Formation of phenol compounds in various cultivars of wheat (Triticum aestivum L.)

The formation of soluble phenol compounds, including flavonols, was studied in winter (Erythrospermum, Lutescens 230, and R 47-28) and spring cultivars (Lada) of wheat (Triticum aestivum L.). The contents of soluble phenol compounds and flavonols were 1.8-2.6 and 0.5-1.3 mg/kg fresh weight, respectively. These results illustrate the similarity of phenol metabolism in leaves of winter and spring wheat cultivars. The exception was the cultivar R 47-28 that accumulated the maximum amount of phenol compounds (e.g., flavonols). In this cultivar the ratio of flavonols reached 50% of total soluble phenol content. In other cultivars, this parameter did not exceed 25-35%. The data indicate that the cultivar R 47-28 differs from other wheat cultivars in the metabolism of phenol compounds. The observed differences are probably related to genetic modifications of the cultivar R 47-28 during selection.     

Activity of Lectins of Winter Wheat Seedlings Infected with Mycoplasma and Treated with Salicylic Acid

Changes in activity of soluble and cell wall lectins have been revealed in seedlings of winter wheat Triticum aestivum L. cultivar Mironovskaya 808 after infection with mycoplasma Acholeplasma laidlawii 118. The protective effect of salicylic acid was manifested as negating the bursts of lectin activity induced by mycoplasma infection.__________Translated from Izvestiya Akademii Nauk, Seriya Biologicheskaya, No. 4, 2005, pp. 423–427.Original Russian Text Copyright © 2005 by Trifonova, Maksyutova, Timofeeva, Chernov.     

Revealing Hereditary Variation of Winter Hardiness in Cereals

A set of cereal crops and differentiating cultivars was shown to be of utility for identifying the major abiotic factors that limit the survival of winter crops in the cold season of a particular year. With this approach, the season was identified (1997–1998, Belgorod) when the survival of cereals depended on the tolerance to anaerobiosis rather than on the frost resistance. Differentiation of common wheat cultivars with respect to this property was attributed to a locus designated Win1 (Winter hardiness 1) and localized 3.2–5.8% recombination away from the B1 (awnlessness 1) gene. Winter barley (cultivar Odesskii 165) displayed the highest tolerance to anaerobiosis in the cold season; low and intermediate tolerance was established for winter durum wheat (cultivar Alyi Parus) and winter common wheat, respectively. Frost resistance and winter hardiness type 1 proved to be determined by different genetic systems, which showed no statistical association. Correlation analysis revealed significant positive associations of frost resistance in the field (1996–1997, Belgorod) with productivity, sedimentation index (Zeleny test), plant height, and vegetation period in wheat. Statistical analysis associated frost resistance with gliadin-coding alleles of homeologous chromosomes 1 and 6 of the A, B, and D wheat genomes.     

Plant regeneration through callus initiation from thin mature embryo fragments of wheat

A wheat regeneration system was developed using mature embryos. Embryos were removed from surface-sterilised mature caryopses (winter wheat Odeon cultivar and spring wheat Minaret cultivar) and ground to pieces through a sterile nylon mesh. The fragments were characterised by means of the image analysis technique. They were 500 M mean diameter and most of them were elongated. They were used as explants to initiate embryogenic calli on solid medium supplemented with 10 M 2,4-dichlorophenoxyacetic acid. The morphogenic pathway of the initiated calli was followed for a 40-day culture period. Active cellular division occurred within 24 hours of cultivation. Several hundred calli were produced from 100 fragmented embryos within 3 days. A 90% callus induction rate was achieved and proembryos appeared by the 8th day of culture. The highest embryogenic calli induction rate of 47% was obtained when 2,4-dichlorophenoxyacetic acid was suppressed after a 3–4 week induction period. Two regeneration methods were finally compared. A total of 513 plantlets were produced. The optimal protocol produced 25–30 plants per 100 embryos. This regeneration method may be suitable for transformation applications.     

The Effects of Cold Acclimation of Winter Wheat Plants on Changes in CO<Subscript>2</Subscript> Exchange and Phenolic Compound Formation

We studied CO₂ exchange and phenolic compound production in various organs of unhardened and hardened winter wheat (Triticum aestivum L.) plants. The rates of CO₂ assimilation at saturating illumination (photosynthesis) and CO₂ evolution in darkness (respiration) declined substantially at the autumnal decrease of ambient temperature. However, because of a higher cold resistance of photosynthesis, the ratio of photosynthesis to respiration rates increased 1.5-fold. These gas exchange changes were accompanied by the accumulation of total soluble phenolics in leaves and a polymeric phenolic compound lignin in roots. We did not observe any changes in the production of either soluble or polymeric (lignin) phenolics in crowns.__________Translated from Fiziologiya Rastenii, Vol. 52, No. 3, 2005, pp. 366–371.Original Russian Text Copyright © 2005 by Zagoskina, Olenichenko, Klimov, Astakhova, Zhivukhina, Trunova.     

Assessing cultivar resistance to Sitodiplosis mosellana (Géhin) (Diptera: Cecidomyiidae) using a phenotyping method under semi‐field conditions

The orange wheat blossom midge, Sitodiplosis mosellana (Géhin), can significantly reduce wheat yield. Growing resistant wheat cultivars is an effective way of managing this pest. The assessment of cultivar resistance in field trials is difficult because of unequal pressure of S. mosellana caused by differences in cultivar heading dates relative to the flight period of S. mosellana adult females and huge variations of egg laying conditions from 1 day to another. To overcome these hurdles and to expose all cultivars homogeneously to the pest, an assessment method of cultivar resistance was developed under semi‐field conditions. In 2015, the resistance of 64 winter wheat cultivars to S. mosellana was assessed. Few or no larvae developed in the ears of resistant cultivars, but in susceptible cultivars, large numbers of larvae developed. Seventeen cultivars proved to be resistant, whereas 47 were susceptible. The identification of new resistant cultivars offers more opportunities to manage S. mosellana. The phenotyping method is easy, cheap, efficient and reliable. It can be used to guide the breeding of new resistant wheat cultivars. Using specific midge populations, this method could also be used in research on new resistance mechanisms in winter wheat or in other cereal species.     

The effect of low temperature on the microtubules in root meristem cells of spring and winter cultivars of wheat <Emphasis Type="Italic">Triticum aestivum L.</Emphasis>

We have studied the response of interphase and mitotic microtubule arrays in root meristem cells of spring and winter cultivars of wheat Triticum aestivum L. (Moskovskaya 35 and Moskovskaya 39) to cold stress (1 h at 0°C) and acclimation to cold (3–48 h at 0°C). We show that, in general, interphase microtubules are more resistant to cold then mitotic arrays in both cultivars. During cold stress, no changes are detected in the microtubule system of interphase cells of spring wheat, whereas the density of endoplasmic microtubules increases in interphase cells of winter wheat. During mitosis, the density of the kinetochore fibers of the spindle decreases in the cells of both cultivars, but it is prevailing in the cells of spring cultivar of wheat. During acclimation to cold, the disorganization of the cortical microtubule bundles and the enhanced growth of the endoplasmic microtubule network, which is comprised of microtubule converging centers, are observed in cells of both cultivars. However, the mitotic microtubule systems of winter and spring cultivars respond differently to cold acclimation. During prophase, a diffuse tubulin “halo,”followed by the assembly of microtubule converging centers, accumulate at the perinuclear area in the cells of winter wheat. In cells of spring cultivar, the prophase spindle is only detected during initial stages of cold acclimation. During metaphase, aberrant mitotic spindles, abnormal metaphase plates, and the excessive appearance of microtubule converging centers are observed in cells of both cultivars. Acclimation induces the disorganization of the phragmoplast and the formation of multiple microtubule converging centers during telophase in the cells of both cultivars. Microtubule converging centers are detected at the perinuclear area of daughter cells in winter wheat and in the cortical cytoplasm in spring wheat. The excessive formation of microtubule converging centers suggests the activation of microtubule assembly during prolonged exposure to low temperature. Our data also demonstrates common pathways of microtubule response to cold treatment (0°C).     

Effect of genotype and medium on wheat (Triticum aestivum L.) anther culture

Four winter wheat (Triticum aestivum L.) and two spring wheat cultivars were evaluated in anther culture on three to four different media for their ability to initiate callus and green plants. Five media were used in the experiment: stored-potato medium with Ficoll 400, fresh-potato medium with Ficoll 400, fresh-potato medium with agar, fresh-potato liquid medium without agar or Ficoll 400, and a one tep 85D12-3 medium. Greatly different frequencies of calli and/or green plants were obtained from different cultivars and media. The callus initiation frequency varied from 2.7% for Arapahoe to 52% for Pavon, both on the stored potato medium with Ficoll 400. The frequency of green plant regeneration ranged from 0% for Arapahoe and Siouxland on the stored-potato medium with Ficoll 400 and 0% for Redland and Arapahoe in the fresh-potato medium with Ficoll 400 to 12% for Chris in the 85D12-3 medium (one-step procedure). Chris and Centurk 78, previously reported as having high levels of response, had significantly higher (P < 0.05) frequencies of green plant regeneration on the 851312-3 medium than the other cultivars. An unexpected observation is that wet MSC^– medium enhanced callus regeneration more than a drier MSC^– medium.     

Effect of the 5R(5A) Alien Chromosome Substitution on the Growth Habit and Winter Hardiness of Wheat

The growth habit, ear emergence time, and frost tolerance of wheat/rye substitution lines have been studied in cultivars Rang and Mironovskaya Krupnozernaya whose chromosome 5A is substituted with chromosome 5R of Onkhoyskaya rye. Hybrid analysis has demonstrated that the spring habit of the recipient cultivars Rang and Mironovskaya Krupnozernaya is controlled by dominant gene Vrn-A1 located in chromosome 5A. Onokhoyskaya rye has a dominant gene for the spring habit (Sp1) located in chromosome 5R. It has been found that the resultant 5R(5A) alien-substitution lines have a winter type of development and ears do not emerge during summer in plants sown in spring. The change in growth habit has been shown to be related to the absence of the rye Sp1 gene expression in the substitution lines. The winter hardiness of winter 5R(5A) alien-substitution lines has been studied under the environmental conditions of Novosibirsk. Testing the lines in the first winter demonstrated that their winter survival is 20–27%. The possible presence of the frost resistance gene homeoallelic to the known genes Fr1 and Fr2 of the common wheat located on chromosomes 5A and 5D, respectively, is discussed.     

Influence of Temperature on the Virulence of Two Races of Meloidogyne chitwoodi on Wheat and Barley

Races of the Columbia root-knot nematode, Meloidogyne chitzooodi, from Idaho (R1) and Utah (R2) suppressed (P < 0.05) tillering of Dusty winter wheat, Fielder spring wheat, Luther winter barley, and Steptoe spring barley at 15-30 C. Nematode inoculum density was negatively correlated with tillering (r = -0.79). Inoculum densities of both nematode races were negatively correlated with heads per plant (r = -0.83), head length (r = -0.87), and head dry weight (r = 0.73) of Fielder spring wheat and Steptoe spring barley at all temperatures; the greatest growth restrictions occurred at Pi 20 eggs/cm³ soil. Both nematode races were most damaging at 25-30 C. Fielder spring wheat and Steptoe spring barley inoculated with R2 produced fewer heads than R1 when inoculated at 15 C, whereas the same cultivars inoculated with R1 produced fewer heads than R2 at 30 C. No differences were observed between root growth of winter and spring wheat or between winter and spring barley. Nematode reproduction was positively correlated to temperature (r = 0.87) and negatively correlated with inoculum density (r = -0.86). Reproductive rates were greatest with Pi = 2 eggs/cm³ soil at 25 C and lowest with Pi = 20 eggs/cm³ soil at 15 C for both nematode races.     

The relationship between vernalization requirement and frost tolerance in substitution lines of wheat

Two sets of wheat (Triticum aestivum L.) substitution lines for the homoeologous group 5 chromosomes, 5A, 5B and 5D, carrying vernalization genes (Vrn-A1, Vrn-B1, Vrn-D1) were used to study the relationship between vernalization requirement and winter survival, with respect to the induction and maintenance of frost tolerance. Substitution lines carrying dominant Vrn loci substituted from the spring cultivars Zlatka (5A), Chinese Spring (5D) and the alternative cultivar eská Pesívka (5B) into three different winter wheat backgrounds, Vala, Koútka and Zdar, showed lower winter survival by 20, 36, and 41 % for substitutions of 5B, 5A and 5D, respectively, compared to the original winter cultivars. Reciprocal substitution lines between two winter cultivars Mironovskaya 808 and Bezostaya 1 carrying different recessive alleles, vrn-A1, vrn-B1, vrn-D1, did not exhibit a modified induction of frost tolerance, but the duration of good frost tolerance, as well as the ability to survive the whole winter, was changed. In accordance with the model suggesting that genes for vernalization act as a master switch regulating the duration of frost tolerance, substitutions of homoeologous group 5 chromosomes induced, at first, frost tolerance at a level equal to the parental cultivar, and then, relative to the different extent of saturation of vernalization requirement, they gradually lost both frost tolerance and their ability to re-induce significant frost tolerance with a drop in temperature following warm periods in the winter.     

New data on the distribution of hybrid necrosis genes in winter bread wheat (<Emphasis Type="Italic">Triticum aestivum</Emphasis> L.) cultivars

Hybrid necrosis genotypes have been identified in 125 Russian cultivars of winter bread wheat. More than half of them (56%) carry the Ne2 gene (genotype ne1ne1Ne2Ne2); others are free of necrosis genes (genotype ne1ne1ne2ne2). The possible causes of the increase in the Ne2 allele frequency and the loss of the Ne1Ne1ne2ne2 genotype in modern Russian cultivars of winter wheat are discussed. The principal component method has been used to compare the structures of the genetic diversity of cultivars differing in the hybrid necrosis genotype. It has been found that the Ne2 allele in winter wheat cultivars from northern Russia has originated from the cultivar Mironovskaya 808, whereas the cultivar Bezostaya 1 is not a source of this gene. In cultivars from southern Russia, the presence of the Ne2 allele is also mainly accounted for by the use of Mironovskaya 808 wheat in their breeding. The recessive genotype is explained by the presence of descendants of the cultivar Odesskaya 16 in the pedigrees of southern Russian winter wheats. The genetic relationship of cultivars with identical and different necrosis genotypes has been analyzed in nine regions of the Russian Federation.     

Genetics of Heading Time in Wheat (TRITICUM AESTIVUM L.). II. the Inheritance of Vernalization Response

The inheritance of vernalization response was studied in crosses involving four spring wheats (Sonora 64 (S), Pitic 62 (P), Justin (J) and Thatcher (T)) and three winter wheats (Blackhull (B), Early Blackhull (E) and Extra Early Blackhull (EE)).—All winter cultivars were highly responsive to vernalization, and Pitic 62 was the only spring cultivar whose time to heading was significantly accelerated following cold treatments. When vernalized and grown under long days, spring and winter cultivars became comparable in their heading response, indicating that cold requirement is the major attribute differentiating the heading behavior of true spring and true winter wheats.—Inheritance of growth habit in the F₁ generation of a five-parent diallel cross showed dominance of the spring character in all spring x winter crosses. Depending on the cross, one or two duplicate major genes governing growth habit were detected in F₂, F₃ and backcross generations grown in the field under long days in the absence of vernalizing temperatures. In some spring x winter crosses most of the variation in heading time among spring segregates could be attributed to the effects of major genes conditioning growth habit. In other crosses the heading patterns appeared more complex, indicating that genes with smaller effects are also involved in the control of heading response under spring or summer environments.—Evidence was presented supporting the hypothesis that the cultivar Pitic 62 carries a different allele at one of the two major loci governing its spring habit. This allele was associated with some response to vernalization and acted as a dominant gene determining earliness under low temperature vernalization, but as a partially recessive gene determining lateness in the absence of vernalizing temperatures. Genotypes were assigned to five cultivars as follows: S, CC DD; P, CC D'D'; J, cc DD; B and EE, cc dd.—The presence of major and minor genes and of multiple alleles governing response to photoperiod and vernalization was discussed in relation to the genetic manipulation of the heading response and to breeding wheat cultivars with specific or broad adaptation.     

Primary and secondary metabolism of winter wheat under cold hardening and treatment with antioxidants

The content of saccharides and phenolic compounds (including flavonoids and lignin) and the activity of L-phenylalanine ammonia-lyase (PAL, EC 4.3.1.5) were determined in leaves and tillering nodes of winter wheat Triticum aestivum L.) cultivars Inna and Moskovskaya 39, differing in the level of frost resistance. These parameters were determined in three groups of plants—control, hardened, and treated with synthetic antioxidants (ambiol and amerol 2000). Cold hardening increased accumulation of primary and secondary metabolites in tissues but decreased the enzyme activity. Treatment with antioxidants also increased the content of saccharides and phenolic compounds (primarily flavonoids) and PAL activity. These changes were more pronounced in cultivar Inna, which is less frost resistant than Moskovskaya 39.     

Phenolic compounds (hydroxycinnamic acids,flavan-3-ols,flavonols) profile in fruit of Italian peach varieties

Interest in phenolic compounds of fruit is growing due to their positive effects on reducing the risk of cardiovascular and carcinogen diseases. The role of the flesh colour, of the tissue (exocarp or mesocarp) and of the cultivar on the content of phenolic compounds (hydroxycinnamic acids, flavan-3-ols, flavonols) was evaluated in peach, Prunus persica (L.) Batsch, with a HPLC-DAD analysis, on 10 varieties deriving from the Italian breeding programmes, never previously characterized by this approach. The flavan-3-ols (catechin, epicatechin and procyanidin B1) were the most abundant class of phenolic compounds in peach cultivars analysed. Among hydroxycinnamic acids, neochlorogenic and chlorogenic acids were also identified and measured in the peach cultivars analysed. Quercetin-3-O-rutinoside was the only flavonol found in the exocarp of all the cultivars evaluated, but in the mesocarp of only some cultivars. Content of phenolic compounds was confirmed to be strongly dependent on the cultivar and, in general, the content was significantly higher in exocarp than in mesocarp. An overall significant difference in phenolic compounds as associated with flesh colour was not observed.     

Impact of intercropping aphid-resistant wheat cultivars withoilseed rape on wheat aphid (Sitobion avenae) and its natural enemies

The effects of intercropping of wheat cultivars and oilseed rape on the densities of wheat aphid, Sitobion avenae, and their arthropod natural enemies were evaluated. Three winter wheat cultivars with different resistant levels to S. avenae were used: ‘KOK’ (high resistance), ‘Xiaobaidongmai’ (low resistance) and ‘Hongmanghong’ (susceptible). The results showed that the densities of S. avenae were significantly higher on the monoculture pattern than on either the 8-2 intercropping pattern (eight rows of wheat with two rows of oilseed rape) or the 8-4 intercropping pattern (eight rows of wheat with four rows of oilseed rape). The mean number of predators and the mummy rates of S. avenae were significantly higher in two intercropping patterns than those in the monoculture pattern. The densities of S. avenae, ladybeetles, and mummy rate of S. avenae were significantly different among different wheat cultivars. The highest densities of S. avenae and ladybeetles were found on wheat cultivar Hongmanghong. The lowest densities of S. avenae associated with high mummy rate of S. avenae were found on wheat cultivar Xiaobaidongmai. The results showed that wheat-oilseed rape intercropping conserved more predators and parasitoids than in wheat monoculture fields, and partial resistance of wheat cultivar Xiaobaidongmai had complementary or even synergistic effects on parasitoid of S. avenae.     

Cold-induced changes of enzymes,proline, carbohydrates,and chlorophyll in wheat

Quantitative changes in total leaf soluble proteins, proline, carbohydrate content, chlorophyll fluorescence, guaiacol peroxidase (POD) and catalase (CAT) activities were determined in a less cold-hardy (LCH) spring cv. Kohdasht (LT₅₀ = −6°C), a semi cold-hardy (SCH) facultative cv. Azar 2 (LT₅₀ = −15°C), and a cold-hardy (CH) winter cv. Norstar (LT₅₀ = −26°C) of wheat (Triticum aestivum L.) exposed to 4°C for 9 weeks. Seedlings were grown in a controlled growth room for 14 days at 20°C and then transferred to 4°C (experimental day 0) for 63 days (cold treatment); otherwise they were maintained continuously at 20°C (control treatment). The samples were harvested 0, 2, 21, 28, 42, and 63 days after exposure to 4°C. The results showed significant low temperature (LT)-induced accumulation of total soluble proteins, proline, and carbohydrates and elevation in activities of CAT and POD in leaves of SCH and CH winter cultivars rather than in LCH spring cultivar. In contrast, the chlorophyll fluorescence (F _v/F _m) declined during LT treatment irrespective of cultivar. The results suggest that developmental traits such as vernalization requirement of wheat affects on cold-tolerance expression system of plants.     

不同小麦品种对低温胁迫的反应及抗冻性评价

以济麦19、济麦21、济南17等15个冬小麦品种为材料,对其在低温胁迫条件下功能叶和叶鞘超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性、过氧化氢酶(CAT)活性、丙二醛(MDA)含量与可溶性蛋白含量等生理指标进行测定,以功能叶各项指标的抗冻系数作为衡量抗冻性的指标,利用主成分分析、聚类分析对其抗冻性进行综合评价。低温胁迫条件下,不同冬小麦品种起身拔节期功能叶和叶鞘中SOD活性、POD活性和CAT活性均不同程度地上升,MDA含量和可溶性蛋白含量均下降。通过主成分分析和聚类分析,将15个冬小麦品种划分为3类:济麦19、山农8355属强抗冻类型;山农664、泰山9818、济麦21、济麦22、烟农24、烟农19、烟农21、汶农6号、鲁麦21、济南17属中度抗冻类型;其余3个品种(泰山23、聊麦18、临麦2号)属弱抗冻类型。     

In vitro microspore reaction of different German wheat cultivars

Summary The in vitro microspore androgenesis reaction of 25 commercial German spring (including 4 Triticum durum) and 50 winter wheat cultivars was investigated. Tremendous genotypical differences were found in microspore response. The best-responding winter wheat cultivai, Florida, is characterized by the presence of a 1B/1R wheat-rye translocation chromosome. The significance of this finding and other genetic systems for future use of haploids in plant breeding is discussed.     

Feedback-limited photosynthesis and regulation of sucrose-starch accumulation during cold acclimation and low-temperature stress in a spring and winter wheat

Regulation of sucrose-starch accumulation and its effect on CO₂ gas exchange and electron transport were studied in low-temperature-stressed and cold-acclimated spring (Katepwa) and winter (Monopol) cultivars of wheat (Triticum aestivum L.). Low-temperature stress of either the spring or winter cultivar was associated with feedback-limited photosynthesis as indicated by a 50–60% reduction in CO₂ assimilation rates, twofold lower ATP/ADP ratio, and threefold lower electron transport rate than 20°C-grown control plants. However, no limitations were evident at the level of ribulose-1,5-bisphosphate carboxylase-oxygenase (Rubisco) in low-temperature-stressed plants. Cold acclimation of the spring cultivar resulted in similar feedback-limited photosynthesis observed during low-temperature stress. In contrast, cold acclimation of the winter cultivar resulted in an adjustment of CO₂ assimilation rates to that of control plants. However, we show, for the first time, that this capacity to adjust CO₂ assimilation still appeared to be associated with limited triose phosphate utilisation, a twofold lower ATP/ADP ratio, a reduction in electron transport rates but no restriction at the level of Rubisco compared to controls grown at 20°C. Thus, contrary to previous suggestions, we conclude that cold-acclimated Monopol appears to exhibit feedback limitations at the level of electron transport characteristic of cold-stressed plants despite the maintenance of high rates of CO₂ assimilation. Furthermore, the differential capacity of the winter cultivar to adjust CO₂ assimilation rates was associated with higher levels of sucrose accumulation and a threefold higher sucrose-phosphate synthase activity despite an apparent limitation in triose phosphate utilisation.Abbreviations AGPase ADP-glucose pyrophosphorylase - FBPase fructose-1,6-bisphosphatase - Fru 6-P fructose 6-phosphate - Fru 1,6-BP fructose 1,6-bisphosphate - Glc 6-P glucose 6-phosphate - PGA 3-phosphoglyceric acid - Rubisco ribulose-1,5-bisphosphate carboxylase-oxygenase - RuBP ribulose 1,5-bisphosphate - SPS sucrose-phosphate synthase - Triose-P triose phosphate