ITEMS FROM RUSSIA
Agricultural Research Institute for South-East Regions
7 Toulaikova Str, Saratov, 410020, Russia.
New spring durum wheat cultivar `Ludmila'.
N.S. Vassiltchouk (Durum wheat breeding program leader), V.I. Kassatov, V.M. Popova, and S.N. Gaponov.
The early, strong gluten cultivar, Ludmilla, is recommended for Saratov region farmers growing durum wheat under conditions characterized by middle and late summer droughts. It is tall, but resistant to lodging because of the strong straw. Ludmilla yields higher than Krasnokoutka 6, Saratovskaya 57, and Bezentchoukskaya 139 and equal to Saratovskaya zolotistaya and Saratovskaya 59. Test weight is higher when compared with all check varieties. The yellow pigment content in the grain is near that of Krasnokoutka 6 and Bezentchoukskaya 139, but less than that of Saratovskaya zolotistaya and Svetlana. Protein content is close to that of Saratovskaya 57, Saratovskaya 59, and Bezentchoukskaya 139 and slightly less than that of Krasnokoutka 6 and Saratovskaya zolotistaya.
Selection for barley yellow dwarf virus.
N.S. Vassiltchouk, V.I. Kassatov, V.M. Popova, and S.N. Gaponov.
Until 1994, barley yellow dwarf virus (BYDV) had not attracted much attention in the southeastern part of Russia. Since 1994, severe losses have been observed in the spring bread and durum wheat fields in the Volga river regions. In some fields, we observed yield losses as high as 60-70 % in such popular cultivars as Krasnokoutka 6, Bezentchoukskaya 139, and Saratovskaya 57. Of course, although not good for grain production, this extremely severe natural infection allowed wheat breeders to select for tolerant lines within their different nurseries. We have already selected advanced breeding lines with tolerance to BYDV: D-2029, D-2030, D-2040, D-2017, D-2036, D-2045, D-2046, D-2052, and D-2054. These lines will be involved further in our durum breeding program for BYDV tolerance.
Sprouting influence on durum wheat quality.

N.S. Vassiltchouk, V.I. Kassatov, V.M. Popova, and S.N. Gaponov.
In some wet years, for instance 1989, 1990, and 1993, sprout damage was a serious quality problem in durum wheat in Saratovoblast. Research of sprouting influence on durum wheat quality was initiated. Preliminary investigations under natural conditions in wet, 1990 and 1993, and dry, 1991 and 1992, years were carried out on the white grain durum wheat varieties: Saratovskaya 57, Svetlana, and Saratovskaya zolotistaya. In both 1990 and 1993, the mean falling numbers and test weights of the three cultivars decreased significantly in comparison to the dry years, 1991-92 (Tables 1 and 2). Vitreousness decreased in 1990, particularly for the varieties Saratovskaya 57 and Svetlana. The other grain and semolina quality characters of 1,000 kernel weight, protein and ash content, semolina yellowness, SDS-sedimentation tests, and reological properties (mixing time), these decreased nonsignificantly. According to a preliminary study, the cultivar Saratovskaya zolotistaya appeared to be less sensitive to sprouting.
Table 1. Effect of weathering on falling numbers of durum wheat cultivars under natural conditions.
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Falling Number (sec.)
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Wet years Dry years
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Cultivar 1990 1993 Mean 1991 1992 Mean
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Saratovskaya 57 115 183 149 407 422 414
Svetlana 63 98 81 402 467 434
Saratovskaya zolotistaya 170 425 297 421 455 438
Mean 176 429

___________________________________________________________________ Table 2. Effect of weathering on the test weight of durum wheat cultivars under natural conditions.
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Test weight (g/l)
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Wet years Dry years
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Cultivar 1990 1993 Mean 1991 1992 Mean
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Saratovskaya 57 786 756 771 802 823 812
Svetlana 711 718 714 763 790 776
Saratovskaya zolotistaya 754 741 747 791 808 799

Mean 744 796
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Low chemical potential of water as a mutagen for callus-derived wheat somaclones.

S.V. Tuchin and Yu.V. Italianskaya.
The frequency of chromosome mutations induced by low water chemical potential (WCP) in callus culture media was determined for wheat somaclones. Embryogenic calli of spring bread wheat (cv. Ershovskaya 32) were cultured on media of various degrees of WCP depression. Three WCP depression levels (-9 J/mol; -18 J/mol; and -36 J/mol) were used. Thirty days later, plantlets were regenerated. Several cycles of sexual propagation were carried out and the gliadin electrophoretic spectra of the somaclones obtained. The frequencies of changed somaclones for gliadin spectra are presented in Table 3. A decrease in the WCP level in culture media from -9 J/mol to -36 J/mol caused an increase in the number of altered somaclones. Calli cultivation on a medium with a WCP depression of -9 J/mol resulted in minor changes in the gliadin spectra. A WCP depression of -18 J/mol and, especially, of -36 J/mol, induced considerable changes in bands controlled by loci of several chromosomes. In this case, somaclones had up to three altered chromosomes. The lowest WCP (-36 J/mol) stimulated strong changes in chromosomes of D genome. These results are in agreement with the findings on the role of the wheat D genome for adaptation to abiotic stress. A WCP depression of -36 J/mol is the critical level for callus survival and plant regeneration. The data obtained show that adaptation to lethal desiccation stress in bread wheat may be realized by means of increasing alterations in D-genome chromosomes.
Table 3. Water chemical potential (WCP) depression and the frequency of changes in the
gliadin spectra among wheat somaclones.
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Level of % Changed % Somaclones with changes
WCP depression somaclones in different genomes
(J/mol) _________________________________________

Genome A Genome B Genome D

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-9 45.5 0 36.4 9.1

-18 83.3 33.3 75.0 8.3

-36 93.8 43.8 6.3 81.8
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Thermodynamic analysis of water in tissues of wheat drought-resistant somaclones.

S.V. Tuchin.
Somaclones of wheat capable of an enhanced drought resistance were obtained by the exposure of cultured callus tissue to a low water potential medium. The mechanism for the higher level of tolerance in somaclones to drought is obscure and has received little study. In the present report, the thermodynamic characteristics of water in tissues of drought resistant somaclones were investigated. Callus cultures of the spring bread wheat cultivar, Ershovskaya 32 (E 32), were initiated from immature embryos on Linsmaer and Skoog's (LS) medium. Embryogenic calli were transferred to fresh LS media of various degrees of water chemical potential (WCP) depression. Two WCP depression levels (-9 J/mol, as a control, and -36 J/mol) were used. After 30 days, the water content, its activity, and the shift of the WCP in the cultured calli were measured. The calli adapted to a lower WCP showed reduced thermodynamic characteristics of water when compared with similar calli maintained on the control medium (Table 4). From the former callus cultures, plantlets were regenerated with a 10 % frequency as compared to the controls, which differentiated with a frequency of 75 %. After several cycles of sexual propagation, seeds of the somaclones (R6) and parent cultivar were germinated under osmotic stress imposed by a WCP depression in the medium of -25 J/mol. The thermodynamic characteristics of water in the adapted somaclones were increased in comparison to those in the nonadapted seedlings of parent cultivar. The plants of the somaclones (R7) and E 32, grown in soil under drought conditions, showed similar water patterns. The present results show that somaclones adapted in vitro regulate the thermodynamic characteristics of water in tissues when grown under desiccation stress. The plants of somaclones showed increased water content, activity, and WCP in comparison to those of the nonadapted parent cultivar.
Table 4. The thermodynamic characteristics of water in tissues of the wheat cultivar Ershovskaya 32 (E32).
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Cultivar/ Sample Kind Water Water WCP

somaclone of content, activity, depression,
desiccation % u.a. J/mol
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control -9 J/mol 89.8 0.9939 - 15.20

E 32 calli WCP depression 77.3 0.9650 - 88.41 -36 J/mol

E 32 7-day-old WCP depression 82.5 0.9735 - 64.04
Somaclones seedlings -25 J/mol 85.9 0.9785 - 50.30

E 32 growing land drought 81.5 0.9593 -109.86
somaclones plants conditions 86.5 0.9783 - 55.48
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The relationship between the acidification activity of roots, vegetation period, and stalk length.

A.N. Shigaev, V.A. Kumakov, and A.I. Peretyatko.
In experiments with 5- to 7-day-old, low-salt seedlings, varieties of wheat differing for ear emergence time, straw length, potassium absorption, and proton extrusion by intact roots (from a nutrient solution containing 1 mM K) were studied. Results showed that overall potassium (K) absorption and hydrogen (H) extrusion were correlated with indices characterizing the seedling dimension (biomass, root mass, and shoot mass). By these indices, the long-stalked varieties of wheat surpassed considerably the semidwarf types. An H-efflux is not connected with straw length, but is correlated with the time of ear emergence and the root/shoot ratio. With the use of factor analysis procedures, three factors that specified root activity and plant growth were determined. Factor No.1 (55.2 % of the variance) was interpreted as the factor of `plant organism power'. It determines root mass and shoot mass, summary potassium absorption, and proton extrusion. It is the extensive index that may be connected with dwarfing genes. Factor No. 2 (21.2 % of the variance) is the intensive index that characterizes the rhythm of the physiological and biochemical processes. It determines the vegetation period and, also, H-efflux and K-uptake, normalized on the fresh
root weight. The fact that H-efflux depends upon the rhythm of physiological and biochemical processes emphasizes the significance of this index for root activity determination. H-efflux may be used for the screening of genotypes with a high intensity of basal metabolism. Factor No. 3 (13.6 % of the variance) determines the root/shoot ratio.
Evolutionary aspects of potassium uptake and hydrogen efflux in wheat varieties.

A.N. Shigaev and V.A. Kumakov.
With the help of an evolutionary approach to the physiological attribute estimation of wheat varieties, one can reveal the regularity of their change in the selection process. In this work, the change of H-efflux and K-uptake by intact roots, from a solution containing 1 mM K, of 5- to 7-day-old, low-salt seedlings of 12 varieties of spring wheat were studied. These varieties were received from 1911 to 1980 in the selection centre of the Research Agricultural Institute of South-East Region (Saratov). In the comparison of H- and K-fluxes, we took notice of vegetation period differences. We determined that the seedlings of modern varieties had a more powerful root system and a higher root/shoot ratio. The increase in root mass was accompanied by a decrease in activity. All modern varieties yield to the older variety, Lutescens 62, for both K-uptake and H-efflux. Maximum differences in the percent to Lutescens 62 were 43 % in K-uptake and 68 % in H-efflux. Possibly, the decrease of specific root activity was determined by the decrease of root loading explained by the change in the root/shoot ratio. Obviously, in conditions of insufficient water, the principal factor that determines plant development is not high root activity, but a large root system.
The study of adaptive properties of winter wheat in ARISER.

A.I. Pryanishnikov.
The main condition for cultivation of winter wheat in Povolzhie is the reliability of overwintering crops. Investigations of this property in the winter wheat breeding laboratory are directed at the quantitative value of an environmental factor, the internal state of the plant, and their influence on winter hardiness. Six environmental vectors (V) were described by the biometrical analysis of meteorological data (1967-1993), which characterize the temperature regimes at the time when plants increase their tolerance to winter conditions. These vectors have high factoral loads in winter (V-1), autumn (V-2), spring (V-3), and conditions of hardening (V-4, V-5). The eight varieties in the study showed genotypical differences in the correlation of winter hardiness and absolute value of vectors. We found a weak dependence of overwinter degree to V-5 in older varieties, Hostianum 237 and Lutescens 230. We revealed a strong correlation of winter hardiness and V-2 in Saratovskaya 11 and also a high connection with V-4 in Hostianum 237 and Mironovskaya 808.
The appraisal of internal adaptive complex (1993-1994) showed three components (C) of resistance in 19 varieties. These components have high factoral loads with physical state of crown water in overwintering plants (C-1), quantitative electrolyte in cell sap (C-3), and membrane resistance of plant cells (C-2). The systemic analysis of the `genotype-environment' interaction permits the determination of the main limiting vector of the environment in a specific year and allows the screening of genotype reaction on different influencing external vectors.
Agronomic performance of a wheat cross using anther culture method.
A.I. Kusmenko, T.I. Dyatchouk, A.N. Galkin, K.F. Guryanova, V.A. Danilova, and T.K. Sotova.
The advantages of doubled-haploid (DH) lines are not limited to the time they save. One of the main advantages of the anther culture method is the possibility to screen the real breeding value of a cross. This performance is due to the ease of selecting desirable recombinants based on a direct choice for genetic characteristics and the possibility of fixing such combinations of characters, including adaptive values by segregation through selfing in classical breeding. This study evaluated the agronomic performance of a spring wheat cross using the anther culture method. From a cross of the advanced lines S-1976, as female, and S-1974, as male, 39 DH lines were recovered. From the 39 DH lines, 36 were eliminated after the first field multiplication based on their unsatisfactory characteristics (standability, disease, spike and grain size, and degree of lodging). Three lines were selected for replicated field experiments. The best of these, S-2045, showed a good combination of agronomic traits (Table 5). The remaining grain was used to select for superior recombinants by conventional breeding. After preliminary field trials of the F2 and F3, this cross was discarded. In conclusion, the anther culture method allows the wheat breeder to screen the real breeding value of a cross and make more efficient selections.
Table 5. Yield performance and grain quality of the doubled haploid advanced line, S-2045 (average 1991-1994).
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Baking quality
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Varieties Grain Loaf Texture Gluten Alveograph
yield volume score content volume
(t/ha) (cm3) (1-5) (%) (u.a.)
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S-2045 2.84 780 4.6 27.3 200

Saratovskaya 42 2.24 764 4.7 28.3 257
(as check)
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Change in isozyme patterns of osmotic stress-resistant callus in bread wheat.

Yu.V. Italianskaya.
In previous investigations, some drought-resistant wheat somaclonal variants were obtained through cell selection for osmotic stress resistance (with polyethyleneglycol as selective agent) and, thereafter, plant regeneration. Electrophoretic analysis of esterase and acid peroxidase revealed the specific appearance of new isozyme bands and the lack of several isozymes in drought-resistant somaclones as compared with the parental cultivars. In the present work, peroxidase and esterase isozyme patterns and activity were analysed in bread wheat calli selected for osmotic stress resistance and compared with those of control calli subcultivated on a medium devoid of selective agent. Although electrophoretic isozyme profiles differed considerably between calli and regenerated plants, selected calli were found to have some new bands, similar to those of drought-resistant somaclones. These data show that specific changes in peroxidase and esterase isozyme patterns seem to be reflections of some genetic variations that may be revealed at the early selection stages and, thus, allow for the discarding of unwanted somaclonal variation.
Agricultural Research Institute for South-East Regions
Laboratory of Genetics and Cytology, 7 Toulaikova Str, Saratov, 410020, Russia.

V.A. Krupnov, S.A. Voronina, S.N. Sibikeev, V.A. Elesin, and Yu.E. Sibikeva.

Virulence of leaf rust in bread wheat to Lr19.

The genetic pool of effective sources of rust resistance used in wheat (T. aestivum L.) breeding includes species of the genus Agropyron. The genes derived from Agropyron, Lr19, Lr19d, Lr29, LrAgi1, LrAgi2, and Lr38, are highly effective to pathotypes of P. recondita Rob. ex. Desm. But in 1994, in the Saratov and Orenbhurg districts of Russia, pathotypes were discovered that were virulent to these genes. The cause for the origin of pathotypes virulent to Lr19 is the widespread planting of the commercial cultivar L503, carrying Lr19, on more than 100,000 ha in the Volga and Ural regions. These pathotypes are also virulent on cultivars of Saratov breeding, carrying Lr19, Indis (Lr19d), and RL6097 (Lr38). The distribution of virulence on Thatcher near-isogenic lines with different Lr genes shows that most of the Lr genes are susceptible to these pathotypes of P. recondita. Exceptions were Lr lines with the genes Lr9, Lr23, Lr24, and Lr26. Different infection types were displayed when Mexican bread wheat cultivars, carrying widespread combinations of Lr genes, were inoculated with these pathotypes. From 10 Lr gene combinations, only four were highly effective. These Lr gene combinations include Lr23/26, Lr13/26, Lr23/26/34, and Lr26 + ?.
The effect of Lr genes in near-isogenic lines, sensitive and resistant to leaf rust, for yield and grain protein content.
The influence of Lr genes on yield and grain protein content of near-isogenic lines in field trials was studied. In 1993, under a severe leaf rust epidemic, gene Lr14a increased the yield to 812 kg/ha and had a grain protein content of 0.63 %. Lr23 was 1,140 kg/ha and 0.68 %, Lr19 had 1,090 kg/ha and 1.52 %, LrAgi2 had 1,664 kg/ha and 1.58 %, for yield and grain protein content, respectively. With no leaf rust epidemic, as in 1994, no significant differences for yield occurred between the Lr-sibs when compared to lr-sibs. However, the grain protein content in the Lr-sibs was significantly higher than the lr-sibs with the following results: the resistant isoline carrying Lr14a increased grain protein to 0.60 %, to 0.60 % with Lr23, 0.30 % with Lr19, and 0.62 % with LrAgi2, when compared to isolines susceptible to the pathogen. The 2-year mean for grain protein yield of the resistant isolines with the different Lr genes was also significantly higher than that of the susceptible isolines (24-71 %). Maximum differences were observed in pairs of isolines with the genes Lr19 and LrAgi2, derived from the genus Agropyron.