| culture of and fertile plant regeneration from regenerable embryogenic suspension cell-derived protoplasts of wheat (triticum aestivum l.). | regenerable embryogenic cell suspensions initiated from immature embryo-derived friable, fast growing, embryogenic calli of gk ságvári winter wheat (triticum aestivum l.) served as sources of protoplasts, which were cultured in different liquid or agarose-solidified media. protocallus formation was best on km8p (kao and michayluk 1975) and gm (li and murai 1990) media, and protocallus growth on ms (murashige and skoog 1962) callus growing medium. green shoot/plant regeneration occurred on ms reg ... | 1993 | 24196857 |
| plant regeneration from isolated microspores of triticum aestivum. | wheat microspores were isolated, without prior anther culture, from a range of genotypes and cultured to regenerate self-fertile plants. microspores were isolated using a microblender and competent microspores were enriched by gradient centrifugation. the use of maltose as the sole carbohydrate in the culture medium and co-culture of microspores with wheat or barley ovaries were critical for development of microspore-derived embryos. results were also improved when spikes were pretreated by emer ... | 1993 | 24196852 |
| pedigree assessment using rapd-dgge in cereal crop species. | the introduction of molecular biology methodologies to plant improvement programs offers an invaluable opportunity for extensive germplasm characterization. however, the detection of adequate dna polymorphism in self-pollinating species remains on obstacle. we have optimized a denaturing-gradient-gel electrophoresis (dgge) system which, when used in combination with random amplified polymorphic dna (rapd) analysis, greatly facilitates the detection of reproducible dna polymorphism among closely ... | 1993 | 24195921 |
| the effects of lead-resistant pseudomonads on the growth of triticum aestivum seedlings under lead stress. | five pseudomonad strains, spb-1, spb-2, spb-3, (from a water sample), spb-4, and spb-5 (from rhizosphere), which could tolerate lead acetate up to 1000 microm ml(-1), were isolated from an industrially polluted area around kasoor, pakistan. only spb-5 harbours a lead-resistant plasmid. triticum aestivum seeds inoculated with strains spb-4 and spb-5 were germinated and grown under different concentrations (0, 1, 5, 10, 15 and 20 mm) of lead acetate for ten days. germination and seedling growth we ... | 1993 | 15091828 |
| a data base of crop nutrient use, water use, and carbon dioxide exchange in a 2o square meter growth chamber: i. wheat as a case study. | a data set is given describing the daily nutrient uptake, gas exchange, environmental conditions, and carbon (c), and nutrient partitioning at harvest for the entire canopy and root system of a wheat crop (triticum aestivum, cv. yecora rojo). the data were obtained from a 20 m2 stand of wheat plants grown from planting to maturity in a closed, controlled environment, and include daily nutrient uptake [macronutrients, nitrogen (n), phosphorus (p), potassium (k), calcium (ca), magnesium (mg), and ... | 1993 | 11538007 |
| cytoplasmic male sterility and fertility restoration in wheat are not associated with rearrangements of mitochondrial dna in the gene regions for cob, coxii, or coxi. | in comparing the genetic organization and exploring the molecular basis of cytoplasmic male sterility (cms) in wheat, mitochondrial dnas (mtdna) from triticum aestivum, t. timopheevi, cms alloplasmic wheat with t. aestivum nucleus and t. timopheevi mitochondria, and fertility-restored lines were compared by hybridization analysis with specific probes for three gene regions: coxii, cob, and coxi. minor differences between t. aestivum- and t. timopheevi-derived sources were found for gene regions ... | 1993 | 8425048 |
| high-efficiency plant regeneration from an embryogenic cell suspension culture of winter wheat (triticum aestivum l.). | highly embryogenic cell suspension cultures were established from immature embryo-derived embryogenic calli of winter wheat (triticum aestivum l., cv. gk ságvári). weekly subcultures were made in liquid ms medium supplemented with 2 mg 1(-1) 2,4-d. an average of twenty-two compact, organized calli were obtained from each 1 ml suspension cells when plated on solid ms medium containing iaa and zeatin under a 16/8 h light/dark cycle, while only 9 calli were produced in the dark. variation in the ca ... | 1993 | 7871929 |
| short-term experiments on ion transport by seedlings and excised roots : technique and validity. | the absorption of k(+) by excised roots of barley (hordeum vulgare l. cv california mariout) has been systematically compared with that of entire, undisturbed seedlings. some experiments have also been done with wheat (triticum aestivum l.) and an amphiploid obtained from a cross between it and salt-tolerant tall wheatgrass (lophopyrum elongatum host löve [syn. agropyron elongatum host]). for all three genotypes, the rate of k(+) absorption measured in a 20-min period was identical for entire 8- ... | 1992 | 16653217 |
| phenotypic analysis of a dwarf wheat (triticum aestivum l.) with altered phytochrome-mediated growth responses. | the influence of the amount of red light relative to far red light (red/far red ratio) on leaf-sheath elongation, leaf length, tillering, assimilate partitioning to shoots and roots, and chlorophyll content in a dwarf wheat (triticum aestivum l. cv tibet dwarf) and seven other dwarf and standard cultivars was determined. all cultivars tested showed far red-stimulated leaf and leaf-sheath elongation except tibet dwarf. tibet dwarf was also unresponsive to a brief end-of-day exposure to far red li ... | 1992 | 16653215 |
| identification of embryoid-abundant genes that are temporally expressed during pollen embryogenesis in wheat anther cultures. | uninucleate microspores in anther cultures of bread wheat (triticum aestivum cv pavon) are capable of producing haploid pollen embryoids and plants. to gain an understanding of this alternate pathway of pollen development, we constructed a cdna library to young pollen embryoids, isolated embryoid-specific genes, and analyzed their expression patterns during morphogenesis. two embryoid-abundant clones, pemb4 and 94, were expressed very early during culture, suggesting that these genes are associa ... | 1992 | 16653192 |
| fructo-oligosaccharides from the stems of triticum aestivum. | fructo-oligosaccharides, extracted with hot water from wheat stems before flowering, were fractionated by gel-permeation chromatography on biogel p2. the tri-/tetra- and penta-saccharide fractions were purified by hplc and analysed by the reductive cleavage method. the trisaccharides 1-kestose and 6-kestose, the branched tetrasaccharide bifurcose, and the (2-->6)-linked pentasaccharide were identified. the fractions of higher molecular weight were also investigated and confirmed the branched-lev ... | 1992 | 1473106 |
| the location of major genes and associated quantitative trait loci on chromosome arm 5bl of wheat. | chromosome 5b of bread wheat is known to carry two major genes giving rise to genetic disorders, ne1 for hybrid necrosis and vg for winter variegation. additionally, in many european winter wheat varieties this chromosome is represented in a translocated form, with 5bl-7bl, 5bl-7bs chromosomes rather than the normal 5b and 7b forms of the standard variety chinese spring. genetic analysis has been carried out to map these genes and the translocation break point, and to investigate their pleiotrop ... | 1992 | 24197305 |
| evidence against the regulation of grain set by spikelet abscisic acid levels in water-stressed wheat. | a possible role of abscisic acid (aba) in the regulation of grain set in water-stressed wheat (triticum aestivum l.) was investigated using a split root system to dry half the roots while the remainder were kept watered. water uptake by the wet roots maintained the leaf water potential at the normal level, whereas the aba produced in the dry roots was transported to the spike. this caused the spikelet aba level to increase to the same extent as when the entire root system was stressed to permit ... | 1992 | 16653167 |
| turnover of soluble proteins in the wheat sieve tube. | although the enucleate conducting cells of the phloem are incapable of protein synthesis, phloem exudates characteristically contain low concentrations of soluble proteins. the role of these proteins and their movement into and out of the sieve tubes poses important questions for phloem physiology and for cell-to-cell protein movement via plasmodesmata. the occurrence of protein turnover in sieve tubes was investigated by [(35)s]methionine labeling and by the use of aphid stylets to sample the s ... | 1992 | 16653142 |
| endogenous rhythmicity of ethylene production in growing intact cereal seedlings. | ethylene evolution from etiolated barley (hordeum vulgare), wheat (triticum aestivum), and rye (secale cereale) seedlings during coleoptile growth followed a rhythmic pattern, with a period of about 16 h for barley and wheat and 12 h for rye seedlings. leaf emergence disturbed the established rhythm of ethylene evolution. | 1992 | 16653134 |
| coordinate gene response to salt stress in lophopyrum elongatum. | lophopyrum elongatum is a highly salt-tolerant relative of wheat. a previous study showed that the abundance of a number of mrna species is enhanced or reduced in the roots of the l. elongatum x triticum aestivum amphiploid by salt stress. eleven genes with enhanced expression in the roots of salt-stressed l. elongatum plants have been cloned as cdnas. the clones were used as probes to characterize temporal expression of these genes in roots after initiation of salt (250 mm nacl) stress. all 11 ... | 1992 | 16653133 |
| polyphosphoinositide phospholipase c in plasma membranes of wheat (triticum aestivum l.) : orientation of active site and activation by ca and mg. | polyphosphoinositide-specific phospholipase c activity was present in plasma membranes isolated from different tissues of several higher plants. phospholipase c activities against added phosphatidylinositol 4-phosphate (pip) and phosphatidylinositol 4,5-bisphosphate (pip(2)) were further characterized in plasma membrane fractions isolated from shoots and roots of dark-grown wheat (triticum aestivum l. cv drabant) seedlings. in right-side-out (70-80% apoplastic side out) plasma membrane vesicles, ... | 1992 | 16653120 |
| effect of cold hardening on sensitivity of winter and spring wheat leaves to short-term photoinhibition and recovery of photosynthesis. | photoinhibition of photosynthesis and its recovery were studied in wheat (triticum aestivum l.) leaves grown at nonhardening (20 degrees c) and cold-hardening (5 degrees c) temperatures. cold-hardened wheat leaves were less susceptible to photoinhibition at 5 degrees c than nonhardened leaves, and the winter cultivars, kharkov and monopol, were less susceptible than the spring cultivar, glenlea. the presence of chloramphenicol, a chloroplastic protein synthesis inhibitor, increased the susceptib ... | 1992 | 16653118 |
| analysis of light-induced depressions of photosynthesis in leaves of a wheat crop during the winter. | the photosynthetic performances of individual leaves of a wheat (triticum aestivum cv bezostaya) crop were assessed daily and throughout individual days during the winter when temperature and light levels were fluctuating. measurements of chlorophyll fluorescence induction and the maximum quantum yield of o(2) evolution were made on individual leaves. depressions in the ratio of variable to maximal fluorescence (f(v)/f(m)) were correlated with low temperatures and high light levels throughout th ... | 1992 | 16653108 |
| the modification of a common wheat-thinopyrum distichum translocated chromosome with a locus homoeoallelic to lr19. | the 'chinese spring' ph1b and ph2b mutants, as well as the nulli 5b tetra 5d stock were utilized in an attempt to effect homoeologous chromatin exchange between the 'indis' chromosome translocation [derived from thinopyrum distichum (thunb.) löve] and chromosome arm 7dl of common wheat. a homoeoallele of lr19 and linked genes for yellow flour-pigmentation were utilized as markers. seven selections with recombinations involving the foreign, translocated segment were recovered. four of these had w ... | 1992 | 24197231 |
| aluminum effects on the kinetics of calcium uptake into cells of the wheat root apex : quantification of calcium fluxes using a calcium-selective vibrating microelectrode. | the effects of aluminum on the concentration-dependent kinetics of ca(2+) uptake were studied in two winter wheat (triticum aestivum l.) cultivars, al-tolerant atlas 66 and al-sensitive scout 66. seedlings were grown in 100 μm cacl2 solution (ph 4.5) for 3 d. subsequently, net ca(2+) fluxes in intact roots were measured using a highly sensitive technique, employing a vibrating ca(2+)-selective microelectrode. the kinetics of ca(2+) uptake into cells of the root apex, for external ca(2+) concentr ... | 1992 | 24178332 |
| effect of long-term photoinhibition on growth and photosynthesis of cold-hardened spring and winter wheat. | the effect of repeated exposure to high light (1200 μmol · m(-2) · s(-1) photosynthetic photon flux density, ppfd) at 5° c was examined in attached leaves of cold-grown spring (cv. katepwa) and winter (cv. kharkov) wheat (triticum aestivum l.) over an eight-week period. under these conditions, kharkov winter wheat exhibited a daily reduction of 24% in fv/fm (the ratio of variable to maximal fluorescence in the dark-adapted state), in contrast to 41% for cold-grown katepwa spring wheat. both cult ... | 1992 | 24178327 |
| cell shape and localisation of ice in leaves of overwintering wheat during frost stress in the field. | wheat leaf pieces were excised and freeze-fixed in the field, preparatory to low-temperature scanning electron microscopy to study distribution of ice within leaf blades, and associated cell shapes, during natural frosts. pieces of leaf blades from wheat plants (triticum aestivum l. 7942h1-20-8) overwintering in indiana, usa (january, 1991), were excised and immediately freeze-fixed by manually plunging in melting freon. cells in controls were turgid and extracellular ice was absent. the leaves ... | 1992 | 24178321 |
| tolerance to imidazolinone herbicides in wheat. | an imidazolinone-tolerant wheat (triticum aestivum l. em thell) mutant in the winter wheat cultivar fidel has been identified and characterized. the mutant was isolated from a population derived through seed mutagenesis of the variety with an aqueous solution containing sodium azide. imidazolinone-tolerant wheat seedlings were selected from the m(2) generation of the population in the presence of imazethapyr herbicide and identified as herbicide-insensitive individuals. the trait is inherited as ... | 1992 | 16653071 |
| aryl hydroxylation of the herbicide diclofop by a wheat cytochrome p-450 monooxygenase : substrate specificity and physiological activity. | wheat (triticum aestivum l. cv etoile de choisy) microsomes catalyzed the cytochrome p-450-dependent oxidation of the herbicide diclofop to three hydroxy-diclofop isomers. hydroxylation was predominant at carbon 4, with migration of chlorine to carbon 5 (67%) and carbon 3 (25%). the 2,4-dichloro-5-hydroxy isomer was identified as a minor reaction product (8%). substrate-specificity studies showed that the activity was not inhibited or was weakly inhibited by a range of xenobiotic or physiologica ... | 1992 | 16653070 |
| cytochrome p-450-dependent hydroxylation of lauric acid at the subterminal position and oxidation of unsaturated analogs in wheat microsomes. | microsomes from etiolated wheat (triticum aestivum l. cv etoile de choisy) shoots catalyzed the reduced nicotinamide adenine dinucleotide phosphate-dependent hydroxylation of lauric acid predominantly at the subterminal or (omega-1) position (65%). minor amounts of 10-hydroxy- (31%) and 9-hydroxylaurate (4%) were also formed. the reaction was catalyzed by cytochrome p-450, since enzyme activity was strongly inhibited by tetcyclacis, carbon monoxide, and antibodies against nadph-cytochrome c (p-4 ... | 1992 | 16653069 |
| effects of water-deficit stress on photosynthesis, its components and component limitations, and on water use efficiency in wheat (triticum aestivum l.). | it is of theoretical as well as practical interest to identify the components of the photosynthetic machinery that govern variability in photosynthesis rate (a) and water-use efficiency (wue), and to define the extent by which the component processes limit a and wue during developing water-deficit stress. for that purpose, leaf exchange of co(2) and h(2)o was determined in two growth-chamber-grown wheat cultivars (triticum aestivum l. cv tam w-101 and cv sturdy), and the capacity of a was determ ... | 1992 | 16653053 |
| nucleotide sequence of the internal transcribed spacer region of rdna in wheat, triticum aestivum l. (gramineae). | | 1992 | 1515605 |
| c-banding and in-situ hybridization analyses of agropyron intermedium, a partial wheat x ag. intermedium amphiploid, and six derived chromosome addition lines. | c-banded karyotypes of agropyron intermedium (2n=6x=42, e1e2x), a partial amphiploid triticum aestivum -ag. intermedium (2n=8x=56, taf46), and six derived chromosome addition lines, were analyzed. in ag. intermedium, diagnostic c-bands were present on 14 pairs of chromosomes, designated from a to n, while the remaining seven pairs, designated o to u, either lacked, or had only faint, c-bands and were not always identified unambiguously. all seven ag. intermedium chromosome pairs of the partial a ... | 1992 | 24201492 |
| genomic in situ hybridization to identify alien chromosomes and chromosome segments in wheat. | genomic in situ hybridization was used to identify alien chromatin in chromosome spreads of wheat, triticum aestivum l., lines incorporating chromosomes from leymus multicaulis (kar. and kir.) tzvelev and thinopyrum bessarabicum (savul. and rayss) löve, and chromosome arms from hordeum chilense roem. and schult, h. vulgare l. and secale cereale l. total genomic dna from the introgressed alien species was used as a probe, together with excess amounts of unlabelled blocking dna from wheat, for dna ... | 1992 | 24201474 |
| nitrate activation of cytosolic protein kinases diverts photosynthetic carbon from sucrose to amino acid biosynthesis: basis for a new concept. | the regulation of carbon partitioning between carbohydrates (principally sucrose) and amino acids has been only poorly characterized in higher plants. the hypothesis that the pathway of sucrose and amino acid biosynthesis compete for carbon skeletons and energy is widely accepted. in this review, we suggest a mechanism involving the regulation of cytosolic protein kinases whereby the flow of carbon is regulated at the level of partitioning between the pathways of carbohydrate and nitrogen metabo ... | 1992 | 16653003 |
| operationally defined apoplastic and symplastic aluminum fractions in root tips of aluminum-intoxicated wheat. | knowledge of the mechanistic basis of differential aluminum (al) tolerance depends, in part, on an improved ability to quantify al located in the apoplastic and symplastic compartments of the root apex. using root tips excised from seedlings of an al-tolerant wheat cultivar (triticum aestivum l. cv yecora rojo) grown in al solutions for 2 d, we established an operationally defined apoplastic al fraction determined with six sequential 30-min washes using 5 mm cacl(2) (ph 4.3). soluble symplastic ... | 1992 | 16652962 |
| purification and characterization of wheat beta(2-->1) fructan:fructan fructosyl transferase activity. | fructans are the major storage carbohydrate in vegetative tissues of wheat (triticum aestivum l.). fructan:fructan fructosyl transferase (fft) catalyzes fructosyl transfer between fructan molecules to elongate the fructan chain. the objective of this research was to isolate this activity in wheat. wheat (cv caldwell) plants grown at 25 degrees c for 3 weeks were transferred to 10 degrees c to induce fructan synthesis. from the leaf blades kept at 10 degrees c for 4 days, fructosyl transferase ac ... | 1992 | 16652946 |
| effect of alpha-gliadin-derived peptides from bread and durum wheat on k562(s) cells. | previous studies suggested that the proteins and peptides that are responsible for coeliac small intestinal lesions, are also able to agglutinate k562(s) cells. on the contrary, peptides from whole gliadins from durum (tetraploid) wheat do not agglutinate these cells. bread wheat alpha-gliadins have been identified as a major toxic fraction in coeliac disease. in the present research, alpha-gliadins were purified from durum and bread wheat cultivars. alpha-gliadin peptides from bread wheat were ... | 1992 | 1392022 |
| production and cytogenetic analysis of bc1, bc 2, and bc 3 progenies of an intergeneric hybrid between triticum aestivum (l.) thell. and tetraploid agropyron cristatum (l.) gaertn. | intergeneric hybrids between triticum aestivum cv 'chinese spring' and agropyron cristatum 4x (2n= 5x=35, abdpp genomes) with a high level of homoeologous meiotic pairing between the wheat chromosomes were backcrossed 3 times to wheat. pollination of the f1 hybrid with 'chinese spring' resulted in 22 bc1 seeds with an average seed set of 1.52%. five bc1 plants with 39-41 chromosomes were raised using embryo rescue techniques. chromosome pairing in the bc1 was characterized by a high frequency of ... | 1992 | 24201360 |
| detection of dna sequence polymorphisms among wheat varieties. | a dna marker detection strategy that allows the rapid, efficient resolution of high levels of polymorphism among closely related lines of common wheat (triticum aestivum) has been developed to circumvent the apparent lack of restriction fragment length polymorphism in many important self-pollinated crop species. the technique of randomly amplified polymorphic dna (rapd) was combined with a denaturing gradient gel electrophoresis system (dgge) to explore dna sequence polymorphisms among different ... | 1992 | 24201343 |
| moderately repeated, dispersed, and highly variable (mrdhv) genomic sequences of common wheat usable for cultivar identification. | a 4.1-kb dna clone (ptag546), which when used as a probe produces hypervariable dna fingerprints in common wheat, was found among the genomic clones of triticum aestivum cv 'chinese spring'. nulli-tetrasomic analyses revealed that the sequences hybridizing to this clone were located at 12 loci on ten chromosomes of the a, b, and d genomes of common wheat. the complete nucleotide sequence of ptag546 was shown to have a transposable element-like structure within it, though no open reading frame wa ... | 1992 | 24201338 |
| isozyme and cytological markers of some psathyrostachys juncea accessions. | psathyrostachys juncea (synonymous to elymus junceus; 2n=2x=14, nn) has unique biotic and abiotic attributes that could contribute towards wheat improvement. the effectiveness of such an intergeneric hybridization program depends greatly on being able to establish diagnostic markers of the alien chromosomes. isoelectric focusing (ief) analyses of six enzyme systems have identified five biochemical markers - malate dehydrogenase (mdh), esterase (est), shikimate dehydrogenase (skdh), phosphoglucom ... | 1992 | 24201337 |
| wheat vegetative nitrogen compositional changes in response to reduced reproductive sink strength. | n redistribution patterns and the n composition of vegetative tissues above the peduncle node of wheat (triticum aestivum l.) plants with altered reproductive sink strength were evaluated to determine the role of vegetative storage proteins in the temporary storage of excess n destined for export. the degree of leaf senescence symptoms (loss of chlorophyll, total n, and ribulose-1,5-bisphosphate carboxylase/oxygenase) were initially reduced, but the complete senescence of vegetative tissues proc ... | 1992 | 16669060 |
| interactive effects of al, h, and other cations on root elongation considered in terms of cell-surface electrical potential. | the rhizotoxicities of al(3+) and of la(3+) to wheat (triticum aestivum l.) were similarly ameliorated by cations in the following order of effectiveness: h(+) approximately c(3+) > c(2+) > c(1+). among tested cations of a given charge, ameliorative effectiveness was similar except that ca(2+) was slightly more effective than other divalent cations and h(+) was much more effective than other monovalent cations. h(+) rhizotoxicity was also ameliorated by cations in the order c(3+) > c(2+) > c(1+) ... | 1992 | 16669059 |
| molecular and physiological analysis of a heat-shock response in wheat. | we have isolated two cdna clones from wheat (triticum aestivum l. var stephens), designated whsp16.8 and whsp16.9, that are highly similar in sequence to the low molecular weight heat-shock protein genes previously isolated from soybean. rna blot analysis confirms that these sequences are present in heat-shocked wheat seedlings, but not in control tissues. the whsp16.8 and whsp16.9 cdnas were isolated by screening a lambda gt11 expression library with antibodies to hmgc (a chromosomal protein of ... | 1992 | 16669058 |
| geographical variation in heading characters among wheat landraces, triticum aestivum l., and its implication for their adaptability. | heading time and its constituent traits, photoperiodic response, narrow-sense earliness and vernalization requirement, were surveyed for 158 wheat landraces. wide varietal variation was observed in each character. nearly half of the variation for each character was explained by a geographical difference in origin. based on these data and the growing environments in each locality, we analyzed "adaptation strategy", seen as the adjustment of heading time in terms of differences in the constituent ... | 1992 | 24203181 |
| aluminum toxicity in roots : correlation among ionic currents, ion fluxes, and root elongation in aluminum-sensitive and aluminum-tolerant wheat cultivars. | the inhibition of root growth by aluminum (al) is well established, yet a unifying mechanism for al toxicity remains unclear. the association between cell growth and endogenously generated ionic currents measured in many different systems, including plant roots, suggests that these currents may be directing growth. a vibrating voltage microelectrode system was used to measure the net ionic currents at the apex of wheat (triticum aestivum l.) roots from al-tolerant and al-sensitive cultivars. we ... | 1992 | 16668988 |
| aluminum partitioning in intact roots of aluminum-tolerant and aluminum-sensitive wheat (triticum aestivum l.) cultivars. | aluminum (al) partitioning in intact roots of wheat (triticum aestivum l.) cultivars that differ in sensitivity to al was investigated. roots of intact seedlings were exposed to al for up to 24 hours and distribution of al was assessed visually by hematoxylin staining or by direct measurement of concentration of al by atomic absorption spectrophotometry or ion chromatography. major differences in al accumulation between al-tolerant (atlas 66) and al-sensitive (tam 105) cultivars were found in th ... | 1992 | 16668966 |
| plant regeneration from long term suspension culture-derived protoplasts of hexaploid wheat (triticum aestivum l.). | highly regenerable callus cultures have been obtained from immature embryos of hexaploid wheat cv. oderzo. friable fast growing calli were induced at high frequency. suspensions were initiated from the most friable callus lines: they became established in about two months. suspensions consisted of cell aggregates of 30 to 1000 um in diameter. upon plating on ms hormone-free medium, suspensions regenerated green plantlets, and their regenerative capability was maintained for at least 10 months. p ... | 1992 | 24203136 |
| water relations, gas exchange, and nutrient response to a long term constant water deficit. | wheat plants (triticum aestivum) were grown for 43 days in a micro-porous tube nutrient delivery system. roots were unable to penetrate the microporous tube, but grew on the surface and maintained capillary contact with the nutrient solution on the inside of the tube through the 5-micron pores of the porous tube. water potential in the system was controlled at -0.4, -0.8, and -3.0 kpa by adjusting the applied pressure (hydrostatic head) to the nutrient solution flowing through the microporous tu ... | 1992 | 11538048 |
| development of a chromosomal arm map for wheat based on rflp markers. | a chromosomal arm map has been developed for common wheat (triticum aestivum l. em. thell.) using aneuploid stocks to locate more than 800 restriction fragments corresponding to 210 low-copy dna clones from barley cdna, oat cdna, and wheat genomic libraries. the number of restriction fragments per chromosome arm correlates moderately well with relative dna content and length of somatic chromosomes. the chromosomal arm locations of loci detected with 6 different clones support an earlier hypothes ... | 1992 | 24202932 |
| factor regression for interpreting genotype-environment interaction in bread-wheat trials. | the french inra wheat (triticum aestivum l. em thell.) breeding program is based on multilocation trials to produce high-yielding, adapted lines for a wide range of environments. differential genotypic responses to variable environment conditions limit the accuracy of yield estimations. factor regression was used to partition the genotype-environment (ge) interaction into four biologically interpretable terms. yield data were analyzed from 34 wheat genotypes grown in four environments using 12 a ... | 1992 | 24202930 |
| evidence that aco-b2 and aco-d2 of triticum aestivum are located in chromosomes 4b and 4d. | studies designed to determine the chromosomal locations of variant aconitase-2 alleles of triticum aestivum disclosed that aco-b2 and aco-d2 are not located in chromosomes 5b and 5d, as formerly reported. reinvestigation of the chromosomal locations of the genes provided strong evidence they are instead located in chromosomes 4b and 4d. also, four aco-b2 alleles were identified but no variant aco-d2 alleles were detected. | 1992 | 24202929 |
| the influence of the rye genome on expression of heat shock proteins in triticale. | the heat shock protein profiles from secale cereale l. cv imperial, triticum aestivum l. cv chinese spring, s. cereale x t. aestivum amphiploid, and the seven disomic s. cereale addition lines to t. aestivum were used to compare the wheat, rye, and triticale heat shock protein profiles and to study the influence of the rye genome on heat shock protein expression in triticale. three-day-old seedlings were heat shocked for 2 h at 40 °c in the presence of (35)s-methionine, and polypeptides from roo ... | 1992 | 24202924 |
| no(3) enhances the kinase activity for phosphorylation of phosphoenolpyruvate carboxylase and sucrose phosphate synthase proteins in wheat leaves: evidence from the effects of mannose and okadaic acid. | the aim of this work was to determine which of the two reactions (i.e. phosphorylation or dephosphorylation) involved in the establishment of the phosphorylated status of the wheat leaf phosphoenolpyruvate carboxylase and sucrose phosphate synthase protein responds in vivo to no(3) (-) uptake and assimilation. detached mature leaves of wheat (triticum aestivum l. cv fidel) were fed with n-free (low-no(3) (-) leaves) or 40 mm no(3) (-) solution (high-no(3) (-) leaves). the specific inhibition of ... | 1992 | 16668874 |
| construction of a chromosome-enriched hpaii library from flow-sorted wheat chromosomes. | we report here the first successful generation of a chromosome-enriched library from flow sorted plant chromosomes. chromosomes with a characteristic dna content (a peak) were sorted from a synchronized cell culture (takb1, derived from triticum aestivum). a hpaii library was constructed from the sorted chromosomes and half of the cloned dna sequences analysed are unique or low copy. approximately half of these sequences when used as probes detect sequences on wheat chromosome 4a. the generation ... | 1992 | 1374560 |
| production and identification of three 4ag(4d) substitution lines of triticum aestivum - agropyron: relative transmission rate of alien chromosomes. | by crossing fertile nullisomics-4d of common wheat (nullisomics 72180 and 'tianxuan' no. 15) with three octoploid agrotriticum lines [partial amphiploids (2n=56) 78829 from the offsprings of wheat with agropyron intermedium (=thinopyrum intermedium, 2n=42) and 784 and 7631 from those of wheat with ag. elongatum (thinopyrum elongatum, 2n=70)], backcrossing the hybrid with 4d nullisomics as recurrent parent for one to two generations, and then selfing the bc individuals, we obtained three differen ... | 1992 | 24202744 |
| use of the polymerase chain reaction to detect spacer size heterogeneity in plant 5s-rrna gene clusters and to locate such clusters in wheat (triticum aestivum l.). | we have used the polymerase chain reaction to analyse variation in the size of individual 5s-ribosomal gene spacer sequences. this reaction can be used to demonstrate inter- and intraspecific variation in spacer size, and combined with dna sequencing it may thus be a valuable taxonomic tool. two sets of nested polymerase chain reaction primers were designed to amplify the nontranscribed spacer dna between repeated 5s-rrna genes. these "universal" primers were used to generate fragments from the ... | 1992 | 24202741 |
| long-term steady-state labelling of wheat plants by use of natural (13)co 2/ (12)co 2 mixtures in an open, rapidly turned-over system. | a photosynthate labelling method is presented which takes advantage of the natural difference in carbon-isotope composition (δ carbon-isotope composition of a sample is conventionally presented as δ (‰) = [(rp/rs) -1] · 1000, where rp and rs are the molar abundance ratios, (13)c/(12)c, of the sample and of the standard (pdb carbonate), respectively ) which exists between atmospheric co2 (δ≈-8‰) and commercially available compressed co2. carbon dioxide with δ-4.0 and -27.9%., respectively, has be ... | 1992 | 24177977 |
| gamma irradiation induced deletions in an alien chromosome segment of the wheat 'indis' and their use in gene mapping. | deletion mutants were produced in a translocated chromosome segment derived from thinopyrum distichum (thunb.) löve. spikes of the translocation line 'indis' were irradiated with gamma rays at dosages of 15, 20, and 25 gy. the irradiated spikes were pollinated with 'inia 66' pollen and the f2 and f3 generations screened for translocation mutants, using the genes for leaf rust resistance and yellow endosperm pigmentation as markers. finally, endopeptidase polymorphisms were utilized to select mut ... | 1992 | 1618387 |
| nucleotide sequence of a nuclear trna(tyr) gene from triticum aestivum. | | 1992 | 1600158 |
| zinc, a neurotoxin to cultured neurons, contaminates cycad flour prepared by traditional guamanian methods. | we have used cultured ventral mesencephalic and cerebellar granule cells to test the toxicity of extracts of cycad seeds (genus cycas) and cycad-derived flours traditionally prepared in guam. there was no significant difference in the toxicity of extracts prepared from the female gametophyte tissue of c. circinalis, c. revoluta, and c. media, common wheat flour, and 13 of 17 cycad flour samples. however, extracts prepared from 4 of 17 guamanian flour samples exhibited marked dose-dependent neuro ... | 1992 | 1556606 |
| variations in chloroplast proteins and nucleotide sequences of three chloroplast genes in triticum and aegilops. | two alloplasmic wheat lines having the same common wheat nucleus but the cytoplasms of aegilops crassa and ae. columnaris together with the corresponding normal line (control) were used in the two-dimensional gel electrophoresis of soluble and thylakoid membrane proteins of the chloroplast. three chloroplast polypeptides: the rubisco large subunit, the beta subunit of atp synthase, and an unidentified 31 kda protein, differed in the common wheat and two aegilops cytoplasms. three chloroplast gen ... | 1992 | 1388032 |
| embryogenic cell suspensions of triticum aestivum x leymus angustus f1 hybrids: characterization and plant regeneration. | embryogenic cell suspension cultures were established from triticum aestivum x leymus angustus f1 hybrids, using compact nodular calli derived from inflorescence segments. calli originating from leaf segments did not give rise to stable cell suspensions. growth measurements of the cell suspensions revealed that they continued rapid growth up to 10 days after subculturing. flow cytometric studies of the cell cycle over a 7 day culture period showed that the majority of cells were in g1 phase whil ... | 1992 | 24213490 |
| c-banding pattern and polymorphism of aegilops caudata and chromosomal constitutions of the amphiploid t. aestivum - ae. caudata and six derived chromosome addition lines. | c-banding patterns were analysed in 19 different accessions of aegilops caudata (= ae. markgrafii, = triticum dichasians) (2n = 14, genomically cc) from turkey, greece and the ussr, and a generalized c-banded karyotype was established. chromosome specific c-bands are present in all c-genome chromosomes, allowing the identification of each of the seven chromosome pairs. while only minor variations in the c-banding pattern was observed within the accessions, a large amount of polymorphic variation ... | 1992 | 24202675 |
| 5s ribosomal gene clusters in wheat: pulsed field gel electrophoresis reveals a high degree of polymorphism. | the long-range structure of 5s rrna gene clusters has been investigated in wheat (triticum aestivum l.) by means of pulsed field gel electrophoresis. using aneuploid stocks, 5s rrna gene clusters were assigned to sites on chromosomes 1b, 1d, 5b and 5d. cluster sizes were evaluated and the copy number of 5s dna repeats was estimated at 4700-5200 copies for the short repeating unit (410 bp) and about 3100 copies for the long repeat (500 bp) per haploid genome. a comparison of wheat cultivars revea ... | 1992 | 1557028 |
| block-surface staining for differentiation of starch and cell walls in wheat endosperm. | a staining technique for differentiating starch granules and cell walls was developed for computer-assisted studies of starch granule distribution in cells of wheat (triticum aestivum l.) caryopses. blocks of embedded caryopses were sectioned, exposing the endosperm tissue, and stained with iodine potassium iodide (iki) and calcofluor white. excessive tissue hydration during staining was avoided by using stains prepared in 80% ethanol and using short staining times. the iki quenched background f ... | 1992 | 1376154 |
| oxidative stress causes rapid membrane translocation and in vivo degradation of ribulose-1,5-bisphosphate carboxylase/oxygenase. | we have studied the turnover of an abundant chloroplast protein, ribulose-1,5-bisphosphate carboxylase/oxygenase (rbu-p2 carboxylase/oxygenase), in plants (spirodela oligorrhiza and triticum aestivum l.) and algae (chlamydomonas reinhardtii and c. moewusii) induced to senesce under oxidative conditions. rbu-p2 carboxylase/oxygenase activity and stability in vivo were found to be highly susceptible to oxidative stress, resulting in intermolecular cross-linking of large subunits by disulfide bonds ... | 1992 | 1733975 |
| relationship between pairing frequencies and genome affinity estimations in aegilops ovata × triticum aestivum hybrid plants. | meiotic associations at metaphase i have been analysed in aegilops ovata × triticum aestivum hybrid plants (genome constitution abdum) with low and high homoeologous pairing by using c-banding. five different types of meiotic associations involving aegilops and wheat genomes were identified. pairing affinities between aegilops and wheat genomes have been analysed from meiotic associations at metaphase i in low and high homoeologous pairing hybrid plants as well as from different meiotic configur ... | 1992 | 29231212 |
| plant regeneration from protoplasts of wheat (triticum aestivum cv. hartog). | morphologically normal green plants have reproducibly been regenerated from protoplasts of an australian wheat (triticum aestivum cv. hartog). the protoplasts were isolated from fine embryogenic suspension cultures which were initiated from embryogenic callus. protoplasts were incubated in a modified liquid ms medium containing half strength of the macroelements, 5 μm 2,4-d and 0.6 m glucose. colonies were formed at frequencies ranging from 0.1% to 5%. the frequency of colonies forming fully dev ... | 1992 | 24213030 |
| restriction fragment analysis of 'null' forms at the gli-1 loci of bread and durum wheats. | wheat accessions lacking some of the ω- and γ-gliadin components encoded by the gli-1 loci on the short arm of chromosome 1d in bread wheat and chromosome 1a in durum wheat were studied by two-dimensional polyacrylamide gel electrophoresis and restriction fragment analysis. digested genomic dnas of 'normal' and 'null' forms were probed with a cdna clone related to ω-/γ-gliadins and with a genomic clone encoding an lmw subunit of glutenin. the hybridisation patterns with the ω-/γ-gliadin probe we ... | 1992 | 24202588 |
| role of cytoskeleton in cell shaping of developing mesophyll of wheat (triticum aestivum l.). | the effects of oryzalin and cytochalasin b (cb) on microtubule and actin microfilament arrays and on cell shaping were investigated in developing wheat mesophyll. excised immature leaf sections capable of differentiating were incubated with the drugs. the behavior of the cytoskeleton was monitored by fluorescence microscopy after labeling with fluorescent dyes. brief incubation with oryzalin (40 min, 10 microm) caused disassembly of microtubules. recovery of microtubule arrays was comparatively ... | 1992 | 1639093 |
| diacylglycerol kinase in plasma membranes from wheat. | diacylglycerol kinase activity was demonstrated in highly purified plasma membranes isolated from shoots and roots of dark-grown wheat (triticum aestivum l.) by aqueous polymer two-phase partitioning. the active site of the diacylglycerol kinase was localized to the inner cytoplasmic surface of the plasma membrane using isolated inside-out and right-side-out plasma membrane vesicles from roots. the enzyme activity in plasma membrane vesicles from shoots showed a broad ph optimum around ph 7. the ... | 1992 | 1310876 |
| identification and chromosomal location of four subfamilies of the rubisco small subunit genes in common wheat. | three different 3' noncoding sequences of wheat rubisco small subunit (ssu) genes (rbcs) were used as probes to identify the gene members of different rbcs subfamilies in the common wheat cultivar chinese spring (cs). all genes of the wheat rbcs multigene family were previously assigned to the long arm of homoeologous group 5 and to the short arm of homoeologous group 2 chromosomes of cv cs. extracted dna from various aneuploids of these homoeologous groups was digested with four restriction enz ... | 1992 | 24202523 |
| analysis of hmw glutenin subunits encoded by chromosome 1a of bread wheat (triticum aestivum l.) indicates quantitative effects on grain quality. | a gene encoding the high-molecular-weight (hmw) subunit of glutenin 1ax1 was isolated from bread wheat cv hope. comparison of the deduced amino acid sequence with that previously reported for an allelic subunit, 1ax2(*), showed only minor differences, which were consistent with both subunits being associated with good bread-making quality. quantitative analyses of total protein extracts from 22 cultivars of bread wheat showed that the presence of either subunit 1ax1 or 1ax2(*), when compared wit ... | 1992 | 24202521 |
| a comparative evaluation of two methods of selecting locations used for testing spring wheat cultivars. | one of the considerations of regional cultivar evaluation programs is to optimize the number of locations used for testing. although optimization of numbers of locations using cluster analysis has been previously attempted, no objective comparison of methods has yet been made. a new clustering method that uses the pairwise contribution of locations to the cultivar x location mean square as the distance measure (lb) was compared to another method that employs diallel correlations as the distance ... | 1992 | 24202511 |
| the shibata shift and the transformation of etioplasts to chloroplasts in wheat with clomazone (fmc 57020) and amiprophos-methyl (tokunol m). | the shibata shift is a change in the absorption maximum of chlorophyllide from 684 to 672 nanometers that occurs within approximately 0.5 hour of phototransformation of protochlorophyllide to chlorophyllide. two compounds, clomazone and amiprophos-methyl, which previously have been shown to inhibit the shibata shift in vivo, were used to look for correlations between the shibata shift and other processes that occur during etioplast to chloroplast transformation. leaf sections from 6-day-old etio ... | 1992 | 16668622 |
| aluminum effects on calcium fluxes at the root apex of aluminum-tolerant and aluminum-sensitive wheat cultivars. | the role of ca(2+) transport in the mechanism of al toxicity was investigated, using a ca(2+)-selective microelectrode system to study al effects on root apical ca(2+) fluxes in two wheat (triticum aestivum l.) cultivars: al-tolerant atlas 66 and al-sensitive scout 66. intact 3-day-old low-salt-grown (100 micromolar cacl(2), ph 4.5) wheat seedlings were used, and it was found that both cultivars maintained similar rates of net ca(2+) uptake in the absence of al. addition of al concentrations tha ... | 1992 | 16668619 |
| function of photosynthetic apparatus of intact wheat leaves under high light and heat stress and its relationship with peroxidation of thylakoid lipids. | effects of high light and temperature stress on the structure and function of the photosynthetic apparatus of wheat (triticum aestivum) were studied. there was a decrease in the electron transport activity of chloroplasts isolated from photoinhibited and heat-stressed leaves. chlorophyll fluorescence was measured in photoinhibited and heat-stressed leaves and the decrease in variable fluorescence and variable to maximum fluorescence ratio of the stressed leaves indicated a loss in the quantum yi ... | 1992 | 16668597 |
| effects of air filtration on spring wheat grown in open-top field chambers at a rural site. ii. effects on mineral partitioning, sulphur and nitrogen metabolism and on grain quality. | in 1988 the effect of ambient levels of air pollutants on the nutrients status and grain quality of spring wheat (triticum aestivum cv. pelican) was investigated by comparing plants grown in open-top chambers (otc) ventilated with ambient air (nf treatments) and charcoal-filtered air (cf treatments) at a rural site (tervuren, belgium). spring wheat cultivated in nf otc showed only minor differences in the p, k, ca, mg, mn and na concentrations of the different plant parts at final harvest, as we ... | 1992 | 15091972 |
| effects of air filtration on spring wheat grown in open-top field chambers at a rural site. i. effects on growth, yield and dry matter partitioning. | spring wheat, triticum aestivum, was grown in open-top field chambers and exposed during the whole life cycle to filtered and non-filtered ambient air. the relatively low ambient pollution level did affect plant growth but had no effect on the overall grain yield of the two spring wheat cultivars echo (1987) and pelican (1988). a reduced root growth was found in both years which could be attributed mainly to the deposition of no2 and so2. effects on crop development most likely due to ozone were ... | 1992 | 15091971 |
| morphological responses of wheat to blue light. | blue light significantly increased tillering in wheat (triticum aestivum l.) plants grown at the same photosynthetic photon flux (ppf). plants were grown under two levels of blue light (400-500 nm) in a controlled environment with continuous irradiation. plants received either 50 micromoles m-2 s-1 of blue light or 2 micromoles m-2 s-1 blue light from filtered metal halide lamps at a total irradiance of 200 micromoles m-2 s-1 ppf (400-700 nm). plants tillered an average of 25% more under the hig ... | 1992 | 11537086 |
| characterization of two galactosidases extracted from wheat germ with a hydroalcoholic solvent. | alpha- and beta-d-galactosidases were characterized from a hydroalcoholic extract of wheat germ (triticum vulgare). kinetic constants (vmax and km) and the optimal phs for the hydrolysis of p-nitrophenyl galactopyranosides by both enzymes were determined. these enzymes presented a high stability in hydroalcoholic medium and were inhibited by iodoacetamide and sodium p-hydroxy-mercuribenzoate. | 1992 | 1576209 |
| two intron-containing pre-trnas(tyr) from triticum aestivum are efficiently processed and spliced in homologous cell-free extract. | two wheat pre-trnas(tyr) containing introns and flanks are accurately and efficiently spliced in homologous wheat germ s23 extract. the initiation and termination sites upon in vitro transcription in hela cell extract have been estimated for both pre-trnas. | 1992 | 1485489 |
| rapid separation of tyrosine-specific trna from white lupin. | during isolation of total ribonucleic acids from white lupin (lupinus albus) and their subsequent separation by 10% polyacrylamide gel electrophoresis, a fast migrating rna band is very well separated. the nucleotide sequence analysis of 76 nucleotide long sequence with many modified nucleosides was found to be identical with that of tyrosine specific trna of yellow lupin seeds (lupinus luteus) and wheat germ (triticum aestivum). also this trna(tyr) is identical with plant amber suppressor trna. ... | 1992 | 1441849 |
| absence of guar efficacy in complex spaghetti meals on postprandial glucose and c-peptide levels in healthy control and non-insulin-dependent diabetes mellitus subjects. | the effects of guar incorporated into a complex spaghetti meal on the glycaemic response in 11 healthy and 6 non-insulin dependent diabetic (niddm) subjects was studied. to this end, subjects consumed spaghetti made of either triticum aestivum or triticum durum wheat with or without 20 g% guar, as part of a complex meal containing 27% fat, 19% protein and 51% carbohydrate. in both the healthy as well as the niddm subjects the incremental integrated postprandial glucose and c-peptide responses af ... | 1992 | 1337059 |
| characterization and organization of gene families at the gli-1 loci of bread and durum wheats by restriction fragment analysis. | probes related to γ-gliadins and to the lmw subunits of glutenin were used to determine the complexity of the gli-1 loci, by rflp analysis of euploid and aneuploid lines of bread wheat cv chinese spring and durum wheat cv langdon. the two probes hybridised to separate sets of fragments derived from chromosomes 1 a, 1 b and 1d. the fragments related to the lmw subunit probe had a total copy number in hindiii digests of about 35 in chinese spring and 17 in langdon, with more fragments derived from ... | 1991 | 24202360 |
| nadh dehydrogenase: a new molecular marker for homoeology group 4 in triticeae. a map of the 4rs chromosome arm in rye. | structural gene loci encoding the monomeric isozymes nicotin adenin dinucleotide dehydrogenase (nadh dehydrogenase or ndh) have been located on the 4al, 4bα, and 4ds chromosome arms of triticum aestivum cv "chinese spring", on the 4rs chromosome arm of secale cereale cultivars "imperial", "king ii", "dakold," and "ailes," on the 4s(1) s/7s(1) chromosome of aegilops longissima, the 4e of elytrigia elongata, and the csu-a of aegilops umbellulata. all the results support the homoeologous relationsh ... | 1991 | 24202354 |
| effect of light and no(3) on wheat leaf phosphoenolpyruvate carboxylase activity: evidence for covalent modulation of the c(3) enzyme. | phosphoenolpyruvate carboxylase (pepcase) activity was studied in excised leaves of wheat (triticum aestivum l.) in the dark and in the light, in presence of either n-free (low-no(3) (-) leaves) or 40 millimolar kno(3) (high-no(3) (-) leaves) nutrient solutions. pepcase activity increased to 2.7-fold higher than that measured in dark-adapted tissue (control) during the first 60 minutes and continued to increase more slowly to 3.8-fold that of the control. this level was reached after 200 minutes ... | 1991 | 16668573 |
| expression of three rnase activities during natural and dark-induced senescence of wheat leaves. | we have monitored the activities of rnases wl(a), wl(b), and wl(c) (a blank, ta mckeon [1991] plant physiol 97: 1402-1408) during leaf senescence in wheat (triticum aestivum l. cv chinese spring). when seedlings were induced to senesce in darkness, protein loss from primary leaves began immediately. rnase wl(b) activity was unchanged for 2 days and then rose linearly, reaching a sixfold elevation in 7 days. rnase wl(c) activity declined for 2 days and then rose linearly, reaching a twofold eleva ... | 1991 | 16668564 |
| three rnases in senescent and nonsenescent wheat leaves : characterization by activity staining in sodium dodecyl sulfate-polyacrylamide gels. | we have described three rnases in wheat leaves (triticum aestivum l. cv chinese spring) and developed assays for measuring each rnase individually in crude leaf extracts. we initially used activity staining in sodium dodecyl sulfate-polyacrylamide gels to characterize rnases in extracts of primary and flag leaves. we thus identified acid rnase (ec 3.1.27.1, here designated rnase wl(a)), and two apparently novel enzymes, designated rnases wl(b) and wl(c). rnase wl(b) activity displays a distincti ... | 1991 | 16668563 |
| role of the root apoplasm for iron acquisition by wheat plants. | the role of the root apoplasm for iron acquisition was studied in wheat (triticum aestivum l. cv ares) grown in nutrient solution under controlled environmental conditions. to obtain different levels of fe in the root apoplasm, plants were supplied in the dark for 5 hours (preloading period) with various (59)fe-labeled fe compounds [fe(iii) hydroxide; microbial siderophores: fe rhodotorulic acid (ferda) and ferrioxamin (fedesferal(3)), and synthetic fe chelate (feeddha)], each at a concentration ... | 1991 | 16668547 |
| abrupt increase in the level of hydrogen peroxide in leaves of winter wheat is caused by cold treatment. | after cold treatment of seedlings of winter wheat (triticum aestivum l.), levels of hydrogen peroxide in the leaves were measured. the concentration of hydrogen peroxide increased to about three times the control level within a few minutes, and returned to the normal level in 15 to 20 minutes. the elevated level of hydrogen peroxide was found to be equivalent to 1.5 micromoles per gram fresh weight tissues of leaves. | 1991 | 16668520 |
| the k/na selectivity of a cation channel in the plasma membrane of root cells does not differ in salt-tolerant and salt-sensitive wheat species. | the characteristics of cation outward rectifier channels were studied in protoplasts from wheat root (triticum aestivum l. and triticum turgidum l.) cells using the patch clamp technique. the cation outward rectifier channels were voltage-dependent with a single channel conductance of 32 +/- 1 picosiemens in 100 millimolar kcl. whole-cell currents were dominated by the activity of the cation outward rectifiers. the time- and voltage-dependence of these currents was accounted for by the summed be ... | 1991 | 16668441 |
| the cytogenetic and molecular architecture of chromosome 1r--one of the most widely utilized sources of alien chromatin in wheat varieties. | chromosome 1r of rye (secale cereale) is one of the most intensively used sources of alien chromatin in bread wheat. it provides a source of valuable disease resistance genes and its widespread use has stimulated the development of genetic maps incorporating protein and dna markers. published data as well as new mapping data were combined into a consensus map by using common markers in the different mapping studies to orient the various data sets relative to each other. the consensus map provide ... | 1991 | 1769268 |
| patterns of actin filaments during cell shaping in developing mesophyll of wheat (triticum aestivum l.). | young leaves of wheat exhibit a smooth developmental gradient with meristematic cells at the base and highly differentiated cells at the tip. during differentiation, mesophyll cells attain a lobed outline resembling tube-shaped balloons with almost regularly spaced isthmi. microfilament patterns in developing wheat mesophyll cells were investigated using fluorescent-labeled phalloidin. various patterns were found, including delicate arrays of transversely oriented microfilaments in the cortex of ... | 1991 | 1724752 |
| restriction fragment length polymorphism (rflp) analysis in wheat. ii. linkage maps of the rflp sites in common wheat. | sixty-six f2 plants from the cross, triticum aestivum cv. chinese spring (abbrev. cs) x t. spelta var. duhamelianum (spelta), exhibiting the greatest number of rflps among eight common wheats, were analyzed for their rflp genotypes using genomic dna clones of cs as probes. in total, 204 rflp loci were identified and their linkage relationships established. by nulli-tetrasomic analyses, all linkage groups were assigned to one another of the 21 wheat chromosomes. in addition, the carrier chromosom ... | 1991 | 1685660 |
| influence of ozone on the stable carbon isotope composition, deltac, of leaves and grain of spring wheat (triticum aestivum l.). | the relative composition of stable carbon isotopes, delta(13)c, was determined in flag leaves and grain of spring wheat (triticum aestivum l. cv albis) grown in open-top field fumigation chambers and exposed to different o(3) levels during the growing season. the aim of the study was to establish exposure-response relationships for the radiation-weighted seasonal mean o(3) concentration and delta(13)c (relative deviation of the (13)c/(12)c ratio) values of the two plant parts. samples were colle ... | 1991 | 16668387 |
| modeling light and temperature effects on leaf emergence in wheat and barley. | phenological development affects canopy structure, radiation interception, and dry matter production; most crop simulation models therefore incorporate leaf emergence rate as a basic parameter. a recent study examined leaf emergence rate as a function of temperature and daylength among wheat (triticum aestivum l.) and barley (hordeum vulgare l.) cultivars. leaf emergence rate and phyllochron were modeled as functions of temperature alone, daylength alone, and the interaction between temperature ... | 2016 | 11537630 |
| a dna fragment mapped within the submicroscopic deletion of ph1, a chromosome pairing regulator gene in polyploid wheat. | bread wheat is an allohexaploid consisting of three genetically related (homoeologous) genomes. the homoeologous chromosomes are capable of pairing but strict homologous pairing is observed at metaphase 1. the diploid-like pairing is regulated predominantly by ph1, a gene mapped on long arm of chromosome 5b. we report direct evidence that a mutant of the gene (ph1b) arose from a submicroscopic deletion. a probe (xksus1-5) detects the same missing fragment in two independent mutants ph1b and ph1c ... | 1991 | 1936962 |
| general features of chromosome substitutions in triticum aestivum x t. timopheevii hybrids. | based on a c-banded chromosome analysis of triticum aestivum x t. timopheevii hybrid lines, we developed a classification of the a(t) and g genome chromosomes that agrees with the standard genetic nomenclature of t. aestivum chromosomes. transfer of genetic material from t. timopheevii to t. aestivum involved complete chromosomes, chromosome arms, or segments. frequencies of chromosome substitution were highest for homoeologous group 2 and lowest for group 4. moreover, b(g) substitutions were fr ... | 1991 | 24213071 |
| variability and uniformity of mitochondrial dna in populations of putative diploid ancestors of common wheat. | by using restriction endonuclease digestion patterns, the degree of intraspecific polymorphism of mitochondrial dna in four diploid species of wheat and aegilops, ae. speltoides, ae. longissima, ae. squarrosa, and triticum monococcum, was assessed. the outbreeding ae. speltoides was found to possess the highest degree of variability, the mean number of nucleotide substitutions among conspecific individuals being 0.027 substitutions per nucleotide site. a very low degree of mtdna variation was de ... | 1991 | 24213067 |
| short-term effects of nitrate on sucrose synthesis in wheat leaves. | experiments were carried out with fully expanded leaves from three-week-old seedlings of wheat (triticum aestivum l.) raised without no 3 (sup-) . nitrate was supplied to the leaves through the transpiration stream in the light. uptake of no 3 (sup-) was linear with no 3 (sup-) concentrations from 0 to 80 mm in the solution. net sucrose synthesis showed inverse relationships versus nitrate uptake, assimilation, and accumulation, with correlation coefficients close to 1. by contrast, no alteratio ... | 1991 | 24186279 |
| a triticum aestivum cdna clone encoding a low-molecular-weight heat shock protein. | | 1991 | 1863780 |