GrainGenes

ITEMS FROM ESTONIA

INSTITUTE OF EXPERIMENTAL BIOLOGY AT THE ESTONIAN AGRICULTURAL UNIVERSITY

76902, Harku, Estonia.

 

Possible strategy for improvement of wheat grain quality in Estonia.

M. Tohver, R. Koppel*, and A. Ingver*.
* Jõgeva Plant Breeding Institute, Jõgeva MK, 48309.

Wheat breeding in Estonia was established by Earl Berg in the mid 19th century. Wheat cultivation became more popular in the 1920s and 1930s as the result of experiments and publications by the Jõgeva Plant Breeding Institute. Under Soviet rulers, the baking quality of wheat in Estonia was strongly influenced mostly by the wheat cultivars Leningradka and Mironovskaya 808 from Russia and Arkas from Germany. Recent breeding efforts have involved cultivars and breeding lines mainly from Scandinavian countries, where the climatic conditions are similar to those in Estonia. Today, foreign cultivars that are early and high in protein content, and have optimal gluten content and quality, good resistance to sprouting, and high-yield ability are selected as crossing parents (Koppel and Ingver 1999).

One of the objectives of wheat breeding in Estonia is high-quality grain for baking. In 1994, coöperation began with Finnish Boreal Plant Breeding. A number of spring wheat breeding lines from different generations arrived. In 1997 and 1998, the composition and HMW-glutenin subunits of 27 advanced breeding lines obtained from Boreal and 12 foreign cultivars, all grown in Estonia, were determined using A-PAGE and SDS-PAGE. This investigation was made in coöperation with the Jõgeva Plant Breeding Institute and Institute of Experimental Biology.

Payne and coworkers (1981) demonstrated a clear relationship between the glutenin subunit composition of wheat grain and baking quality that could be used as a selection criterion in breeding programs. These results were confirmed and extended to other quality tests using other genotypes in different countries.

In our work, a limited number of combinations of HMW glutenin was established in the advanced breeding lines. The most common represented alleles were Glu-A1b (2*), Glu-B1b (7+8), Glu-D1a (2+12), and GluD1d (5+10). Two advanced breeding lines contained HMW-glutenin bands 14+15 encoded by the Glu-B1. The lines also were evaluated for agronomic and baking quality. Nine of the 27 lines were suitable as donor cultivars in improving baking quality, and four were preserved in the genebank as carriers of some unique qualities (e.g., rare glutenin composition, good sprouting resistance). Tests confirmed the suitability of the three lines to be put on the Variety List. "The comparison of spring wheat breeds" by R. Koppel was based on this work and a Master of Science thesis was defended in June 1999. This study represents the first attempt to investigate the allelic variation of storage proteins in the wheat material used in breeding in Estonia.

The subunits of glutenin were resolved by SDS-PAGE, the established method of identifying and cataloguing the various subunits (Payne and Lawrence 1983). Catalogs of wheat glutenin subunits have been created for many cultivars in several countries. To develop new cultivars with improved bread making quality, it would be useful to cross genotypes having complementary subunits of good quality coded by different loci and then to select progeny with high Glu-1 scores. The combination of HMW subunits as 1 (Glu-A1a), 7+9 (Glu-B1c), and 5+10 (Glu-D1d) give a good quality score of 9, and subunits 2* (Glu-A1b), 7+8 (Glu-B1b), and 5+10 (Glu-D1d) give the maximum quality score of 10. Varieties from Finland have a low variability for HMW-glutenin alleles. The frequency of alleles encoding the subunits 2* at Glu-A1, 7+8 at Glu-B1, 2+12 and 5+10 at Glu-D1 is high. Finnish cultivars have a high quality score of 8 (Sontag et al. 1986) and have been strongly influenced by spring wheat cultivars from Russia and Canada (Sontag-Strohm and Juuti 1997). The limited number of combinations of HMW-glutenin subunits amongst Finnish wheats is probably due to the long tradition of breeding and growing wheat primarily for making bread (Sontag et al. 1986). This knowledge could be used to find lines for our breeding program. Wheat breeding will benefit greatly from the development of new common wheat genotypes with high adaptability to the local growth conditions by using germ plasm with wide genetic diversity.

References.

• Koppe R, Ingver A, and Küüts H. 1998. The results of co-operation about spring wheat breeding between Estonia and Finland. In: Genetics and Breeding of Cereal Crops. Harku, 56-63 (in Estonian).
• Koppel R and Ingver A. 1999. The objectives of spring wheat breeding programme at the Jõgeva Plant Breeding Institute. In: Cereal Breeding: Achievements and Prospects for Improvement. Jõgeva 14-15.
• Payne PI, Corfield KG, Holt LM, and Blackman JA. 1981. Correlations between the inheritance of certain high molecular weight subunits of glutenin and bread making quality in progenies of six crosses of bread wheat. J Sci Food Agric 32:51-60.
• Payne PI and Lawrence GJ. 1983. Catalogue of alleles for the complex gene loci, Glu-A1, Glu-B1, and Glu-D1 which code for high-molecular-weight subunits of glutenin in hexaploid wheat. Cereal Res Commun 11(2):9-35.
• Sontag T, Salovaara H, and Payne PI. 1986. The high-molecular-weight glutenin subunit compositions of wheat varieties bred in Finland. J Agric Sci Finland. 58:151-156.
• Sontag-Strohm T and Juuti T. 1997. Association between gliadin and glutenin subunit alleles and baking quality in spring wheat cultivars and breeding lines grown in Finland. Acta Agric Scandinavica, Sect B Soil and Plant Sci 47:106-111.

New, advanced, spring wheat varieties.

Recent advanced spring wheat lines or varieties include Heta and Manu from Estonia, Ulla from Finland, and Satu and Tjalve from Sweden.

Location of resistance gene to powdery mildew in common wheat introgressive line SMT43.

H. Peusha, T. Enno, and O. Priilinn.

The introgressive wheat line SMT43 was selected in the progeny of crosses between the hexaploid wheat cultivar Saratovskaya 29 and tetraploid hybrid F1 (T. militinae/T. timopheevii subsp. timopheevii). Pentaploid hybrid F1s were backcrossed to the female parent for 3-4 generations to restore fertility with simultaneous selection of resistant plants on infection background. The test for powdery mildew resistance was made on segments of primary leaves of host plants. The powdery mildew isolate No. 6 (avirulence/virulence formula Pm1, Pm2, Pm3a, Pm6, Pm1+Pm2+Pm9, Pm16/Pm3b, Pm3c, Pm3d, Pm3e, Pm4a, Pm4b, Pm5, Pm8) used for the inoculation was selected from single spore progeny and was kindly provided to us by Dr. F. Felsenstein. The methods used for inoculation of the leaf segments and the disease assessment were previously described by Lutz et al. (1992) and Peusha et al. (1996). A set of the 21 monosomic lines of Chinese Spring was used in a monosomic analysis of the line SMT43 to determine the chromosomal location of the resistance gene.

The F2 progenies from crosses between the Chinese Spring monosomic lines and the introgressive line SMT43 showed a segregation ratio of 3:1 resistant to susceptible plants in 20 cross combinations after inoculation with powdery mildew isolate No. 6 (Table 1). These data indicate that SMT43 possesses a single, dominant gene conferring resistance. The progeny from the cross with monosomic 6B deviated significantly (P < 0.01, c2 = 7.142) from the expected ratio, indicating that a dominant resistance gene for powdery mildew is located on this chromosome.

Several examples of transfers of genes for resistance from cultivated and wild relatives of Triticum to commercial hexaploid wheat have been reported. McIntosh (1998) communicated that chromosome 6B carries resistance genes Pm11, Pm12, and Pm20. Genes Pm11 and Pm12 are derived from T. aestivum subsp. compactum and Ae. speltoides (Miller et al. 1988; Jia et al. 1996; McIntosh 1998), respectively. Gene Pm20 was transferred to common wheat from the cultivated rye Prolific (Friebe et al. 1994).

We believe that this new resistance gene located on chromosome 6B is not identical to any of the above mentioned genes, because it evidently was introduced to line SMT43 from T. timopheevii subsp. timopheevii.

The participation of chromosome 6B in reciprocal translocations in disease-resistant introgressive lines 146-155-T and SMT34, derivatives of T. timopheevii subsp. timopheevii and T. militinae, was confirmed earlier by C-banding analysis of mitotic metaphase chromosomes (Badaeva et al. 1995).

The dominant powdery mildew resistance gene Pm27, located on chromosome 6B in the introgressive line 146-155-T, was introduced from T. timopheevii subsp. timopheevii. RFLP and microsatellite analyses detected a T. timopheevii subsp. timopheevii translocation on the 6B common wheat chromosome (Järve et al., in press).

Our phytopathological analysis revealed different reactions of wheat lines 146-155-T and SMT43 after inoculation with the available collection of powdery mildew isolates. However, to verify that gene Pm27 of line 146-155-T is not the resistance gene located on chromosome 6B in line SMT43, we intend to test for allelism.

The method of cytogenetical analysis of microsporogenesis in the F1 hybrid plants was described previously by Enno et al. (1998). The cytological analysis of meiosis in the monosomic F1 hybrids 'Chinese Spring monosomic / SMT43' has revealed less regular chromosome pairing at metaphase I compared with the disomic hybrid F1 (Table 2). Associations between the chromosomes in the monosomic hybrids were rather weak, resulting in premature disjoining of the bivalents and an increase in the number of additional univalents. The mean number of bivalents was lower and that of univalents higher in crosses with the monosomic lines of chromosomes 3B and 7B. The mean number of bivalents was greater and that of univalents lower in monosomic hybrids of chromosomes 1B and 5D. In these crosses, the mean number of chiasmata was also the highest, 35.6 and 35.3, respectively. Chromosomes 3B and 7B decreased pairing, whereas pairing increased with chromosomes 1B and 5D. In the monosomic hybrids F1, different frequencies of multivalent associations at MI were observed. Hybrids F1 with monosomic lines 2B and 6B had the trivalent configurations without univalents, and, consequently, these chromosomes were involved in the reciprocal translocations. On the basis of the frequencies of trivalent formation, we can assume that introgressive line SMT43 has the chromosomal interchange 2B/6B in relation to Chinese Spring.

References.

• Badaeva ED, Badaev NS, Enno TM, Zeller FJ, and Peusha HO. 1995. Chromosome substitutions in progeny of hybrids Triticum aestivum x Triticum timopheevii resistant to brown rust and powdery mildew. Russian J Genet 31(N 1):75-77.
• Enno T, Peusha H, Timofeyeva L, Tohver M, Yakobson I, and Priilinn O. 1998. Identification of chromosomal translocations in common wheat, derivative of Triticum timopheevii. Acta Agron Hungarica 46(N 3):209216.
• Friebe B, Heun M, Tuleen N, Zeller FJ, and Gill BS. 1994. Cytogenetically monitored transfer of powdery mildew resistance from rye into wheat. Crop Sci 34:621-625.
  Jia J, Devos KM, Chao S, Miller TE, Reader DM, and Gale MD. 1996. RTLF-based maps of homoeologous group-6 chromosomes of wheat and their application to the tagging of Pm12, a powdery mildew resistance gene transferred from Aegilops speltoides to wheat. Theor Appl Genet 92:559-565.
• Järve K, Peusha HO, Tsymbalova J, Tamm S, Devos KM, and Enno TM. 2000. Chromosomal localization of the translocation conferring powdery mildew resistance in a T. timopheevii-derived introgressive wheat line. Genome (in press).
• Lutz J, Limpert E, Bartos P, and Zeller FJ. 1992. Identification of powdery mildew resistance genes in common wheat (Triticum aestivum L.). Czechoslovakian cultivars. Plant Breed 108:33-39.
• McIntosh RA. 1998. Catalogue of gene symbols for wheat. In: Proc 9th Internat Wheat Genet Symp (Slinkard AE ed), Univ Extension Press, Saskatchewan, Canada. 5:1-235.
• Miller TE, Reader SM, Ainsworth CC, and Summers RW. 1988. The introduction of a major gene for resistance to powdery mildew of wheat, Erysiphe graminis f. sp. tritici, from Aegilops speltoides into wheat, Triticum aestivum. In: Cereal breeding related to integrated cereal production. Proc EUCARPIA Conference (Jorna ML and Slootmaker LAJ eds), Wageningen, the Netherlands. Pp. 179-184.
• Peusha H, Hsam SLK, Enno T, and Zeller FJ. 1996. Identification of powdery mildew resistance genes in common wheat (Triticum aestivum L. em. Thell.) VIII. Cultivars and advanced breeding lines grown in Finland. Hereditas 124:91-93.

Publications.

• Ingver A. 1998. Spring wheat collection trial as initial material in breeding. Master of Science Thesis. Estonian Agricultural University. Jõgeva 93 (in Estonian).
• Ingver A, Koppel M, Koppel R, and Küüts H. 1999. Biological and cytogenetical peculiarities of spring wheat cultivars and interspecific hybrids. II. Disease and lodging resistance and length of growing period of spring wheat cultivars and breeding lines. J Agric Sci. X(2), Tartu, 123-128 (in Estonian).
• Ingver A and Koppel R. 1998. The activity of enzyme a-amylase and its influence to the grain quality of spring wheat. In: Genetics and Breeding of Cereal Crops, Harku. Pp. 89-96 (in Estonian).
• Ingver A and Koppel R. 1998. Spring wheat breeding for sprouting resistance in Estonia. In: Proc 8th Internat Symp Pre-harvest Sprouting in Cereals. Detmold. Pp. 149-155.
• Ingver A, Koppel R, Koppel M, Tamm Ü, and Tamm I. 1998. Results of cereal breeding at the Jõgeva Plant Breeding Institute. In: Cereal Crop Breeding and Grain Quality, Latvia, Dizstende. Pp. 9-11.
• Koppel R. 1999. The comparison of spring wheat breeds. Master of Science Thesis, Estonian Agricultural University, Jõgeva. Pp. 108 (in Estonian).
• Koppel R, Ingver A, and Küüts H. 1998. The results of co-operation about spring wheat breeding between Estonia and Finland. In: Genetics and Breeding of Cereal Crops, Harku. Pp. 56-63 (in Estonian).
• Koppel R and Ingver A. 1999. Falling number of spring wheat. In: From Science to the Field and Garden, Jäneda. Pp. 91-93 (in Estonian).
• Koppel R and Ingver A. 1999. The objectives of spring wheat breeding programme at the Jõgeva Plant Breeding Institute. In: Cereal Breeding-Achievements and Prospects for Improvement, Jõgeva. Pp. 14-15.
• Tohver M. 1998. The storage proteins of hexaploid wheat and their relation to bread-making quality. In: Food and Nutrition. VI. Tallinn Technical University, Tallinn. Pp. 68-75.
• Tohver M. 1998. The possibilities of estimating kernel quality at an early stage of breeding. In: Genetics and Breeding of Cereal Crops, Harku. Pp. 82-88 (in Estonian).
• Tohver M, Täht R, Kann A, and Rahnu I. 1999. Gel electrophoretic investigations of seed storage protein fractions in triticale. In: Food and Nutrition. VII. Tallinn Technical University, Tallinn. Pp. 77-92.