ITEMS FROM THE RUSSIAN FEDERATION

AGRICULTURAL RESEARCH INSTITUTE FOR SOUTH-EAST REGIONS

7 Toulaikova St., Saratov, 410020, Russia.

Performance of new durum lines under dry conditions.

N.S. Vassiltchouk, V.M. Popova, V.I. Kassatov, S.N. Gaponov, and G.I. Shutareva.

Weather during the vegetative period of spring durum wheats in the Volga river region was drier than normal for the southeastern part of Russia, in 1996. Total precipitation at Saratov for the season was 115 mm, compared to the long-term average of 139 mm. Under these conditions and without any fertilizer application, newly developed lines performed well with high gluten strength and high yellow pigment content (see data in Table 1).

The line D-2034 , named Valentina, is now in national testing. Lines D-2029 and D-2030 will be entered in national testing in 1997 after seed multiplication.

Table 1. Yield, 1,000-kernel weight, test weight, protein content, SDS-sedimentation test, and carotenoid pigment content of cultivars^* and promising new lines grown at Saratov, in 1996.

Laboratory of Genetics and Cytology

Agricultural Research Institute for South-East Regions, 7 Toulaikova St.,Saratov, 410020, Russia.

Reaction of red spring bread wheat near-isogenic lines to drought.

S.A. Voronina, V.A. Krupnov, and V.N. Semenov.

In previous communications (Krupnov et al. 1995, 1996), we reported about the positive effects of Lr genes and the prolamine locus on grain yield and protein content in NILs under relatively wet conditions. The reaction of NILs under heat and drought during 1995-96 is presented here. Only 15 mm of precipitation was recorded for the period from shoot-to-heading in 1995. In 1996, precipitation was absent from anthesis to the waxy-kernel ripening period. The temperature ranged from 32-38 C. The grain yield ranged from 0.654-1.396 T/ha in 1995 to 2.318-2.736 T/ha in 1996. Grain protein content varied from 16.05-17.10 % in 1995 to 15.68-16.87 % in 1996. The grain yield in 1995 was the lowest reported in the last 20 years. Sib lines did not differ significantly from each other for grain yield, 1,000-kernel weight, and grain protein content in 1995 and 1996. However, the grain protein contents in Lr sibs with Lr14a, Lr19, and Lr23, and prolamine-locus sibs were higher than those in their partners. Thus, the positive effect for grain protein content in Lr genes and prolamine sibs was expressed under heat and drought conditions.

Effects of R-genes in spring bread wheat for grain yield under drought conditions.

S.A. Voronina and V.A. Krupnov.

Only red-grained cultivars of bread wheat are grown in the Lower Volga Region. White-grained cultivars are now replacing red-grained cultivars. We produced NILs differing for R-gene alleles to study their effects. Ten pairs of NILs grown on black soils did not show any significant differences between R and r sibs for grain yield, 1,000-kernel weight, test weight, grain protein content, and loaf volume. Under heavy drought conditions of 1995-96, there were no differences between R and r sibs except in the L 503 (R) and L 504 (r) pair. The grain yield of L 504 (r) in 1995 was significantly higher than that of its red-grain sibs L 503 (1.978 T/ha and 1.222 T/ha, respectively; LSD = 0.190 T/ha). The causes of these differences are unknown.

Field and laboratory analysis of a leaf rust population of bread wheat in 1996.

S.N. Sibikeev, S.A. Voponina, and Yu.E. Sibikeeva (Laboratory of Winter Wheat Breeding).

The leaf rust epidemic during the 1996 growing season was not evaluated weekly. Nevertheless, infection types were noted on cultivars and lines of bread wheat with different Lr genes. Plants with genes derived from Agropyron species Lr19, Agi1, Agi2, and Agi3 (Sibikeev et al. 1995; Sibikeev et al. 1996) showed ITs = 3. A 0 IT was observed on an S55 NIL, which carries the Lr24 gene from Agent. The Lr-gene combinations Lr26 + Lr13, Lr26 + Lr23, and Lr26 + Lr23 + Lr13; and the combination of LrAgi1, LrAgi2, LrAgi3, and Lr19 with Lr 9, Lr23, Lr24, Lr25, and Lr26 were highly effective with ITs = 0.

The leaf rust population was collected in mid-July when air temperatures ranged from 30-32 C at the ARISE Region fields. Collections were made by researchers from the laboratories of genetics, winter wheat breeding, and plant immunity. Laboratory inoculations were made in the greenhouse at 20-22 C with the leaf rust inoculum and verified the efficiency of the above-mentioned Lr-gene combinations. Inoculations with three samples of leaf rust surprisingly did not discover the pp19 pathotype. The line with genes Lr19, LrAgi1, LrAgi2, and LrAgi3 showed ITs = 0. An IT = 3 was detected on cultivars susceptible to the pp19 pathotype (L503, L222, Agro58, and L1736) under field conditions. These cultivars showed an IT = 0 in the greenhouse at the same time. The sensitivity and subsequent decline of the pp19 pathotype to high temperature and low humidity during some weeks of July may help explain these results. Another explanation may be the reduction in viability of the pp19 leaf rust pathotype population during times of high viability of other pathotypes.

The range and severity of leaf rust on spring wheat in 1996.

O.V. Zubkova and V.A. Krupnov.

The first leaf rust pustules appeared on susceptible cultivars at the beginning of anthesis on 19 June, 1996. Afterward, dry, hot weather halted the development of an epidemic. The rust was supported mainly by dews at night. The lower leaves were most susceptible under these conditions. The level of disease was defined on cultivars and lines planted in full random blocks with four replications. Seven-row plots were used with an area of 7 m².

The number of pustules was counted four times, at intervals of 7 days, beginning on 30 June. Cultivars and lines with genes Lr19 and Lr23 showed the highest resistance to the local leaf rust pathotypes. The lowest level of disease among susceptible cultivars (lacking resistance provided by oligogenes) was in the old, local cultivar Lutescens 62.

The effects of genes for ear and leaf colors in durum wheat.

V.A. Elesin.

Lines differing separately for ear and leaf colors were studied in field yield trials during 1995-96. The durum wheat variety Hordeiforme was the source of genes for red ear, and the durum wheat Azerbaaidjansky mestny was the donor of genes for light-green leaves. The durum wheat cultivar Bezenchukskaya 139 was the recipient parent. The above-mentioned lines are not significantly different for heading date, plant height, and lodging resistance. Under the drought conditions of 1995-96, lines with white ears had a slightly higher grain yield then those with red ears A sib line with waxy leaves had a slight increase in grain yield compared to a sib line with light-green leaves (during 2 years the average increase was 0.07 T/ha). The increase in grain yield was the result of an increase in the number of tillers and 1,000-kernel weight.

Testing wheat-alien lines for bread- and spaghetti-making quality.

V.A. Krupnov, S.A. Voronina, I.N. Cherneva, and N.S. Vassiltchouk (Laboratory of Durum Wheat Breeding).

Bread wheat is sometimes used in the pasta-cooking industry in Russia. We investigated the possibility of using bread wheat-alien lines from crosses with durum wheat, T. dicoccum, Ag. intermedium, and Ag. elongatum for bread and spaghetti making. The grain yield of these lines in the drought of 1995 exceeded the grain yield of durum wheat cultivars by approximately threefold, with excellent baking and good pasta quality. The lines have the following characteristics: grain protein content of 16-18 %, wet gluten content (the first group of gluten strength) of nearly 50 %, and an alveograph W of 334-520 e.a. The lines were tested for color of spaghetti, spaghetti-breaking strength, overcooking, and the firmness of cooked spaghetti. The durum wheat cultivar Saratovskaya zolotistaya, having the best spaghetti-making quality, was used as the local check. Preliminary data show that all the lines were less than the local check only for spaghetti color. The spaghetti-breaking strength also decreased slightly. The above-mentioned lines were nearly the same as the check, or surpassed it on overcooking and firmness of cooked spaghetti. The most promising lines were L786, which contained germplasm from T. dicoccum; L773 (T. dicoccum, T. durum, and Ag. elongatum); and L2032 and 2033 (T. durum and Ag. elongatum). These preliminary investigations indicate the need for further work in this direction, because of the economical effects of using wheat-alien lines in bread baking and spaghetti making.

ALL-RUSSIAN INSTITUTE OF AGRICULTURAL BIOTECHNOLOGY - ARRIAB

Timiryazevskaya ul. 42, Moscow, 127550, Russia.

`Triticum durum x T. timopheevii' crosses as a way of cultivar nucleus reconstruction.

V.F. Kozlovskaya.

Nuclear discordance of wide hybrids is known to permit new mixogene formations. The possibility is of particular interest in macaroni wheats, because the production of aneuploid and chromosome addition lines is difficult. We have analyzed the cytology and fertility in the F₁BC₁ of `T. durum x T. timopheevii' hybrids.

Hybrid spikes at the appropriate meiotic stage were fixed in Newcomer's solution, and the chromosome stained using standard squash methods. The number of intergenomic substitutions was established according to univalent pairing in over 75 % of the PMCs. We analyzed 260 F₁BC₁ plants.

The expected chromosome number of the female gametes varied from 9 to 19. The average F₁ metaphase configuration was 9 bivalents and 10 univalents. Hypoploid egg cells were inviable. Euploids (n = 14) and hyperploids (n = 15 or 16) were observed at frequencies of 84.7 and 15.3 %, respectively. True euploids averaged 15 %. The pseudoeuploids consisted of mono-tetra-substituted cytotypes with frequencies of 14.8, 32.8, 17.5, and 3.6 %. The average meiotic index varied from 93.6 % (euploid) to 30.9 % in the tetra-substituted forms. The average F₁BC₁ fertility was 0.57 seeds/spikelet and varied greatly within the specific cytotypes. A highly positive correlation between seed set and meiotic index was found only for a group of di-substituted plants. Partially fertile plants with intergenomic chromosome substitutions were prevalent in the F₁BC₁, and may be the reason why a `T. durum x T. timopheevii' cross enables the reconstruction of the tetraploid wheat nucleus. Overcoming problems of female fertility possibly could improve `T. aestivum x T. timopheevii' hybrids at the first backcross.

RESEARCH INSTITUTE OF AGRICULTURE IN CENTRAL REGIONS OF NON-CHERNOZEM ZONE.

Nemchinovka 1, 143013 Moscow region, Russia.

Pollen irradiation method in a distant wheat hybridization.

I.F. Lapochkina and G.L. Yatchevskaya.

The lengthy process of developing initial breeding material (10-15 years) by routine methods encourages the search for more effective ones that may ensure introgression of valuable traits into the genome of common wheat (Yatchevskaya 1996; Lapochkina et al. 1996). Researchers have two main problems to solve: enabling homoeologous recombination between alien and wheat chromosomes and limiting the transfer of undesired traits from the wild species.

Material and methods. Genotypes that can suppress the Ph system of common wheat (ph1b mutant of Chinese Spring, Ae. speltoides, and wheatgrass clones) and pollen gamma-irradiation of donors have been used for many years to achieve the aforementioned introgression.

The gene pool of wild and synthetic forms used in crosses includes the donors of resistance to fungal diseases: Ag. intermedium, Ae. speltoides, Ae. triuncialis, Ae. recta, T. timopheevii, and T. Kiharae. Common wheat was the female parent, and the wild relatives were the pollinators. Hybridization was accomplished with advanced-pollen gamma-irradiation (⁶⁰Co 0.5, 0.75, 1.0, 1.5, 5.0, 10.0, 13.0, and 15.0 Kr with 500 r/min). Meiosis in the hybrid plant was analyzed on temporary acetocarmine-stained preparations. Samples were fixed in Newcomer's solution.

Results and discussion. The wide range of the irradiation doses and the large number of donor forms with different chromosome numbers allowed us to determine the regularities of wide hybridization accompanied by gamma-irradiation of a male pollen component.

1. Irradiation doses (0.5-0.75 Kr) can raise seed set in interspecific and intergeneric hybrids and sometimes may even overcome cross-incompatibility.

2. The direct influence of a radiation dose (up to 15 Kr) on the maternal seed morphology with feasible or slightly dented endosperm (the so-called `Gertwig's effect' first noted after irradiation of fish sperm; Pandey and Phung 1982) was determined. Hybrid and maternal-type kernels developed after irradiation with intermediate (1.5 Kr) and high (5.0-15.0 Kr) doses had a high tendency for very low germination (up to 100 % nongerminable). The data on plant survival are shown in Table 1.

3. Pollen irradiation used in hybridization leads to changes in chromosome number in F₁ plants. Among surviving F₁M₁ plants, we theoretically expected 2n; hypo- and hyperaneuploids; mosaics; plants of maternal types where 2n = 42, 42 + fragment(s), or 43; single haploids of common wheat; and in the combination `T. aestivum x Ae. speltoides' (10 Kr dose), asymmetric sexual hybrids (Table 2).

Table 1. The level of plant survival in a pollen-irradiation experiment involving `T. aestivum x Ae. triuncialis' hybrids.

Table 2. Variability of chromosome number in surviving matromorphic F₁M₁ plants of the cross `T. aestivum x Ae. speltoides' developed after pollen irradiation.

Matromorphic plants (2n = 42) did not differ significantly from the maternal common wheat varieties. Matromorphic plants with altered karyotypes appearing in this combination were rather rare for these intergeneric combinations and constituted only 0.07 % of the pollinated flowers.

The progeny of the matromorphic plants was analyzed in the second and following generations for their resistance to the mildew (natural conditions), the brown and stem rust (artificial infection) fungal pathogens, and some quantity and quality traits. Some of families did not show uniform resistance to diseases, plant height, or ear density, providing indirect evidence of genetic reconstruction of some matromorphic plants under pollen irradiation.

Asymmetrical sexual hybrids (2n = 49) were used later as a base for the development of Ae. speltoides addition, substitution, and translocation lines (Lapochkina 1996).

4. Chromosome pairing analysis at MI noted five F₁M₁ combinations with hybrid chromosome numbers, and the general outcome of irradiation doses between 0.5-1.5 Krs were established. The doses significantly raised the development of multivalents in cells, frequency of cells with multivalents, and chromosome number involved in the formation of multivalent associations (Table 3).

Table 3. Character of chromosome conjugation at MI of meiosis in 42-chromosome plants of `Chinese Spring x T. Kiharae' F₁ hybrids.

5. Variability of chromosome number and the presence of chromosome reconstruction in F₁M₁ plants influenced the development of form. Plants with hybrid chromosome numbers and aneuploids did not have the dominant traits of the pollinator in some cases, but the recessive traits of the maternal forms (limited transition of the pollinator's genetic material). Single plants of the maternal type that had some traits of the pollinator or new formations provided evidence concerning introgression of individual blocks of genes of the pollinator (as observed by K.K.Pandey (1978) on tobacco, but with much lower frequency). This knowledge will help to assess the effect of low doses of pollen irradiation on chromosome pairing and introgression of alien genetic material.

Conclusion. The effectiveness of low and high pollen irradiation doses was shown. In both cases, it was possible to develop material of common wheat with high resistance to the brown rust and mildew fungal pathogens. This pollen gamma-irradiation method overcomes the cross-incompatibility between species, raises hybrid seed set, influences chromosome pairing, and changes the genotypes of F₁M₁ hybrids. The effectiveness of the method first depends on the limitation of the pollinator's genetic material transition and on a form development shift nearer to the maternal genotype. Based on pollen irradiation data for other species and F₁ hybrid variability (Raquin et al. 1989), we suggest that these features generally cause biological irregularities in development in the progeny, providing broader possibilities for application of these methods for plant breeding.

References.

Lapochkina IF. 1996. Constant soft wheat lines collection development by adding of Aegilops speltoides chromosomes obtained on the basis of asymmetric sex hybrids 2n = 49. 5th Inter Wheat Conf, 10-14 June, 1996, Ankara, Turkey. p. 431-432.

Lapochkina I.F. et.al. 1996. Common wheat lines with genetic material from Aegilops speltoides Tausch. Russian J Genet 32 (12):1651-1656.

Pandey KK. 1978. Gametic gene transfer in Nicotiana by irradiated pollen. Genetica 49 (1):53-69.

Pandey KK and Phung M. 1982. "Hertwig effect" in plants: induced parthenogenesis through the use of irradiated pollen. Theor Appl Genet 62:295-300.

Raquin C et.al. 1989. Nucleus substitution between Petunia species using gamma ray-induced androgenesis. Theor Appl Genet 78:337-341.

Yatchevskaya G.L. 1996. Lines of common winter wheat with substituted chromosomes of Agropyron intermedium (Hjst) Beaw. carry genes resistant to mildew. 5th Inter Wheat Conf, 10-14 June, 1996, Ankara, Turkey. p. 168.

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