Variation of Nuclear DNA Content in the Biflorus Species of Lonchocarpus (Leguminosae)

This represents the first study of nuclear DNA content in alarge sample (135 spp.) from a tropical arboreal genus, in whicha large proportion of the species were examined (42 spp., 31.1%).Somatic chromosome numbers and 4C-DNA values for 51 taxa ofLonchocarpus are reported. All taxa were diploid with 2 n =22,but their DNA content ranged from 1.92 to 2.86 pg 4C nucleus,corresponding to a 48.95% variation in genome size. In the 74collections studied, no correlation was observed between DNAcontent and habitat altitude. Variation in nuclear DNA contentwas analysed at the level of genus, subgenus, section and subsection.Variation in genome size was also studied within some species,either among widely separated populations or among differentintraspecific taxa. Very little variation in genome size wasdetected between populations, subspecies, and varieties of thesame species. The taxonomic implications of variation in nuclearDNA content are discussed.Copyright 2000 Annals of Botany Company Lonchocarpus (Leguminosae), DNA content, chromosome number.     

Use of fluorescence genomic in situ hybridization (GISH) to detect the presence of alien chromatin in wheat lines differing in nuclear DNA content

BACKGROUND: Many times small differences in genome size are reported between or within plant species in which no cytologic confirmation is made. Attempts to repeat these studies have met with limited success. The controversy then becomes whether or not these small differences that were not confirmed cytologically are real. The present study was undertaken to determine if the approximately 1% nuclear variation seen by flow cytometry among wheat lines selected for aluminum response was due to actual chromatin differences. METHODS: The three parental wheat cultivars used in the aluminum selection along with the isolines resulting from the selection were analyzed. One parental line had previously been reported to have alien chromatin substituted for the corresponding wheat homologous chromatin. Genomic in situ hybridization was used to determine the presence or absence of rye chromatin in three cultivars and six near-isolines of wheat. RESULTS: Upon observing metaphase chromosomes of the Century parent and its isolines, two of the chromosomes were observed to be one-half yellow-orange, indicating rye chromatin with the remaining portion of the chromosomes and the other 40 wheat chromosomes having no label indicating wheat chromatin. In the Chisholm parent and its isolines, none of the chromosomes were labeled, indicating the absence of rye chromatin. In addition, none of the third parents' chromosomes had the rye yellow-orange signal. CONCLUSIONS: The wheat lines with the larger DNA contents were observed to have alien DNA present. DNA differences between the normal wheat chromosomes and the substituting alien chromatin were calculated based on total chromosome length. The increase in genome size of the wheat lines containing the alien chromatin appears to be the result of the alien chromatin having approximately 43% more DNA than the wheat chromatin it is replacing. Thus, the small DNA difference previously reported by flow cytometry was demonstrated to be a real DNA variation due to the presence of small fragments of alien chromosomes added to the wheat genome.     

Nuclear DNA Content Diversity in Chinese Soybean Introductions

Intraspecific nuclear DNA content has been documented in variousangiosperm species. The purpose of this study was to determinethe nuclear DNA content variation in soybean (Glycine max(L.)Merr.). Several studies have suggested that DNA content variationexists in soybean. Ninety soybean lines representing diversegeographic locations in China were analysed by flow cytometry.Nuclei were isolated and stained with either the fluorochromeDAPI or PI. After analysis, it was determined that PI stainednuclei more accurately assessed the total DNA content in soybean.A 12% variation in nuclear DNA content was observed among the90 lines. The amount of nuclear DNA in the lines was withinthe DNA range of United States cultivars previously examined.Nuclear DNA content variation in soybean is much less than thevariation reported in maize. These results could be due to thelack of polymorphism in large chromosomal elements containinglarge blocks of repetitive DNA. In addition, unlike maize, theamounts of DNA variation did not decrease as a result of moreintensive breeding in United States cultivars. Intraspecificnuclear DNA content variability is very different between thesetwo major agronomic species. Glycine max(L.) Merr.; germplasm; genome size     

Growth of Near-isogenic Wheat Lines Differing in Development--Spaced Plants

The relationship between phenological development in wheat (TriticumaestivumL.) and growth was studied to determine if the switchfrom a vegetative to a reproductive apex increases plant growthrate. Plant partitioning and relative growth rates during vegetativeand pre-flowering reproductive periods were determined in twosets of near-isogenic lines differing in phenological development.Spaced plants were grown in two photoperiods (15 and 10 h) toincrease the range of development rates. Lines within each isogenicset and photoperiod treatment did not differ in whole plantgrowth rate despite large differences in developmental rate.In addition, the partitioning of biomass between roots and shootswas also similar. The transition of the apex from vegetativeto reproductive mostly affected the partitioning of shoot biomassinto leaf (blades) and stems (rest of the shoot). A longer timeto reach floral initiation was associated with the productionof more, and larger, leaves as well as more tillers. This resultedin large differences in leaf area between isolines. However,at the whole plant level, all lines accumulated biomass at thesame rate with time. The early flowering lines compensated fortheir reduced leaf area by having a higher net assimilationrate and were thereby able to maintain the same relative growthrate as their later flowering counterparts.Copyright 1998 Annalsof Botany Company Development, growth, partitioning,Triticum aestivumL., wheat, isolines.     

Several lanthanides activate malate efflux from roots of aluminium‐tolerant wheat

Many elements of the lanthanide series exist as trivalent cations in solution below pH 6. The present study was carried out to investigate whether lanthanides could stimulate malate efflux from wheat (Triticum aestivum L.) roots, as has been found for trivalent aluminium (Al) cations. Excised root apices treated with 100 µm of each of seven different lanthanide elements (lanthanum, praseodymium, europium, gadolinium, terbium, erbium, and ytterbium) stimulated malate efflux, with five‐ to fifty‐fold more malate being released from an Al‐tolerant wheat line than from a near‐isogenic Al‐sensitive line. As erbium stimulated the greatest malate efflux of the lanthanides tested, this response was characterized further. The characteristics of the erbium‐activated efflux were similar to the Al‐activated efflux described previously suggesting that both of these ions activate the same transport mechanism. The capacity for erbium‐activated malate efflux cosegregated with Al tolerance in wheat seedlings derived from a cross between Al‐sensitive and Al‐tolerant near‐isogenic lines. This is the first study to identify cations, other than Al, which can activate malate release from wheat roots. It also provides additional evidence that malate efflux from root apices is the primary mechanism for Al tolerance in wheat.     

Nuclear DNA Content of 26 Orchid (Orchidaceae) Genera with Emphasis onDendrobium

2C DNA content values for 70 orchid species from 26 genera,including 37Dendrobiumspecies from eight taxonomic sections,were analysed using flow cytometry. The resulting nuclear DNAcontent values for species other thanDendrobiumranged from 1.91pg 2C^-1to 15.19 pg 2C^-1nuclei forCadetia tayloriandVanilla phaeantha,respectively.Dendrobiumnuclear DNA content values ranged from1.53 pg 2C^-1to 4.23 pg 2C^-1nuclei forD. cruentumandD. spectabile,respectively. DNA content measurements varied greatly withinDendrobiumsectionsLatouria and Spatulata. Nuclear DNA content values for the sixspecies analysed within Latouria ranged from 1.88 pg 2C^-1nucleiforD. macrophyllumto 4.23 pg 2C^-1nuclei forD. spectabile. NuclearDNA content values for the 16 species analysed within Spatulataranged from 1.69 pg 2C^-1nuclei forD. discolorto 4.05 pg 2C^-1nucleiforD. samoense. The least variation in DNA content was foundwithin the section Phalaenanthe, with nuclear DNA content valuesof 1.79 pg  2C^-1, 1.86 pg 2C^-1and 1.98 pg 2C^-1forD. bigibbum,D.affineandD. phalaenopsis, respectively.Copyright 1998 Annalsof Botany Company Orchidaceae,Dendrobium, flow cytometry, propidium iodide, nuclear DNA, genome size, 2C values.     

Mitotic instability in wheat×Thinopyrum ponticum derivatives revealed by chromosome counting, nuclear DNA content and histone H3 phosphorylation pattern

To evaluate the mitotic stability of Triticum aestivum×Thinopyrum ponticum derivatives (BC₂F₇ and BC₂F₅ doubled haploids), chromosome counting by both conventional and immunostaining techniques, and measurement of DNA content were performed. The wheat progenitor line, PF 839197, the wheat recurrent parent CEP 19 and the control Chinese Spring were also investigated. In the hybrid derivatives, chromosome number ranged from 2n=36 to 60, with a predominance of chromosome numbers higher than 2n=42, that was confirmed by determination of nuclear DNA content. Chinese Spring and PF 839197 were stable, but CEP 19 showed chromosome number variation (20%). Analyses of non-pretreated cells revealed the presence of anaphase bridges, lagging chromatids, chromosome fragments and micronuclei. Immunostaining with an antibody recognizing histone H3 phosphorylated showed dicentric chromatids forming anaphase bridges and pericentromeric phosphorylation at centric chromosome fragments but not at lagging chromatids. The possible causes of the observed mitotic instability are discussed.     

Nuclear DNA Content in Twelve Species of Alstroemeria L. and Some of their Hybrids

Nuclear DNA content (2C-value), estimated through flow cytometryusing propidium iodide (PI), was shown to vary from 36.5 pgto 78.9 pg among 29 accessions of 12Alstroemeria species (2n=2x =16). The extremes were found inA. magnifica ssp.magnificaand inA. ligtu ssp.simsii , both belonging to the Chilean speciesgroup. The four Brazilian species exhibited less variation innuclear DNA content (49.8–56.4 pg), than the eight Chileanspecies (36.5–78.9 pg). Nuclear DNA content was positivelycorrelated (r =0.92,n =7,P <0.01) with the total chromosomelength. It was also positively correlated (r =0.85,n =5,P <0.01)with the length of C-bands, when only the Chilean species wereconsidered. When both karyotype parameters, length of non-C-bandedchromosome regions (x) and length of C-bands (y) were determined,it was possible to predict the nuclear DNA content (z) withthe formula z=0.65x +1.31y-0.45 (R ²=0.97,P =0.004). The DAPI fluorescence of most accessions was proportional tothe PI fluorescence (r =0.98,P <0.001), except for one accessionofA. ligtu , that had a relatively high PI/DAPI ratio (1.88).The PI/DAPI ratios of the Brazilian species were lower (1.59–1.67)than those of the Chilean species (1.68–1.88), which mightreflect a difference in base pair composition. Four groups ofspecies could be distinguished on the basis of fluorescencevalues. Diploid interspecific hybrids were shown to have a DNAcontent intermediate to the values of the parents involved.Both the PI and the DAPI fluorescence values of these hybridsapproximated the mid parent values. Tetraploids, derived fromselfing of diploids, had PI and DAPI fluorescence values thatwere twice that of the diploid hybrids. It was possible to distinguishaneuploids from euploids based on fluorescence values. Alstroemeria ; aneuploidy; C-banding; DAPI; evolution; flow cytometry; genome size; geophytes; karyotypes; Inca Lily; nuclear DNA; propidium iodide     

Expression of Vernalization Genes in Near-lsogenic Wheat Lines: Duration of Vernalization Period

Vernalization periods ranging from 0 to 11 weeks at 4 °Cwere used to study the reproductive development of four near-isogeniclines of wheat (Triticum aestivum L. em. Thell). From the resultsfor days to anthesis two types of gene action were identified,a threshold (all-or-nothing) response (vrn3 and/or vrn4) anda cumulative (graded) response (vrn1). The action of anothergene (vrn2) intensified these two responses. Based on the actionof genes, a model relating days to anthesis to genotype wasderived. Final leaf number and days to anthesis were shown tobe closely related after adjusting for differences due to theduration of vernalization treatment. No relationship betweendays to anthesis and spikelet number was observed. This studyemphasises the need to understand vernalization at the levelof the gene in terms of responses and interactions. Such knowledgeshould enable the plant breeder to predict and more preciselycontrol reproductive development. Triticum aestivum L., wheat, vernalization, gene action, isogenic lines     

Aluminum stress and protein synthesis in near isogenic lines of Triticum aestivum differing in aluminum tolerance

Aluminum (Al) stress was examined in three lines of wheat ( Triticum aestivum L.) by measuring root lengths, protein synthesis and protein accumulation in seedling root tips grown in a hydroponic system. An Al-sensitive, recurrent wheat parent (cv. Katepwa) showed very little root growth in low Al concentrations. In contrast, an Al-tolerant near isogenic line (Alikat) and Al-tolerant donor (cv. Maringa) had much greater root growth. Segregation data from an F₂ population (Katepwa × Alikat) showed that one major gene controlled Al tolerance based on root growth ( X ²= 0.651). All three lines showed an approximately 2-fold increase in [³⁵S]-Met incorporation in root tips after 3 days in Al and a comparable increase in root-tip dry weight. Maringa and Alikat root tips showed an increased total protein content while Katepwa root tips showed no increase in total protein content during the Al stress. Based on higher specific activities, insoluble proteins were preferentially translated in all three lines during Al stress. Proteinase activity in Katepwa root tips was 1.7-fold higher during Al stress, with Maringa and Alikat showing no change in proteinase activity. The Al-induced, increased proteinase activity in Katepwa appeared to inhibit soluble protein accumulation.     

Aluminium tolerance of root hairs underlies genotypic differences in rhizosheath size of wheat (Triticum aestivum) grown on acid soil

We found significant genetic variation in the ability of wheat (Triticum aestivum) to form rhizosheaths on acid soil and assessed whether differences in aluminium (Al(3+) ) tolerance of root hairs between genotypes was the physiological basis for this genetic variation. A method was developed to rapidly screen rhizosheath size in a range of wheat genotypes. Backcrossed populations were generated from cv Fronteira (large rhizosheath) using cv EGA-Burke (small rhizosheath) as the recurrent parent. A positive correlation existed between rhizosheath size on acid soil and root hair length. In hydroponic experiments, root hairs of the backcrossed lines with large rhizosheaths were more tolerant of Al(3+) toxicity than the backcrossed lines with small rhizosheaths. We conclude that greater Al(3+) tolerance of root hairs underlies the larger rhizosheath of wheat grown on acid soil. Tolerance of the root hairs to Al(3+) was largely independent of the TaALMT1 gene which suggests that different genes encode the Al(3+) tolerance of root hairs. The maintenance of longer root hairs in acid soils is important for the efficient uptake of water and nutrients.     

Nuclear DNA Metabolism in the Tip of the Cortical Strands of Viscum album L

The tips of the cortical strands of Viscum album were investigatedby autoradiographic and cytophotometric methods. It is shown that DNA synthesis and mitotic activity of the sub-apicalmeristematic cells are constant during the whole year. Theirnuclear DNA content varies from 2C to 4C values. The elongated cells which cover the meristematic zone are characterizedby no DNA synthesis, no mitotic activity and a 2C nuclear DNAcontent. They are ‘blocked’ in the presyntheticphasc G₁ of their cellular cycle, without polyploidy. The relationship between polyploidy and secretion is discussed. Viscum album, mistletoe, nucleus, DNA, polyploidy     

Gametoclonal variation detected in the nuclear ribosomal DNA from doubled haploid lines of a spring wheat (Triticum aestivum L., cv. ‘César’)

Summary The organization of the nuclear ribosomal DNA from a parental line of wheat (Triticum aestivum L., cv. César) and its anther-derived first cycle and second cycle doubled haploid lines has been analyzed by DNA-DNA molecular hybridization. Restricted DNA has been probed by three subclones of wheat nuclear ribosomal DNA covering the entire repeat unit. No significant difference was detected in the extent of methylation of ribosomal DNA of the doubled haploid lines with respect to the parental line. On the other hand, a variation has been found in the organization of the nontranscribed spacer region of ribosomal DNA of the first cycle doubled haploid line. This variation remains stable after a second cycle of in vitro androgenesis. However, one out of five second cycle doubled haploid lines so far tested showed an additional hybridization band present in the parental line but lacking in the first cycle doubled haploid line.     

Photoperiod and Vernalization Responses in Triticum turgidumxT. tauschii Synthetic Hexaploid Wheats

Studies of synthetic hexaploid wheat developed from Triticumturgidum(AABB genomes) and T. tauschii(DD genome) can provideinformation on potentially useful characters in T. tauschiiand/or T. turgidum for genetic improvement of hexaploid wheat(T. aestivum). Synthetic hexaploid wheats and the T. turgidumand T. tauschii parents were assessed for their developmentalresponses to photoperiod and vernalization for days to ear emergence,final leaf number and the number of spikelets per spike. Theresponses to photoperiod and vernalization of the synthetichexaploids were generally intermediate between those of theparents but in some instances the levels of expression exhibitedby the T. tauschii or T. turgidum parents were epistatic inthe synthetic hexaploids. The relatively strong photoperiodresponse of the T. tauschii accessions was not expressed inthe synthetic hexaploids, but rather the synthetic hexaploidsreflected the photoperiod response of the respective T. turgidumparents. The synthetic hexaploids had vernalization responsesstronger than those of the T. turgidum and bread wheats usedin the study. The expression of ear emergence in response tovernalization of these synthetic hexaploids appeared to be modifiedby the T. turgidum parent. Copyright 2001 Annals of Botany Company Photoperiod, synthetic hexaploids, Triticum aestivum, Triticum tauschii, Triticum turgidum, vernalization     

The Nature and Duration of Gene Action for Vernalization Response in Wheat

Four near-isogenic lines of wheat were studied to determinethe nature and duration of gene action for vernalization responseunder 2 weekly vernalization periods from 0 to 10 weeks. With time to floral initiation the Vrn 1 Vrn 2 and Vrn 1 vrn2 genotypes showed a cumulative response whereby days to floralinitiation decreased as the period of vernalization increased.The vrn 1 Vrn 2 and the vrn 1 vrn 2 genotypes also showed acumulative response for periods of vernalization less than 6weeks for the former and 8 weeks for the latter. Days to earemergence was closely related to days to floral initiation dueto the constancy of the period from floral initiation to earemergence across all lines and treatments and, consequently,they gave similar measures of the relative strength of vernalizationresponse. It appears that genes for vernalization response ceaseto act after floral initiation. The implications of these findings to breeding for increasedadaptability and yield in wheat are discussed. Triticum aestivum, wheat isogenic lines, vernalization, floral initiation, ear emergence, gene action     

Cytoplasmic effects on DNA methylation between male sterile lines and the maintainer in wheat (Triticum aestivum L.)

Male sterile cytoplasm plays an important role in hybrid wheat, and three-line system including male sterile (A line), its maintainer (B line) and restoring (R line) has played a major role in wheat hybrid production. It is well known that DNA methylation plays an important role in gene expression regulation during biological development in wheat. However, no reports are available on DNA methylation affected by different male sterile cytoplasms in hybrid wheat. We employed a methylation-sensitive amplified polymorphism technique to characterize nuclear DNA methylation in three male sterile cytoplasms. A and B lines share the same nucleus, but have different cytoplasms which is male sterile for the A and fertile for the B. The results revealed a relationship of DNA methylation at these sites specifically with male sterile cytoplasms, as well as male sterility, since the only difference between the A lines and B line was the cytoplasm. The DNA methylation was markedly affected by male sterile cytoplasms. K-type cytoplasm affected the methylation to a much greater degree than T-type and S-type cytoplasms, as indicated by the ratio of methylated sites, ratio of fully methylated sites, and polymorphism between A lines and B line for these cytoplasms. The genetic distance between the cytoplasm and nucleus for the K-type is much greater than for the T- and S-types because the former is between Aegilops genus and Triticum genus and the latter is within Triticum genus between Triticum spelta and Triticum timopheevii species. Thus, this difference in genetic distance may be responsible for the variation in methylation that we observed.     

Influence of Vernalization and Photoperiod on Supernumerary Spikelet Expression in Wheat

Two tetraploid (Triticum turgidum L.emend gr. turgidum and gr.durum) and five hexaploid wheats (Triticum x aestivum L. emendgr. aestivum) with reported tendencies for ‘branched heads’(supernurnerary spikelets) exhibited variation in its expressionunder different vernalization photoperiod and temperature regimes. Two main types of supernumerary spikelets were identified, multiplesessile spikelets (MSS) with two or more complete spikeletsat a rachis node and indeterminate rachilla spikelets (IRS)with two to 13 spikelets on an extended rachilla. The degree of supernumerary spikelet expression in wheats withvernalization response differed from those without. Short photoperiods(9–14 h) both outdoors and in a glasshouse environment,were more conducive to supernumerary spikelet expression than24 h photoperiod in both environments. The 24 h photoperiodglasshouse environment (higher mean temperatures) was leastconducive to its expression except in lines with a strong vernalizationresponse. The high stability of supernumerary spikelet expression in certaingenotypes in the different environments indicated the feasibilityof incorporating this character in breeding and selecting commercialwheats to increase grain number per head. Triticum, wheat, ear-branching, supernumerary spikelets, vernalization, photoperiod, temperature     

Effects on Growth and Development of Individual Chromosomes from Slow-growing Lophopyrum elongatum Love when Incorporated into Bread Wheat (Triticum aestivum L.)

Aspects of growth and development were evaluated in the fast-developingannual Triticum aestivum L. ‘Chinese Spring’, theslow-developing perennial Lophopyrum elongatum Löve, theiramphiploid, and chromosome addition and substitution lines ofL. elongatum into ‘Chinese Spring’. Relative growthrates (RGR) of shoots of L. elongatum and the amphiploid werelower than those of ‘Chinese Spring’ (34 and 13%respectively) and main stem development was also slower. Therewas no difference in shoot RGR of any of the chromosome additionor substitution lines and that of ‘Chinese Spring’when assessed between Haun stages 2.0 and 5.0. In contrast,several aspects of plant development were observed to differin the chromosome addition and substitution lines. SubstitutingE genome chromosomes (with the exceptions of 3E and 4E) forD genome chromosomes, or adding E genome chromosomes, slowedthe rate of main stem development, at least up to Haun stage5.0. Despite these differences in the rate of main stem development,the appearance of adventitious roots commenced at approximatelyHaun stage 2.0 in all genotypes. However, the numbers of adventitiousroots and tillers at the 5.0 Haun stage differed between someof the lines when compared to ‘Chinese Spring’.Although incorporation of some L. elongatum chromosomes alteredaspects of plant development, all lines showed more similarityto bread wheat than to L. elongatum, reflecting, in part, thegreater genetic contribution made by bread wheat to these lines.Copyright 2001 Annals of Botany Company Adventitious roots, chromosome addition and substitution lines, Haun stage, Lophopyrum elongatum, relative growth rate (RGR), Triticum aestivum(wheat)     

Determining relative abundance of specific DNA sequences in flow cytometrically sorted maize nuclei

A wide breadth of DNA content variation has been reported amongmaize lines. While the extent of this variation has been welldocumented, few studies have focused on its cause. Some of thenuclear DNA content variation has been explained by the presenceof B chromosomes or knobs. However, variation in these two structuresdoes not account for all of the observed variation. In orderto identify other fluctuating DNA sequences, a rapid and reliablemethod of estimating relative abundance of DNA sequences neededto be developed. The potential of flow cytometry in conjunctionwith spot hybridization for determining relative abundance ofspecific DNA sequences in maize was studied. Different numbersof G1 phase nuclei were sorted on nitrocellulose filters andnon-radioactive hybridization and signal detection performed.Results from these experiments revealed a significant, positivelinear correlation between the amount of target sequence andsignal density using both knob (R = 0.98) and ribosomal spacer(R =0.99) DNA sequences. In addition, G1 phase nuclei of eightinbred lines differing in the amount of knob heterochromatin,were sorted on to filters and the non-radioactive hybridizationand signal detection performed. A significant, positive linearcorrelation between C-band number and signal density (R =0.83;P = 0.0051) as well as between per cent heterochromatin andsignal density (R=0.96;P = 0.0002) was observed. These resultsindicate the usefulness of flow cytometry for spot hybridizationin determining the relative abundance of DNA sequences in themaize genome. Key words: Flow cytometry, copy number, non-isotope labelling, spot hybridization, flow sorting, Zea mays L.     

Effect of Irradiance on Chlorophyll Estimation with the Minolta SPAD-502 Leaf Chlorophyll Meter

Leaf chlorophyll content may be used as an indirect indicatorof crop nitrogen status. Chlorophyll meter values (SPAD values)taken with the Minolta SPAD-502 chlorophyll meter in the shadeplantOxalis acetosellaL. and in winter wheat (Triticum aestivumL.)varied by 15 and 8%, respectively, with variation in irradiance.The lowest SPAD-values were measured at high irradiance. Duringa natural night-day-night cycle SPAD values for winter wheatwere lowest in the middle of the day, highest at low irradianceat dusk and dawn and intermediate in darkness before dawn andafter dusk. The results indicate that irradiance during measurementshould be considered when using the Minolta SPAD-502 chlorophyllmeter for the estimation of crop N-status.Copyright 1998 Annalsof Botany Company Chlorophyll meter, nitrogen, irradiance,Oxalis acetosellaL.,Triticum aestivumL., winter wheat.