| oryzacystatins as the first well-defined cystatins of plant origin and their target proteinases in rice seeds. | two cystatins occur in mature seeds of the rice, oryza sativa l. japonica, which are named oryzacystatin i (oc-i) and oryzacystatin ii (oc-ii). these are highly homologous to each other and are significantly homologous to cystatin superfamily members of animal origin, especially to family-2 cystatins. however, both lack disulfide bonds as in the case of family-1 cystatins (stefins). each of oc-i and oc-ii thus seems to be chimerical of family-1 and family-2 cystatins, and we propose that a new c ... | 1991 | 1801735 |
| purification and partial characterization of pyruvate decarboxylase from oryza sativa l. | pyruvate decarboxylase(pyrdc) was purified from rice bran to a specific activity of 1 mu kat/mg and partially characterized. the holoenzyme is a tetramer of two types of subunits with molecular masses 64 kda and 62 kda. purified rice pyrdc exhibits positive cooperative kinetics with respect to pyruvate and functions with a significant lag phase. when compared to other plant pyrdc, the lag phase was shorter at low pyruvate concentrations and the s0.5 was smaller. the optimum ph (6.25) was also le ... | 1990 | 2269301 |
| introgression of genes from oryza officinalis well ex watt to cultivated rice, o. sativa l. | sterile ac hybrids between cultivated oryza sativa (aa) and a distant wild species, o. officinalis (cc), were backcross to o. sativa. most of the bc1 progenies were allotriploid (aac), a few were hypotriploid. aac progenies were again backcrossed to o. sativa. bc2 progenies consisting of disomic or aneuploid individuals were examined for the presence of o. officinalis traits. eleven different traits from o. officinalis were identified in these progenies. segregation data in the subsequent genera ... | 1990 | 24221103 |
| sucrose synthase in rice plants : growth-associated changes in tissue specific distributions. | different parts of the rice (oryza sativa l.) plant at different growth stages were analyzed for sucrose synthase (ss) by enzyme activity assay and enzyme-linked immunosorbent assay directly on the extracts or on the eluates from a gel filtration column. on a dry matter basis, the amount of soluble protein and ss activity decreased significantly, but the amount of enzyme protein changed little in growing leaves. in the grain, the ss activity was the highest at the early ripening stage and decrea ... | 1990 | 16667853 |
| proteins and amino acids of some local varieties of rice seeds (oryza sativa l.). | proteins and amino acids in four local rice (oryza sativa l.) varieties were identified. albumin and globulin were extracted from rice seeds, and the major promoters of these proteins were investigated by polyacrylamide gel electrophoresis to show their patterns. amino acid composition of the rice seed were determined quantitatively and qualitatively, and classified according to their acidic, basic and uncharged polar groups. essential amino acids for each variety were determined, and the hydrop ... | 1990 | 2247436 |
| fertile indica rice plants regenerated from protoplasts isolated from microspore derived cell suspensions. | rice plants (oryza sativa l., chinsurah boro ii var. indica) were regenerated from protoplasts isolated from microspore derived cell suspensions. a simple procedure for the establishment of such cell suspension cultures from embryogenic microcallus derived from cultured isolated microspores of indica-type rice is described. regenerating protoplasts could readily be isolated from 5-12 months old cell suspensions showing visible colony formation in the range of 180-1050 colonies/10(6) protoplasts ... | 1990 | 24226820 |
| mechanism of methane transport from the rhizosphere to the atmosphere through rice plants. | to clarify the mechanisms of methane transport from the rhizosphere into the atmosphere through rice plants (oryza sativa l.), the methane emission rate was measured from a shoot whose roots had been kept in a culture solution with a high methane concentration or exposed to methane gas in the gas phase by using a cylindrical chamber. no clear correlation was observed between change in the transpiration rate and that in the methane emission rate. methane was mostly released from the culm, which i ... | 1990 | 16667719 |
| efficient plant regeneration from rice protoplasts in general medium. | we established an efficient and reproducible procedure for protoplast propagation and fertile plant regeneration of rice (oryza sativa l.) cultivars nipponbare and taipei 309. selection of scutellum-derived secondary calli, the use of general medium and nurse culture were all found to be critical in the procedure. when 5 basal media (murashige and skoog, ry-2, modified r2, amino acid and general media) were compared, suspension callus growth rate, protoplast yield and plating efficiency were all ... | 1990 | 24226706 |
| nucleotide sequences of mitochondrial atpase subunit 9 genes from three lines of rice (oryza sativa l.) | | 1990 | 2143016 |
| the incidence and effects of hybridization between cultivated rice and its related weed red rice (oryza sativa l.). | the objectives of this study were (1) to determine if hybridization occurs naturally between cultivated rice and a closely related weed, red rice (both oryza sativa l.) and (2) to determine the incidence of hybridization and possible convergence of red rice with cultivated rice. both morphological and electrophoretic characters were used to confirm the existence of hybrids. a total of 12,000 seeds were collected from red rice plants from fields of six different rice cultivars and sown in a commo ... | 1990 | 28569027 |
| co-transformation of indica rice protoplasts with gusa and neo genes. | protoplasts of the indica rice (oryza sativa l.) variety, ir54, were transiently transformed with the gusa gene and stably transformed with both the neo and gusa genes. we show that peg-mediated co-transformation of protoplasts with two genes on separate plasmids coupled with selection on kanamycin is an effective way of transferring foreign gene(s) into the indica rice genome. the efficiency of co-transformation was generally 20-30%, i.e. the frequency of kanamycin-resistant calli having both t ... | 1990 | 24226605 |
| mitochondrial dna variation in long-term tissue cultured rice lines. | the effects of long-term tissue culture on mitochondrial dnas were examined using rice (oryza sativa) cell suspension cultures. mitochondrial dnas were isolated from p. i. 353705 (an indica subspecies of rice similar to 'asam 5'), its anther-culture-derived line bl2 (an 8-year-old cell suspension culture), and five other cell lines (a1, a7, a11, a13, and a23), also derived from bl2 and independently selected for resistance to the lysine analog, s-(2-amino)-ethyl-l-cysteine. mitochondrial dnas of ... | 1990 | 24220814 |
| a polyethylene glycol-mediated protoplast transformation system for production of fertile transgenic rice plants. | we have established an efficient procedure for protoplast transformation and regeneration of fertile transgenic plants of rice (oryza sativa l.) cultivars nipponbare and taipei 309. protoplasts were mixed with a plant-expressible hygromycin resistance gene and treated with 25% (w/v) polyethylene glycol. stringent selection of transformed colonies was applied to 14-day-old regenerated protoplasts in the presence of 95 micromolar of hygromycin b for 12 days. after selection, 450 and 200 resistant ... | 1990 | 16667593 |
| mechanism for the activation of plasma membrane h-atpase from rice (oryza sativa l.) culture cells by molecular species of a phospholipid. | the activation of h(+)-atpase solubilized from plasma membrane of rice (oryza sativa l. var nipponbare) culture cells was examined by the exogenous addition of various phospholipids, free fatty acids, glycerides, polar head groups of phospholipids and molecular species of phosphatidylcholine (pc). h(+)-atpase activity appeared to be stimulated by phospholipids in the following order: asolectin > phosphatidylserine > pc > lysophosphatidylcholine > phosphatidylglycerol, and maximal atpase activati ... | 1990 | 16667556 |
| induction of pyrophosphate:fructose 6-phosphate 1-phosphotransferase by anoxia in rice seedlings. | rice (oryza sativa) seeds were imbibed for 3 days and the seedlings were further incubated for 8 days in the presence of either air or nitrogen. in aerobiosis, the specific activity of pyrophosphate:fructose 6-phosphate 1-phosphotransferase and that of the atp-dependent phosphofructokinase increased about fourfold. in anaerobiosis, the specific activity of atp-dependent phosphofructokinase remained stable, whereas that of pyrophosphate:fructose 6-phosphate 1-phosphotransferase increased as much ... | 1990 | 16667507 |
| a repeated chromosomal dna sequence is amplified as a circular extrachromosomal molecule in rice (oryza sativa l.). | the plasmid pe10 is a pbr322-derived plasmid carrying a 4.5 kb rice (oryza sativa l.) repeated dna sequence. the cloned sequence has been shown to be amplified in cultured rice cells. the analysis of practically intact chromosomal rice dna molecules by pulsed field gel electrophoresis has now shown that the amplification is associated with the appearance of extrachromosomal molecules. in fact, pe10 hybridizes exclusively with unfractionated dna from leaf protoplasts, while it recognizes predomin ... | 1990 | 2233681 |
| screening of rice (oryza sativa l.) genotypes for physiological characters contributing to salinity resistance, and their relationship to overall performance. | phenotypic resistance of salinity is expressed as the ability to survive and grow in a salinised medium. some subjective measure of overall performance has normally been used in plant breeding programmes aimed at increasing salinity resistance, not only to evaluate progeny, but to select parents. salinity resistance has, at least implicitly, been treated as a single trait. physiological studies of rice suggest that a range of characteristics (such as low shoot sodium concentration, compartmentat ... | 1990 | 24226357 |
| double-stranded rna and male sterility in rice. | double-stranded rna (dsrna) was isolated from rice oryza sativa ssp. japonica, but not from other subspecies. the dsrna has been found in all of the examined cytoplasmic male-sterile (cms) lines of bt (chinsurah boro ii)-type rice, but was not detected in their companionate maintainer lines. it is uniquely and positivley correlated with the cms trait in bt-type rice. recently, the dsrna was also found in a nuclear malesterile (nms) rice, nongken 58s, but was not found in its normal nongken 58. t ... | 1990 | 24226462 |
| the alpha-amylase genes in oryza sativa: characterization of cdna clones and mrna expression during seed germination. | two cdna clones, pos103 and pos137, were isolated which code for distinct alpha-amylase isozymes in germinating rice seeds. sequence analysis indicated that the clones encode polypeptides of approximately 48 kda, both of which possess a signal peptide involved in directing secretion of the protein. comparison of the two rice alpha-amylase amino acid sequence showed that they are 76% similar to each other, while showing 85% to 90% similarity with other cereal alpha-amylases. a comparison of eleve ... | 1990 | 2370848 |
| genomic nucleotide sequence of four rice (oryza sativa) actin genes. | | 1990 | 2102841 |
| plant regeneration from protoplasts of a super chinese rice (oryza sativa l.) cultivar--zhonghua no.8. | green rice plants were regenerated from protoplasts, which were derived from cell suspension of oryza sativa l. cut. zhonghua no. 8, a super chinese rice cultivar with high productivity, good quality and high resistance to both bacterial blight and blast. the embryogenic calli were initiated from mature embroys. it took about 4 months to establish the cell suspenion. the regeneration plants from protoplasts were obtained in 2 months after the isolation of protoplasts. | 1990 | 2104199 |
| inheritance of two endosperm protein loci in rice (oryza sativa l.). | previous studies indicated two types of phenotypic protein markers as two minor bands of sds-page for rice storage protein. a variant derived from a pakistani variety, dular, was found to show a mobility variant with band 11, a relatively faster-moving band as compared to band 10, while most of the other cultivated rices exhibited band 10 at a molecular weight of around 100-110 k. band 11 was also observed in several wild rice species. how this variant occurred is not known. another marker is ch ... | 1989 | 24226007 |
| selection of higher regenerative callus and change in isozyme pattern in rice (oryza sativa l.). | calli were initiated from seedling roots in rice (oryza sativa l. var. tadukan) and subcultured at 45-day intervals on ms medium supplemented with 2 mg/l 2,4-d. sectors of callus which differentiated shoot meristems (green spots) under the same 2,4-d concentration were selected from the calli subcultured 90 days after initiation. the selection was continued for about 2 years. responses to 2,4-d between original and selected lines differed considerably, although differentiation was not generally ... | 1989 | 24225824 |
| effects of cold-treatment on protein synthesis and mrna levels in rice leaves. | the effects of cold on protein and rna metabolism in leaves of rice (oryza sativa l.) seedlings were investigated. treatment with a diurnal cycle of 15/10 degrees c or 11/6 degrees c for up to 1 week resulted in progressive changes in the protein synthesis pattern after in vivo labeling of intact rice leaves with [(35)s]methionine. these changes were reversed when the seedlings were returned to normal growth temperatures. while de novo accumulation of several abundant proteins was suppressed, so ... | 1989 | 16667159 |
| increased proteolysis of senescing rice leaves in the presence of nacl and kcl. | nacl and kcl enhanced the degradation of chlorophylls and proteins in detached rice (oryza sativa) leaves in a concentration-dependent manner. ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco) accounted for 73 to 80% of the protein lost by day 4 in the light. nacl at 50 millimolar increased proteolysis by 21% over the control in 4 days, but the addition of cycloheximide reduced the increase to about one-half. cycloheximide alone had no effect on proteolytic activity during this period. l ... | 1989 | 16667137 |
| polyamines in rice seedlings under oxygen-deficit stress. | incubation of 3-d-old seedlings of oryza sativa l. cv arborio under anaerobic conditions, leads to a large increase in the titer of free putrescine while aerobic incubation causes a slight decrease. after 2 days, the putrescine level is about 2.5 times greater without oxygen than in air. the rice coleoptile also accumulates a large amount of bound putrescine and, to a lesser extent, spermidine and spermine (mainly as acid-soluble conjugates). accumulation of conjugates in the roots is severely i ... | 1989 | 16667132 |
| three cdna sequences coding for glutamine synthetase polypeptides in oryza sativa l. | | 1989 | 2577497 |
| development of salt tolerant lines of kdml and lpt rice cultivars through tissue culture. | salt tolerant lines of indica rice (oryza sativa l.) were selected out of kdml and lpt cultivars. the first selection was made in vitro by incorporating 1 or 2% nacl in the culture media. embryogenic calli from mature embryo were subjected to a salt stress for four weeks. regeneration rates after salt stress were reduced to 0.076% or less as against regeneration rates of 8.3 to 30% normally obtained for non-stressed conditions. seedlings of regenerants and of following generations were treated w ... | 1989 | 24233365 |
| polyamines as modulators of salt tolerance in rice cultivars. | the effect of nacl on the endogenous levels of diamine, putrescine and polyamines, spermidine and spermine, was studied in the shoot system of salt-tolerant and salt-sensitive lines of rice (oryza sativa l.) cultivars during three growth stages. salt stress increased the levels of diamine and polyamine in varying degrees among nine rice cultivars investigated. salt tolerant au1, co43, and csc1 were effective in maintaining high concentrations of spermidine and spermine, while the content of putr ... | 1989 | 16667061 |
| heavy metal tolerance of rice plants (oryza sativa l.) to some metal oxides at the critical levels. | the toxicity of metal oxides (cdo, zno, pbo) were compared with each other and the critical levels of metal uptake by rice plants were determined. the order of metal toxicity to rice plants is cdo greater than zno greater than pbo. the highest concentration obtained for unpolished rice was 4.97 micrograms/g at the cd 10,000 ppm in soil. this values is higher than every other we have seen in the reports for treatment with cdo. we are able to find out that the concentration of 10,000 ppm cd in the ... | 1989 | 2600364 |
| membrane-associated binding sites for indoleacetic acid in the rice coleoptile. | as described previously, the sensitivity of rice (oryza sativa l.) coleoptiles to auxin is modulated by oxygen. under anoxia, coleoptile elongation is insensitive to exogenously applied indole-3-acetic acid (iaa), whereas its sensitivity increases in air in the presence of the exogenous stimulus. here we report the presence of two independent classes of membrane-bound iaa-binding sites in air-grown coleoptiles. their binding activity is strictly correlated with the system's sensitivity to iaa. w ... | 1989 | 24201521 |
| partial proteolysis of rice phytochrome: comparison with oat phytochrome. | phytochrome was isolated from etiolated rice seedlings (oryza sativa l.) by slight modification of the procedure for oat phytochrome. spectral data of rice phytochrome are comparable with those of oat and rye phytochrome. controlled proteolysis with endoproteinases lys-c and glu-c yielded defined fragments some of which were different for pr and pfr. the fragments were identified by comparison with the corresponding fragments of oat phytochrome and by comparison of the amino acid sequences of ri ... | 2015 | 2686670 |
| structure and expression of the rice glutelin multigene family. | a near full-length cdna and three genomic clones for rice (oryza sativa l.) glutelin were isolated and studied. based on nucleic acid sequence and southern blot analyses, the three isolated glutelin genomic clones were representative members of three gene subfamilies each containing five to eight copies. a comparison of dna sequences displayed by relevant regions of these genomic clones showed that two subfamilies, represented by clones gt1 and gt2, were closely related and evolved by more recen ... | 1989 | 2745459 |
| developmental mutants showing abnormal organ differentiation in rice embryos. | zygotes of rice (oryza sativa l. cv taichung 65) were treated with 1.0 mm solution of the chemical mutagen n-methyl-n-nitrosourea. out of 1420 m2 lines, 28 single-locus recessive mutants on embryogenesis were identified. among them, we analyzed 11 mutants in the present study, which differentiated the shoot (plumule) and/or root (radicle) with abnormality. of the 11 mutants, two showed no shoot differentiation with normal root. on the other hand, we could not detect any mutant which exhibited a ... | 1989 | 24227023 |
| plant regeneration from indica rice (oryza sativa l.) protoplasts. | rice (oryza sativa l.) plants of the indica cultivar ir54 were regenerated from protoplasts. conditions were developed for isolating and purifying protoplasts from suspension cultures with protoplast yields ranging from 1·10(6) to 15·10(6) viable protoplasts/1 g fresh weight. protoplast viability after purification was generally over 90%. protoplasts were cultured in a slightly modified kao medium in a petri plate by placing them onto a millipore filter positioned on top of a feeder (nurse) cult ... | 1989 | 24212899 |
| the nucleotide sequences and expression of genes for the beta and epsilon subunits of atp synthase from rice (oryza sativa l.) | the genes for the beta and epsilon subunits of atp synthase were cloned from rice chloroplast dna. the nucleotide sequences and the deduced amino acid sequences of these genes were determined. the site of initiation of transcription was examined by s1-mapping analysis. the relation between stability of mrna and that of a stem and loop structure at the 3' end of mrna is discussed. | 1989 | 2534354 |
| plant regeneration from cytoplasmic hybrids of rice (oryza sativa l.). | we obtained cybrid plants by electrofusing γ-irradiated protoplasts of a cytoplasmic male-sterile line "a-58 cms" (oryza sativa l.) and iodoacetamide (ioa)-treated protoplasts of the fertile (normal) rice cultivar "fujiminori". the cybridity of the plants was confirmed by mitochondrial (mt) dna restriction endonuclease, and plasmid-like dna analyses, and by isozyme, cytological and morphological investigations. the chromosome number of the cybrid plants is 24. | 1989 | 24232605 |
| sugar content and activity of sucrose metabolism enzymes in milled rice grain. | most rice (oryza sativa l.) cultivars grown in the united states were selected for endosperm starch properties and not soluble sugar content. the minor pool of soluble sugar may affect the qualities of rice as a food. some cultivar variation in soluble sugar content was detected in milled grain, essentially the starchy endosperm, of long grain varieties. milled grain of cultivars lemont and texmati had a soluble sugar content of 0.21 and 0.35% (w/w), respectively, on a fresh weight basis. the do ... | 1989 | 16666638 |
| seed dormancy in red rice : vii. structure-activity studies of germination stimulants. | many chemically dissimilar substances break dormancy of seeds, but the relationship between chemical structure and physiological activity is unknown. in this study, the concentrations of organic acids, esters, aldehydes, alcohols, and inorganic weak acids required to elicit 50% germination of initially dormant, dehulled red rice seeds (oryza sativa) were determined. the activity of most substances was very highly and inversely correlated to lipophilicity as measured by octanol/water partition co ... | 1989 | 16666635 |
| establishment of a system of high-frequency embryogenesis from long-term cell suspension cultures of rice (oryza sativa l.). | suspension cultures which maintained embryogenic potency for more than 18 months were established from excised immature embryos of rice (oryza sativa l. cv. konansou). the cultures were subcultured every three days in n6 medium supplemented with proline (10 mm), casein hydrolysate (300 mg/l), sucrose (30 g/l) and 2,4-d (1 mg/l). the frequency of embryogenesis from the embryogenetic suspension cultures reached about 90% when cell clusters (about 1 mm in diameter) were transferred to a solid mediu ... | 1989 | 24232530 |
| long-term effects of land application of aqueous oil effluent on photosynthetic efficiency of certain varieties of oryza sativa l. | | 1989 | 2920225 |
| mrnas and a cloned histone gene are differentially expressed during anther and pollen development in rice (oryza sativa l.). | spatial and temporal changes in the distribution of mrna sequences during anther and pollen development in rice (oryza sativa) were investigated by in situ hybridization with [3h]polyuridylic acid ([3h]poly(u)) and a cloned rice histone gene probe. annealing of sections with [3h]poly(u) showed that poly(a)-containing rna (poly(a)+rna) was uniformly distributed in the cells of the anther primordium. during the formation of the archesporial initial, the primary parietal cell, the primary sporogeno ... | 1989 | 2476454 |
| free proline contents in two different groups of rice mutants resistant to hydroxy-l-proline. | in four rice (oryza sativa l.) mutants resistant to hydroxy-l-proline (hyp), hyp101, hyp203, hyp205 and hyp210, and in their original variety, nipponbare, free proline and hyp contents in the seeds and in the 14-day-old seedlings have been determined. the four mutants can be divided into two groups: hyp101 and hyp203 are classified as to recessive gene and the levels of free proline are similar to that of the original variety; the second group includes mutants hyp205 and hyp210 where the hyp res ... | 1989 | 24232472 |
| the performance of three cultivars of rice grown near to, and distant from, a fertiliser plant. | the effects of three cultivars, two water regimes and two rates of applying nitrogen fertilisers were tested when studying the performance of rice (oryza sativa l.) near to, and distant from, a fertiliser plant emitting atmospherically dispersed pollutants. the atmosphere near the fertiliser plant had average daily peak concentrations of 144 and 210 microg m(-3) of so(2) and no(2), respectively. growth was less near to, than at a distance from, the fertiliser plant. on average it was decreased b ... | 1989 | 15092427 |
| [characterization of a cloned dna fragment of rice chloroplast and location rbcl gene in the recombinant plasmid]. | the pure rice (oryza sativa, subsp. indica, cv. zhenshan 97b) chloroplast dna was digested by restriction enzyme bamhi and the resulting fragments were ligated to the bamhi site of pbr322. one recombinant plasmid which contains a 19.3kb insertel dna fragment was isolated from the clone bank and was named posb1. a physical map of the recombinant plasmid was constructed by cleavage with ten restriction endonucleases, and the gene rbcl was located on the posb1. | 1989 | 2561754 |
| molecular mapping of rice chromosomes. | we report the construction of an rflp genetic map of rice (oryza sativa) chromosomes. the map is comprised of 135 loci corresponding to clones selected from a psti genomic library. this molecular map covers 1,389 cm of the rice genome and exceeds the current classical maps by more than 20%. the map was generated from f2 segregation data (50 individuals) from a cross between an indica and javanica rice cultivar. primary trisomics were used to assign linkage groups to each of the 12 rice chromosom ... | 1988 | 24232389 |
| distribution of mitochondrial plasmid-like dna in cultivated rice (oryza sativa l.) and its relationship with varietal groups. | mitochondrial (mt) plasmid-like dna was found in most of more than 100 rice cultivars (oryza sativa l.) by the use of 0.7% agarose gel electrophoresis (age). the dna varied in molecular weight and number. by electron microscopy, small circular dnas of different sizes could be detected in addition to the dnas of high molecular weight, even in cultivars in which mt plasmid-like dna was not detected by age. the detection of the mt plasmid-like dnas by age did not depend on their presence or absence ... | 1988 | 24232388 |
| sequence of the chloroplast psbf gene encoding the photosystem ii 10 kda phosphoprotein from oryza sativa l. | | 1988 | 3057446 |
| structure, expression, and heterogeneity of the rice seed prolamines. | by screening two rice (oryza sativa l.) seed cdna libraries, recombinant cdna clones encoding the rice prolamine seed storage protein were isolated. based on cross-hybridization and restriction enzyme map analyses, these clones can be divided into two homology classes. all clones contain a single open reading frame encoding a putative rice prolamine precursor (molecular weight = 17,200) possessing a typical 14-amino acid signal peptide. the deduced primary structures of both types of prolamine p ... | 1988 | 16666363 |
| production of kanamycin resistant rice tissues following dna uptake into protoplasts. | rice protoplasts (oryza sativa l. v taipei 309) have been transformed to kanamycin resistance following uptake of pcamvneo induced by electroporation, peg and peg combined with electroporation. protoplast-derived colonies selected on medium containing 100 μg/ml of kanamycin expressed nptii activity, and contained dna that hybridised to a 1.0 kb bamhi fragment of pcamvneo carrying the nptii gene. expression of the transformation frequency in relative terms (number of kanamycin resistant colonies ... | 1988 | 24240260 |
| molecular analysis of organelle dna of different subspecies of rice and the genomic stability of mtdna in tissue cultured cells of rice. | chloroplast (ct) and mitochondrial (mt) dnas were isolated from two subspecies of rice (oryza sativa), japonica (calrose 76) and indica (pi353705) and compared by restriction endonuclease fragment pattern analysis. similarly, pi353705 (a5) mtdna was also compared with the mtdna of its long term tissue cultured line, bl2. variation in the ctdna of the 2 subspecies was detected with two (avai and bgli) of the 11 restriction endonucleases tested, whereas their mtdnas showed considerable variation w ... | 1988 | 24232271 |
| the biophysical basis of elongation growth in internodes of deepwater rice. | partial submergence induces rapid internodal elongation in deepwater rice (oryza sativa l., cv habiganj aman ii). we measured in vivo extensibility, tissue tension, hydraulic conductance and osmotic potential in the region of cell elongation in the uppermost internode. the in vivo extensibility of the internode, measured by stretching of living tissue with a custom-made constant stress extensiometer, rose rapidly following submergence of the plant. both the elastic (e(el)) and plastic (e(pl)) ex ... | 1988 | 16666308 |
| factors influencing protoplast viability of suspension-cultured rice cells during isolation process. | callus cells of rice (oryza sativa l.) that were actively dividing in suspension culture had lost the ability to divide during the isolation process of protoplasts. factors influencing the protoplast viability were examined using highly purified preparations of cellulase c(1), xylanase, and pectin lyase, which were essential enzymes for the isolation of protoplasts from the rice cells. the treatment of the cells with xylanase and pectin lyase, both of which are macerating enzymes, caused cellula ... | 1988 | 16666273 |
| interaction of a gibberellin-induced factor with the upstream region of an alpha-amylase gene in rice aleurone tissue. | the interaction between the dna sequences of an alpha-amylase (ec 3.2.1.1) gene and a tissue-specific factor induced in rice (oryza sativa l.) aleurone tissue by gibberellin was studied. dna mobility-shift during electrophoresis indicated that a 500-base-pair sequence (hs500) of a rice alpha-amylase genomic clone (osamy-a) specifically interacted with a factor from gibberellin-induced rice aleurone tissue. the amount of complex formed between the hs500 dna fragment and the gibberellin-induced fa ... | 1988 | 3261867 |
| chromosomal location of genes conditioning low amylose content of endosperm starches in rice, oryza sativa l. | eight dull mutants that lower the amylose content of rice endosperm as well as waxy mutant and a cultivar with common grains were crossed in a diallele manner. the amylose content of f1 and f2 seeds was determined on the basis of single grain analysis. it was concluded that the low amylose content of dull mutants is under monogenic recessive control. alleles for low amylose content are located at five loci designated as du-1, du-2, du-3, du-4 and du-5. these loci are independent of wx locus loca ... | 1988 | 24232104 |
| differences between wheat and rice in the enzymic properties of ribulose-1,5-bisphosphate carboxylase/oxygenase and the relationship to photosynthetic gas exchange. | the kinetic parameters of ribulose-1,5-bisphosphate (rubp) carboxylase/oxygenase (ec 4.1.1.39) in wheat (triticum aestivum l.) and rice (oryza sativa l.) were determined by rapidly assaying the leaf extracts. the respective k m and v max values for carboxylase and oxygenase activities were significantly higher for wheat than for rice. in particular, the differences in the v max values between the two species were greater. when the net activity of co2 exchange was calculated at the physiological ... | 1988 | 24221414 |
| interaction of asparagine-linked oligosaccharides with an immobilized rice (oryza sativa) lectin column. | the carbohydrate-binding specificity of rice (oryza sativa) lectin was investigated by testing the ability of radioactively labelled glycopeptides and oligosaccharides to bind to a rice lectin-sepharose 4b column. rice lectin binds asparagine-linked oligosaccharides through the core nn'-diacetylchitobiose moiety. whereas beta 1-4-mannose enhances the binding strength only to a small extent, alpha 1-3-linked core mannose increases it considerably. a core alpha 1-6-linked mannose residue has a sli ... | 1988 | 3355507 |
| isolation and hypoglycemic activity of oryzabrans a, b, c and d, glycans of oryza sativa bran. | | 1988 | 3375329 |
| effect of gamma-irradiated sludge on the growth and yield of rice (oryza sativa l. var. gr-3). | the effects of gamma-irradiated sludge on the growth and yield of rice (oryza sativa l. var. gr-3) in pot cultures have been studied. compared to plants grown only in soil, shoot length, root length, fresh weight, dry weight, total proteins, total soluble sugars, starch and chlorophyll content of plants grown in soil supplemented with unirradiated or gamma-irradiated sludge were found to be significantly increased. irradiation of sludge significantly stimulated the linear growth of shoot and roo ... | 1988 | 15092639 |
| carbon isotope ratios demonstrate carbon flux from c(4) host to c(3) parasite. | carbon isotope ratios of mature leaves from the c(3) angiosperm root hemiparasites striga hermonthica (del.) benth (-26.7 per thousand) and s. asiatica (l.) kuntze (-25.6 per thousand) were more negative than their c(4) host, sorghum (sorghum bicolor [l.] moench cv csh1), (-13.5 per thousand). however, in young photosynthetically incompetent plants of s. hermonthica this difference was reduced to less than 1 per thousand. differences between the carbon isotope ratios of two c(3)-c(3) association ... | 1987 | 16665818 |
| genetic and biochemical basis of scent in rice (oryza sativa l.). | the inheritance and biochemical basis of scent in rice was studied in the f2 population along with the f1 and its two parents, scented and non-scented 'pokura' rice strains. the f1 plants were found to be nonscented while the f2 plants seggregated into a 3∶1 ratio (non-scented: scented). in scented f2 seggregants and in the scented parental strain, a fast moving esterase isozyme, rf 0.9, is missing whereas it is present in all nonscented f2 seggregants, f1s, and in the non-scented parent. this s ... | 1987 | 24241193 |
| field performance and cytology of protoplast-derived rice (oryza sativa): high yield and low degree of variation of four japonica cultivars. | protoplast-derived rice plants of four japanese cultivars, nipponbare, fujisaka 5, norin 14 and iwaimochi were individually cultivated in a submerged paddy field. they exhibited more stems, which resulted in more panicles than respective control plants. other characteristics of protoplast-derived plants were (compared with controls): a slightly shorter or similar culm length, fewer spikelets per panicle, slightly lower seed fertility and similar or lighter 1,000 kernel weight. grain yield of pro ... | 1987 | 24240226 |
| amylase activity and growth in internodes of deepwater rice. | isoelectrofocusing, product analysis, thermal denaturation studies and affinity chromatography on cycloheptaamylose-sephadex were used to identify the amylolytic enzymes in internodes of deepwater rice (oryza sativa l.). amylolytic activity in internodes of deepwater rice consists of α-amylase (sometimes separated into two isoforms) and of β-amylase. during submergence of whole plants, α-amylase activity increases in young, growing internodes, but β-amylase activity declines. although non-growin ... | 1987 | 24225795 |
| position of anthers at plating and its influence on anther callusing in rice. | effect of position of anthers at plating in relation to their ability to form callus was studied in rice (oryza sativa var. taipei 309). among the callusing anthers, about 60% were those positioned on edge with one lobe in contact with the medium while the rest were flat with both lobes touching the medium. anthers in both positions produced calli and regenerated green plants. | 1987 | 24248769 |
| seed dormancy in red rice : vi. monocarboxylic acids: a new class of ph-dependent germination stimulants. | the weak acid character of many previously identified, but otherwise chemically dissimilar, dormancy-breaking compounds may contribute to their physiological activity. to test this idea, short chain monocarboxylic acids of one to six carbons, for which no previous reports of such activity exist, were incubated with dormant, dehulled red rice (oryza sativa) seeds. greater than 90% germination was observed after 24 hours of imbibition with 19 millimolar formic, 53 millimolar acetic, 20 millimolar ... | 1987 | 16665509 |
| in vitro segregation of marker genes in anther cultures of rice. | segregation of genes controlling expression of anthocyanin pigmentation in rice (oryza sativa l. subsp. indica) leaf blade and leaf sheath was examined in the microspore-derived plants. the segregation pattern of marker genes was found to fit closely the expected gametic segregation ratios among microspore-derived green as well as albino plants. microspore-derived in vitro regenerated plants expressed genetic traits similar to seedlings. the results indicate that the germ cell culture technique ... | 1987 | 3610948 |
| differentiation of rice varieties by electrophoresis of embryo protein. | variations in the embryo proteins separated by sds-page have been observed in 43 cultivated varieties of oryza sativa l. cluster and discriminant analysis applied to both protein components and morphological characters indicate that knowledge of the differences in embryo proteins can improve our understanding of genetic affinity and make it easier to differentiate between varieties of similar genetic backgrounds. | 1987 | 24241569 |
| fatty acids of rice coleoptiles in air and anoxia. | the metabolism of lipids, like that of other components, was adversely and strongly affected when rice (oryza sativa l.) coleoptiles were grown anaerobically. in aerobic coleoptiles, the amounts of total fatty acid, phospholipid, and total lipid per coleoptile increased by 2.5- to 3-fold between days three and seven, whereas under anoxia, the increases were all less than 60%. the total amount of lipid at day seven in anoxia was less than 30% of that in air. in air, the total fatty acid content a ... | 1987 | 16665478 |
| an evaluation of 2,5-norbornadiene as a reversible inhibitor of ethylene action in deepwater rice. | partial submergence of deepwater rice (oryza sativa l. cv habiganj aman ii) elicits three responses: enhancement of internodal elongation, inhibition of leaf growth, and promotion of adventitious root formation. all three responses can be induced in isolated stem sections by treatment with ethylene. dose-response curves indicate that the responses are linearly related to the logarithm of the ethylene concentration over two orders of magnitude. application of the cyclic olefin 2,5-norbornadiene ( ... | 1987 | 16665450 |
| in vivo 1-aminocyclopropane-1-carboxylate synthase activity in internodes of deepwater rice : enhancement by submergence and low oxygen levels. | inasmuch as the activity of 1-aminocyclopropane-1-carboxylate (acc) synthase cannot be measured in homogenates of deepwater rice internodes (oryza sativa l.), we have employed an in vivo assay to determine the activity of this enzyme. this assay is based on the accumulation of acc in tissue kept under n(2). submergence of whole plants or stem sections containing the uppermost, developing internode enhances the in vivo activity of acc synthase in the stem. this stimulation of in vivo acc-synthase ... | 1987 | 16665431 |
| effect of sugar mill effluent on oxygen uptake and carbon dioxide output of rice (oryza sativa l.c.v. mushoori) seedlings. | the effects of a sugar mill effluent on respiration of rice (oryza sativa l.c.v. mushoori) seedlings have been investigated. each experiment consisted of two parts, the effect of various concentrations of the effluent and the time-dependent changes induced by the undiluted effluent. a marked increase in the rate of respiration was noticed upon treatment with various concentrations of the effluent. the time-dependent changes in the respiratory rate were about threefold with the 12 hr of treatment ... | 1987 | 3107978 |
| nuclear dna amplification in cultured cells of oryza sativa l. | highly repeated nuclear dna sequences from suspension cultured cells of oryza sativa l. cv. 'roncarolo' have been cloned in pbr322. ten clones with specific digestion patterns have been randomly selected. nine sequences appear to be organized in a clustered tandem array while one is interpersed in the rice genome. the clones have been used to gather information on: (a) their modulation in cultured cells as compared to whole plant and (b) their distribution in different rice cultivars belonging t ... | 1987 | 24241458 |
| a 5-methyltryptophan resistant rice mutant, mtr1, selected in tissue culture. | cell lines resistant to tryptophan analogue 5-methyltryptophan (5mt) were selected in seed-derived calli of oryza sativa l. var. 'norin 8'. plants were regenerated (r1 from one selected callus line (mtr1). in three out of the six r1 plants, 5mt resistance was inherited in the r2 and r3 generations as a dominant nuclear mutation. segregation ratios in the progeny of heterozygous plants were 1∶1. morphological and fertility variation seen in some of the r2 plants were not correlated with 5-methylt ... | 1987 | 24241455 |
| isozymes and classification of asian rice varieties. | enzyme variation detected by starch gel electrophoresis was used to investigate the genetic structure of oryza sativa l. species. fifteen polymorphic loci coding for 8 enzymes were surveyed among 1688 traditional rices from asia. multivariate analysis of the data resulted in identification of six varietal groups, with two major ones, groups i and vi, two minor ones, groups ii and v, and two satellite ones, groups iii and iv. group i is found throughout tropical asia; it encompasses most aman ric ... | 1987 | 24241451 |
| plant regeneration from in vitro cultures of anthers and mature seeds of rice (oryza sativa l.) cv. basmati-370. | pollen plants were obtained from anther-derived calli of the indica rice variety basmati-370. anther-response (anthers producing pollen derived calli) and plant regeneration frequency from the pollen derived calli. was very low. donor plants which flowered at the average max/min. temperature of 34.2°/23.3°c gave a significantly higher anther-response to in vitro techniques, than did those which flowered at 29.1°/16.4°c. somatic callus induction and subsequent plant regeneration was readily obtai ... | 1987 | 24248447 |
| genetic analysis of waxy locus in rice (oryza sativa l.). | inheritance of waxy locus was studied in crosses of a waxy variety with four non-waxy parents having high-, intermediate-, low- or very low-amylose content. the analysis for amylose content was done on a single grain basis in parents, f1, f2, b1f1, and b2f1 seeds. the waxy parent lacking synthesis of amylose content was found to differ from the ones having high-, intermediate-, low- or very low-amylose content by one gene with major effect. dosage effects for amylose content were observed to hav ... | 1987 | 24241102 |
| phosphorylation of thylakoid proteins of oryza sativa: in vitro characterization and effects of chilling temperatures. | the phosphorylation of thylakoid proteins of rice (oryza sativa l.) was studied in vitro using [gamma-(32)p]atp. several thylakoid proteins are labeled, including the light-harvesting complex of photosystem ii. protein phosphorylation is sensitive to temperature, ph, and adp, atp, and divalent cation concentrations. in the range ph 7 to 8.2, phosphorylation of the light-harvesting polypeptides declines above ph 7.5, whereas labeling of several other thylakoid polypeptides increases. increasing d ... | 1987 | 16665262 |
| differences between indica and japonica rice varieties in co2 exchange rates in response to leaf nitrogen and temperature. | four indica and five japonica varieties of rice (oryza sativa l.) were examined to elucidate their differences in photosynthetic activity and dark respiratory rate as influenced by leaf nitrogen levels and temperatures. the photosynthetic rates of single leaf showed correlations with total nitrogen and soluble protein contents in the leaves. respiratory rate was also positively correlated with the leaf nitrogen content. when compared at the same level of leaf nitrogen or soluble protein content, ... | 1987 | 24430670 |
| hirschmanniella spp. in rice fields of vietnam. | root and soil samples from one-crop and two-crop rice fields were collected in a survey for hirschmanniella spp. in vietnam during 1978-80. hirschmanniella spp. were found in 50-78% of the soil samples and 98-100% of the root samples collected. population densities of nematodes in root systems were lowest at posttransplanting and highest at heading time. numbers of nematodes inside roots increased 20-22 times from transplanting to heading in fields with both crop sequences. population densities ... | 1987 | 19290110 |
| biochemical and immunological characterization of rice albumin. | rice albumin from oryza sativa (var. basmati 370) accounts for about 5% of the total seed proteins. a major fraction of rice albumin has been found to be a glycoprotein which is a monomer of 60 kd having iso-electric point 6.54. when rice albumin is digested with trypsin, it shows the presence of 24 peptides as against 28 peptides which were estimated from its amino acid composition. this indicates the presence of a few peptides which resemble each other in their charge and rf values. antibodies ... | 1987 | 3620599 |
| the effect of submergence, ethylene and gibberellin on polyamines and their biosynthetic enzymes in deepwater-rice internodes. | submergence and treatment with ethylene or gibberellic acid (ga3) stimulates rapid growth in internodes of deepwater rice (oryza sativa l. cv. "habiganj aman ii"). this growth is based on greatly enhanced rate of cell-division activity in the intercalary meristem (im) and on increased cell elongation. we chose polyamine biosynthesis as a biochemical marker for cell-division activity in the im of rice stems. upon submergence of the plant, the activity of s-adenosylmethionine decarboxylase (samdc; ... | 1986 | 24232756 |
| anatomical analysis of growth and developmental patterns in the internode of deepwater rice. | submergence of the stem induces rapid internodal elongation in deepwater rice (oryza sativa l. cv. "habiganj aman ii"). a comparative anatomical study of internodes isolated from airgrown and partially submerged rice plants was undertaken to localize and characterize regions of growth and differentiation in rice stems. longitudinal sections were examined by light and scanning-electron microscopy. based on cell-size analysis, three zones of internodal development were recognized: a zone of cell d ... | 1986 | 24232755 |
| immunochemical studies on the role of the golgi complex in protein-body formation in rice seeds. | antibodies raised against purified glutelins and prolamines were employed as probes to study the cellular routes by which these proteins are deposited into protein bodies of rice (oryza sativa l.) endosperm. three morphologically distinct protein bodies, large spherical, small spherical, and irregularly-shaped, were observed, in agreement with existing reports. immunocytochemical studies showed the presence of glutelins in the irregularly-shaped protein bodies while the prolamines were found in ... | 1986 | 24232753 |
| isolation and hypoglycemic activity of oryzarans a, b, c, and d: glycans of oryza sativa roots. | | 1986 | 3562666 |
| extent of heterosis in rice (oryza sativa l.) under cold stress conditions - yield and its components. | the nature and extent of heterosis for grain yield and its component characters was estimated in a seven-parent f1-diallel cross in rice under the cold stress conditions of palampur, representing sub-temperate climate of the mid hills of himachal pradesh. the highest heterotic effects for grain yield were observed in 'himalaya 1'/'phul patas 72' and 'china 988'/'himdhan' hybrids, which gave 60.36 and 32.48% heterosis, respectively, over mid parent, 38.76 and 26.86% heterosis, respectively, over ... | 1986 | 24240759 |
| regeneration of plants from long-term cultures of oryza sativa l. | root and embryo derived callus tissues of rice grown on sucrose alone as carbon source lost their ability to organise shoots by 75 and 100 days in culture respectively. along with 2% sucrose, either 3% sorbitol or 3% mannitol was found to be necessary in the growth medium for the callus to regenerate whole plants over a period of 1400 days without any decline in the shoot forming ability. our results indicated that incorporation of sorbitol or mannitol in the callus proliferating medium provides ... | 1986 | 24248307 |
| heat inactivation of starch synthase in wheat endosperm tissue. | the effect of temperature on accumulation of starch was studied in grain slices of wheat (triticum aestivum cv sun9e), taken 15 days after anthesis. as compared with pretreatment of such slices at 25 degrees c, pretreatment at 30 or 35 degrees c reduced the subsequent conversion of sucrose to starch. in contrast to rice (oryza sativa cv calrose), pretreatment of wheat soluble starch synthase in vitro at 30 degrees c or higher temperatures reduced its activity. in zymograms using nondenaturing po ... | 1986 | 16664836 |
| anther culture in rice: iv. the effect of abscisic acid on plant regeneration. | the effect of abscisic acid (aba) on plant regeneration in anther-derived calli of rice oryza sativa l. varieties taipei 177, taipei 309 and fujisaka 5 was studied.aba at concentrations up to 4×10(-6) m stimulated fresh weight increase in taipei 309 and fujisaka 5 while higher concentrations effected corresponding weight decreases in the three varieties tested. relatively high aba concentrations resulted in decreased callus size and production of more compact and whitish calli. aba increased the ... | 1986 | 24248053 |
| cytochemical studies of callus development from microspore in cultured anther of rice. | cytochemical studies of androgenic anthers of oryza sativa picked from the culture at 2 day intervals from 0 to 40 days have been carried out. glutaradehyde-oso4-fixed and plastic-embedded sections were stained with tbo, sbb and pas for acidic polymers, lipids and polysaccharides respectively. among the population only 4% of microspores, which accumulate abundant amorphous lipid in the first few days of culture, are androgenic. less than 30%, which have many lipid granules and some amorphous lip ... | 1986 | 24248049 |
| plant regeneration and initiation of cell suspensions from root-tip derived callus of oryza sativa l. (rice). | root-tip derived suspended callus of oryza sativa cv. thaipei showed the capacity for plant regeneration via organogenesis. cell cultures were induced in liquid murashige-skoog medium containing 2 mg/l 2.4-dichlorophenoxyacetic acid. dicamba or picloram were effective for induction of organogenesis. shoots and roots differentiated following subculture on medium lacking auxins but containing kinetin. at 1 and 4 mg/l dicamba and 1 mg/l picloram normal green plants were regenerated whereas with 7 m ... | 1986 | 24248041 |
| plant regeneration from protoplast-derived callus of rice (oryza sativa l.). | protoplasts isolated from cultured rice cells of an a-58 cytoplasmic male sterile line (a-58 ms)(oryza sativa l.) were used to investigate the regeneration of rice plants. a cultured cell line (t3) of a-58 ms with a high growth rate and dense cytoplasm was selected. about 10% of the protoplasts prepared from this established cell line plated in ry-2 (a new medium) formed colonies. the calli formed shoots and roots in the regeneration medium and developed into whole plants.protoplasts also were p ... | 1986 | 24248040 |
| genotypic variability for callus formation and plant regeneration in rice (oryza sativa l.). | 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 callu ... | 1986 | 24247763 |
| detection of the messenger rna encoding for the ferredoxin-dependent glutamate synthase in maize leaf. | ferredoxin-dependent glutamate synthase (ec 1.4.7.1), glutamate oxoglutarate aminotransferase (glutamate synthase) (gogat) messenger rna was extracted from maize (zea mays l.) leaves and partially purified through oligo(dt)-cellulose chromatography and ultracentrifugation in a sucrose gradient. mrna were translated in vitro using a reticulocyte system. the glutamate synthase subunit was characterized by immunoprecipitation with antibodies raised against the rice (oryza sativa l.) ferredoxin-glut ... | 1986 | 16664732 |
| non-proline-accumulating rice mutants resistant to hydroxy-l-proline. | three rice (oryza sativa l.) mutants resistant to hydroxy-l-proline (hyp), hyp 101, hyp 202 and hyp 203, were selected from an ethylene imine mutagenized m2 population of the original variety, 'nipponbare', and their biochemical and genetical characteristics were investigated. the sensitivity of the mutants to hyp could be clearly differentiated from that of the original variety when seeds were germinated and cultured with 10(-4)∼10(-3) m hyp for 10 days. a difference in hyp sensitivity was also ... | 1986 | 24247838 |
| in vitro characterization of salt stress effects and the selection of salt tolerant plants in rice (oryza sativa l.). | the response of plant cells to salt stress was studied on embryo derived calli of rice (oryza sativa l.) in order to identify cellular phenotypes associated with the stress. the feasability of selecting salt tolerant callus and its subsequent regeneration to plants was also studied. callus was grown on agar-solidified media containing 0%, 1% and 2% (w/v) nacl for 24 days. parameters such as fresh weight, dry weight, soluble protein and proline content were measured. the callus growth decreased m ... | 1986 | 24247613 |
| seed dormancy in red rice : v. response to azide, hydroxylamine, and cyanide. | the activity of nan(3) (0.5 millimolar), hydroxylamine-hcl (10-18 millimolar), and potassium cyanide (1 millimolar) as dormancy-breaking agents of dehulled red rice (oryza sativa) is ph-dependent such that medium ph values favoring formation of the uncharged chemical species resulted in the highest germination percentages. there was no promotive effect of ph itself in the range of 3 to 10. the minimum contact times for maximum response (>/=90% germination) to nan(3), kcn, and nh(2)oh-hcl are 8 h ... | 1986 | 16664656 |
| nucleotide sequence of the rice cytochrome f gene and the presence of sequence variation near this gene. | the rice (oryza sativa l. var. labelle) chloroplast (cp) gene encoding cytochrome f has been isolated and sequenced. the coding region of this rice gene displays 95.1%, 85.3% and 85.2% nucleotide sequence homology with that of wheat, pea and spinach, respectively. to examine the cpdna sequence variation in rice, cpdna from labelle and its parents, belle patna and dawn was compared. using the cytochrome f gene as the probe for hybridization, we found several differences in the size and number of ... | 1986 | 2884170 |
| cytogenetical analysis on aneuploids obtained from pollenclones of rice (oryza sativa l.). | rice aneuploids were obtained from 1,715 pollenclones with a mean frequency of 10.2% in anther culture (1983 to 1985). among the aneuploids obtained, the frequency of primary trisomics ranged from 5.4% to 6,7%, tetrasomics from 1.1% to 1.7% monosomics from 0.9% to 1.3%, nullisomics from 0.5% to 1% and double trisomics from 0.5% to 0.7%. the chromosome complements of those aneuploids were identified by pachytene analysis on the absolute length of the extra chromosomes. pollen clonal aneuploids sh ... | 1985 | 24247462 |
| photosynthesis and ribulose-1,5-bisphosphate carboxylase/oxygenase in rice leaves from emergence through senescence. quantitative analysis by carboxylation/oxygenation and regeneration of ribulose 1,5-bisphosphate. | changes in gas-exchange rates during the life span of the leaves of rice (oryza sativa l.) were analyzed quantitatively by measuring changes in the carboxylation/oxygenation and regeneration of ribulose 1,5-bisphosphate (rubp) at photon fluence rates of 2000 (saturating) and 500 (subsaturating) μmol quanta·m(-2)·s(-1) under ambient air conditions. the rubp levels were always higher than the active-site concentrations of rubp carboxylase (ec 4.1.1.39), irrespective of the irradiance supplied. ana ... | 1985 | 24241526 |
| genetic divergence among some maintainer and restorer lines in relation to hybrid breeding in rice (oryza sativa l.). | a representative group of 100 elite lines, 67 of which are restorers and 33 maintainers, from 68 crosses made at irri and 18 improved varieties from five countries were studied, using mahalonobis, d(2)-statistic and canonical analysis, to understand the nature and magnitude of divergence and to assess the importance of a set of quantitative characters related to yield in genetic differentiation. the 100 genotypes were grouped into 13 clusters. there were three single variety clusters and the num ... | 1985 | 24253127 |