rice lacked the rDNA signals on chromosome 10. The size of the 5S rDNA repeat block, which was mapped on the chromosome 11
of both cultivars, was 1.22 times larger in the indica than in the japonica genome. The telomeric repeat arrays at the distal ends of all chromosome arms were on average three times longer in the indica genome than in the japonica genome. Flow cytometric measurements revealed that the nuclear DNA content of indica rice is 9.7% higher than that of japonica rice. Our data suggest that different repetitive sequence families contribute significantly to the variation in genome size
between indica and japonica rice, though to different extents. The increase or decrease in the copy number of several repetitive sequences examined here
may indicate the existence of a directed change in genome size in rice. Possible reasons for this phenomenon of concurrent
evolution of various repeat families are discussed.
Received: 9 August 1999 / Accepted: 29 December 1999 相似文献
14.
S. Negrão M. M. Oliveira K. K. Jena D. Mackill 《Molecular breeding : new strategies in plant improvement》2008,22(2):159-168
The cultivated rice (Oryza sativa L.) has two subspecies, indica and japonica. The japonica rice germplasm has a narrower genetic diversity compared to the indica subspecies. Rice breeders aim to develop new varieties with a higher yield potential, with enhanced resistances to biotic
and abiotic stresses, and improved adaptation to environmental changes. In order to face some of these challenges, japonica rice germplasm will have to be diversified and new breeding strategies developed. Indica rice improvement could also profit from more “genepool mingling” for which japonica rice could play an important role. Interesting traits such as low-temperature tolerance, and wider climate adaptation could
be introgressed into the indica subspecies. In the past decade, huge developments in rice genomics have expanded our available knowledge on this crop and
it is now time to use these technologies for improving and accelerating rice breeding research. With the full sequence of
the rice genome, breeders may take advantage of new genes. Also new genes may be discovered from the genepool of wild relatives,
or landraces of the genus Oryza, and incorporated into elite japonica cultivars in a kind of “gene revolution” program. Expectedly, new technologies that are currently being optimized, aiming
for novel gene discovery or for tracking the regions under selection, will be suggested as new breeding approaches. This paper
revisits breeding strategies successfully employed in indica rice, and discusses their application in japonica rice improvement (e.g. ideotype breeding, wide hybridization and hybrid performance). 相似文献
15.
H. S. Suh Y. I. Sato H. Morishima 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,94(3-4):316-321
Weedy rice (Oryza sativa L.) is an important resource for breeding and for studying the evolution of rice. The present study was carried out to identify
the genetic basis of the weedy rices distributed in various countries of the world. One hundred and fifty two strains of weedy
rice collected from Bangladesh, Brazil, Bhutan, China, India, Japan, Korea, Nepal, Thailand and the USA were tested for variations
in six morpho-physiological characteristics and in 14 isozyme loci. Twenty six weedy strains selected from the above materials
were assayed for the Est-10 locus, six RAPD loci of the nuclear genome, and one chloroplast locus. From the results of multivariate analysis based on
the morpho-physiological characteristics and the isozymes, weedy rice strains were classified into indica and japonica types, and each type was further divided into forms resembling cultivated and wild rice. Thus, four groups designated as
I, II, III and IV were identified. Weedy strains of group I (indica-type similar to cultivars) were distributed mostly in temperate countries, group II (indica-type similar to wild rice) in tropical countries, group III (japonica-type similar to cultivars) in Bhutan and Korea, group IV ( japonica-type similar to wild rice) in China and Korea. In group I, classified as indica, several strains showed japonica-specific RAPD markers, while some others had japonica cytoplasm with indica-specific RAPD markers in a heterozygous state at several loci. One weedy strain belonging to group II showed a wild rice-specific
allele at the Est-10 locus. However, in groups III and IV, no variation was ound either for the markers on Est-10 or for the RAPD loci tested. Judging from this study, weedy rice of group I might have originated at least partly from gene
flow between indica and japonica, whereas that of group II most probably originated from gene flow between wild and cultivated indica rice. Weedy rice of group III is thought to have originated from old rice cultivars which had reverted to a weedy form, and
that of group IV from gene flow between japonica cultivars and wild rice having japonica backgrounds.
Received: 2 May 1996 / Accepted: 30 August 1996 相似文献
16.
Karyological and taxonomic studies of Dugesia japonica Ichikawa et Kawakatsu in the Far East 总被引:3,自引:2,他引:3
A review of previous studies on the taxonomy, karyology and chorology of a polymorphic species Dugesia japonica from the Far East is presented. Two subspecies are now known: D. j. japonica (n = 8, 2x = 16, 3x = 24) and D. j. ryukyuensis (n = 7, 2x = 14, 3x = 21). An attempt has also been made to determine the definition of the B-chromosome as LB and SB and the variation of the karyotypes of both subspecies is described. Every known karyotype of D. japonica is classified into six groups (see Table 2). D. japonica from many localities has a diploid karyotype (2x), a triploid karyotype (3x) and an orthoploidic mixoploid karyotype of 2x & 3x. The origin and the karyological significance of these karyotypes are discussed. 相似文献
17.
Genetic diversity and its relationship to hybrid performance and heterosis in rice as revealed by PCR-based markers 总被引:47,自引:0,他引:47
J. Xiao J. Li L. Yuan S. R. McCouch S. D. Tanksley 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,92(6):637-643
Ten elite inbred lines (four japonica, six indica), chosen from those widely used in the hybrid rice breeding program at Human Hybrid Rice Research Center in China, were crossed to produce all possible hybrids excluding reciprocals. The 45 F1 hybrids along with the ten parents were evaluated for eight traits of agronomic importance, including yield potential, in a replicated field trial. The ten parents were analyzed with 100 arbitrary decamer oligonucleotide primers and 22 microsatellite (simple sequence repeats, SSRs) primer sets via polymerase chain reaction (PCR). Out of the 100 random primers used, 74 were informative and amplified 202 non-redundant bands (variants) with a mean of 2.73 bands per polymorphic primer. All 22 microsatellite primer sets representing 23 loci in the rice genome showed polymorphisms among the ten parents and revealed 90 alleles with an average of 3.91 per SSR locus. Cluster analysis based on Nei's genetic distance calculated from the 291 (202 RAPDs, 89 SSRs) non-redundant variants separated the ten parental lines into two major groups that corresponds to indica and japonica subspecies, which is consistent with the pedigree information. Strong heterosis was observed in hybrids for most of the traits examined. For the 43 diallel crosses (excluding 2 crosses not heading), yield potential, its components (including panicles per plant, spikelets per panicle and 1000-grain weight) and their heterosis in F1 hybrids showed a significant positive correlation with genetic distance. When separate analyses were performed for the three subsets, yield potential and its heterosis showed significant positive correlations with genetic distance for the 15 indica x indica crosses and the 6 japonica x japonica crosses; however, yield potential and its heterosis were not correlated with genetic distance for the 22 indica x japonica crosses. Results indicated that genetic distance measures based on RAPDs and SSRs may be useful for predicting yield potential and heterosis of intra-subspecific hybrids, but not inter-subspecies hybrids. 相似文献
18.
Three representative inter and intra‐subspecific crosses reveal the genetic architecture of reproductive isolation in rice
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Guangwei Li Xiaoting Li Yuan Wang Jiaming Mi Feng Xing Dahan Zhang Qiyan Dong Xianghua Li Jinghua Xiao Qifa Zhang Yidan Ouyang 《The Plant journal : for cell and molecular biology》2017,92(3):349-362
Systematic characterization of genetic and molecular mechanisms in the formation of hybrid sterility is of fundamental importance in understanding reproductive isolation and speciation. Using ultra‐high‐density genetic maps, 43 single‐locus quantitative trait loci (QTLs) and 223 digenic interactions for embryo‐sac, pollen, and spikelet fertility are depicted from three crosses between representative varieties of japonica and two varietal groups of indica, which provide an extensive archive for investigating the genetic basis of reproductive isolation in rice. Ten newly detected single‐locus QTLs for inter‐ and intra‐subspecific fertility are identified. Three loci for embryo‐sac fertility are detected in both Nip × ZS97 and Nip × MH63 crosses, whereas QTLs for pollen fertility are not in common between the two crosses thus leading to fertility variation. Five loci responsible for fertility and segregation distortion are observed in the ZS97 × MH63 cross. The importance of two‐locus interactions on fertility are quantified in the whole genome, which identify that three types of interaction contribute to fertility reduction in the hybrid. These results construct the genetic architecture with respect to various forms of reproductive barriers in rice, which have significant implications in utilization of inter‐subspecific heterosis along with improvement in the fertility of indica–indica hybrids at single‐ and multi‐locus level. 相似文献
19.
A chloroplast variation map generated using whole genome re‐sequencing of Korean landrace rice reveals phylogenetic relationships among Oryza sativa subspecies
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Wei Tong Qiang He Xiao‐Qiang Wang Min‐Young Yoon Won‐Hee Ra Fengpeng Li Jie Yu Win Htet Oo Sun‐Kyung Min Bu‐Woong Choi Eun‐Beom Heo Byoung‐Kook Yun Kyu‐Won Kim Tae‐Sung Kim Chang‐Yong Lee Yong‐Jin Park 《Biological journal of the Linnean Society. Linnean Society of London》2015,115(4):940-952
Although the overall structure of the chloroplast genome is generally conserved, several sequence variations have been identified that are valuable for plant population and evolutionary studies. Here, we constructed a chloroplast variation map of 30 landrace rice strains of Korean origin, using the Oryza rufipogon chloroplast genome (GenBank: NC_017835 ) as a reference. Differential distribution of single‐nucleotide polymorphisms and INDELs across the rice chloroplast genome is suggestive of a region‐specific variation. Population structure clustering revealed the existence of two clear subgroups (indica and japonica) and an admixture group (aus). Phylogenetic analysis of the 30 landrace rice strains and six rice chloroplast references suggested and supported independent evolution of O. sativa indica and japonica. Interestingly, two aus type accessions, which were thought to be indica type, shared a closer relationship with the japonica type. One hypothesis is that ‘Korean aus’ was intentionally introduced and may have obtained japonica chloroplasts during cultivation. We also calculated the nucleotide diversity of 30 accessions and compared the results to six rice chloroplast references. These data demonstrated that although nucleotide diversity is low in all strains tested, aus and indica have a higher nucleotide diversity than japonica. 相似文献
20.
Identification of quantitative trait loci controlling rice mature seed culturability using chromosomal segment substitution lines 总被引:1,自引:0,他引:1
Lina Zhao Hongju Zhou Liaoxun Lu Li Liu Xianghua Li Yongjun Lin Sibin Yu 《Plant cell reports》2009,28(2):247-256
The genetic transformation efficiency of a rice variety is largely determined by its tissue culturability. Establishment of
a highly efficient tissue-culture system has greatly accelerated the wide spread application of transgenic japonica varieties. However, such process for indica rice was hampered because this type of variety is recalcitrant to in vitro culture. This study aimed to map the quantitative
trait loci (QTLs) for mature seed culturability using a chromosomal segment substitution lines (CSSL) population derived from
a cross between an indica variety “Zhenshan 97B” and a japonica variety “Nipponbare”. The CSSLs consist of 139 lines each containing a single or a few introgression segments, and together
covering the whole “Nipponbare” genome. Every CSSL was tested by culturing on the two medium systems developed for the respective
indica and japonica parental varieties. The performance of culturability was evaluated by four indices: frequency of callus induction (CIF),
callus subculture capability (CSC), frequency of plant regeneration (PRF) and the mean plantlet number per regenerated callus
(MNR). All four traits displayed continuous variation among the CSSLs. With the culture system for japonica rice, three CIF QTLs, three CSC QTLs, three PRF QTLs and three MNR QTLs were detected. With the culture system for indica variety, six CIF QTLs, two CSC QTLs, three PRF QTLs and six MNR QTLs were identified, and these QTLs distributed on nine
rice chromosomes. Two QTLs of CIF and two QTLs of MNR were detected in both the japonica and indica rice culture system. The correlation coefficients of all the four traits varied depending on the culture systems. These results
provide the possibilities of enhancing the culturability of indica rice by marker-assisted breeding with those desirable alleles from the japonica.
Lina Zhao and Hongju Zhou have contributed equally to this work. 相似文献