GrainGenes

ITEMS FROM HUNGARY

 

AGRICULTURAL RESEARCH INSTITUTE OF THE HUNGARIAN ACADEMY OF SCIENCES

Martonvásár, H-2462, Brunsvik str. 2, Hungary.

 

Department of Wheat Breeding.

Z. Bedö, L. Szunics, L. Láng, Lu. Szunics, O. Veisz, I. Karsai, Gy. Vida, and P. Szücs.

Wheat season. The weather in 1997 was quite changeable. Wheat received precipitation in the critical period, thus fairly good, but lower than expected, yields were harvested. Because of wet weather at harvest, yields were lower and baking quality and seed value deteriorated. Wheat started germinating in the ear in several locations.

Breeding. The registration of three wheat cultivars is expected in the spring of 1998 on the basis of results from the state variety trials .

Mv Summa (Mv 04-95) is an early maturing, soft, red, awnless wheat (pedigree: GK 36-83 / SO1586 // Mv 17). Characterized by excellent yield potential and medium baking quality, Mv Summa has excellent frost and lodging resistance, medium resistance to powdery mildew, and moderate resistance to leaf rust and stem rust. Mv Summa is BYDV resistant.

Mv Magvas (Mv 06-95) is a hard red wheat. Mv Magvas matures 2­3 days later than Mv Summa. The cultivar was selected from three excellent quality parents (F 26-70 / Macvanka 2 // Mv MA) and has higher than average gluten content and very good rheological characteristics. The awned genotype is frost resistant and has good lodging resistance. Mv Magvas is moderately susceptible to powdery mildew, moderately resistant to stem rust, and resistant to leaf rust.

Mv Mezöföld (Mv 09-95) is a mid-season maturing, awnless wheat from a cross made from two of the most successful Hungarian wheat varieties of the 1980s, the early maturing GK Öthalom and the later Mv 15. The vegetative period and quality are intermediate between those of the two parents, but the yield potential and resistance of Mv Mezöföld are significantly better. Quality is average. Mv Mezöföld has good resistance to frost, powdery mildew, and stem rust and medium resistance to leaf rust.

Molecular markers. Nineteen DH lines from the 'Dicktoo / Morex' mapping population were phenotyped in controlled environment photoperiod experiments to determine the role of two previously detected QTLs on developmental patterns of barley. The QTLs are hypothesized to represent the effects of the Ppd and Sh2 loci on chromosomes 2 (2H) and 7 (5H), respectively. Alleles at the Ppd locus are found to vary in response to photoperiod duration. Vernalization had some effect on alleles at both loci. The presence of early- and late-flowering transgressive segregants in this mapping population can be explained by interactions between the Ppd and Sh2 loci. The Ppd and Sh2 loci are hypothesized to be homoeologous with the Ppd and Vrn1 loci of wheat.

A DH population of 100 lines was developed from the cross 'Dicktoo / Kompolti korai', two winter barley cultivars. A series of experiments evaluated the vernalization requirement and heading date of the lines under different light regimes and their frost tolerance in artificial freezing tests. A DNA marker-based linkage map was initiated at the same time. To quicken map preparation and to fill in gaps, STS and RAPD primers in addition to RFLPs also were screened in the two parents. Application of the polymorphic probes and markers for the whole population has been done recently.

A DH population of 100 lines also was developed from the cross 'Dicktoo / Plaisant', two winter barley cultivars. A series of experiments evaluated the heading date of the lines under 8- and 24-hour daylength and their frost tolerance in artificial freezing tests. A partial map of the 'Dicktoo / Plaisant' population was begun in those chromosome regions that proved to have significant roles in the 'Dicktoo / Morex' population in determining winter hardiness-related traits. A QTL peak for frost tolerance was located on chromosome 5 close to the Sh2 locus, in addition to the one already described on chromosome 7. A smaller QTL for heading date of vernalized plants under 8 hour daylength also appeared in this region of chromosome 5.

Biochemical and molecular markers were used to characterize the breadmaking quality of a population of the old wheat cultivar Bánkúti 1201. This cultivar and its derivatives consist of heterogeneous populations and represent special types. Their breadmaking quality is good, although they possess 2+12 HMW-glutenin subunit encoding genes on chromosome 1D. The population of Bánkúti 1201 was separated into lines possessing five different HMW-glutenin subunit compositions. Using molecular markers (a primer pair specific for the upstream region of the 1Dx5 gene) to test the population of Bánkúti 1201 confirmed that the population is heterogeneous, having three different fragment types. The majority of the Bánkúti 1201 lines possessed a fragment measuring approximately 1,300 bp apparently specific for this cultivar. These genotypes had better technological properties than those with PCR patterns similar to Chinese Spring.

Tissue culture. The effect of carbohydrate content on anther culture efficiency of hexaploid winter triticale was studied. The maltose concentration in the induction medium significantly influenced the anther culture efficiency, but the genotype and the 'genotype x maltose' interactions also were highly significant factors. The application of 0.21 M or 0.26 M maltose resulted in higher embryo induction in most cases. The best carbohydrate source in the regeneration medium (sucrose vs. maltose) also was genotype dependent. Of the three basal regeneration media, those based on 190-2 and MN6 proved to be more efficient with a strong genotype dependence, whereas all the triticale cultivars gave the poorest results on MS-based regeneration medium. Among the triticale varieties, Moniko and TF12 possessed the highest green-plant induction and showed the largest change in this frequency as the result of different treatments. The reactions of the other cultivars, with extremely poor green-plant regeneration (less than 5 green plants/100 anthers cultured), were not altered significantly.

Disease studies. A moderate leaf rust epidemic in Hungary was reported this year. One reason for the epidemic is that a substantial part of the cultivars grown have the resistance genes Lr3 and Lr26. The pathogen population is virulent to these two genes. Provocation field trials showed that the resistance genes Lr9, Lr19, Lr23, Lr24, Lr25, Lr27, Lr33, and Lr37 provide adequate protection against leaf rust.

No stem rust epidemic has occurred for many years, mainly because of the Sr31 and Sr36 resistance genes present in the cultivars that provide very good biological protection. At the same time, the pathogen is avirulent to the following genes: Sr9b, Sr11, Sr21, Sr24, and Sr37.

Wheat powdery mildew infection appeared to be less than average. The known major resistance genes do not provide adequate protection, because the pathogen is virulent to them. The only exception is Khapli (Pm4a); no pathotypes are virulent to it. Of the isolates, 20.47 % are resistant to the resistance gene Pm1+2+9 (Normandie), 22.85 % to Pm2+Mld (Halle st. 13471), and 32.38 % to Pm4b (TP 315/2). In our glasshouse experiments, 23 races were identified using the test assortment compiled by Nover. The prevalent races and their frequencies are 90 (18.58 %), 51 (16.67 %), 72 (11.43 %), 70 (7.62 %), and 63 (7.15%). The number of virulence genes of the pathogen population is 5.04.

Snow mold appeared in several places in the country, and a severe ear epidemic caused by Fusarium spp. arose. The prevalent cultivars are all sensitive; the only differences are in degree of susceptibility.

The bunt susceptibility of the wheat cultivars also was investigated. Although no resistance breeding is conducted in this field, the registered cultivars are generally susciptible. Among the known genotypes with Bt genes, the resistant ones are Bt5, Bt6, Bt8, Bt9, Bt10, Bt11, and Bt12.

The majority of the recent cultivars bred at Martonvásár have good resistance to powdery mildew (Mv Pálma, Mv Vilma, Mv Magdaléna, Mv Mezöföld) and leaf rust (Mv Pálma, Mv Vilma, Mv Magdaléna, Mv 25, Mv Magvas), and nearly all of them have excellent resistance to stem rust. All the cultivars have average susceptibility to ear Fusarium and bunt. The complex resistance or slight susceptibility of our cultivars provides adequate protection to several pathogens at the same time. Thus, when these cultivars are grown, the costs of production are insignificant for chemical crop protection, and chemical contamination of the environment is not a repercussion.

The phytotron facilities provide good conditions for abiotic stress resistance research. Under controlled conditions, the effects of atmospheric CO2 concentration, spectral light composition, freezing temperature, and soil humidity on the hardiness and frost resistance of winter cereals were determined. Frost resistance of winter wheat, rye, and triticale cultivars grown at a concentration of 700 mol/mol atmospheric CO2 was better than that of those raised at the normal atmospheric CO2 concentration (350 mol/mol CO2). Increasing the CO2 level had a favorable effect on the hardening process. Consequently, the average survival percentage was significantly better than that of the control plants. For all cultivars, the higher the CO2 concentration, the greater the increase in leaf area. The dry mass also increased for the majority of the cultivars.

The cultivars responded in different ways to freezing at low temperature for an extended period of time. Some of the studied varieties withstood the cold better at a higher freezing temperature (-12 C) for a longer time (72 hours) than at a lower temperature (- 18 C) for a shorter time. Other cultivars behaved contrary to this. An increase in soil humidity increased the percent kill of the cultivars with good frost resistance only slightly, whereas that of the cultivars with moderate and poor frost resistance increased significantly.

Winter wheat, rye, triticale, durum wheat, barley, and oat cultivaras were used to investigate the early vigor and frost resistance of plants raised under different light spectra. No reliable differences were noted in the frost resistance of cereals or between different cultivars within a species, when grown with light sources of different spectra but identical photon flux density. The leaf area (measured in the sixth week of growth) and the aboveground biomass) of four of the studied winter wheats were significantly higher for the plants raised under metal halogen lamps. No significant differences occurred for the other four cutlivars. The results reveal that photon flux density plays a decisive role in the hardening process of winter cereals, whereas various phenological characteristics also are influenced by the spectral energy distribution of the light source.

 

Department of Genetics.

J. Sutka, G. Galiba, M. Molnár-Láng, G. Kocsy, B. Köszegi, G. Linc, and A. Vágújfalvi.

Frost tolerance. A mapping population consisting of a recombinant substitution line population developed from the cross between Chinese Spring and a single-chromosome substitution line for the Cheyenne 5D in Chinese Spring (CS­CNN DS5D). Chinese Spring is sensitive to frost, and the substitution line is relatively resistant. The frost resistance of each of the recombinant subtitution lines and their parents was tested using the facilities of the Martonvásár Phytotron. Because chromosome 5D is known to control flowering time through the vernalization response locus Vrn3, the flowering time of each line was characterized in a growth chamber under a regime of 16 h day­8 h night at temperatures of 22 and l5°C, respectively.

RFLPs and AFLPs were used to map Vrn3 and Fr2 on the long arm of 5D. First, RFLP probes known to map to chromosomes of homoeologous group 5 of wheat were tested for polymorphism between the parents of the mapping population of Chinese Spring and CS­CNN DS5D. A range of genomic and cDNA clones from wheat, barley, and oats were used. However, only two probes, WG232 and PSR567, both located on the long arm of the group 5 chromosomes, revealed polymorphisms suitable for mapping. Both probes were hybridized to each of the recombinant lines for genotypic classification. Because of the paucity of RFLPs, AFLPs also were used on the recombinants. Seven primer combinations were used and together revealed eight scorable polymorphisms. Based on this marker information, associations between the markers and the data for flowering time and frost tolerance were tested using ANOVA and QTL mapping. The two RFLPs and four of the AFLPs showed a significant association, confirming the location of Vrn3 and Fr2 on the long arm of 5D. A map of the long arm of chromosome 5D was constructed based on these analyses for the population containing Vrn3 and Fr2, using the two RFLPs and three of the AFLPs. This map confirms that Vrn3 and Fr2 are linked, but separate loci, and that Fr2 appears genetically to be more distant from Vrn3 than Vrn1 is from Fr1. This work was done in cooperation with Dr. J. Snape (John Innes Centre, Norwich, U.K.).

Glutathione reductase and thioredoxin h are both NADP-dependent redox enzymes with different physiological roles. Glutathione and glutathione reductase are important components of the antioxidant system. Glutathione reductase reduces oxidized glutathione, an extremely important reaction, because only reduced glutathione is active. Glutathione takes part in the detoxification of hydrogen peroxide in the ascorbate-glutathione reaction pathway.

Thioredoxin h (one of the enzymes belonging to the plant thioredoxin system) specifically decomposes the intramolecular disulphide (- SS -) bonds of the majority of water-soluble and water-insoluble proteins. The reduction of these bonds naturally causes a dramatic change in the properties of the proteins. A reduction in the activity of protease and amylase inhibitors occurs, leading to the activation of hydrolytic enzymes. No study has yet been published on whether thioredoxin h plays any role in stress adaptation processes. This is the first report of a probable role of this type.

We examined the frost-sensitive spring wheat cultivar Chinese Spring, the frost-sensitive species T. spelta (Tsp), the frost-resistant winter wheat Cheyenne, the chromosome substitution lines CS­Tsp DS5A and CS­CNN DS5A, and recombinant lines created from their intercrosses. Chinese Spring deletion lines and lines nullicomic for 5A also were used. Some of the plants were cold-hardened for various periods, whereas others were grown hydroponically and either abscisic acid (40 mg/l) or polyethylene glycol (PEG 4000 21 %) was added to the nutrient solution for 6 days. After the treatments, the glutathione reductase enzyme activity in the stems and leaves and presence of thioredoxin h were measured. Both enzymes were identified by means of Western hybridization (using polyclonal antibodies).

The glutathione reductase activity was changed only slightly as the result of the treatments. An increase in the activity in sensitive genotypes was observed after several weeks of cold hardening. The results of Western hybridization suggest that specific isoenzymes are activated or inhibited by various treatments. The individual treatments led to genotype-dependent, specific, thioredoxin h isoenzyme patterns. A correlation between frost resistance and increases in the concentration of certain thioredoxin isoenzymes is assumed.

Wheat­barley translocations. Wheat-barley translocations were observed among the selfed seeds from some BC2 plants originating from in vitro-regenerated 'Chinese Spring/Betzes' hybrids. Three different kinds of translocations were observed by GISH among the BC2 progenies of the regenerated plants. In selfed progenies of BC2 plants originating from in vitro-regenerated hybrids, a centric fusion was observed between a wheat and a barley chromosome arm. Three entire barley chromosomes and a telocentric could be seen in the same preparation, in addition to the translocated chromosome. The same Robertsonian wheat-barley translocation was observed in other selfed progenies from the same BC2 plant.

Simultaneously, using a backcross program involving the Chinese Spring-Betzes hybrids previously produced, several attempts were made to produce new hybrid combinations of wheat and barley. Two wheat genotypes were used mainly as the maternal plants: Chinese Spring and the winter wheat line Martonvásári 9 kr1 (MV9 kr1). The barley cultivars tested for hybrid production were Betzes, Martonvásári 50, Martonvásári 37, Martonvásári 38, Osnova, Manas, Igri, Kompolti korai, Attila, Botond, Kaliforniai Mariont, Duet, P-284-90, Intro, Swift, NRPB, and Trasco.

GISH analysis of Ae. cylindrica. This work was made in coöperation with Dr. B. Friebe (Kansas State University, Manhattan, USA). Recently detailed karyotypic data, including C-banding patterns and the distribution of four repetitive DNA sequences, have been reported for all the diploid Aegilops species (Badaeva et al. Genome 39:1150-1158 1996). We analyzed the polyploid Aegilops species with the aid of GISH. Aegilops cylindrica, genomically DCDCCCCC, was chosen for the first in situ hybridization analysis. The genomic constitution of Ae. cylindrica was determined earlier in studies that identified the diploid species Ae. caudata, genomically CC, as the donor of the C genome and Ae. tauschii, genomically DD, as the donor of the DC genome of Ae. cylindrica. The cytoplasm of Ae. cylindrica was contributed by Ae. tauschii.

Total DNA of Ae. caudata was labeled with fluorogreen by nick translation, and unlabeled DNA of Ae. tauschii was added as the blocking DNA. This probe was used for genomic in situ hybridization on root tip preparations of Ae. cylindrica. The chromosomes of the C genome showed bright fluorescence, whereas the chromosomes of the D genome remained unlabeled. Five different Ae. cylindrica accessions were analyzed. GISH revealed the presence of reciprocal intergenomic translocations in three accessions. These translocations could have arisen as the result of different environments.

Vrn3 and Fr2 are linked, but separate loci, and that Fr2 appears genetically to be more distant from Vrn3 than Vrn1 is from Fr1. This work was done in cooperation with Dr. J. Snape (John Innes Centre, Norwich, U.K.).

 

Physiology.

E. Páldi, T. Janda, and G. Szalai.

In recent years, special wheat lines have been used to make a detailed study on the quantitative and qualitative changes taking place in the rRNA maturation process as the result of cold treatment, with special regard to frost tolerance. By adapting a method of nucleic acid to wheat, these results have made it possible to draw conclusions on the frost tolerance of given genotypes. A close correlation seems to exist between the LT50 value of wheat cultivars and the quantity of 1.4 million dalton (MD) rRNA precursor. In order to prove the reliability and applicability of the method, experiments aimed at the elaboration of a selection method were set up on 16 winter and spring wheat cultivars and lines with different degrees of frost tolerance.

The evidence of a correlation between the quantity of 1.4 MD rRNA precursor and frost tolerance was based on results obtained when analyzing the rRNA maturation process. The 1.4 MD rRNA precursor was chosen for the examination, because it is stable and easily demonstrated. When winter wheats with good frost tolerance were incubated at 1°C with 32P, no 1.4 MD rRNA precursor was found. As the degree of frost tolerance or LT50 decreased, the quantity of the precursor increased. The change was the most pronounced in spring wheats with no frost tolerance. A close positive correlation was found between the frost tolerance of the given wheats, characterized by the LT50 values, and the quantity of 1.4 MD rRNA precursor.

An increase in the quantity of the 1.4 MD rRNA precursor indicates primarily an inhibition in the maturation processes of the ribosomes, especially in the final nuclease step. In nonfrost-hardy cultivars, an increase in the rRNA precursor level indicates that the disturbances caused by low temperatures do not act primarily through 32P uptake by the seedlings but rather by inhibition of the maturation processes of the ribosomes. The simplest interpretation of the results is to assume that frost-hardy wheats are characterized generally by no disturbance in rRNA synthesis and the maturation of the ribosomes at low temperatures. The undisturbed process is manifested as a greater synthesis of the heavy (1.3 MD) and light (0.7 MD) stable cytoplasmic rRNAs. The relatively harmonious nature of this metabolism is destroyed as the frost hardiness of the cultivars decreases and is expressed in a higher quantity of the 1.4 MD rRNA precursor synthesized.

 

Current activities in wheat research at the Department of Plant Cell Biology and Physiology.

B. Barnabás, E. Páldi, G. Kovács, T. Janda, I. Takács, G. Szalai, Z. Pónya, I. Tímár, G. I. Paluska, M. Vértényi, and P. Finy

Comparative studies on the development of male and female gametophyte in wheat. The in planta and in vitro development of the female and male gametophytes of three Triticum species was traced from meiosis until the development of mature pollen or embryo sac. The dynamics of differentiation in the male gametophyte was not influenced by different ploidy levels up to the trinuclear stage. The maturation process of differentiated haploid male gametophytes resulted in the shedding of mature pollen from the anthers proceeds most rapidly in the hexaploid species. The development of the initial microspore slowed in vitro compared to the control; they remained longer in the uninucleate stage, which delayed the first pollen mitosis. No substantial differences among the three species in the dynamics of in vitro pollen development were noted. The uninucleate microspore developed into a functional tricellular pollen grain within a week in all cases. However, significant differences occurred in the length of the various developmental stages of the male and female gametophytes under in vitro and natural conditions. The 7-celled female gametophyte developed far more rapidly than the male gametophyte, which means that the mitotic divisions leading to the differentiation of male and female gametophytes were not synchronised within the plants. In species with lower ploidy levels, macrosporogenesis and the development of the 7-celled embryo sac was completed 2 days later than in hexaploid species. Differing ploidy levels also influenced the size of the embryo sac. The embryo sacs achieved their maximum dimensions 2-3 days prior to male gametophyte maturation. These observations raise several questions as to when gametophytes can be regarded as functionally mature and which phase of gametophytic development is most suitable for cell manipulation.

Selection for frost tolerance in anther culture. The use of anther culture to screen for frost tolerance and to selcet mutants at the haploid level is still limited in wheat. However, in vitro haploid and dihaploid induction in wheat may provide a useful tool for the selection of frost resistance, because the existing or induced tolerance in the microspore or haploid embryo population can be screened easily and fixed in a homozygotic form. The possibility of developing frost-resistant lines by exposing somatic tissues to subzero temperatures after hardening was reported earlier by several research groups, but untill now, no data on the use of haploid cultures were available. In our present research, the possibility of selecting frost-tolerant haploid embryoids and the regeneration of fertile DH lines from these selected embryos was studied. In the course of the experiments, anthers from the F1 hybrids of 'frost tolerant / sensitive' cultivars, their reciprocal hybrids, and their parents were cultured on a solidified induction medium. After 5 weeks of induction in the dark, haploid embryos were harvested and cold treated under controlled phytotronic conditions. The hardened embryos were frozen at - 15 C. After freezing, plants were regenerated using the traditional regeneration method, and the regenerants were grown till maturity under artificial conditions. Fertile regenerants were self pollinated. The progeny generation was tested using the usual frost-resistance testing method, and the results of the freezing test suggested that about 80 % of the DH lines obtained were frost tolerant. According to the data obtained in our experiment, we can conclude that the haploid selection method provides a strong possibility of producing frost-tolerant DH lines from crosses between frost-tolerant and sensitive genotypes in a relatively short time. Some of the DH lines regenerated from the frozen embryos of the sensitive parent showed relatively high viability in the freezing tests. These results suggest the possibility of selecting for frost-tolerant mutants from a haploid culture.

 

Publications.

Barnabás B, Tímár I, and Pónya Z. 1997. In planta and in vivo differentiation on the female gametophytes of various Triticum species with different ploidy levels and genome compositions. Növénytermelés 46:125-131.

Bedõ Z, Vida Gy, Láng L, and Karsai I. 1997. Breeding for breadmaking quality using old Hungarian wheat varieties. In: Wheat: Prospects for global improvement. Proc 5th Inter Wheat Conf, 10­14 June, 1996, Ankara, Turkey. pp. 245-248.

Galiba G, Kerepesi I, Snape JW, and Sutka J. 1997. Location of a gene regulating cold-induced carbohydrate production on chromosome 5A of wheat. Theor Appl Genet 95:265-270.

Galiba G, Nagy Z, Janda T, Szente K, Csintalan Zs, Tuberosa R, Monneveux P, and Coumans M. 1997. Heat stress-induced differential alterations in the photosynthesis, membrane thermostability and biomass production of bread and durum wheat varieties. Acta Agron Hung 45:1-15.

Galiba G, Kerepesi I, Snape JW, and Sutka J. 1997. Mapping of genes related to cold hardiness in wheat. In: Proc Inter Symp Cereal Adaptation to Low Temperature Stress (Bedõ Z, Sutka J, Tischner T, and Veisz O eds), Martonvásár Hungary. pp. 155-161.

Harnos N, Veisz O, Mészáros K, and Tischner T. 1997. Effect of CO2 concentration on the development of young winter cereals in the phytotron. In: Proc Inter Symp Cereal Adaptation to Low Temperature Stress (Bedõ Z, Sutka J, Tischner T, and Veisz O eds), Martonvásár Hungary. pp. 300-302.

Hayes P, Chen T, Powell W, Bedõ Z, Karsai I, and Mészáros K. 1997. Dissecting the components of winter hardiness in barley. Acta Agron Hung 45(3):241-246.

Hayes PM, Chen FQ, Corey A, Bedõ Z, and Karsai I. 1997. The Dicktoo x Morex population: a model for dissecting the components of winter hardiness. In: Plant Cold Hardiness (Li PH and Chen T eds). Plenum, New York, USA. pp. 77-87.

Karsai I and Bedõ Z. 1997. Effect of carbohydrate content on the embryoid and plant production in triticale anther culture. Cereal Res Commun 25:109-116.

Karsai I and Bedõ Z. 1997. Relationship between anther culture response and aluminium tolerance in wheat (Triticum aestivum L.). In: Wheat: Prospects for global improvement. Proc 5th Inter Wheat Conf, 10­14 June, 1996, Ankara, Turkey. 315-318.

Karsai I, Mészáros K, Bedõ Z, Hayes PM, Pan A, and Chen F. 1997. Genetic analysis of the components of winterhardiness in barley (Hordeum vulgare L.). Acta Biol Hung 48(1):67-76.

Karsai I, Mészáros K, Hayes PM, and Bedõ Z. 1997. QTL study of winter hardines-related traits in a double haploid population of Dicktoo x Pleasant winter barley varieties. In: Proc Inter Symp Cereal Adaptation to Low Temperature Stress (Bedõ Z, Sutka J, Tischner T, and Veisz O eds), Martonvásár Hungary. pp. 92-96.

Karsai I, Mészáros K, Hayes PM, and Bedõ Z. 1997. Effects of loci on chromosomes 2(2H) and 7(5H) on developmental patterns in barley (Hordeum vulgare L.) under different photoperiod regimes. Theor Appl Genet 94(5):612-618.

Kovács G and Barnabás B. 1997. Selection for frost tolerance in anther culture-derived embryos and regeneration of frost-tolerant fertile DH plants in winter wheat. Acta Agron Hung 45:285-293.

Láng L and Bedõ Z. 1997. Prebreeding of early maturing wheat germplasm for a continental climate. Acta Agronomica Hung 45(1):57-62.

Láng L, Bedõ Z, and Veisz O. 1997. Breeding frost-resistant wheat varieties using the phytotron facilities. Acta Agron Hung 45:337-342.

Mészáros K and Hayes PM. 1997. The Dicktoo x Morex barley mapping population. http://wheat.pw.usda.gov/ggpages/DxM/.

Mészáros K, Karsai I, Hayes PM, Veisz O, and Bedõ Z. 1997. Characterisation of barley genotypes with novel combinations of daylength sensitivity, vernalisation requirement and frost resistance. In: Proc Inter Symp Cereal Adaptation to Low Temperature Stress (Bedõ Z, Sutka J, Tischner T, and Veisz O eds), Martonvásár Hungary. pp. 250-254.

Páldi E, Szalai G, and Janda T. 1997. Effect of low temperature on nucleic acid synthesis in wheat and barley. Acta Agron Hung 45(3):215-221.

P·ldi E. - Szalai G. 1997. Effect of low temperature on the cytoplasmic ribosomal RNA synthesis in wheat and barley genotypes. In: Proc Inter Symp Cereal Adaptation to Low Temperature Stress (Bedõ Z, Sutka J, Tischner T, and Veisz O eds), Martonvásár Hungary. pp. 27-33.

Snape JW, Semikhodskii A, Fish L, Sarma RN, Quarrie SA, Galiba G, and Sutka J. 1997. Mapping frost tolerace loci in wheat and comparative mapping with other cereals. Acta Agron Hung 45:265-270.

Sutka J, Galiba G, and Snape JW. 1997. Inheritance of frost resistance in wheat (Triticum aestivum L.). Acta Agron Hung 45:257-263.

Szunics L, Szunics Lu, Veisz O, and Vida Gy. 1997. Sensitivity of cereal species to snow mould. Cereal Res Commun 25:819-820.

Szucs P, Veisz O, and Szunics L. 1997. Contribution of the Phytotron to the breeding of winter durum wheat (Triticum durum Desf.) for frost resistance. In: Proc Inter Symp Cereal Adaptation to Low Temperature Stress (Bedõ Z, Sutka J, Tischner T, and Veisz O eds), Martonvásár, Hungary. pp. 247-249.

Tímár I., Kristóf Z, and Barnabás B. 1997. Comparative studies on the male and femaly gametophyte development in three different Triticum species. Plant Sci 126:97-104.

Tuberosa R, Galiba G, Sanguineti MC, Noli E, and Sutka J. 1997. Identification of QTLs influencing freezing tolerance in barley. Acta Agron Hung 45:413-417.

Veisz O. 1997. Effect of abiotic and biotic environmental factors on the frost resistance of winter cereals. Acta Agron Hung 45:247-255.

Veisz O. 1997. Studies on the frost resistance of winter cereals in the Martonvásár Phytotron. In: Proc Inter Symp Cereal Adaptation to Low Temperature Stress (Bedõ Z, Sutka J, Tischner T, and Veisz O eds), Martonvásár, Hungary. pp. 109-115.

Veisz O, Bedõ Z, Láng L, and Tischner T. 1997. Genetic analysis of the frost resistance of wheat through diallel analysis. Acta Agronomica Hung 45:117-125.

Veisz O, Harnos N, Szunics L, and Tischner T. 1997. Owerwintering of winter cereals in Hungary in the case of global warming. In: Adaptation in Plant Breeding (Tigerstedt PMA ed). pp. 271-275.

Veisz O, Köszegi B, Sutka J, and Tischner T. 1997. Climatic programmes used for frost testing of cereals in the Martonvásár phytotron. In: Proc Inter Symp Cereal Adaptation to Low Temperature Stress (Bedõ Z, Sutka J, Tischner T, and Veisz O eds), Martonvásár Hungary. pp. 303-306.

Veisz O, Szunics Lu, and Szunics L. 1997. Effect of bunt infection on the frost resistance of wheat varieties and of lines containing Bt genes. Plant Breed 116:123-126.

 

CEREAL RESEARCH NON-PROFIT CO.

H-6701 Szeged, PF. 391, Hungary.

 

J. Matuz, Z. Kertész, L. Bóna, B. Beke, J. Pauk, M. Csosz, L. Cseuz, A. Mesterházy, I. Petroczy, L. Purnhauser, Cs. Kertész, M. Papp, T. Bartok, and J. Falusi.

 

This year, the name of the Cereal Research Institute was changed to the Cereal Research Non-Profit Co. However, our mission basically remains the same: development of new field crop varieties, seed production, and marketing for our home country and abroad.

 

Bread wheat growing conditions and cultivar release.

An average crop was harvested in 1997 in Hungary, with an estimated production of 1.25 million hectares of winter wheat and an average of 4,210 kg/ha. After a long winter and dry and hot late spring, an unusually long wet period occurred before and during harvest.

GK Kunsag: (GK Kincso / 2*GK Mini Mano) is a very early, awned, medium-height cultivar that has a particularly favorable grain and flour quality parameters, high farinographic value, and protein content. GK Kunsag is resistant to leaf rust.

GK David: (GK Mini Mano / GK Istvan) is an early, awnless, medium-height cultivar with B1­B2 farinographic category and high wet gluten content.

GK Garaboly: (D12 / GK Mini Mano) is an early, medium-height, awned cultivar with excellent lodging resistance. The wet gluten and protein contents of GK Garaboly are high, and the cultivar has field resistance to stem rust and powdery mildew.

GK Cipo: (Mv 15 / GK Istvan) is a medium maturity cultivar with a short, strong stem. GK Cipo is resistant to leaf rust races in the region and has a favorable flour yield (70-75 %) and stabile test weight (790-840 kg/m3).

GK Favorit: (GK Othalom / GK Mini Mano) is a medium maturity cultivar with a very short, strong stem. GK Favorit has a B1 farinographic value and excellent lodging resistance.

GK Mura: (J-50 / Produttore // Rn12 /3/ GKT5) is a medium maturity, semi-dwarf, awned cultivar with high yield and adaptability.

GK Mero: (GK Szoke / GK Zombor) is a medium-late maturity awnless, semi-dwarf cultivar. GK Mero shows field resistance to leaf diseases and Fusarium scab, and has excellent milling quality and B1 a farinographic value.

 

Evaluation of doubled haploids.

In a special program, starting from sublines of four cultivars, 726 doubled haploid lines have been produced by the anther culture method. The main aim of this work was to evaluate the agronomic value of the doubled haploid versions compared to the original

Seventeen typical sublines of four cultivars along with their 4-4 doubled haploid analogues were evaluated in yield trials in two locations, Szeged and Godollo, in Hungary. Plot size was 5 m2, and 4 and 2 replications were made, respectively. Seeding rate was 550 seeds/m. No significant differences were found for grain yield between the original strains and their DHs or within cultivars. The same results were observed for agronomic characteristics of height, heading time, and 1,000-kernel weight. Thus, DH lines produced by anther culture are comparable agronomically to those produced conventionally.

 

Genotype preservation.

Genebank activity is ongoing at the Wheat Department of the Company by the support of the Hungarian Ministry of Agriculture. The aim of this genebank program is the medium-term preservation of the local cultivars or advanced lines selected by the company. Last year 350 genotypes were included to the active collection where they were evaluated according to the International Board of Plant Genetic Resources (IBPGR) system of characterisation using descriptors to focus on morphological and highly heritable characteristics. All samples also were evaluated with an SDS-sedimentation test to get a rough estimate of breadmaking quality. Resistance to rusts and powdery mildew was scored by a modified Cobb's scale at the adult stage and by Stakman's scale for seedlings. All entries were planted in 12 m-long one-row plots for seed increase and continued studies. Seed samples are stored in a cold chamber in glass containers at 5 C at the Company's breeding station in Kecskes-telep, Szeged.

 

Leaf diseases.

In 1997, 1,200 genotypes were tested against powdery mildew and leaf rust, and 900 genotypes were screened for stem rust infection. The rates of powdery mildew (ACI index: 9.5) and leaf rust (ACI index: 23.4) epidemics among the lines tested were significantly less than in previous years. Artificial infection also was used to study stem rust resistance in winter wheat cultivars. Stem rust has not caused a severe epidemic in the last 10-15 years. The average epidemic rate (ACI index 35.1) was 10 % higher than that in 1996. Resistance to leaf rust was due to Lr19, Lr4, Lr25, Lr29, Lr25, and Lr38. Fo powdery mildew, resistance gene Pm6 or its combinations gave appropriate field resistance. Stem rust resistance gene Sr36 continued to provide protection. This gene was introduced in the cultivar Arthur 71 to improve the stem rust resistance in the Hungarian wheat cultivar GK Kincso and its derivatives GK Gobe, GK Zugonly, GK Kunsag, GK Szindbad, GK Kalasz, GK Veka, and GK Garaboly, all of which have a high resistance to stem rust.

 

Resistance to insects and viruses.

Resistance tests based on estimation of leaf-feeding damage by cereal leaf beetle and infestation by bird cherry-oat aphid were carried out on 31 winter wheat cultivars with artificial infestation in field cages covered by insect nets in 1993­96. Highly significant differences were found between cultivars in leaf-feeding damage by O. malanopus, infestation severity by R. padi, loss of yield, and 1,000-kernel weight. The most resistant genotype had 45 % leaf feeding damage by O. malanopus, and the most susceptible had 89 %. The average yield reduction caused by O. melanopus was 40 %, with extremes of 24 and 51 %. Infestation values by R. padi varied between 19 and 39 %. The average yield decrease caused by R. padi wa