GrainGenes

ITEMS FROM HUNGARY

 

AGRICULTURAL RESEARCH INSTITUTE OF THE HUNGARIAN ACADEMY OF SCIENCES

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

 

The wheat season. A severe drought in autumn 2000 was followed by a much warmer winter than usual. Because of the drought in spring and early summer and an epidemic of yellow rust, which was the first ever experienced in Hungary, flag leaves withered very early in many locations. Despite the unfavorable weather, a fairly good yield was harvested, though the protein content of the grain was lower than in previous years. Persistent rain experienced during harvest led to a further deterioration in the quality. Good bread-making quality was achieved most frequently with varieties such as Mv Magdaléna, Mv Cseardás, and Mv Magvas, which have genetically high protein content, resistance to yellow rust, and a stable falling number. [p. 65]

Breeding. [p. 66-70]

Z. Bedö, L. Szunics, L. Láng, O. Veisz, I. Karsai, A. Juhász, M. Rakszegi, Gy. Vida, P. Szücs, Cs. Kuti, M. Megyeri, and M. Gál.

Breeding. Five Martonvásár-bred winter wheat varieties were registered in 2001.

Mv Verbunkos (Mv 218-98) is a new, top-quality wheat with good agronomic properties. Selected from the cross 'GT2412/Mv15//Fatima', the new variety has 14.5-15 % protein and a 37-41 % wet-gluten content, A2 farinograph value, very good sprouting resistance, and high water uptake under Hungarian conditions. Mv Verbunkos outyielded Mv Emma, an older variety with similar quality, by 10-12 %. The outstanding quality is accompanied by good stability. The variety has reliable frost resistance and good field resistance to powdery mildew, stem rust, and yellow rust.

Mv Mambo (Mv 28-98) is an extra early maturing, hard red, awned wheat (pedigree: GK Kalaka/Mv16//F2076) characterized by very good baking quality. Mv Mambo has excellent frost and lodging resistance; good resistance to powdery mildew, leaf rust and stem rust; and very good resistance to yellow rust.

Mv Marsall (Mv 29-987) is an early, hard red wheat variety. Selected from the cross 'MvC410-90/GK Kalaka// MvC410-90/Fatima', the variety has high yield, good bread-making quality, and very good sprouting resistance and water uptake. Mv Marsall is frost resistant, has good lodging resistance, moderately resistant to powdery mildew and stem rust, and has a high level of resistance to leaf rust.

Mv Amanda (Mv 213-98) is a very attractive, high-yielding awnless variety (pedigree: Mv Palma/GK Kalaka//Mv Palma/Fatima). Baking quality is A2-B1, with a 31-32 % wet-gluten content. Mv Amanda is moderately resistant to leaf rust and powdery mildew, and has medium frost resistance.

Mv Panna (Mv 25-98) is an early, hard red bread wheat (pedigree: Mv213-88/F2076) with a wet-gluten content of 31-32 % and farinograph quality of A2. The variety has good field resistance to powdery mildew and yellow rust.

Computerized management system for cereal breeding. A program for wheat breeding was compiled in Martonvásár in 1983 and was used for over 10 years with minor modifications to satisfy breeding requirements. Due to new ideas and advances made in the field of computer and other technologies, the data structure and program system have been redesigned. The chief emphasis in developing the Martonvásár Wheat Breeding Software was because of the handling of genealogical and observation data and on the classifications required for well-based selection decisions. The widely-used Windows 9x/NT/2000 operational system, MSAccess data base-handling system, and Visual Basic 5.0 programming language were chosen for this purpose. The subprograms controlling major breeding tasks include the transfer of the data of the selected lines with the necessary modifications to the data base of the new experimental year, the handling of new crosses and seed shipment data, the preparation of the field plan, various output (labels, fieldbooks), and input (manual, online) possibilities and a simple statistical module.

Transgenic wheat studies. Transgenic wheat seedlings have been produced containing the gene used for selection and the gene of the Dx5 HMW-glutenin protein subunit chosen for transfer. In the course of this work, 47 transformed, regenerated wheat plants were obtained, in 12 of which the presence of the incorporated gene could be clearly demonstrated.

In a joint British­Australian experiment, the transgenic wheat line B73-6-1, developed from the Australian spring wheat L88-6, which contains extra copies of the 1Dx5 HMW-glutenin gene, was retested in field experiments. A field comparison of the transformant and the original genotype indicated that the protein content, wet-gluten content, grain hardness, and Zeleny, SDS and RMT indexes were greater than those of the control under central European conditions; whereas the extensibility and elasticity of the dough were poorer. The over-expression of the 1Dx5 HMW-glutenin subunit thus appears to result in extra-strong dough, making it suitable for blending with poorer quality flours or for novel end-uses.

Storage protein studies in old Hungarian wheat germ plasm. On the basis of its HMW and LMW glutenin and gliadin allele composition, the quantitative traits of its storage proteins, and the quality traits of the lines, the population of the old Hungarian wheat variety Bánkúti 1201 can be divided into two subgroups based on the 7+8 or 7+9 alleles coded at the Glu-B1 locus. The differences found in these two types mask the effects of the other loci (e.g., the 2*B allele first identified in Bánkúti 1201, which contains an extra cysteine and is coded at Glu-A1), or allows them to be expressed only through their interactions. Lines possessing alleles Glu-B3i and Gli-A1m, which are characteristic of the population, have strong extensibility. In approximately 60 % of the lines tested, the Glu-B1 7+9 allele was detected in association with Glu-B3i and Gli-A1m. The joint presence of these alleles and the interactions between them ensure the high protein and gluten contents and the good extensibility characteristic of one type in the population. The other group of lines, which have alleles 7+8 at the Glu-B1 locus, have a greater Glu-B1x subunit content, greater insoluble polymeric glutenin content, and, thus, a more stable, stronger dough structure, and smaller extensibility than the previous group. The complex high quality of the variety, i.e., the balance between strong and stable, but nevertheless extensible gluten, is thought to be attributed to a satisfactory proportion of these two types (~ 60 % 7+9 and ~ 40 % 7+8).

Vernalization studies. The optimum and minimum vernalization requirements of the 50 winter wheat varieties grown over the last 50 years or currently grown on large areas in Hungary were tested under controlled conditions in the phytotron and in the field and expressed as the time required to heading. The close, significant (r = 0.961***) correlation observed between the heading dates in the phytotron and field proved that, with the exception of Mironovskaya 808, a 55-day vernalization treatment was sufficient to completely satisfy the cold requirements of the tested varieties. The vernalization requirements demonstrated in the experiment, which ranged from 35 to 55 days, were in line with those characteristic of the winter wheat species. The minimum vernalization requirements ranged from 0-30 days, depending on the variety. The wheat varieties Skorospelka 3b, Mv 10, Korona, Fatima 2, and Alföld 90 represented a special type, since they were capable of heading, though protractedly, even without vernalization. Without exception, the pedigrees of the varieties with the shortest optimum vernalization requirements included parents of southern origin or of spring type. We found that under experimental plant growth conditions (in the greenhouse or phytotron) the majority of the varieties headed at the date characteristic of the genotype, after 35-45 days of vernalization.

Winter durum frost-resistance studies. Data from the phytotron and overwintering data recorded in field showed that on average T. durum genotypes achieve a lower level of hardening that lasted for a shorter period than that of the winter T. aestivum varieties. The frost resistance of durum varieties and the moisture content of the soil indicated a negative correlation. Using RAPD primers, polymorphisms were demonstrated between the durum genotypes despite the relatively restricted genetic basis. Tests with RFLP probes located on barley chromosome 5H failed to demonstrate any substantial differences between the genotypes. We used a bulked-segregant analysis and RAPD primers on the F2 generation of a spring/winter durum cross. The sensitive genotypes gave an extra amplification product with OPS04 primer. On the basis of regression analysis, the presence of this product reduced the frost resistance by an average of 37 %. The segregation of the OPS04 marker explained 40 % of the phenotypic distribution in the population.

Sprouting resistance studies. Tests were made on the falling number stability of the grain of triticale and wheat plants grown in the phytotron. By applying artificial precipitation and increased humidity treatments during the second half of grain filling and in the over-ripe stage, genotypic differences could be detected in the decline in the falling number, but the date and duration of treatment also had a significant influence on changes in quality.

Winter durum wheat breeding. In winter durum wheat breeding the most important aim continues to be an improvement in the frost resistance and winter hardiness and in the pasta-making quality and productivity. The winter durum wheat varieties Mv Maxi and Mv Makaróni were state registered in 2001. Mv Maxi is a high-yielding variety with good technological quality and excellent adaptability. Mv Makaróni had excellent cold tolerance in phytotron tests and has one of the highest yellow pigment contents of all the winter durum wheat varieties bred in Hungary. Last autumn, two high-yielding, cold-tolerant lines with satisfactory technological quality were entered for state trials. The molecular genetics laboratory continues to work on the elaboration of a marker-assisted selection method to improve the efficiency of selection for higher yellow pigment content.

Polymorphism was detected using RAPD primers between the durum genotypes, which have a relatively restricted genetic basis. The durum genotypes examined did not exhibit any significant difference with RFLP probes localized on the 5H chromosome of barley. A bulk-segregant analysis was made in the F2 generation of a spring/winter durum cross using RAPD primers. Frost-sensitive plants gave an extra amplification product with the OPS04 primer. Regression analysis revealed that the presence of this product reduced the frost resistance of the plants by an average of 37 %. The segregation of the OPS04 marker explained 40 % of the phenotypic segregation in the test population.

Disease resistance studies. The degree of infection in genotypes carrying known leaf and stem rust resistance genes was investigated in artificially inoculated nurseries. We found that in 2001 the resistance genes Lr9, Lr19, Lr24, Lr25, Lr29, and Lr35 gave complete protection against leaf rust. Near-isogenic lines for genes Lr23 and Lr37 had 10 % or less infection. As observed last year, certain resistance genes which were previously effective against leaf rust exhibited a greater degree of infection in 2001 (Lr13, Lr18, Lr21, Lr34, Lr38, Lr44, LrB, and LrW). Varieties with the genes Sr5+6+8a+17, Sr7a, Sr9b, Sr9d+12+24, Sr11, Sr27, Sr31, Sr36, Sr37, SrDr+1, SrTt3, and SrGT had little infection with stem rust.

As in many other parts of the country, a local yellow rust epidemic of natural origin developed in Martonvásár in 2001. Although no effort to breed for yellow rust resistance is made at the institute, a large proportion of the varieties exhibited a greater or lesser extent of resistance to the pathogen. Among the varieties state registered in recent years, Mv Madrigál, Mv Palotás, Mv Mezföld, Mv Optima, Mv Emma, Mv Magvas, Mambo, Mv Panna, and Mv Csárdás had excellent resistance.

The race composition and virulence of the natural powdery mildew population found in the Martonvásár area and the efficiency of known resistance genes were examined in the greenhouse under controlled conditions. In 2001, the dominant races of wheat powdery mildew (and their frequency) were as follows: 63 (22.37 %), 90 (14.47 %), 72 (13.2 %), 77 (12.5 %), and 70 (7.24 %). The number of virulence genes in the pathogen population was 4.35. The resistance genes Pm4a (Khapli), Pm1+2+9, Pm2+Mld, Pm4b+ and Pm4a+ provided satisfactory protection against the wheat powdery mildew pathotypes identified.

The resistance of 216 T. aestivum and 34 T. durum varieties and breeding lines and 63 foreign resistance sources to spike Fusarium was tested in an irrigated experiment with artificial inoculation. The intensity of infection (spike infection, grain mass changes, visible grain infection and grain infection apparent during germination) was evaluated in the field and in the laboratory. The variety Mv Palotás was again outstandingly resistant in 2001 on the basis of infection determined after incubation. An additional seven breeding lines were found with an average Fusarium infection of less than 10 %. Among the sources of resistance, Frontana, Nobeokabozukomugi, BVAL213064, and Praag8 showed the least infection.

The team also is involved in the development of resistant varieties (T. aestivum) to serve as the biological basis for environment-friendly, cost-saving plant protection and production technologies. The majority of the newly registered wheat varieties (Mv Panna, Mv Marsall, Mv Amanda, Mv Verbunkos, and Mambo) have good powdery mildew resistance, whereas some (Mv Marsall and Mv Amanda) are resistant to leaf rust and several (Mv Verbunkos, Mv Panna, and Mv Marsall) have good stem resistance. Complex resistance, or slight susceptibility to several pathogens, also provides the varieties with satisfactory protection.

Abiotic stress resistance studies. Various components of the antioxidant defence system were studied to determine the effect of various nitrogen sources (NH^4+^, NO^3­^, and NH4NO3) and salt treatment (NaCl) on Martonvásár wheat varieties grown in liquid culture. As a response to various stress factors, there is a rise in the concentration of free radicals and active oxygen species in living organisms. The antioxidant defence system provides protection against the ensuing damage. Changes in the environmental conditions (such as different nitrogen sources or salt treatment) may also act as stress factors. Changes were recorded in the activities of the glutathione reductase, superoxide dismutase, guaiacol peroxidase, catalase, and glutathione-S-transferase enzymes, and it was observed that in some of the enzymes ammonium treatment induced an increase in activity similar to that caused by salt treatment.

The investigations also covered the effect of salt treatment and different nitrogen sources on the isoforms of the antioxidant enzymes. We concluded from the results that ammonium ions act as a stress signal, which induces the activation of certain enzymes responsible for early stress adaptation processes. Some of these enzymes, such as guaiacol peroxidase, and catalase, respond with a change in activity, whereas in others (glutathione reductase and superoxide dismutase) a new isoform appears.

In connection with cold-tolerance studies, changes in the activity of antioxidant enzymes were examined on a total of 13 varieties. Leaf samples were taken for analysis in December, January, and February. The enzyme activity was highest in December for glutathione reductase and in January for ascorbate peroxidase, guaiacol peroxidase, catalase, and glutathione-S-transferase. The varieties could be divided into two groups; one with poor cold tolerance and one with good frost resistance. The differences in enzyme activities indicate that the different groups follow different strategies to counteract the oxidative stress caused by the cold.

In phytotron tests to investigate the effects of possible global climate changes, a substantial increase in biomass was observed in the early stages of development as the result of increased atmospheric CO2 concentration. This increase in atmospheric CO2 concentration had a greater effect on the vegetative biomass than on the grain yield.

The effect of increased atmospheric CO2 concentration differed not only for different cereal species, but also within the species for varieties with different genetic backgrounds. The yield-increasing effect of higher atmospheric CO2 concentration was able to compensate in part for the yield-reducing effect of rainfall deficiency, so the grain yield losses were lower than in drought-stressed plants grown at normal atmospheric CO2 concentration.

 

Publications.

• Bedö Z and Láng L. 2001. Wheat in the host country. In: Wheat in a Global Environment, Proc 6th Internat Wheat Conf (Bedö Z and Láng eds). Developments in Plant Breeding, Kluwer Academic Publishers, the Netherlands. pp. 781-786.
• Bedö Z and Láng L eds. 2001. Wheat in global environment: Proc 6th Internat Wheat Conf. 5-9 June, 2000, Budapest, Hungary. Developments in Plant Breeding, Kluwer Academic Publishers, the Netherlands. 325 pp.
• Bedö Z, Láng L, Sutka J, and Molnár-Láng M. 2001. Hungarian wheat pool. In: The World Wheat Book. A History of Wheat Breeding (Bonjean AP and Angus WJ eds). Lavoisier Publishing, Paris, France. pp. 193-218.
• Bedö Z, Malesevic M, and Láng L. 2001. Exploitation of genetic yield potential in small grain crops. In: Genetics and Breeding of Small Grains (Quarrie SA, Janjic V, Atanassov A, Knezevic D, and Stojanovic S eds). Grafika Jures-Cacak. pp. 453-512.
• Bedö Z, Szunics L, Láng L, Szunics Lu, Veisz O, Karsai I, Vida Gy, Szücs P, Juhász A, and Rakszegi M. 2001. Items from Hungary, Department of Wheat Breeding, Agricultural Research Institute, Martonvásár. Ann Wheat Newslet 47:56-59.
• Costa JM, Corey A, Hayes PM, Jobet C, Kleinhofs S, Kopisch-Obusch A, Kramer SF, Kudrna D, Li M, Riera-Lizarazu O, Sato K, Szücs P, Toojinda T, Vales MI, and Wolfe RI. 2001. Molecular mapping of the Oregon Wolfe Barleys: a phenotypically polymorphic doubled-haploid population. Theor Appl Genet 103:415-424.
• Juhász A, Larroque OR, Tamás L, Vida Gy, Zeller FJ, Békés F, and Bedö Z. 2001. Biochemical and molecular genetic background of the traditional Bánkúti breadmaking quality. In: Proc CHL 2000 11th Cereal and Bread Cong. 8-15 September, 2000, Gold Coast, Aus. pp. 699-702.
• Juhász A, Tamás L, Karsai I, Vida G, Láng L, and Bedö Z. 2001. Identification, cloning and characterisation of a HMW-glutenin gene from an old Hungarian wheat variety, Bánkúti 1201. Euphytica 119(1­2):75-79.
• Juhász A, Tamás L, Karsai I, Vida Gy, Láng L, and Bedö Z. 2001. Identification, cloning and characterisation of a HMW-glutenin gene from an old Hungarian wheat variety, Bánkúti 1201. In: Wheat in a Global Environment, Proc 6th Internat Wheat Conf (Bedö Z and Láng eds). Developments in Plant Breeding, Kluwer Academic Publishers, the Netherlands. pp. 183-188.
• Karsai I, Mészéros K, Láng L, Hayes PM, and Bedö Z. 2001. Multivariate analysis of traits determining adaptation in cultivated barley. Plant Breed 120(3):217-222.
• Láng L, Kuti Cs, and Bedö Z. 2001. Computerised data management system for cereal breeding. In: Wheat in a Global Environment, Proc 6th Internat Wheat Conf (Bedö Z and Láng eds). Developments in Plant Breeding, Kluwer Academic Publishers, the Netherlands. pp. 561-569.
• Láng L, Kuti Cs, and Bedö Z. 2001. Computerised data management system for cereal breeding. Euphytica 119(1-2): 235-240.
• Rakszegi M, Békés F, Juhász A, Szücs P, Láng L, Tamás L, Shewry PR, and Bedö Z. 2001. Technological quality of a transgenic Australian spring wheat variety under Central European conditions. In: Proc CHL 2000 11th Cereal and Bread Cong, 50th Aus Cereal Chem Conf, 8-15 September 2000, Gold Coast, Aus. pp. 261-264.
• Rakszegi M, Tamás C, Szücs P, Tamás L, and Bedö Z. 2001. Current status of wheat transformation. J Plant Biotech 3(2):67-81.
• Szunics L, Szunics Lu, Vida G, Bedö Z, and Svec M. 2001. Dynamics of changes in the races and virulence of wheat powdery mildew in Hungary between 1971 and 1999. Euphytica 119(1-2):143-147.
• Szunics L, Szunics Lu, Vida Gy, Bedö Z, and Svec M. 2001. Dynamics of changes in the races and virulence of wheat powdery mildew in Hungary between 1971 and 1999. In: Wheat in a Global Environment, Proc 6th Internat Wheat Conf (Bedö Z and Láng eds). Developments in Plant Breeding, Kluwer Academic Publishers, the Netherlands. pp. 373-380.
• Tolmay VL, Basky Zs, and Láng L. 2001. Assessing Russian wheat aphid resistance in Hungarian and South African germplasm. In: Wheat in a Global Environment, Proc 6th Internat Wheat Conf (Bedö Z and Láng eds). Developments in Plant Breeding, Kluwer Academic Publishers, the Netherlands. pp. 411-414.
• Veisz O, Braun HJ, and Bedö Z. 2001. Plant damage after freezing, and the frost resistance of varieties from the facultative and winter wheat observation nurseries. Euphytica 119(1-2):179-183.
• Veisz O, Braun HJ, and Bedö Z. 2001. Plant damage after freezing, and the frost resistance of varieties from the facultative and winter wheat observation nurseries. In: Wheat in a Global Environment, Proc 6th Internat Wheat Conf (Bedö Z and Láng eds). Developments in Plant Breeding, Kluwer Academic Publishers, the Netherlands. pp. 481-486.
• Veisz O, Láng L, and Bedö Z. 2001. Studies on the winter hardiness and frost resistance of winter oat varieties. In: Proc 6th Internat Oat Conf (Cross RJ ed). 13-18 Novermber, 2000. pp. 322-326.
  

Department of Genetics. [p. 70-71]

J. Sutka, G. Galiba, M. Molnár-Láng, G. Kocsy, G. Kovács, G. Linc, A. Vágújfalvi, E.D. Nagy, A.F. Bálint, B. Tóth, and I. Molnár.

Cold-hardening studies. Using some of the chromosome substitution lines developed from the crosses of the donor Cheyenne to Chinese Spring, it was shown that the accumulation of water-soluble carbohydrates during different stages of hardening was time dependent. Moreover, there was a significant correlation between the rate of carbohydrate accumulation and the frost tolerance. The expression and regulation of a wheat gene homologous to the cold-regulated barley cor14b gene was compared in frost-sensitive and frost-tolerant wheat genotypes at different temperatures. Studies made with chromosome substitution lines showed that the threshold induction temperature polymorphism of the cor14b wheat homologous gene was controlled by loci located on chromosome 5A of wheat, whereas in T. monococcum, the cor14b gene was mapped on the long arm of chromosome 2A^m^. A study on the effect of cold hardening on the glutathione (GSH) metabolism showed that chromosome 5A of wheat has an influence on the GSH accumulation and on the ratio of reduced and oxidized glutathione as part of a complex regulatory function during cold hardening. In addition, the level of increase in the GSH content during hardening may indicate the degree of frost tolerance in wheat.

Drought-tolerance analysis. To evaluate the genetic background of quantitative criteria of drought tolerance in wheat, six generations of a cross between the varieties Plainsman and Cappelle-Desprez were grown in a randomized complete block design with three replications in the greenhouse of the College of Agriculture, University of Tehran, in 1997. Genetic variation was found for yield potential (Yp), stressed yield (Ys), excised-leaf water retention (ELWR), relative water loss (RWL), relative water content (RWC), and harvest index (HI) under water stress conditions. High heterosis and heterosis were observed in the F1 hybrid for Ys, HI, and spike-yield index (SYI). Genetic analysis exhibited overdominance in the inheritance of Ys, RWL, ELWR, HI, biomass, and SYI, whereas RWC and Yp were controlled by the additive type of gene action. High narrow-sense heritability estimates were found for ELWR, biomass, and SYI. The high genetic advance for ELWR, RWC, HI, and SYI indicated that direct selection could be effective for these traits. The epistatic effects (additive x additive = [i] for Yp, Ys, and RWL, additive x dominance = [j] for ELWR, and dominance x dominance = [l] for RWL) were found to be exceedingly large.

Nutrient composition studies. Cereals, especially common wheat, are the most important staple food; however, their grains often contain very low amounts of available iron (Fe), zinc (Zn), copper (Cu), and manganese (Mn). The aim of the present research was to study the existing variability in the seed inorganic nutrient composition of various Triticum and Aegilops species and investigate the hypothesized correlation between the ploidy level and the seed mineral nutrient concentrations. The results showed that higher copper (Cu), zinc (Zn), calcium (Ca), and magnesium (Mg) contents were generally observed in the caryopsis of Aegilops species, whereas higher iron (Fe) concentration was found in the grains of Triticum accessions. The results do not confirm the hypothesis that the grains of the ancient wheat species (einkorn, emmer, and spelt) generally have higher mineral nutrient contents than the recently cultivated varieties, except for Fe, which is contained in a higher amount in the seeds of diploid wheat species. No correlation was found between the ploidy level and genome types (A, AB, AG, ABD, S, D, UM, and DMS) and the mineral nutrient content of the grains. Similar results were found using hierarchical cluster analysis. Because the 1,000-kernel weight of wild species is generally smaller than that of cultivated species, the correlation between seed weight and mineral-nutrient concentrations also was studied. The results showed that the increase in seed weights correlated significantly with the decrease in Ca and Mg concentrations. The results showed that to improve the human nutritional quality of wheat varieties, the best sources of higher Cu, Zn, Ca, and Mg content could be found in the Aegilops genus, whereas genotypes with higher Fe content could be found in the genus Triticum.

Cereal Gene Bank activity. The Cereal Gene Bank in Martonvásár was founded in 1992 and contains not only 3,150 common wheat and maize varieties and genotypes but also samples belonging to other cereal species, including numerous accessions of wild wheat relatives and other valuable genetic stocks. Besides classical gene bank activities, several research programs have been initiated for the evaluation and exploitation of the genetic diversity of various wheats, wheat-related species, and their hybrids. These programs cover the use of classical genetic methods, in situ hybridization, and other molecular-genetic techniques. Recently, special attention has been given to the diploid Triticum species, especially to einkorn. Based on a relatively large collection (about 160 einkorn accessions), a new prebreeding method was developed to produce agronomically useful lines of einkorn.

Identification of wheat-barley translocations. Five wheat-barley translocations in a wheat background were characterized through a combination of cytogenetic and molecular genetic approaches. The wheat chromosome segments involved in the translocations were identified using sequential GISH and two-color FISH with the probes pSc119.2 and pAs1. The barley chromatin in these lines was identified using SSR markers. A total of 45 markers distributed over the total barley genome were selected from a recently published linkage map of barley and screened on the translocation lines. The following translocations were identified: T2DS·2DL-1HS, T3HS·3BL, T6BS·6BL-4HL, T4D-5HS, and T7DL·7DS-5HS. Wheat-barley disomic and ditelosomic addition lines for the chromosomes 3HS, 4H, 4HL, 5H, 5HL, and 6HS were used to determine the correct localization of 21 markers and the position of the centromere. An ancient intragenomic rearrangement between chromosome arms 1HL and 5HS was detected in barley. Physical mapping of the SSR markers on chromosomes 1H and 5H was made using the intragenomic and interspecific translocation breakpoints and the centromere as physical landmarks.

Diploid pollen production in in vitro floret cultures of cereals using colchicine treatment. Colchicine, the well-known antimitotic alkaloid, has long been used for the reduplication of the genomes of animal and plant cells. In the present experiments spikelet cultures of one T. monococcum and one T. turgidum subsp. carthlicum genotype, four rye (Amilo, Lovászpatonai, Merkator, and Motto), and two barley (Igri and Mv 50) varieties were exposed to colchicine treatment in various stages of development.

In each variety, seed set only occurred when the anthers of the cultured spikelets contained microspores in the binuclear stage. On nutrient medium with a pH of 5.8, seed set was only recorded in the barley variety Mv 50 cultured on control medium. When the pH of the medium was adjusted to 4.5, the barley variety Igri performed well. This variety also set seeds on control medium containing 0.02 % or 0.04 % colchicine. In the case of rye, seed set only was observed in the variety Merkátor. Seedlings were successfully grown on germinating medium by excising the embryos from the endosperm-deficient seeds.

From the microscopic analyses, we could see that a colchicine treatment led to a drastic reduction in the number of viable microspores, but the vast majority of those that survived developed into trinuclear pollen. In some of the pollen grains the cell nuclei were considerably bigger than in those developed on control medium, suggesting that they were diploid cell nuclei. In T. turgidum subsp. carthlicum, MK cytological analysis of the offspring revealed a triploid karyotype (3n = 42), indicating the fusion of gametes with different chromosome numbers.

Based on the preliminary results, the colchicine treatment of floret cultures would appear to be an efficient alternative method in polyploid research.

 

Cell biology studies. [p. 71-72]

An isolated microspore-culture system was optimized in wheat for cocultivation with in vivo fertilized zygotes. However, the media requirements of microspores and isolated zygotes are different. An MMS3 medium (Hu et al. 1997. Plant Cell Rep. 16: 520-525) with 90 g/l maltose was suitable for growing zygotes isolated 18-22 hours after pollination into plants (14 fully fertile plants from 76 isolated zygotes). For microspore cultures and zygotes, the cultivars Mv Pálma and Siete Cerros, respectively, were used. Applying these genotypes the matured plants originated from the microspores and zygotes are easily discernible. This is the first report about growing zygotes with microspores, as nurse cells, from the same species.

Characterization of aluminium tolerance of wheat genotypes selected by microspores. Fertile dihaploid plants were regenerated from microspores selected under conditions of aluminium stress. The selection did not cause alteration in the fertility. However, under stress conditions (i.e., in hydroculture system containing aluminium at low pH), these genotypes accumulate lower amount of aluminium and represent a higher root growth than the Al-sensitive plants. Aluminium accumulation could not be observed in leaves.

In vitro fertilization of isolated egg cells of wheat was made and the dynamics of actin filaments during in situ egg-cell development, and postfertilization was analyzed by using fluorescence-labeled, microinjected F-actin-specific phalloidin. Based on these results, a scenario addressing the potential role of the actin filaments in governing zygotic cell cleavage was drawn. By capitalizing on the ratio approach and microinjecting ER-specific fluorochromes and ER Ca-ATPase-specific inhibitors, the signal transduction of egg cell activation was followed up in in vitro fertilized female gametes isolated from wheat.

 

Publications.

• Bálint AF, Kovács G, Erdei L, and Sutka J. 2001. Comparison of the Cu, Zn, Fe, Ca and Mg contents of the grains of wild, ancient and cultivated wheat species. Cereal Res Commun 29:375-382.
• Balla A, Tóth B, Tímár G, Bak J, and Krajcsi P. 2001. Molecular targets for pharmacological cytoprotection. Biochem Pharm 61:769-777.
• Bedö Z, Láng L, Sutka J, and Molnár-Láng M. 2001. Hungarian Wheat Pool. In: The World Wheat Book. A History of Wheat Breeding (Bonjean AP and Angus WJ eds). Lavoisier Publishing, Paris. pp. 193-218.
• Farshadfar E, Ghanadha M, Zahravi M, and Sutka J. 2001. Generation mean analysis of drought tolerance in wheat (Triticum aestivum L.) Acta Agron Hung 49:59-66.
• Galiba G, Kerepesi I, Vágújfalvi A, Kocsy G, Cattivelli L, Snape JW, and Sutka J. 2001. Mapping of genes involved in glutathione, carbohydrate and COR14b cold-induced protein accumulation during cold hardening in wheat. Euphytica 119:173-177.
• Galiba G, Kerepesi I, Vágújfalvi A, Kocsy G, Cattivelli L, Snape JW, and Sutka J. 2001. Mapping of genes involved in glutathione, carbohydrate and COR14b cold-induced protein accumulation during cold hardening in wheat. In: Wheat in a Global Environment, Proc 6th Internat Wheat Conf (Bedö Z and Láng eds). Developments in Plant Breeding, Kluwer Academic Publishers, Dordrecht, the Netherlands. pp. 457-462.
• Kocsy G, Tóth B, Berzy T, Szalai G, Jednákovits A, and Galiba G. 2001. Glutathione reductase activity and chilling tolerance are induced by a hydroxylamine derivative BRX 156 in maize and soybean. Plant Sci 160:943-950.
• Molnár-Láng M, Linc G, and D. Nagy E. 2001. Production and molecular cytogenetic analysis of wheat-barley hybrids and translocations. In: Wheat in a Global Environment, Proc 6th Internat Wheat Conf (Bedö Z and Láng eds). Developments in Plant Breeding, Kluwer Academic Publishers, Dordrecht, the Netherlands. 721-726.
• Snape JW, Sarma R, Quarrie SA, Fish L, Galiba G, and Sutka J. 2001. Mapping genes for flowering time and frost tolerance in cereals using precise genetic stocks. Euphytica 120:309-315.
• Sutka J. 2001. Genes for frost resistance in wheat. Euphytica 119:167-172.
• Sutka J. 2001. Genes for frost resistance in wheat. In: Wheat in a Global Environment, Proc 6th Internat Wheat Conf (Bedö Z and Láng eds). Developments in Plant Breeding, Kluwer Academic Publishers, Dordrecht, the Netherlands. 471-479.