| comparative rflp mapping of a wild rice, oryza officinalis, and cultivated rice, o. sativa. | a comparative rflp map was constructed in a wild rice, oryza officinalis, by using 139 genomic and cdna probes that had been used previously to map rflps in o. sativa. nine of the 12 chromosomes of o. officinalis were highly homosequential to those of o. sativa. a major rearrangement of gene order was detected in chromosome 1 and small inversions were found in chromosomes 3 and 11. fourteen translocated rflp markers were found, and chromosome 11 contained a high frequency of such translocated se ... | 1994 | 7913453 |
| characterization of new variants of a satellite dna from oryza officinalis, specific for the cc genome of wild rice. | two groups of tandemly repeated dna fragments have been isolated and cloned from the oryza officinalis genome (w 1278). these fragments have been sequenced and are 374 and 367 bp long. they were compared with an element previously isolated from another o. officinalis accession. they are 76 and 92% homologous to the latter and show 78% homology between themselves. the two types of elements are interspersed within large blocks of tandemly organized units. their copy number is in the range of 200,0 ... | 1993 | 7916734 |
| complex arrangement of dispersed repeated dna sequences in oryza officinalis. | a 525-bp bglii fragment was isolated from oryza officinalis dna (accession w1278) and shown to correspond to a new dispersed repetitive dna sequence with specificity restricted to a subset of the wild rice with a c genome. the sequence of the fragment was determined but it does not correspond to any sequence already present in databases. it contains several imperfect palindromes. larger genomic clones (12-18 kbp) were isolated and all contain sequences homologous to the bglii element. analysis o ... | 1996 | 8851805 |
| isolation of a new retrotransposon-like dna sequence and its use in analysis of diversity within the oryza officinalis complex. | to better understand the genetic diversity of the wild relatives of rice (oryza sativa l.) in the o. officinalis species complex repetitive dna markers were obtained from the diploid species of this complex. one cloned sequence from o. eichingeri gave intense hybridization signals with all species of the o. officinalis complex. this 242 bp clone, named poe.49, has a copy number from 0.9 to 4.0 x 10(4) in diploid species of this complex. analysis of the primary structure and database searches rev ... | 2000 | 11138942 |
| preferential occurrence of diazotrophic endophytes, azoarcus spp., in wild rice species and land races of oryza sativa in comparison with modern races. | several diazotrophic species of azoarcus spp. occur as endophytes in the pioneer plant kallar grass. the purpose of this study was to screen asian wild rice and cultivated oryza sativa varieties for natural association with these endophytes. populations of culturable diazotrophs in surface-sterilized roots were characterized by 16s rdna sequence analysis, and azoarcus species were identified by genomic fingerprints. a. indigens and azoarcus sp. group c were detected only rarely, whereas azoarcus ... | 2000 | 11220300 |
| diversity in the integrase coding domain of a gypsy-like retrotransposon among wild relatives of rice in the oryza officinalis complex. | the oryza officinalis complex is a genetically diverse, tertiary genepool of rice. we analyzed part of the primary structure of the integrase coding domain (icd) of a gypsy-like retrotransposon from species of the o. officinalis species complex. pcr was performed with degenerate primers that hybridized to conserved sequences in the integrase genes of gypsy-type retrotransposons, using total dna from different species of the o. officinalis complex as templates. cloning and sequencing of the pcr p ... | 2000 | 11519874 |
| endophytic colonization and in planta nitrogen fixation by a herbaspirillum sp. isolated from wild rice species. | nitrogen-fixing bacteria were isolated from the stems of wild and cultivated rice on a modified rennie medium. based on 16s ribosomal dna (rdna) sequences, the diazotrophic isolates were phylogenetically close to four genera: herbaspirillum, ideonella, enterobacter, and azospirillum. phenotypic properties and signature sequences of 16s rdna indicated that three isolates (b65, b501, and b512) belong to the herbaspirillum genus. to examine whether herbaspirillum sp. strain b501 isolated from wild ... | 2001 | 11679357 |
| high levels of genetic differentiation of oryza officinalis wall. ex watt. from china. | in order to determine the population genetic structure of wild rice (oryza officinalis wall. ex watt.), an endangered tropical and subtropical species, allozyme diversity encoded by 24 loci was analyzed electrophoretically in 145 individuals of eight natural populations from hainan, guangxi, and yunnan provinces, china. a fairly high genetic differentiation (f(st) = 0.882 and mean i = 0.786) was found among the studied populations. our results suggest that restricted gene flow may play a signifi ... | 2001 | 11948221 |
| rapd markers linked to brown planthopper nilaparvatha lugens resistance locus in rice. | brown plant hopper, a major pest in rice causes "hopper burn" in the field. the resistance gene for brown planthopper was mapped by using 20 recombinant inbred lines (ril's) derived from a cross between resistant line oryza. officinalis derivative (ir 54742-2-21-12-17-6) and a susceptible rice cultivar asd 16 using bulked segregant analysis. on an average of 4 loci were amplified and two rapd primers amplified loci that co-segregated with resistance/susceptibility. the segregating rapd loci were ... | 2000 | 12561959 |
| a genome-specific repetitive dna sequence from oryza eichingeri: characterization, localization, and introgression to o. sativa. | in the course of transferring the brown planthopper resistance from a diploid, cc-genome wild rice species, oryza eichingeri (irgc acc. 105159 and 105163), to the cultivated rice variety 02428, we have isolated many alien addition and introgression lines. the o. eichingeri chromatin in some of these lines has previously been identified using genomic in situ hybridization and molecular-marker analysis. here we cloned a tandemly repetitive dna sequence from o. eichingeri irgc acc105163, and detect ... | 2002 | 12582684 |
| construction of a genomic library of wild rice and agrobacterium-mediated transformation of large insert dna linked to bph resistance locus. | here we report the first genomic library of wild rice constructed on a plant-transformation-competent binary vector (bibac2) and transformation of the large insert dna into rice via agrobacterium. we selected oryza officinalis for genomic library construction. the library consists of 55,296 clones and stored in one hundred forty-four 384-well plates. random sampling of 140 clones indicated an average insert size of 71 kb at a range of 15-235 kb and 4.8% empty vectors. four wheat chloroplast prob ... | 2003 | 14636998 |
| a new chromosome fluorescence banding technique combining dapi staining with image analysis in plants. | in this study, a new chromosome fluorescence banding technique was developed in plants. the technique combined 4',6-diamidino-2-phenylindole (dapi) staining with software analysis including three-dimensional imaging after deconvolution. clear multiple and adjacent dapi bands like g-bands were obtained by this technique in the tested species including hordeum vulgare l., oryza officinalis, wall & watt, triticum aestivum l., lilium brownii, brown, and vicia faba l. during mitotic metaphase, the nu ... | 2004 | 15197560 |
| [mapping of a new resistance gene to bacterial blight in rice line introgressed from oryza officinalis]. | rice line 'b5', which was derived from the wild rice oryza officinalis wall ex watt through introgression, has been proved to be high resistant to brown planthopper, whitebacked planthopper and bacterial blight (xanthomonas oryzae pv. oryzae). in this study, the resistance to bacterial blight of 187 recombinant inbred lines (rils) from a cross between ' b5' and 'minghui63' were evaluated and rflp markers linked to the resistance gene were identified by bulked segregant analysis. analysis of the ... | 2004 | 15473325 |
| production and characterization of a complete set of individual chromosome additions from oryza officinalis to oryza sativa using rflp and gish analyses. | monosomic alien addition lines (maals) are valuable materials for comparative analyses of two distinct genomes, for elucidating introgression mechanisms, and for dissecting genes controlling complex traits. in the study reported here, maals of rice containing the complete genome of oryza sativa and individual chromosomes of oryza officinalis were produced. interspecific hybridizations were made between o. sativa l. ssp. japonica (cv, hejiang 19, 2 n = 24, aa) and o. officinalis (acc. hy018, 2 n ... | 2005 | 16177899 |
| microsatellite variation within and among populations of oryza officinalis (poaceae), an endangered wild rice from china. | oryza officinalis wall. ex watt. is an agriculturally important but seriously endangered species of wild rice. to obtain more accurate estimates of population structure for improved conservation planning of the species, genetic variability at 14 microsatellite dna loci was examined in population samples covering most of the species' range in china. considerable genetic variability (overall na = 1.886, p = 62%, ho = 0.056, he = 0.216, and hs = 0.277) was detected at the 14 loci in 442 individuals ... | 2005 | 16313593 |
| expression of the nifh gene of a herbaspirillum endophyte in wild rice species: daily rhythm during the light-dark cycle. | the expression of nitrogenase genes of herbaspirillum sp. b501 associated in shoot (leaf and stem) of wild rice, oryza officinalis, was studied by means of reverse transcription-pcr (rt-pcr) targeted at the nifh gene. rt-pcr analyses indicate that nifh transcript was detected exclusively from nitrogen-fixing cells of gfp-tagged strain b501gfp1 in both free-living and endophytic states by using a constitutive gfp gene transcript as a positive control. transcription of nifh and nitrogen fixation i ... | 2005 | 16332801 |
| diversity of centromeric repeats in two closely related wild rice species, oryza officinalis and oryza rhizomatis. | oryza officinalis (cc, 2n = 24) and oryza rhizomatis (cc, 2n = 24) belong to the oryza genus, which contains more than 20 identified wild rice species. although much has been known about the molecular composition and organization of centromeres in oryza sativa, relatively little is known of its wild relatives. in the present study, we isolated and characterized a 126-bp centromeric satellite (cento-c) from three bacterial artificial chromosomes of o. officinalis. in addition to cento-c, low abun ... | 2006 | 16463049 |
| cpd staining: an effective technique for detection of nors and other gc-rich chromosomal regions in plants. | mitotic chromosome spreads of 16 plant species belonging to six families were analyzed using an improved combined pi and dapi (cpd) staining procedure. fluorescence in situ hybridization (fish) with 45s rdna probe was conducted sequentially on the same spreads to evaluate the efficiency and sensitivity of the technique. fluorochrome staining with chromomycin a3 (cma)-dapi also was conducted to clarify the properties of the sequences involved in the cpd banded regions. our results revealed that a ... | 2006 | 16760123 |
| integration of hybridization-based markers (overgos) into physical maps for comparative and evolutionary explorations in the genus oryza and in sorghum. | with the completion of the genome sequence for rice (oryza sativa l.), the focus of rice genomics research has shifted to the comparison of the rice genome with genomes of other species for gene cloning, breeding, and evolutionary studies. the genus oryza includes 23 species that shared a common ancestor 8-10 million years ago making this an ideal model for investigations into the processes underlying domestication, as many of the oryza species are still undergoing domestication. this study inte ... | 2006 | 16895597 |
| molecular and cytogenetic characterization of an oryza officinalis-o. sativa chromosome 4 addition line and its progenies. | the wild species oryza officinalis wall. ex watt (2n = 24, cc) is a valuable genetic resource for rice (o. sativa l., 2n = 24, aa) breeding and genomics research. genomic in situ hybridization (gish) and molecular approaches were used to determine the nature and composition of the additional chromosome in a monosomic alien addition line (maal) of o. officinalis and its backcross progenies. the extra wild species chromosome in the maal (2n = 2x = 25) was a mosaic one, comprising of the long arm o ... | 2006 | 16941211 |
| multilocus analysis of nucleotide variation and speciation in oryza officinalis and its close relatives. | nucleotide variation in 10 unlinked nuclear genes was investigated in species-wide samples of oryza officinalis and its close relatives (oryza eichingeri and oryza rhizomatis). average estimates of nucleotide diversity were the lowest in o. rhizomatis ((sil) = 0.0038) and the highest in o. eichingeri ((sil) = 0.0057) that is disjunctly distributed in africa and sri lanka. these wild rice species appeared to harbor relatively low levels of nucleotide variation relative to other plant species beca ... | 2007 | 17182895 |
| [isolation and characterization of the centromeric bac clones from different genomes in genus oryza]. | centromeres play an important role in ensuring the correct segregation and transmission of chromosome during mitosis and meiosis in eukaryotes. in this research, we constructed five bac libraries for diploid wild rice with different genomes. together with the technique of colony blot hybridization and fluorescence in situ hybridization (fish), centromere-related bac clones were screened and characterized from different genomes. meanwhile, co-hybridization was detected between these clones and th ... | 2007 | 17646152 |
| simple sequence repeat analyses of interspecific hybrids and maals of oryza officinalis and oryza sativa. | wild rice is a valuable resource for the genetic improvement of cultivated rice (oryza sativa l., aa genome). molecular markers are important tools for monitoring gene introgression from wild rice into cultivated rice. in this study, simple sequence repeat (ssr) markers were used to analyze interspecific hybrids of o. sativa-o. officinalis (cc genome), the backcrossing progenies and the parent plants. results showed that most of the ssr primers (335 out of 396, 84.6%) developed in cultivated ric ... | 2008 | 17978880 |
| polyploid evolution in oryza officinalis complex of the genus oryza. | polyploidization is a prominent process in plant evolution, whereas the mechanism and tempo-spatial process remained poorly understood. oryza officinalis complex, a polyploid complex in the genus oryza, could exemplify the issues not only for it covering a variety of ploidy levels, but also for the pantropical geographic pattern of its polyploids in asia, africa, australia and americas, in which a pivotal genome, the c-genome, witnessed all the polyploidization process. | 2009 | 19828030 |
| a genetic resource for early-morning flowering trait of wild rice oryza officinalis to mitigate high temperature-induced spikelet sterility at anthesis. | high temperatures over 32-36 degrees c at anthesis induce spikelet sterility in rice. the use of a germplasm with an early-morning flowering (emf) trait has been hypothesized as a way of avoiding this problem. in this study, the effect of the emf trait on avoiding high temperature-induced sterility at anthesis by flowering at a cooler temperature in the early morning was evaluated. | 2010 | 20566680 |
| simple and efficient method for isolating cdna fragments of lea3 genes with potential for wide application in the grasses (poaceae). | cdna fragments of lea3 genes with a high gc content (from 68 to 77%) were found in several poaceae, including sorghum vulgare, saccharum officinarum, oryza officinalis, oryza meyeriana, ampelocalamus calcareus, cynodon dactylon, and zizania latifoli. they were successfully isolated by means of optimal experimental parameters, which included dimethyl sulfoxide as additive and degenerate primers "agetkas" and "agkdktg", and their sequences were analyzed. compared to the method of isolating genes b ... | 2010 | 20623457 |
| life-table analysis of the performance of nilaparvata lugens (hemiptera: delphacidae) on two wild rice species. | life tables of the planthopper nilaparvata lugens (stål) (hemiptera: delphacidae) on two wild rice species, oryza officinalis wall, ex watt. and oryza rufipogon griff., and on 'taichung native 1' (o. sativa indica tn1) were studied at 27 degrees c in the laboratory. the raw data were analyzed based on the age-stage, two-sex life table to take both sexes and the variable developmental rate among individuals and between sexes into consideration. the intrinsic rate of increase (r), the finite rate ... | 2010 | 21061962 |
| polymorphisms and evolutionary history of retrotransposon insertions in rice promoters. | retrotransposons are ubiquitous in higher plant genomes. the presence or absence of retrotransposons in whole genome and high throughput genomic sequence (htgs) from cultivated and wild rice was investigated to understand the organization and evolution of retrotransposon insertions in promoter regions. approximately half of the oryza sativa subsp. japonica 'nipponbare' promoters with retrotransposons conserved in oryza sativa subsp. indica '93-11' and four wild rice species showed higher sequenc ... | 2011 | 21823826 |