Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| developmental traits affecting low-temperature tolerance response in near-isogenic lines for the vernalization locus vrn-a1 in wheat (triticum aestivum l. em thell). | investigation of low-temperature (lt) tolerance in cereals has commonly led to the region of the vyn-a1 vernalization gene or its homologue in related genomes. two cultivars, one a non-hardy spring wheat and one a very cold-hardy winter wheat, whose growth habits are determined by the vrn-a1 (spring habit) and vrn-a1 (winter habit) alleles, were chosen to produce reciprocal near-isogenic lines (nils). these lines were then used to determine the relationship between rate of phenological developme ... | 0 | 12099532 |
| cloning of thioredoxin h reductase and characterization of the thioredoxin reductase-thioredoxin h system from wheat. | thioredoxins h are ubiquitous proteins reduced by nadph- thioredoxin reductase (ntr). they are able to reduce disulphides in target proteins. in monocots, thioredoxins h accumulate at high level in seeds and show a predominant localization in the nucleus of seed cells. these results suggest that the ntr-thioredoxin h system probably plays an important role in seed physiology. to date, the study of this system in monocots is limited by the lack of information about ntr. in the present study, we d ... | 2002 | 12106017 |
| in vitro cytotoxic effect of bread wheat gliadin on the lovo human adenocarcinoma cell line. | the pathogenesis of celiac disease is not completely understood but, although the initial step of the process is still unclear, an altered immune response seems to play a major role. previous studies of the biological properties of gliadin have highlighted its cytotoxic effects, and the aim of this study was to develop an in vitro technique to study them. the lovo (human colon adenocarcinoma) cell line grown in two-dimensional cultures was exposed to different concentrations of digested bread wh ... | 2002 | 12110270 |
| aluminium triggers malate-independent potassium release via ion channels from the root apex in wheat. | the regulatory mechanisms for the aluminium (al)-induced efflux of k(+) and malate from the root apex of al-resistant wheat ( triticum aestivum l. cv. atlas) were characterized. treatment with 20 mm tetraethylammonium (tea) chloride, a k(+)-channel inhibitor, blocked the al-induced k(+) efflux by 65%, but blocked the al-induced malate efflux only slightly. lanthanum (la(3+)) or ytterbium (yb(3+)) strongly inhibited the k(+) efflux, but slightly increased malate efflux. these lanthanides applied ... | 2002 | 12111222 |
| proteomic analysis of amphiphilic proteins of hexaploid wheat kernels. | wheat proteins and specially gluten proteins have been well studied and are closely associated with baking products. amphiphilic proteins (proteins that are soluble using nonionic detergent triton x-114 ) also play an important role in wheat quality. some of them, like puroindolines, are lipid binding proteins, and are strongly linked to dough foaming properties and to fine crumb texture. however many amphiphilic proteins are still unknown and both their physiological and technological functions ... | 2002 | 12112842 |
| cold-regulated cereal chloroplast late embryogenesis abundant-like proteins. molecular characterization and functional analyses. | cold acclimation and freezing tolerance are the result of complex interaction between low temperature, light, and photosystem ii (psii) excitation pressure. previous results have shown that expression of the wcs19 gene is correlated with psii excitation pressure measured in vivo as the relative reduction state of psii. using cdna library screening and data mining, we have identified three different groups of proteins, late embryogenesis abundant (lea) 3-l1, lea3-l2, and lea3-l3, sharing identiti ... | 2002 | 12114590 |
| effects of metals on seed germination, root elongation, and coleoptile and hypocotyl growth in triticum aestivum and cucumis sativus. | a simple, fast, and easy-to-perform method was carried out for the quantification of the inhibitory effects of metals on wheat and cucumber. the method uses seed germination, root elongation, and hypocotyl and coleoptile growth in these plants as parameters in the presence of varying concentrations of metals. metals selected for this study were hg, cd, co, cu, pb, and zn. although effective concentrations of these metals for a certain degree of inhibition were different, both plants had a reduce ... | 2002 | 12115046 |
| transcripts of vp-1 homeologues are misspliced in modern wheat and ancestral species. | the maize (zea mays) viviparous 1 (vp1) transcription factor has been shown previously to be a major regulator of seed development, simultaneously activating embryo maturation and repressing germination. hexaploid bread wheat (triticum aestivum) caryopses are characterized by relatively weak embryo dormancy and are susceptible to preharvest sprouting (phs), a phenomenon that is phenotypically similar to the maize vp1 mutation. analysis of vp-1 transcript structure in wheat embryos during grain d ... | 2002 | 12119408 |
| [morphology of wheat roots under low-phosphorus stress]. | the morphology of root systems of different wheat (triticum aestivum l.) genotypes under low-phosphorus stress were studied to determine the effects of external factors on components of root system and the early morphological indicators related to phosphorus efficiency. the number of root axes and the length of lateral root of p-deficient plant were significantly lower than those of p-sufficient plant. the length of root axis and root system, and the number of lateral roots were sharply increase ... | 2002 | 12132156 |
| [development of new pcr markers specific to a thinopyrum intermedium chromosome 2ai-2 and cloning of the st-specific sequences]. | to meet the need of selecting translocation lines, some new rapd markers for 2ai-2 chromosome of th. intermedium were identified in the paper. out of 320 rapd primers, 2 specific primers, opo05 and opm04, can amplify respectively a specific band with size of about 650 bp and 1400 bp in the bydv resistant materials containing the chromosome 2ai-2, including th. intermedium, wheat-th. intermedium partial amphipoild zhong 4 awnless, addition lines z1, z2 and z6, f1(z2/wan7107) and substitute line z ... | 2002 | 12143313 |
| [studies on fertility genes and its genetic characters in d2-type cms lines of common wheat]. | the kinds of fertility genes and its genetic characters for d2-type cms lines of common wheat were studied, the results showed: (1) for d2-type cms line, there was wide restoring sources and high digree of restoration in common wheat varieties (the restoring degree of 33.61% varieties exceeded 50%), and new cms lines were easily bred (25.21% varieties could maintain male sterility). these characters indicated that d2-type cms line was higher value in applied study, compared with t, k, v-type cms ... | 2002 | 12143315 |
| bioaccumulation of lanthanum and cerium and their effects on the growth of wheat (triticum aestivum l.) seedlings. | through short-term exposure (7-d exposure), long-term exposure (16-d exposure) and exposure-recovery (7-d exposure + 9-d recovery), the bioaccumulation and distribution of la and ce and their effects on growth of wheat seedlings were studied. addition of la (0.5-25 mg/l) and ce (0.5-25 mg/l) to the culture medium individually and in combination inhibited primary root elongation, reduced the dry weight of roots and shoots and the content of mineral elements (ca, mg, k, cu, zn). the damage increas ... | 2002 | 12143937 |
| a family 11 xylanase from penicillium funiculosum is strongly inhibited by three wheat xylanase inhibitors. | steady-state kinetic approaches were used to investigate the binding of a novel penicillium funiculosum xylanase, xync, with three known xylanase inhibitor proteins from wheat (triticum aestivum). the xylanase gene (xync) was cloned from a p. funiculosum genomic library and the deduced amino acid sequence of xync exhibited high sequence similarity with fungal family 11 xylanases. xync was overexpressed in p. funiculosum and the product (xync: m(r)=23.6 kda; pi=3.7) purified and shown to efficien ... | 2002 | 12147340 |
| detection of alien chromosomes from s-genome species in the addition/substitution lines of bread wheat and visualization of a-, b- and d-genomes by gish. | a modified approach based on the gish technique for detecting introgressed chromosomes/chromosome arms from closely related s-genome species to wheat genome and for visualization of a-, b- and d-genomes of triticum aestivum l. (genome aabbdd, 2n = 6x = 42) is presented. for detecting alien chromosomes we investigated two lines of bread wheat, one is an addition line with a pair of chromosome no. 4 short arms from aegilops searsii (4sss) and a wheat substitution line with a pair of chromosomes no ... | 2001 | 12152324 |
| development of a set of triticum aestivum-aegilops tauschii introgression lines. | new wheat introgression lines were obtained which contain different segments of individual chromosomes of aegilops tauschii in the triticum aestivum cv. 'chinese spring' background. the introgression lines were developed to examine various subsets of alleles from the wild grass in the genetic background of common wheat. as starting point substitution lines of 'chinese spring' in which single chromosomes of the d genome had been replaced by homologous chromosomes of a synthetic wheat were used. s ... | 2001 | 12152326 |
| identification of intergenomic translocations involving wheat, hordeum vulgare and hordeum chilense chromosomes by fish. | intergenomic translocations between wheat, hordeum chilense and hordeum vulgare have been obtained in tritordeum background. advanced lines from the crosses between three disomic chromosome addition lines for chromosome 2hv, 3hv, and 4hv of barley (hordeum vulgare) in triticum aestivum cv. chinese spring (cs) and hexaploid tritordeum (2n = 6x = 42, aabbhchhch) were analyzed. multicolor fish using both genomic dna from h. chilense and h. vulgare were used to establish the presence and numbers of ... | 2001 | 12152330 |
| a fertile amphiploid between durum wheat (triticum turgidum) and the x agroticum amphiploid (agropyron cristatum x t. tauschii). | agropyron (gaertn) is a genus of triticeae which includes the crested wheatgrass complex, i.e. a. cristatum (l.) as representative species containing the p genome. this species is an important source for increase the genetic variability of both durum and bread wheat. among the possible interesting features to be introgressed into wheat are resistance to wheat streak mosaic virus, rust diseases, and tolerance to drought, cold and moderate salinity. by crossing tetraploid wheat (triticum turgidum ... | 2001 | 12152332 |
| the triticeae genetic resources of central italy: collection, evaluation and conservation. | one hundred and six landraces belonging to 7 species of the triticeae tribe were collected in central italy by dbvba (perugia university), dibiaga (ancona university) and arssa (abruzzo region agricultural development agency) in different individual and joint missions. a few accessions were supplied by private and other public organisations. triticum dicoccum schubler is the most widespread species, followed by t. aestivum l., t. monococcum l., t. spelta l., t. turgidum var. durum desf., secale ... | 2001 | 12152333 |
| search for partial resistance to leaf rust in a collection of ancient spanish wheats. | a collection of 917 accessions of spanish durum and bread wheat was screened for resistance to leaf rust (puccinia triticina) under field conditions at three locations. resistance levels ranged from very low to very high, high susceptibility being most frequent. relative disease severity (referred to the most susceptible accession = 100%) was lower than 20% in about 6% of the accessions in each location. in the collection most of the lines (84%) displayed a susceptible infection type. a final se ... | 2001 | 12152334 |
| the effects of chromosomes 3a and 3b on resistance to fusarium head blight in tetraploid wheat. | fusarium head blight (fhb) caused by fusarium graminearum is one of the most destructive diseases of wheat in areas where the weather is warm and humid after heading. previous studies indicate that the level of resistance to fhb varies not only among wheat cultivars but also among some of their wild relatives. no accession, however, has yet been identified to be completely immune to fhb among the gramineae. it is known that durum wheat (triticum turgidum l. conv. durum) is consistently more susc ... | 2001 | 12152348 |
| effects of earthworm (eisenia fetida) and wheat (triticum aestivum) straw additions on selected properties of petroleum-contaminated soils. | current bioremediation techniques for petroleum-contaminated soils are designed to remove contaminants as quickly and efficiently as possible, but not necessarily with postremediation soil biological quality as a primary objective. to test a simple postbioremediation technique, we added earthworms (eisenia fetida) or wheat (triticum aestivum) straw to petroleum land-farm soil and measured biological quality of the soil as responses in plant growth, soil respiration, and oil and grease (o&g) and ... | 2002 | 12152766 |
| toxicity of methyl tert-butyl ether to plants (avena sativa, zea mays, triticum aestivum, and lactuca sativa). | influence of methyl tert-butyl ether (mtbe) on the germination of seeds and growth of seedling plants were studied in laboratory experiments. test plants were wild oats (avena sativa), sweet corn (zea mays), wheat (triticum aestivum), and lettuce (lactuca sativa). seed germination, shoot growth, and root growth of plants exposed to different concentrations of mtbe in a moist soil were examined. seed germination and seedling growth in mtbe-contaminated soil were markedly reduced in all test plant ... | 2002 | 12152769 |
| allergologic exploration of germins and germin-like proteins, a new class of plant allergens. | germins and the related germin-like proteins (glps) are glycoproteins expressed in many plants in response to biotic and abiotic stress. to test the potential impact of germins and glps, recombinant germin from triticum aestivum (tgermin) and glps from arabidopsis thaliana (tglp), both produced in transformed tobacco plants, were used. | 2002 | 12169176 |
| differential stress responses of early salt-stress responding genes in common wheat. | four early salt-stress responding genes (wesr1-4) in common wheat (triticum aestivum l.) were analyzed for their temporal accumulation of mrna during salt stress, osmotic stress and abscisic acid (aba) treatment. all genes showed transient stimulation by 0.15 m nacl treatment. wesr1 and wesr2 were induced by both osmotic stress and exogenous aba treatment. wesr3 responded to exogenous aba, but not to osmotic stress. wesr4 did not show significant response to either osmotic stress or exogenous ab ... | 2002 | 12169305 |
| assessment of plant uptake of radioactive nickel from soils. | as a result of isotopic dilution, the availability to plants of radioisotopes introduced into the soil solution should be directly related to the size of the isotopically exchangeable pool (e(t))-value). this work was undertaken to test this hypothesis for the radionuclide 63ni. the demonstration was based on pot experiments conducted with seven soils representing a large range of ni content (from 9.9 mg kg(-1) to 862.6 mg kg(-1)) which were mixed with a 63nicl2 solution (100 kbq kg(-1)). three ... | 2002 | 12171471 |
| regulation of sucrose and starch synthesis in wheat (triticum aestivum l.) leaves: role of fructose 2,6-bisphosphate. | fructose 2,6-bisphosphate (f26bp) is a competitive inhibitor of the cytosolic fructose 1,6-bisphosphatase (cytfbpase, ec 3.1.3.11). in spinach (spinacia oleracea l.) leaves it is a significant component of the complex regulatory network that co-ordinates rates of photosynthesis, sucrose synthesis and starch synthesis. however the role of f26bp has only been studied in plants that predominantly store starch in their leaves and its role in other species is not clear. this paper examines the signif ... | 2002 | 12172849 |
| simulated effects of crop rotations and residue management on wind erosion in wuchuan, west-central inner mongolia, china. | for decades, wind erosion has triggered dust and sand storms, buffeting beijing and areas of northwestern china to the point of being hazardous to human health while rapidly eroding crop and livestock productivity. the epic (environmental policy integrated climate) field-scale simulation model was used to assess long-term effects of improved crop rotations and crop residue management practices on wind erosion in wuchuan county in inner mongolia. simulation results indicate that preserving crop s ... | 2002 | 12175042 |
| assessment of genomic diversity among wheat genotypes as determined by simple sequence repeats. | simple sequence repeats (ssrs) have been used to examine the genomic diversity of wheat (triticum aestivum l.) germplasm. thirteen wheat genotypes of diverse origin were analyzed with 43 selected ssrs to provide uniform and maximum genome coverage. a total of 156 allelic variants were detected at 43 ssr loci, ranging from two to eight per locus with an average of 3.6. the polymorphic information content (pic) values of the loci ranged from 0.10 (xgwm264) to 0.89 (xgwm471 and xgwm577). genetic si ... | 2002 | 12175067 |
| genomic targeting and high-resolution mapping of the domestication gene q in wheat. | the q locus is largely responsible for the domestication of bread wheat. q confers the free-threshing character of the spike and influences other important agronomic traits. using chromosome deletion lines, q was placed on the physical map within a submicroscopic segment of the long arm of chromosome 5a. we targeted markers to the segment by comparative mapping of anonymous rflp clones, aflp, and mrna differential display analysis of deletion lines 5al-7 and -23, which have deletion breakpoints ... | 2002 | 12175074 |
| barley cbf3 gene identification, expression pattern, and map location. | although cold and drought adaptation in cereals and other plants involve the induction of a large number of genes, inheritance studies in triticeae (wheat [triticum aestivum], barley [hordeum vulgare], and rye [secale cereale]) have revealed only a few major loci for frost or drought tolerance that are consistent across multiple genetic backgrounds and environments. one might imagine that these loci could encode highly conserved regulatory factors that have global effects on gene expression; the ... | 0 | 12177491 |
| [identification of blue grained wheat and its irradiation-mutated offsprings by genomic in situ hybridization (gish)]. | transferring useful chromosome(s), chromosomal fragment(s) or genes from related species into common wheat (triticum aestivum l.) is an effective method for improving wheat cultivars, and dna:dna in situ hybridization has been proven to be an effective method for directly demonstrating alien chromosome number and distribution in plant. in this study, genomic in situ hybridization (gish) was used to identify the chromosomal constitutions of the blue-grained wheat blue-58 originated from distant h ... | 2002 | 12182082 |
| [factors affecting agrobacterium tumefaciens-mediated transformation of wheat (triticum aestivum l.)]. | immature embryos and embryo-derived calli from two cultivars of winter wheat (triticum aestivum l.), bau146 and bau170, were transformed with three strains of agrobacterium tumefaciens, agl-1, eha105 and lba4404 harboring expression vector p3301 or pbtaab. both vectors contained bar gene and p3301 contained also gus gene with an intron. the highest explant survival rate and transformation efficiency was obtained when the bacterial cell density was od600 1.0 with 1 h of infection incubation. high ... | 2002 | 12182083 |
| molecular cloning, characterization and mapping of a rhodanese like gene in wheat. | to isolate genes related to resistance to erysiphe graminis (blumeria graminis) dc. f. sp. tritici in wheat (triticum aestivum l.), differential display analysis was conducted for mrna extracted from seedlings of a wheat-haynaldia villosa 6vs/6al translocation line 92r137 that contains a powdery mildew resistance gene pm21. a full-length cdna sequence named tatst (triticum aestivum thiosulfate sulfurtransferase) homologous to the thiosulfate sulfurtransferase (rhodanese) in datisca glomerata was ... | 2002 | 12182084 |
| a mycorrhiza-responsive protein in wheat roots. | a small protein, designated myk15, was found to be strongly induced in wheat ( triticum aestivum) roots colonized by the arbuscular mycorrhizal fungus glomus intraradices. this protein, which is most abundant in root fractions characterized by strong mycorrhizal colonization, has been characterized using two-dimensional polyacrylamide gel electrophoresis and microsequencing. it has an apparent molecular mass of 15 kda and an isoelectric point of 4.5. the n-terminal sequence has high similarity t ... | 2002 | 12189477 |
| [screening for resistance gene candidate from a genomic tac library of triticum aestivum-haynaldia villosa translocation line 6vs/6al by pooled pcr]. | a pair of degenerate primers were designed based on nbs (nucleotide binding site, nbs) domain of resistance(r) gene and used to perform pcr with cdna from the translocation line 6vs/6al of triticum aestivum-haynaldia villosa. a clone (n7) characterized with nbs was obtained by sequencing analysis. two specific primers were designed from the n7 sequence and used to screen a genomic tac (transformation-competent artificial chromosome, tac) library of 6vs/6al consisting of ca. 2 x 10(6) clones. the ... | 2002 | 12192864 |
| relationships between digestibilities of food components and characteristics of wheats (triticum aestivum) introduced as the only cereal source in a broiler chicken diet. | 1. the aim of the experiment was to establish relationships between chemical or physical characteristics of wheats (triticum aestivum) and digestibilities of food components in broiler chickens fed on wheat-based diets. twenty-two wheat samples, each differing by their cultivar origin, were included at 550 g/kg in diets offered to male ross broiler chicks. the other main ingredients were soya bean meal (340 g/kg) and rapeseed oil (68.5 g/kg). diets were given as pellets. 2. in vitro viscosities ... | 2002 | 12195800 |
| mapping quantitative trait loci for plant height in wheat (triticum aestivum l.) using a f2:3 population. | to detect quantitative trait loci (qtls) controlling plant height, the plant height of 240 f2:3 lines derived from the cross of a dwarf wheat line nd3338 with a tall line f390, was assessed in field trials at two locations with three replications in 2000 and 2001. microsatellite markers were used to construct a framework linkage map containing 215 loci with 21 linkage groups, and covering the whole genome about 3600cm. with the method of interval mapping, seven putative qtls affecting plant heig ... | 2002 | 12200862 |
| transport interactions between cadmium and zinc in roots of bread and durum wheat seedlings. | field studies have shown that the addition of zn to cd-containing soils can help reduce accumulation of cd in crop plants. to understand the mechanisms involved, this study used 109cd and 65zn to examine the transport interactions of zn and cd at the root cell plasma membrane of bread wheat (triticum aestivum l.) and durum wheat (triticum turgidum l. var. durum). results showed that cd2+ uptake was inhibited by zn2+ and zn2+ uptake was inhibited by cd2+. concentration-dependent uptake of both cd ... | 2002 | 12207664 |
| flow cytometric analyses of intraplant nuclear dna content variation induced by sticky chromosomes. | in several plant species, sticky chromosomes are a consequence of genetic mutations or environmental effects on mitosis and meiosis. sticky chromosomes result in an unequal distribution of genetic material in daughter cells. this unequal distribution is hypothesized to result in an increase in the coefficient of variation (cv) of the g1 peak of dividing cells. | 2002 | 12210609 |
| combinatorial labelling of dna probes enables multicolour fluorescence in situ hybridisation in plants. | this paper demonstrates a simple but effective use of combinatorial probes to label plant chromosomes by multicolour fluorescence in situ hybridisation (fish). three different dna probes were labelled with only two different fluorophores, hybridised to somatic metaphase chromosomes of secale cereale and triticum aestivum, simultaneously visualised, and unequivocally distinguished in a single fish experiment. combinatorial labelling can augment karyotypical investigations, physical mapping of chr ... | 2002 | 12219843 |
| [effect of clipping at seedling stage on growth and yield of spring wheat]. | the compensation for spring wheat (triticum aestivum) under simulated herbivory stress by clipping was examined in a semi-arid region of gansu province in 1996. the results showed that clipping at seedling stage reduced spring wheat growth under two irrigation conditions. the yield of spring wheat generally under-compensated the clipping effect. heavy clipping (cutting all leaves above the ground, t0, t1) resulted in a more serious reduction in yield, compared with light clipping cutting half of ... | 2002 | 12222043 |
| purification and characterization of a [beta]-d-xylosidase and an endo-xylanase from wheat flour. | a [beta]-d-xylosidase and an endo-xylanase were purified from european wheat (triticum aestivum) flour. the [beta]-d-xylosidase had a molecular weight of approximately 64,000 and an isoelectric point of 5.5. it hydrolyzed p-nitrophenyl-[beta]-d-xylopyranoside and xylo-oligosaccharides and released d-xylose units from wheat arabinoxylan and oat spelts xylan. an endo-xylanase with a molecular weight of approximately 55,000 was also obtained and it consisted of a number of isoforms with isoelectric ... | 1997 | 12223612 |
| al partitioning patterns and root growth as related to al sensitivity and al tolerance in wheat. | studies of al partitioning and accumulation and of the effect of al on the growth of intact wheat (triticum aestivum l.) roots of cultivars that show differential al sensitivity were conducted. the effects of various al concentrations on root growth and al accumulation in the tissue were followed for 24 h. at low external al concentrations, al accumulation in the root tips was low and root growth was either unaffected or stimulated. calculations based on regression analysis of growth and al accu ... | 1997 | 12223623 |
| osmotic stress suppresses cell wall stiffening and the increase in cell wall-bound ferulic and diferulic acids in wheat coleoptiles. | the relationship between the mechanical properties of cell walls and the levels of wall-bound ferulic (fa) and diferulic (dfa) acids was investigated in wheat (triticum aestivum l.) coleoptiles grown under osmotic stress (60 mm polyethylene glycol [peg] 4000) conditions. the cell walls of stressed coleoptiles remained extensible compared with those of the unstressed ones. the contents of wall-bound fa and dfa increased under unstressed conditions, but the increase was substantially reduced by os ... | 1997 | 12223657 |
| direct evaluation of the ca2+-displacement hypothesis for al toxicity. | one explanation for al toxicity in plants suggests that al displaces ca2+ from critical sites in the apoplasm. we evaluated the ca2+-displacement hypothesis directly using near-isogenic lines of wheat (triticum aestivum l.) that differ in al tolerance at a single locus. we measured both the growth and total accumulation (apoplasmic plus symplasmic) of 45ca and al into roots that had been exposed to al alone or to al with other cations. root growth in the al-sensitive line was found to be severel ... | 1997 | 12223678 |
| al-induced, 51-kilodalton, membrane-bound proteins are associated with resistance to al in a segregating population of wheat. | incorporation of 35s into protein is reduced by exposure to al in wheat (triticum aestivum), but the effects are genotype-specific. exposure to 10 to 75 [mu]m al had little effect on 35s incorporation into total protein, nuclear and mitochondrial protein, microsomal protein, and cytosolic protein in the al-resistant cultivar pt741. in contrast, 10 [mu]m al reduced incorporation by 21 to 38% in the al-sensitive cultivar katepwa, with effects becoming more pronounced (31-62%) as concentrations of ... | 1997 | 12223709 |
| an electron paramagnetic resonance spin-probe study of membrane-permeability changes with seed aging. | we developed an electron paramagnetic resonance spin-probe technique to study changes in the barrier properties of plasma membranes in wheat (triticum aestivum l.) seeds during aging under dry storage. the estimation of these barrier properties was based on the differential permeability of membranes for the stable free radical 4-oxo-2,2,6,6-tetramethyl-1-piperidinyloxy and the broadening agent ferricyanide. the line-height ratio between the water and lipid components in the electron paramagnetic ... | 1997 | 12223711 |
| importance of the chiral centers of jasmonic acid in the responses of plants (activities and antagonism between natural and synthetic analogs). | the importance of the two chiral centers at c-3 and c-7 in the molecular structure of jasmonic acid in plant responses was investigated. we separated methyl jasmonate (meja) into (3r)- and (3s)-isomers with a fixed stereochemistry at c-3, but epimerization at c-7 is possible. the four isomers of the nonepimerizable analog 7-methyl meja were synthesized. these six esters and their corresponding acids were tested in three bioassays: (a) senescence in sunflower (helianthus annuus) cotyledons; (b) p ... | 1997 | 12223716 |
| differential induction of lipoxygenase isoforms in wheat upon treatment with rust fungus elicitor, chitin oligosaccharides, chitosan, and methyl jasmonate. | a glycopeptide elicitor prepared from germ tubes of the rust fungus puccinia graminis pers. f. sp. tritici erikss. & henn (pgt), as well as chitin oligosaccharides, chitosan, and methyl jasmonate (mj) stimulated lipoxygenase (lox) activity (e.c. 1.13.11.12) in wheat (triticum aestivum) leaves. immunoblot analysis using anti-lox antibodies revealed the induction of 92- and 103-kd lox species after pgt elicitor treatment. in contrast, mj treatment led to a significant increase of a 100-kd lox spec ... | 1997 | 12223735 |
| characterization of water channels in wheat root membrane vesicles. | the functional significance of water channels in wheat (triticum aestivum l.) root membranes was assessed using light scattering to measure vesicle shrinking in response to osmotic gradients rapidly imposed in a stopped flow apparatus. vesicles were obtained from both a plasma membrane fraction and a plasma membrane-depleted endomembrane fraction including tonoplast vesicles. osmotic water permeability (pos) in the endomembrane fraction was high (pos= 86.0 [mu]m s-1) with a low activation energy ... | 1997 | 12223824 |
| possible involvement of al-induced electrical signals in al tolerance in wheat. | the relationship between al-induced depolarization of root-cell transmembrane electrical potentials (em) and al tolerance in wheat (triticum aestivum l.) was investigated. al exposure induced depolarizations of em in the al-tolerant wheat cultivars atlas and et3, but not in the al-sensitive wheat cultivars scout and es3. the depolarizations of em occured in root cap cells and as far back as 10 mm from the root tip. the depolarization was specific to al3+; no depolarization was observed when root ... | 1997 | 12223834 |
| sorption of aluminum to plasma membrane vesicles isolated from roots of scout 66 and atlas 66 cultivars of wheat. | to further elucidate the mechanisms of differential genotypic tolerance to al, plasma membrane (pm) vesicles were isolated from whole roots, root tips, and tipless roots of al3+-sensitive and al3+-tolerant cultivars (cv) of wheat (triticum aestivum l. cv scout 66 and cv atlas 66, respectively). vesicles from cv scout root tips sorbed more al than vesicles prepared from any other source. the intrinsic surface-charge density of vesicles isolated from cv scout was 26% more negative than vesicles fr ... | 1997 | 12223862 |
| so42- deprivation has an early effect on the content of ribulose-1,5-bisphosphate carboxylase/oxygenase and photosynthesis in young leaves of wheat. | wheat (triticum aestivum cv chinese spring) supplied with 0.45 mm so42- for 14 d with relative growth rates (rgr) of 0.22 to 0.24 d-1 was deprived of s for 7 to 8 d. there was no significant effect on rgr or leaf development (leaf 2 length was constant; leaf 3 expanded for 2-4 d; leaf 4 emerged and elongated throughout the experiment) during the s deprivation. in controls the net assimilation rate (a) closely reflected leaf ontogeny. s deprivation affected a in all leaves, particularly leaf 4, i ... | 1997 | 12223869 |
| constitutively elevated levels of putrescine and putrescine-generating enzymes correlated with oxidant stress resistance in conyza bonariensis and wheat. | oxidant stress resistance in conyza bonariensis and wheat (triticum aestivum) has been correlated with high levels of antioxidant enzyme activities. additionally, external oxidant stresses can increase a plant's levels of the enzymes of polyamine biosynthesis and polyamines, especially putrescine. we investigated the constitutive relationships between putrescine, putrescine-generating enzymes, and oxidant stress resistance in wheat and c. bonariensis. putrescine was constitutively elevated (2.5- ... | 1997 | 12223875 |
| photosystem ii excitation pressure and development of resistance to photoinhibition (ii. adjustment of photosynthetic capacity in winter wheat and winter rye). | winter wheat (triticum aestivum l. cv monopol), spring wheat (triticum aestivum l. cv katepwa), and winter rye (secale cereale l. cv musketeer) grown at 5[deg]c and moderate irradiance (250 [mu]mol m-2 s-1) (5/250) exhibit an increased tolerance to photoinhibition at low temperature in comparison to plants grown at 20[deg]c and 250 [mu]mol m-2 s-1 (20/250). however, 5/250 plants exhibited a higher photosystem ii (psii) excitation pressure (0.32-0.63) than 20/250 plants (0.18-0.21), measured as 1 ... | 1996 | 12226171 |
| aluminum interactions with voltage-dependent calcium transport in plasma membrane vesicles isolated from roots of aluminum-sensitive and -resistant wheat cultivars. | the role of al interactions with root-cell plasma membrane (pm) ca2+ channels in al toxicity and resistance was studied. the experimental approach involved the imposition of a transmembrane electrical potential (via k+ diffusion) in right-side-out pm vesicles derived from roots of two wheat (triticum aestivum l.) cultivars (al-sensitive scout 66 and al-resistant atlas 66). we previously used this technique to characterize a voltage-dependent ca2+ channel in the wheat root pm (j.w. huang, d.l. gr ... | 1996 | 12226204 |
| peroxygenase-catalyzed fatty acid epoxidation in cereal seeds (sequential oxidation of linoleic acid into 9(s),12(s),13(s)-trihydroxy-10(e)-octadecenoic acid). | peroxygenase-catalyzed epoxidation of oleic acid in preparations of cereal seeds was investigated. the 105,000g particle fraction of oat (avena sativa) seed homogenate showed high peroxygenase activity, i.e. 3034 [plus or minus] 288 and 2441 [plus or minus] 168 nmol (10 min)-1 mg-1 protein in two cultivars, whereas the corresponding fraction obtained from barley (hordeum vulgare and hordeum distichum), rye (secale cereale), and wheat (triticum aestivum) showed only weak activity, i.e. 13 to 138 ... | 1996 | 12226220 |
| subcellular visualization of gene transcripts encoding key proteins of the chlorophyll accumulation process in developing chloroplasts. | the coordination of the synthesis of chlorophyll (chl) and light-harvesting chl proteins was determined by observing the sequence of appearance of the specific mrnas for the nuclear genes chlh, por, and lhcb1*2 (ab180). chlh encodes a magnesium protoporphyrin chelatase subunit that is involved in the first committed step in chl biosynthesis; por encodes protochlorophyllide oxidoreductase, which catalyzes the penultimate and only light-dependent step in chl biosynthesis; and lhcb1*2 encodes light ... | 1996 | 12226243 |
| induction of male sterility in wheat by meiotic-stage water deficit is preceded by a decline in invertase activity and changes in carbohydrate metabolism in anthers. | water deficit during meiosis in pollen mother cells of wheat (triticum aestivum l.) induces male sterility, which can reduce grain set by 40 to 50%. in plants stressed during meiosis and then rewatered, division of pollen mother cells proceeds normally but subsequent pollen development is arrested 3 or 4 d later. an inhibition of starch accumulation within the pollen grain suggested that an alteration in carbohydrate metabolism or assimilate supply may be involved in pollen abortion. we measured ... | 1996 | 12226280 |
| in vivo and in vitro phosphorylation of the phosphoenolpyruvate carboxylase from wheat seeds during germination. | phosphoenolpyruvate carboxylase (pepc) activity was detected in the aleurone endosperm of wheat (triticum aestivum cv chinese spring) seeds, and specific anti-sorghum c4 pepc polyclonal anti-bodies cross-reacted with 103- and 100-kd polypeptides present in dry seeds and seeds that had imbibed; in addition, a new, 108-kd polypeptide was detected 6 h after imbibition. the use of specific anti-phosphorylation-site immunoglobulin g (aps-igg) identified the presence of a phosphorylation motif equival ... | 1996 | 12226309 |
| germin gene expression is induced in wheat leaves by powdery mildew infection. | germin gene expression is induced in wheat (triticum aestivum l.) leaves by powdery mildew (erysiphe graminis f. sp. tritici) infection. germin is a protein marker for early cereal development and is an oxalate oxidase, an enzyme that catalyzes the conversion of oxalate to co2 and h2o2. the induction of germin gene expression by powdery mildew infection is consistent with the importance of h2o2 to plant defense and identifies a mechanism for the elevation of h2o2 levels in wheat leaves. germin m ... | 1996 | 12226325 |
| evidence for the contribution of the mehler-peroxidase reaction in dissipating excess electrons in drought-stressed wheat. | gross o2 evolution and uptake by attached, drought-stressed leaves of wheat (triticum aestivum) were measured using a 16o2/ 18o2 isotope technique and mass spectrometry. the activity of photosystem ii, determined from the rate of 16o2 evolution, is only slightly affected under drought conditions. during drought stress, net co2 uptake decreases due to stomatal closure, whereas the uptake of 18o2 is stimulated. the main o2-consuming reactions in the light are the mehler-peroxidase (mp) reaction an ... | 1996 | 12226390 |
| multiple aluminum-resistance mechanisms in wheat (roles of root apical phosphate and malate exudation). | although it is well known that aluminum (al) resistance in wheat (triticum aestivum) is multigenic, physiological evidence for multiple mechanisms of al resistance has not yet been documented. the role of root apical phosphate and malate exudation in al resistance was investigated in two wheat cultivars (al-resistant atlas and al-sensitive scout) and two near-isogenic lines (al-resistant et3 and al-sensitive es3). in atlas al resistance is multigenic, whereas in et3 resistance is conditioned by ... | 1996 | 12226413 |
| characterization of the endoproteases appearing during wheat grain development. | the pattern of endoproteolytic activities occurring during wheat (triticum aestivum, cultivar chinese spring) grain development was investigated. total endoprotease activity, assayed in solution with azocasein as a substrate, increased during the early stages of grain development to reach a maximum at 15 d postanthesis that was maintained until the grain was mature. endoprotease activity was also assayed in gradient polyacrylamide gels co-polymerized with gelatin. the increase in endoproteolytic ... | 1996 | 12226440 |
| accumulation of al in root mucilage of an al-resistant and an al-sensitive cultivar of wheat. | to estimate rates of al accumulation within the symplasm, all apoplastic pools of al need to be eliminated or accounted for. we have developed a revised kinetic protocol that allows us to estimate the contribution of mucilage-bound al to total, nonexchangeable al, and to eliminate the mucilage as an apoplastic pool of al. by comparing the al content of excised root tips (2 cm) of wheat (triticum aestivum l.) with and without the removal of the mucilage (using a 10-min wash in 1 m nh4cl), we foun ... | 1996 | 12226458 |
| the physiological relevance of na+-coupled k+-transport. | plant roots utilize at least two distinct pathways with high and low affinities to accumulate k+. the system for high-affinity k+ uptake, which takes place against the electrochemical k+ gradient, requires direct energization. energization of k+ uptake via na+ coupling has been observed in algae and was recently proposed as a mechanism for k+ uptake in wheat (triticum aestivum l.). to investigate whether na+ coupling has general physiological relevance in energizing k+ transport, we screened a n ... | 1996 | 12226467 |
| tandemly duplicated safener-induced glutathione s-transferase genes from triticum tauschii contribute to genome- and organ-specific expression in hexaploid wheat. | glutathione s-transferase (gst) gene expression was examined in several triticum species, differing in genome constitution and ploidy level, to determine genome contribution to gst expression in cultivated, hexaploid bread wheat (triticum aestivum). two tandemly duplicated tau class gst genes (ttgstu1 and ttgstu2) were isolated from a single bacterial artificial chromosome clone in a library constructed from the diploid wheat and d genome progenitor to cultivated wheat, triticum tauschii. the ge ... | 2002 | 12226515 |
| short-term boron deprivation inhibits endocytosis of cell wall pectins in meristematic cells of maize and wheat root apices. | by using immunofluorescence microscopy, we observed rapidly altered distribution patterns of cell wall pectins in meristematic cells of maize (zea mays) and wheat (triticum aestivum) root apices. this response was shown for homogalacturonan pectins characterized by a low level (up to 40%) of methylesterification and for rhamnogalacturonan ii pectins cross-linked by a borate diol diester. under boron deprivation, abundance of these pectins rapidly increased in cell walls, whereas their internaliz ... | 2002 | 12226520 |
| arabinoxylan biosynthesis in wheat. characterization of arabinosyltransferase activity in golgi membranes. | arabinoxylan arabinosyltransferase (ax-arat) activity was investigated using microsomes and golgi vesicles isolated from wheat (triticum aestivum) seedlings. incubation of microsomes with udp-[(14)c]-beta-l-arabinopyranose resulted in incorporation of radioactivity into two different products, although most of the radioactivity was present in xylose (xyl), indicating a high degree of udp-arabinose (ara) epimerization. in isolated golgi vesicles, the epimerization was negligible, and incubation w ... | 2002 | 12226522 |
| significant changes in cell and chloroplast development in young wheat leaves (triticum aestivum cv hereward) grown in elevated co2. | cell and chloroplast development were characterized in young triticum aestivum cv hereward leaves grown at ambient (350 [mu]l l-1) or at elevated (650 [mu]l l-1) co2. in elevated co2, cell and chloroplast expansion was accelerated by 10 and 25%, respectively, in the first leaf of 7-d-old wheat plants without disruption to the leaf developmental pattern. elevated co2 did not affect the number of chloroplasts in relation to mesophyll cell size or the linear relationship between chloroplast number ... | 1995 | 12228342 |
| aluminum-induced genes (induction by toxic metals, low calcium, and wounding and pattern of expression in root tips). | we have investigated the response of four al-induced genes (wali1, -3, -4, and -5) from wheat (triticum aestivum l.) to other stresses. the relative transcript levels of wali1 (encoding a plant metallothionein-like protein), wali3 and wali5 (putative bowman-birk proteinase inhibitors), and wali4 (phenylalanine ammonialyase) increased in root tips of wheat after 2-d treatments with toxic levels of all other metals tested (cd, fe, zn, cu, ga, in, and la). the expression levels of wali1, -3, -4, an ... | 1995 | 12228362 |
| in vivo regulation of wheat-leaf phosphoenolpyruvate carboxylase by reversible phosphorylation. | regulation of c3 phosphoenolpyruvate carboxylase (pepc) and its protein-serine/threonine kinase (pepc-pk) was studied in wheat (triticum aestivum) leaves that were excised from low-n-grown seedlings and subsequently illuminated and/or supplied with 40 mm kno3. the apparent phosphorylation status of pepc was assessed by its sensitivity to l-malate inhibition at suboptimal assay conditions, and the activity state of pepc-pk was determined by the in vitro 32p labeling of purified maize dephospho-pe ... | 1995 | 12228402 |
| mitochondria increase three-fold and mitochondrial proteins and lipid change dramatically in postmeristematic cells in young wheat leaves grown in elevated co2. | a dramatic stimulation in mitochondrial biogenesis during the very early stages of leaf development was observed in young wheat plants (triticum aestivum cv hereward) grown in elevated co2 (650 [mu]l l-1). an almost 3-fold increase in the number of mitochondria was observed in the very young leaf cells at the base of the first leaf of a 7-d-old wheat plant. in the same cells large increases in the accumulation of a mitochondrial chaperonin protein and the mitochondrial 2-oxoglutarate dehydrogena ... | 1995 | 12228485 |
| increased accumulation of carbohydrates and decreased photosynthetic gene transcript levels in wheat grown at an elevated co2 concentration in the field. | repression of photosynthetic genes by increased soluble carbohydrate concentrations may explain acclimation of photosynthesis to elevated co2 concentration. this hypothesis was examined in a field crop of spring wheat (triticum aestivum l.) grown at both ambient (approximately 360 [mu]mol mol-1) and elevated (550 [mu]mol mol-1) atmospheric co2 concentrations using free-air co2 enrichment at maricopa, arizona. the correspondence of steady-state levels of mrna transcripts (coding for the 83-kd pho ... | 1995 | 12228521 |
| the wheat abscisic acid-responsive protein kinase mrna, pkaba1, is up-regulated by dehydration, cold temperature, and osmotic stress. | the effects of dehydration, cold-temperature treatment, and osmotic and salt stress on the expression of an abscisic acid-responsive protein kinase mrna (pkaba1) were determined in wheat (triticum aestivum l.) seedlings. the pkaba1 transcript was detectable at basal levels in tissues of nonstressed plants and accumulated to higher levels in shoot, scutellar, and root tissues of stressed plants. pkaba1 transcript accumulated rapidly within 2 h following dehydration and within 24 h following other ... | 1995 | 12228537 |
| differential solute regulation in leaf blades of various ages in salt-sensitive wheat and a salt-tolerant wheat x lophopyrum elongatum (host) a. love amphiploid. | leaf blades of different ages from a salt-tolerant wheat x lophopyrum elongatum (host) a. love (syn. agropyron elongatum host) amphiploid and its salt-sensitive wheat parent (triticum aestivum l.cv chinese spring) were compared for their ionic relations, organic solute accumulation, and sap osmotic potential ([pi]sap). the plants were grown for 18 d in nonsaline (1.25 mm na+) and salinized (200 mm nacl) nutrient solutions. the response of leaf blades to nacl salinity depended greatly on their ag ... | 1995 | 12228575 |
| amelioration of ozone-induced oxidative damage in wheat plants grown under high carbon dioxide (role of antioxidant enzymes). | o3-induced changes in growth, oxidative damage to protein, and specific activities of certain antioxidant enzymes were investigated in wheat plants (triticum aestivum l. cv roblin) grown under ambient or high co2. high co2 enhanced shoot biomass of wheat plants, whereas o3 exposure decreased shoot biomass. the shoot biomass was relatively unaffected in plants grown under a combination of high co2 and o3. o3 exposure under ambient co2 decreased photosynthetic pigments, soluble proteins, and ribul ... | 1995 | 12228603 |
| sucrose release into the endosperm cavity of wheat grains apparently occurs by facilitated diffusion across the nucellar cell membranes. | nutrients required for the growth of the embryo and endosperm of developing wheat (triticum aestivum l.) grains are released into the endosperm cavity from the maternal tissues across the nucellar cell plasma membranes. we followed the uptake and efflux of sugars into and out of the nucellus by slicing grains longitudinally through the endosperm cavity to expose the nucellar surface to experimental solutions. sucrose uptake and efflux are passive processes. neither was sensitive to metabolic inh ... | 1995 | 12228614 |
| sucrose concentration gradients along the post-phloem transport pathway in the maternal tissues of developing wheat grains. | sucrose concentrations were measured in serial frozen sections of the post-phloem transport pathway in developing wheat (triticum aestivum l.) grains. in normally importing grains, there was an approximately linear concentration gradient along the pathway, with a difference between the ends of the pathway of about 180 mm. this indicates an unusually low resistance for cell-to-cell transport, due perhaps to the large size-exclusion limit for the pathway. however, the existence of concentration gr ... | 1995 | 12228615 |
| cold hardening of spring and winter wheat and rape results in differential effects on growth, carbon metabolism, and carbohydrate content. | the effect of long-term (months) exposure to low temperature (5[deg]c) on growth, photosynthesis, and carbon metabolism was studied in spring and winter cultivars of wheat (triticum aestivum) and rape (brassica napus). cold-grown winter rape and winter wheat maintained higher net assimilation rates and higher in situ co2 exchange rates than the respective cold-grown spring cultivars. in particular, the relative growth rate of spring rape declined over time at low temperature, and this was associ ... | 1995 | 12228623 |
| amylolytic activities in cereal seeds under aerobic and anaerobic conditions. | an adequate carbohydrate supply contributes to the survival of seeds under conditions of limited oxygen availability. the amount of soluble, readily fermentable carbohydrates in dry cereal seeds is usually very limited, with starch representing the main storage compound. starch breakdown during the germination of cereal seeds is the result of the action of hydrolytic enzymes and only through the concerted action of [alpha]-amylase (ec 3.2.1.1), [beta]-amylase (ec 3.2.1.2), debranching enzyme (ec ... | 0 | 12228653 |
| low-temperature effects on photosynthesis and correlation with freezing tolerance in spring and winter cultivars of wheat and rye. | winter cultivars of rye (secale cereale l., cv musketeer) and wheat (triticum aestivum l. cvs kharkov and monopol), but not a spring cultivar of wheat (glenlea), grown at cold-hardening temperatures showed, at high irradiances, a higher proportion of oxidized to reduced primary, stable quinone receptor (qa) than did the same cultivars grown under nonhardening conditions. in addition, there was a positive correlation between the effects of low-growth temperature on this increased proportion of ox ... | 0 | 12231680 |
| purification and characterization of the voltage-dependent anion-selective channel protein from wheat mitochondrial membranes. | an approximately 29-kd protein was purified from the membrane fraction of wheat (triticum aestivum cv dganit) mitochondria by the utilization of standard liquid chromatography techniques. the protein, designated mmp29 for mitochondrial membrane protein having a molecular mass of approximately 29 kd, exhibited cationic properties in a buffering solution, adjusted to ph 7.5. this positive charge enabled its passage through a diethylaminoethyl column, without interaction with the positively charged ... | 1993 | 12231713 |
| inhibition of sucrose:sucrose fructosyl transferase by cations and ionic strength. | fructans are storage carbohydrates found in many temperate grasses. the first enzyme in the biosynthetic pathway of most fructans is sucrose:sucrose fructosyl transferase (sst). in this report, we demonstrate that k+ and ionic strength noncompetitively inhibit the activity of sst from wheat (triticum aestivum l.) stems. the ki for this inhibition is high, 122 mm, but in the range of concentrations of k+ found in the tissue (205-314 mm). addition of kcl to the assay system had no effect on the ph ... | 1993 | 12231714 |
| regulatory phosphorylation of c4 phosphoenolpyruvate carboxylase (a cardinal event influencing the photosynthesis rate in sorghum and maize). | c4 leaf phosphoenolpyruvate carboxylase (pepc; ec 4.1.1.31) is subject to a day/night regulatory phosphorylation cycle. by using the cytoplasmic protein synthesis inhibitor cycloheximide (chx), we previously reported that the reversible in vivo light activation of the c4 pepc protein-serine kinase requires protein synthesis. in the present leaf gas-exchange study, we have examined how and to what extent the chx-induced inhibition of pepc protein kinase activity/pepc phosphorylation in the light ... | 1993 | 12231740 |
| detection in vivo of very rapid red light-induced calcium-sensitive protein phosphorylation in etiolated wheat (triticum aestivum) leaf protoplasts. | etiolated wheat (triticum aestivum cv mercia) leaf protoplasts respond to brief red-light irradiation by increasing in volume over a 10-min incubation period (m.e. bossen, h.a. dassen, r.e. kendrick, w.j. vredenberg [1988] planta 174: 94-100). when the calcium-sensitive dye fluo-3 was incorporated into these protoplasts, red-light irradiation initiated calcium transients lasting about 2 min (p.s. shacklock, n.d. read, a.j. trewavas [1992] nature 358: 153-155). release of calcium in the protoplas ... | 1993 | 12231756 |
| wheat (triticum aestivum l.) [gamma]-gliadin accumulates in dense protein bodies within the endoplasmic reticulum of yeast. | following their sequestration into the endoplasmic reticulum (er), wheat storage proteins may either be retained and packaged into protein bodies within this organelle or transported via the golgi to vacuoles. we attempted to study the processes of transport and packaging of wheat storage proteins using the heterologous expression system of yeast. a wild-type wheat [gamma]-gliadin, expressed in the yeast cells, accumulated mostly within the er and was deposited in protein bodies with similar den ... | 1993 | 12231798 |
| aluminum effects on calcium (45ca2+) translocation in aluminum-tolerant and aluminum-sensitive wheat (triticum aestivum l.) cultivars (differential responses of the root apex versus mature root regions). | the influence of al exposure on long-distance ca2+ translocation from specific root zones (root apex or mature root) to the shoot was studied in intact seedlings of winter wheat (triticum aestivum l.) cultivars (al-tolerant atlas 66 and al-sensitive scout 66). seedlings were grown in 100 [mu]m cacl2 solution (ph 4.5) for 3 d. subsequently, a divided chamber technique using 45ca2+-labeled solutions (100 [mu]m cacl2 with or without 5 or 20 [mu]m alcl3, ph 4.5) was used to study ca2+ translocation ... | 1993 | 12231799 |
| group 3 late embryogenesis abundant proteins in desiccation-tolerant seedlings of wheat (triticum aestivum l.). | dormant seeds and young seedlings of wheat (triticum aestivum l.) tolerate desiccation. a transcript expressed in this desiccation-tolerant tissue has been cloned and sequenced (j. curry, c.f. morris, m.k. walker-simmons [1991] plant mol biol 16: 1073-1076). this wheat cdna clone encodes a protein that is homologous to other group 3 late embryogenesis abundant (lea) proteins. in this report, we describe the production of polyclonal antibodies to the protein product of the cdna clone and assess g ... | 1993 | 12231803 |
| two related biosynthetic pathways of mugineic acids in gramineous plants. | the biosynthesis of mugineic acids was studied by feeding 2h- or 13c-labeled compounds to water-cultured roots in several gramineous plants. the fate of labeled compounds was monitored by using 2h- and 13c-nuclear magnetic resonance. on investigating the proton changes during biosynthesis by feeding d,l-[3,3,4,4-d4]-methionine (98.6% 2h), 2h-labeled 2[prime]-deoxymugineic, mugineic, and 3-epihydroxymugineic acids were isolated from root washings of wheat (triticum aestivum l. cv minori), barley ... | 1993 | 12231828 |
| changes in the activities of anti-oxidant enzymes during exposure of intact wheat leaves to strong visible light at different temperatures in the presence of protein synthesis inhibitors. | changes in activities of the enzymes involved in the metabolism of active oxygen species were followed in homogenates prepared from wheat leaves (triticum aestivum l.) exposed to strong visible light (600 w m-2). the activities of superoxide dismutase (sod), ascorbate peroxidase, and monodehydroascorbate reductase increased significantly on prolonged illumination of the leaves, indicating an increase in the rate of generation of active oxygen species. this increase was further exacerbated when h ... | 1993 | 12231875 |
| interaction between aluminum toxicity and calcium uptake at the root apex in near-isogenic lines of wheat (triticum aestivum l.) differing in aluminum tolerance. | aluminum (al) is toxic to plants at ph < 5.0 and can begin to inhibit root growth within 3 h in solution experiments. the mechanism by which this occurs is unclear. disruption of calcium (ca) uptake by al has long been considered a possible cause of toxicity, and recent work with wheat (triticum aestivum l. thell) has demonstrated that ca uptake at the root apex in an al-sensitive cultivar (scout 66) was inhibited more than in a tolerant cultivar (atlas 66) (j.w. huang, j.e. shaff, d.l. grunes, ... | 1993 | 12231883 |
| rapid production of multiple independent lines of fertile transgenic wheat (triticum aestivum). | improvement of wheat (triticum aestivum) by biotechnological approaches is currently limited by a lack of efficient and reliable transformation methodology. in this report, we detail a protocol for transformation of a highly embryogenic wheat cultivar, bobwhite. calli derived from immature embryos, 0.5 to 1 mm long, were bombarded with microprojectiles coated with dna containing as marker genes the bar gene, encoding phosphinothricin-resistance, and the gene encoding [beta]-glucuronidase (gus), ... | 1993 | 12231889 |
| c4 photosynthesis (the co2-concentrating mechanism and photorespiration). | despite previous reports of no apparent photorespiration in c4 plants based on measurements of gas exchange under 2 versus 21% o2 at varying [co2], photosynthesis in maize (zea mays) shows a dual response to varying [o2]. the maximum rate of photosynthesis in maize is dependent on o2 (approximately 10%). this o2 dependence is not related to stomatal conductance, because measurements were made at constant intercellular co2 concentration (ci); it may be linked to respiration or pseudocyclic electr ... | 1993 | 12231916 |
| characterization of the early stages of genetic salt-stress responses in salt-tolerant lophopyrum elongatum, salt-sensitive wheat, and their amphiploid. | eleven unique cdna clones corresponding to genes showing enhanced mrna accumulation in the early stages of salt stress (early salt stress induced, esi) were previously isolated. the accumulation of these mrnas in lophopyrum elongatum (host) a. love, salt-sensitive wheat (triticum aestivum l.), and their amphiploid is compared. the accumulation of esi mrnas was much greater in the l. elongatum roots than in the shoots. additionally, mrna accumulation in the roots of the three genotypes showed a b ... | 1993 | 12231932 |
| transpiration induces radial turgor pressure gradients in wheat and maize roots. | previous studies have shown both the presence and the absence of radial turgor and osmotic pressure gradients across the cortex of roots. in this work, gradients were sought in the roots of wheat (triticum aestivum) and maize (zea mays) under conditions in which transpiration flux across the root was varied this was done by altering the relative humidity above the plant, by excising the root, or by using plants in which the leaves were too young to transpire. roots of different ages (4-65 d) wer ... | 1993 | 12231957 |
| aluminum tolerance in wheat (triticum aestivum l.) (i. uptake and distribution of aluminum in root apices). | we investigated the uptake and distribution of al in root apices of near-isogenic wheat (triticum aestivum l.) lines differing in al tolerance at a single locus (alt1: aluminum tolerance). seedlings were grown in nutrient solution that contained 100 [mu]m al, and the roots were subsequently stained with hematoxylin, a compound that binds al in vitro to form a colored complex. root apices of al-sensitive genotypes stained after short exposures to al (10 min and 1 h), whereas apices of al-tolerant ... | 1993 | 12231972 |
| aluminum tolerance in wheat (triticum aestivum l.) (ii. aluminum-stimulated excretion of malic acid from root apices). | we investigated the role of organic acids in conferring al tolerance in near-isogenic wheat (triticum aestivum l.) lines differing in al tolerance at the al tolerance locus (alt1). addition of al to nutrient solutions stimulated excretion of malic and succinic acids from roots of wheat seedlings, and al-tolerant genotypes excreted 5- to 10-fold more malic acid than al-sensitive genotypes. malic acid excretion was detectable after 15 min of exposure to 200 [mu]m al, and the amount excreted increa ... | 1993 | 12231973 |
| synergistic enhancement of the antifungal activity of wheat and barley thionins by radish and oilseed rape 2s albumins and by barley trypsin inhibitors. | although thionins and 2s albumins are generally considered as storage proteins, both classes of seed proteins are known to inhibit the growth of pathogenic fungi. we have now found that the wheat (triticum aestivum l.) or barley (hordeum vulgare l.) thionin concentration required for 50% inhibition of fungal growth is lowered 2- to 73-fold when combined with 2s albumins (at sub- or noninhibitory concentrations) from radish (raphanus sativus l.) or oilseed rape (brassica napus l.). furthermore, t ... | 1993 | 12232024 |
| monitoring phloem unloading and post-phloem transport by microperfusion of attached wheat grains. | phloem unloading and post-phloem transport in developing wheat (triticum aestivum l.) grains were investigated by perfusing the endosperm cavities of attached grains. relative unloading ratio (rur) and the rate of sucrose release into the endosperm cavity (srr) were calculated, respectively, from 14c import and from sucrose washout from the cavity. rur and srr continued at or near in vivo rates over a wide range of cavity sap osmolality (90 to approximately 500 milliosmolal) and sucrose concentr ... | 1994 | 12232056 |