ITEMS FROM SERBIA
ARI `Serbia' Center for Small Grains
Kragujevac, S. Kovacevica 31, 34000 Kragujevac, Serbia.
The Center for Small Grains `Kragujevac' is a research unit of the Agriculture Research `Serbia'B Belgrade. The actual program of scientific work of the Institute is the creation of new high yielding and high quality cultivars of wheat and other small grains.
Bistrica - new Yugoslav winter wheat cultivar.
M. Pavlovic, M. Kuburovic, and V. Zecevic.
The winter wheat cultivar Bistrica was created by crossing cultivars `Una x KG-56' in 1984 at the Center for Small Grains - Kragujevac. By gene recombination, a new wheat cultivar was obtained with high yield, good technological quality, and low stem, suitable for growing on forable soils. This cultivar was selected by the pedigree method and included in microtrials of the Federal Approval Commission. During a 3-year period, the cultivar was tested in microtrials at five locations, compared to the check cultivars, Jugoslavija and Partizanka, and approved as a new winter wheat cultivar. Breeders of this cultivar are Dr. Miroslav Kuburovic and M.Sci. Milanko Pavlovic.
The cultivar Bistrica has white, smooth ears and red grain colour. According to botanical classification, Bistrica belongs to Triticum aestivum ssp. vulgare var. lutescens. This is a middle-early cultivar with a strong stem, high lodging resistance, and low temperature tolerance (Table 1). A very productive cultivar, the maximal gene yield in locality Pec in 1991 was 9,380 kg/ha. The average grain yield during the experimental time was 7,550 kg/ha, significantly higher than in both check cultivars (Table 2). On the basis of the parameters of technological quality (Table 3), Bistrica belongs to quality class I and quality group B2. In Bistrica, yield was 85.3 kg/ha and the 1,000 kernel weight was 29.4g. On the basis of the results from the microtrials of Federal Commission for cultivar approvement, the commission approved Bistrica as a new winter wheat cultivar.
References.
Borojevic S. 1981. Principles and Methods of Plant Breeding. Novi Sad.
Borojevic S and Potocanac J. 1966. Development of Yugoslav programme on creation of high yielding wheat cultivars. 5th Yugoslav Symp Sci Res Work Wheat. Novi Sad. Contemp Agric 11-12:7-35.
Table 1. Some traits of the cultivar Bistrica in comparison with the check cultivars.
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Cultivar Plant height Freezing Lodging 1,000 kernel Yield
(cm) (%) (0-9) weight (kg) (kg/ha)
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Bistrica 87.72 96.67 0.90 29.4 85.3
Partizanka 87.90 100.00 0.50 28.9 86.1
Jugoslavija 90.85 96.67 0.60 32.8 85.7
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Table 2. Average grain yield of the cultivar Bistrica and check cultivars (t/ha)
during the years 1991-1993.
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Year Cultivars LSD LSD
Bistrica Partizanka Jugoslavija 0.05 0.01
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1991 8.013 6.442** 7.504** 354 467
1992 7.765 7.332* 7.295** 351 463
1993 6.872 6.715 6.844 399 527
Average 7.550 6.830** 7.214** 220 290
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Table 3. Some parameters of quality of flour and bread in the cultivar Bistrica compared to the check
cultivars.
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Character Cultivar Novi Sad Zajear Cross LSD LSD
0.01 0.05
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Raw proteins (%) Bistrica 15.2 16.6 15.9 - -
Partizanka 15.1 16.0 15.6 0.94 1.28
Jugoslavija 14.8 6.4 15.6 - -
Sedimentation (ml) Bistrica 43.0 64.0 54.0 - -
Prtizanka 61.0 66.0 64.0 - -
Jugoslavija 38.0 41.0 40.0 - -
Flour content (%) Bistrica 79.5 78.1 78.8 - -
Partizanka 78.6 77.4 78.0 2.23 3.03
Jugoslavija 81.3 78.2 79.8 - -
Yield of bread g/100 g flour Bistrica 134.4 134.4 134.4 - -
Partizanka 136.7 136.4 135.6 2.78 3.78
Jugoslavija 135.9 136.2 136.1 - -
Bread volume ml/100 g flour Bistrica 527.0 479.0 503.0 - -
Partizanka 552.0 562.0 557.0 - -
Jugoslavija 537.0 557.0 547.0 - -
Crumb value Bistrica 4.5 2.9 3.7 - -
Partizanka 5.0 4.7 4.9 - -
Jugoslavija 5.7 5.9 5.8 - -
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The relationship between gliadin alleles and wheat resistance to leaf rust, Puccinia recondita f. sp. tritici.
Desimir Knezevic, Miroslav Kuburovic, Milanko Pavlovic, and Ivana Bozinovic.
The acid PAGE patterns of the endosperm alcohol-soluble proteins of common wheat (Triticum aestivum L.) showed a high degree of polymorphism. These proteins were analyzed by acid PAGE and genetically interpreted. Differences among cultivars were expressed according to resistance to Puccinia recondita f. sp. tritici. The connections between alleles of the gliadin loci and degree of resistance to P. recondita f. sp. tritici were analyzed. The loci Gli-A1a, Gli-B1g, Gli-D1k, Gli-A2a, Gli-B2h, and Gli-D2g showed significant relationships with higher leaf rust resistance than other alleles determined on each of six loci.
Introduction. The genes controlling gliadins were located on the short arms of the 1A, 1B, 1D, 6A, 6B, and 6D chromosomes. Each gene group displays allelic variation that is detectable by one-dimensional polyacrylamide gel electrophoresis (PAGE). Gliadins are the main constituents of kernel proteins and have some rheological, but predominantly nutritional, importance (Metakovsky et al. 1990). The alleles of gliadins seem to be associated with the biological properties of wheat varieties. In wheat, gliadin proteins also have been suggested as linked markers to many agronomically important traits such as heading time (Lafiandra et al. 1987); frost hardiness (Sozinov and Poperelya 1980); disease resistance (Poperelya and Babajantz 1978; Sasek et al. 1985; Howes 1986); and technological quality (Sozinov and Poperelya 1980; Branlard and Dardevet 1985; Metakovsky et al. 1990; Reddy and Appels 1991; Knezevic et al. 1993). This paper provides an analysis of relationships between gliadin alleles and leaf rust resistance in 49 Yugoslav wheat cultivars.
Materials and methods. Grain samples of the 49 wheat varieties (T. aestivum) were obtained from the original wheat breeding centers. From single seeds, gliadins were extracted from wheatmeal with 70 % (v/v) ethanol at 40 C. Gel electrophoresis was performed in 8.33 % polyacrylamide in a vertical slab for 2.5 to 3 h at 550 V and 10 C (start) to 25-30 C (end) in an aluminum lactate buffer at pH 3.1, according to methods of Novoselskaya et al. 1983.
At least 20 single kernels were analyzed for each cultivar. Gliadin alleles were determined on the basis of gliadin block identification, and the designation of alleles was according to the nomenclature of Metakovsky (1991). Intensity of infection were evaluated using Cobbs scale.
Results and discussion. This investigation showed differences between wheat cultivars according to resistance to leaf rust. Each wheat cultivar also differed in allele composition of its gliadin loci. The results indicate different, but not statistically significant, important alleles at the same gliadin locus for leaf rust resistance (Table 1). The highest connection with leaf rust resistance was expressed in the gliadin alleles: Gli-A1a, Gli-B1b, Gli-D1k, Gli-A2a, Gli-B2h, and Gli-D2g. The connection between gliadin alleles and leaf rust resistance is likely because both genes are very close on the same chromosome. It is well known that gene Lr21, which confers resistance to P. recondita, is derived from T. tauschii as a partially dominant trait (Hart et al. 1992). This gene is located on chromosome 1D and has been mapped relative to storage protein loci (Gli-1 and Glu-3 loci) and glume color on the short arm (Jones et. al. 1990).
Gliadin protein markers can be applied to the solution of cultivar problems in plant breeding. Markers that flank a gene controlling a trait of agronomic interest can be used to track the trait in genetic crosses, i.e., to perform marker-assisted selection. However, the advantages of marker-assisted selection are expected to be maximized in breeding programs that involve quantitative traits, where the efficacy of genotypic assays can be much higher than that of phenotypic ones.
Table 1. Intensity of infection in wheat cultivars and connection between gliadin (Gli) alleles and
leaf rust resistance.
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Allele Allele Allele Allele
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A1a 12.8% A1b 15.2% A1c 21.8% A1f 13.4% a>f>b>c
B1g 21.6% B1b 12.3% B11 15.1% B1e 24.8% b>l>g>e
D1a 14.9% D1b 15.6% D1f 16.3% D1k 13.6% k>a>b>f
A2e 13.7% A2b 15.7% A2g 17.6% a>b>g
B2p 13.1% B2b 15.6% B2h 9.6% B2o 23.8% h>p>b>o
D2a 15.3% D2b 11.5% D2m 20.1% D2g 6.6% g>b>a>m
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Table 2. Frequencies of alleles in analysed wheat cultivars.
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A1 % B1 % D1 % A2 % B2 % D2 %
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b 38 b 43 b 49 b 24 b 42 b 41
f 13 g 9 f 13 g 40 o 12 g 2
c 12 e 13 a 19 e 26 p 8 a 33
a 31 1 28 k 16 - -- h 15 m 10
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*A higher number of Gli alleles were identified but with low frequency and they were not included for statistical analysis.
Conclusion. The wheat cultivars showed different resistance to P. recondita. The different relationships between gliadin alleles and leaf rust resistance were established. The higher resistance to leaf rust in cultivars that possessed the Gli-D2g allele is connected with their close location to some of Lr genes. In the breeding program, the gliadin alleles could be used as markers to estimate the genetic contribution of each of two parents to each of their progeny.
References.
Branlard G and Dardevet M. 1985. J Cereal Sci 3:329-343.
Hart GE, Gale MD, and McIntosh RA. 1992. Proc 3rd Public Workshop ITMI. Pp. 32-46.
Howes NK. 1986. Can J Genet Cytol 28:595-600.
Jones SS, et al. 1990. Genome 33:937-940.
Knezevic D, Vapa L, and Javornik B. 1995. Proc 8th Int Wheat Genet Symp, Beijing. Pp. 1203-1208.
Koval SF, et al. 1986. Selskhohoz Biol 2:31-36.
Lafiandra D, et al. 1987. Plant Breed 99:333-335.
Lagudah ES, The T, Appels R, Eastwood R, McIntosh RA, and Chandramorhan S. 1992. Proc 3rd Public Workshop ITMI. Pp. 26-28.
Metakovsky EV, et al. 1990. Aust J Agric Res 41:289-306.
Metakovsky EV. 1991. J Genet Breed 45:325-344.
Novoselskaya AY, et al. 1983. Cytol Genet Kiev 17:45-49.
Poperelya FA and Babajantz. 1978. Dokl VASHNIL USSR 6:6-7.
Reddy P and Appels R. 1991. In: Gluten proteins 1990. Winnipeg, Canada. Pp. 520-526.
Sasek A, et al. 1985. Scientia Agric Bohemoslovaca 17:243-254.
Sozinov AA and Poperelya FA. 1980. Ann Technol Agric 29:229-245.
ITEMS FROM SOUTH AFRICA
Small Grain Centre, Grain Crops Institute
Bethlehem, South Africa.
Winter wheat breeding.
H. A. van Niekerk, H. Knobel, N. Warburton, D.J. Exley, W. Miles, and R. Pretorius.
In addition to the two cultivars with Russian wheat aphid resistance that are already being grown commercially, another three resistant cultivars may be added this year. These lines, with the proposed names in parentheses, are: T92/20 ('Oranje'), T92/12 ('Molopo') and T92/22 ('Selati').
Nicola Warburton has joined the programme as a replacement for Brooks Coetzee who joined Sensako as a maize breeder.
Spring wheat breeding.
H.A. van Niekerk, F. Koekemoer, A. Grobbelaar, T.G. Paxton, S. Jordaan, R. Britz, F. Groenewald, and S. Pelser.
The part of the programme to develop cultivars for the high potential environments is making progress with the development of Russian wheat aphid-resistant lines. This year, lines with resistance will be evaluated in the F6 generation. The new releases, namely `Kariega' and `Marico', were produced commercially for the first time last year. Most of the farmers that produced these cultivars were satisfied with their performance. These two cultivars and some other breeding lines were forwarded to CIMMYT, because they want to increase the NARS germplasm portion in their international trials.
In the dryland portion of this programme, eyespot-resistant lines will be evaluated extensively for the first time this season.
International nurseries and germplasm collection.
I.B.J. Smit, T. Bredenkamp, and A. Otto.
This programme continues to be a major source of genetic variability. A total of 1,966 wheat, triticale, and barley entries from four winter and 10 spring international nurseries and trials was evaluated. Even though plots were irrigated, conditions of severe drought were such that a disease-free environment was obtained. Apart from powdery mildew, practically no infections were observed. This is quite unusual.
T. Bredenkamp has replaced Francois Groenewald as officer in charge of the germplasm collection.
Production and 1993 crop conditions.
J.L. Purchase, A. Barnard, C.G. Burbidge, T.F. Walsh, H.J.L Potgieter, A.H. Botha, M. Maritz, C.J.S. Nel, H.S.C.A. van der Merwe, W. van der Westhuizen, H. Hatting, J. du Plessis, and H. du Plessis.
The three major wheat producing regions of South Africa are the Western Cape Province (Mediterranean climate), Orange Free State (summer rainfall region), and the irrigation areas along the major rivers (aric region). High-yielding spring types generally are planted in the Western Cape and under irrigation, whereas winter and intermediate wheat types dominate production under dryland conditions in the Orange Free State. The total wheat crop for the 1993-1994 season, as estimated by the Wheat Board, should amount to 1.6 million metric tons. This is well below the long-term average and will not meet the demand of approximately 2.1 million metric tons. Conditions in the South Western Cape were fairly favourable, especially in the Southern Cape, where near-record yields were achieved, but drought in July and August in parts of the Swartland limited yields. In the Orange Free State, severe drought conditions were experienced that limited yields considerably and, also, led to a poor crop for the country in general. However, the yields under irrigation were up considerably, because of much cooler temperatures that were experienced early in the season leading to excellent tillering and high yields.
Cultivar performance in the Western Cape. In the Western Cape, the cultivar `Palmiet' still accounts for the major part of the production, even though it was released as far back as 1983. Although recently released cultivars such as `Nantes' and `Adam Tas' are also high-yielding and have various desirable agronomic and quality traits, they do not tend to have the yield stability of Palmiet. Two new cultivars bred by Sensako, i.e., `SST55' and `SST38', are showing some promise.
Cultivar performance in the Orange Free State. Because of the relatively large variation that exists in climatic conditions and soil types in this region, a fairly extensive cultivar evaluation programme is followed. In the OFS, a range of diverse cultivars is planted, ranging from spring to winter types and including a number of F1 hybrids. Due to unfavourable conditions during the past season that led to fairly heavy infestations of the devastating Russian wheat aphid (RWA), the new RWA-resistant cultivars generally outperformed the older, susceptible cultivars by about 10 % or more. The cultivar `Tugela-DN' performed especially well.
Cultivar performance under irrigation. An intensive spring wheat cultivar adaptation programme is run in five irrigation areas, which vary in climatic conditions. The objective of the programme is to characterize commercial cultivars and newly released lines suited to irrigation in terms of yield potential, yield stability, and agronomic characteristics. The cultivars Palmiet and `Gamtoos' were found to be well adapted over a wide range of environmental conditions, whereas certain cultivars, for example `Harts' and `T4', show very specific adaptation. However, `Gamtoos' is a cultivar with poor baking quality. Marico and Kariega have been developed to replace the latter cultivar in terms of baking quality, while still maintaining high yield potential and yield stability.
Southern African Wheat Evaluation and Improvement Nursery (SARWEIN). The SARWEIN programme was established in 1976, at the instigation of Dr. Norman Borlaug, during a visit to Southern Africa. Nurseries of well adapted germplasm are made available to several Southern African countries, including Lesotho, Swaziland, Namibia, Malawi, Mozambique, and Botswana. Cultivars selected from the nurseries already have made a significant impact on the limited wheat production in most of these countries. At present, negotiations are underway to expand the programme to function under the auspices of CIMMYT, with all the countries of the Southern African Development Community (SADC).
Preharvest Sprouting. A significant part of the South African wheat crop is lost to preharvest sprouting. Cultivars were evaluated over a number of environments to assess the expression of resistance over environmental conditions encountered during the grain filling period. Principal component analysis was used to examine the underlying source of variability in preharvest sprouting. Canonical correlation analysis was used to determine to what extent environmental factors were responsible for the variation in preharvest sprouting. Field evidence of effects of the environment during grain development on eventual seed germinability was quite strong. A study to investigate the nature of dormancy in South African wheat cultivars was carried out. The results demonstrated that the level and duration of dormancy differed between cultivars and that different mechanisms of resistance occur in different cultivars.
Seed physiology. The seed physiology programme is concerned mainly with factors affecting germination and coleoptile length. Because of the recent inclusion of wheat under the Plant Improvement Act of 1976, the demand for the evaluation of seed quality has lead to the establishment of a seed laboratory.
Personnel. J.C.H. de Wet and A.J. Rautenbach, unfortunately, left us during the past year, but have been replaced by D. Armstrong and Frederieke Bruin, respectively.