ITEMS FROM THE RUSSIAN FEDERATION

AGRICULTURAL RESEARCH INSTITUTE OF THE CENTRAL REGION OF NON-CHENOZEM ZONE
143026, Nemchinovka-1, Moscow region, Russian Federation.

 

A synthetic species Triticum X duelongatum Pol. and a new line Triticum X Agropyrotriticum Cicin. [p. 103-104]

L.V. Poleva.

As a result of long-term work on hybridization of T. durum and T. aestivum with Th. elongatum (2n = 10x = 70), a wide diversity of hexaploid and octoploid wheat-Agropyron genotypes was developed, including a complete chromosomal set of durum or soft wheat and one Th. elongatum genome. Translocations likely occurred.

The synthetic species T. duelongatum Pol. (2n = 6x = 42) with the genomic formula AABBFF has been isolated. This species is self-fertilizing and high stable cytologically (Poleva and Lyubimova 1995). The species is crosses well with T. durum, T. aestivum, and Triticum X Agropyrotriticum Cicin (2n = 8x = 56). The percent of hybrid seed set increases with an increase in ploidy level, 12.5 % (with T. durum), 39.0 % (with T. aestivum), and 58.4 % (with XAgropyrotriticum). F1 hybrids are fertile in the aforementioned combinations. High seed set (56 %) also has been noted in triticale (AABBRR)/T. duelongatum hybrids.

In the octoploid genotypes, lines have been isolated with valuable useful and practical features (high protein content, to 18 %; high spike yield, 2.3-2.5 g; and combined resistance to pathogens in the field). The lines are of interest for study as grain or hay crops and source material for wheat and triticale breeding.

The Triticum X duelongatum and Triticum X Agropyrotriticum are kept in the herbarium of Main Botanical Garden of the Russian Academy of Sciences.

Reference.

• Poleva LV andLyubimova VF. 1995. Remote hybridization of wheat and Elytrigia elongate (Host.) Nevski. Bull Main Bot Garden 171:48-60.

Selection of soft wheat lines with disomic substitutions of chromosomes of Ae. speltoides. [p. 104-105]

V.G. Kyzlasov, G.L. Yatchevskaya, and H.N. Lazareva.

Disomic substitution (2n = 42) lines of wheat were selected in a hybrid population of the cross T. aestivum/Ae. speltoides. Initially, flowers of a soft spring wheat were pollinated by Ae. speltoides. Before pollination, the pollen of Ae. speltoides was irradiated with gamma rays at 10 kR. Among the progeny obtained, matromorphic plants F1M1 with asymmetric karyotypes (2n = 49) were found. These plants had 42 chromosomes from the soft wheat parent and 14 chromosomes of Ae. speltoides in their somatic cells (Lapochkina et al. 1994). In subsequent hybrid generations, disomic substitution plants were found in progeny, along with 44-chromosome plants. In these plants, one of pairs of wheat homoeologous chromosomes was substituted with a pair of Ae. speltoides chromosomes. Plants with 44 and 42 chromosomes represent winter wheats.

Disomic substitution lines are low in fertility and have small grain (Table 1). Many substitution lines have a higher number of grains/spike compared to the standard cultivar Inna. The advantage of disomic substitution lines over standard cultivars concerns the increased percentage of wet protein/grain and higher resistance to leaf rust. Disomic substitution lines are characterized by stable expression of traits. Flower fertility in the substitution lines does not differ from the standard cultivars of soft wheat. Disomic substitution lines have a lower winter hardiness than cultivars. These lines are tall and susceptible to lodging. During the last 8 years, no leaf rust was observed on the leaves of the disomic substitution lines. When the disomic substitution lines are crossed with soft wheat, the F1 hybrids are resistant to the leaf rust pathogen; the resistance genes are dominant. F2 hybrids from crosses of the disomic substitution lines and soft wheat segregate similar to monohybrids, 641 resistant:253 susceptible plants, a ratio of 2.55:1. Leaf rust-resistance genes are inherited from the Ae. speltoides chromosomes. In hybrid populations of the second and subsequent generations, plants not resistant to leaf rust were observed, because of gametes heterozygous for resistance or susceptibility.

The interrelationship between the expression of quantitative characters showed that spike productivity positively correlates with number of grains/spike in disomic substitution lines (Table 2). The increase of number of grains/spike results in an increase in spike productivity. Conversely, wet protein content/grain negatively correlates with 1,000-kernel weight. A decrease in grain size results in an increase of wet protein content/grain. The other traits studied do not correlate with each other.

In disomic substitution line/soft wheat F1 hybrids, heterosis was found for yield, spike productivity, stem length, and 1,000-kernel weight (Kyzlasov et al. 2003a). A decrease in the number of grains/spike was observed. Some disomic substitution lines contain 18.2 % wet protein/grain (Kyzlasov et al. 2003b), 59.6 % higher compared to the standard cultivar Inna (11.4 %). We found that disomic addition lines have nearly twice the amount of wet protein content/grain when compared to the standard cultivars. These disomic substitution lines can be used as parental hybrid forms in selecting soft wheats to increase of wet protein content/grain and resistance to leaf rust pathogens.

References.

• Kyzlasov VG, Lapochkina IF, Yatchevskaya GL, and Lazareva HN. 2003a. Heterosis and depression in development of characteristics of productivity in hybrids F1 of disomic substitution (2n=42) wheat-Aegilops lines with soft wheats. Moscow Agric Acad Pp. 148-152 (In Russian).
• Kyzlasov VG, Lapochkina IF, Yatchevskaya GL, and Lazareva HN. 2003b. Development of economically valuable features in disomic supplemented and disomic substitution wheat-Aegilops lines. In: Internat Sci Practice Conf Priority trends in selection and seed breeding of agriculture plants in the XXI century. Rus Acad Agric Sci, Moscow. Pp. 405-407 (In Russian).
• Lapochkina IF and Volkova GA. 1994. Creation of collections of lines of spring soft wheat, substituted or supplemented with chromosomes of Ae. speltoides Tausch. J Genet 30:142-143 (In Russian).
  

 

AGRICULTURAL RESEARCH INSTITUTE FOR SOUTH-EAST REGIONS - ARISER

410020 Toulaykov str., 7, Saratov, Russian Federation.

Comparing pairs near-isogenic lines differing by alien Lr gene combinations. [p. 106-107]

S.N. Sibikeev, V.A. Krupnov, S.A. Voronina, and O.V. Krupnova.

A set of NILs from the Department of Genetics at ARISER with a combination alien translocations Lr9+Lr19, Lr19+Lr23, Lr19+Lr25, and Lr19+Lr26 into the genetic background of cultivars L503, Dobrynya, and line L2032 have been included in 2003 for the first time. For grain yield in 2003, NILs resistant to leaf rust are not different from cultivars and lines, except for pairs containing Lr19+Lr23 translocations in the genetic background of the cultivar Dobrynya and Lr9+Lr19 in the genetic background of line L2032 (Table 1).

Differences in grain yield between Dobrynya and its NILs with Lr9+Lr19 and Lr19+Lr23 translocation combinations were observed. The NILs had significantly lower parameters. However, between the same cultivar and NILs with Lr19+Lr25, no differences were observed. Nevertheless, the Lr9+Lr19 translocation in the NILs of L2032 and also the combination of translocations Lr19+Lr26 in the cultivars L503 and L2032 did not influence grain test weight. For lodging resistance, the NILs in the genetic background of the cultivar Dobrynya did not differ among themselves or from Dobrynya, however, the Lr26 translocation has increased resistance in the cultivar L503 and line L2032. At the same time, the Lr9 translocation has lowered lodging resistance 1.2 points in line L2032.

In 2003, frequent rains during harvest caused preharvest sprouting. We evaluated for a-amylase activity for falling number. The cultivars L503 and Dobrynya have the best parameters, 443 and 400 sec, respectively. Introducing the Lr26 translocation into the genetic background cultivar L503 significantly decreased the falling number. However, in the line L2032, this translocation (from cultivar Genaro 81) significantly increased this parameter. We have no basis to assume that the marked differences between the named lines is connected with the Lr26 translocation or other linked genes in various genetic backgrounds. Similar results were observed for the Lr9 translocation in the genetic background cultivar Dobrynya and line L2032.

Differences in SDS parameters were obtained only between sibs of L503 with presence and absence of translocation combination Lr19+Lr26. The isoline with Lr19+Lr26 had lower SDS parameter values, differences were not observed for the other combinations.

Reaction of cultivars and T. aestivum lines to two races loose smut in Saratov. [p. 106]

A.E. Druzhin, T.D. Golubeeva, T.V. Kalintseva, and A.Yu. Buyenkov (Department of Biotechnology, Plant Breeding and Genetics, Saratov State Agrarian University by name N.I. Vavilov, 1 Teatralnay Sq., Saratov 410060, Russian Federation).

Two races of loose smut, race 23 (determined on a set of Russian differentials = X18, determined on Canadian differentials) and race X (unidentified), were used to assess resistance in a set of Russian cultivars and lines of T. aestivum. From Table 2, resistance to race 23 is found in cultivars with resistance genes Ut1, Ut4 (suspected sources of resistance are Ostka Galicyjska, Iumillo, and Crimean), and Ut5 (source resistance not established). The cultivar Saratovskaya 57 and line L2040 inherited resistance from a local Ukrainian cultivar. Resistance in line CI 12633 probably is from T. timopheevii. The source of resistance is not established in line L2358 and the cultivar Marroqui 588. Saratovskaya 60 (source of resistance Ostka Galicyjska, Crimean, and Yaroslav-emmer) and Saratovskaya 70 (hypothetical source resistance not established ) are highly resistant (< 10 %).

Race X appeared to be more virulent to many cultivars. The highest resistance was only in cultivars with genes Ut1, Ut4, and Ut5 and also cultivar Saratovskaya 57 and lines CI 12633 and L2358.

Spike productivity of bread wheat-alien lines. [p. 107]

N.V. Stupina and Yu.V. Lobachev (Department of Biotechnology, Plant Breeding and Genetics, Saratov State Agrarian University by name N.I. Vavilov, 1 Teatralnay Sq., Saratov 410060, Russian Federation), and S.N. Sibikeev.

Were studied bread wheat-alien lines for parameters of spike productivity (spike length, number spikes/plant, spike weight, number of grains/spike, and grain weight/spike) for the standard bread wheat cultivars Saratovskaya 29, Saratovskaya 58, and L503 (Table 3). As a result of this analysis, we have selected two lines that surpass the productivity of the standard cultivars. The line L3266, with a 6D-chromosome substitution from 6Ag from Ag. intermedium, exceeded all standard cultivars for number of spikes/ear and grains/spike. Saratovskaya 29 and Saratovskaya 58 had the largest spikes and L3266 significantly exceeded cultivar Saratovskaya 58 and was equal to Saratovskaya 29 and L503 for spike weight and grain yield/spike. Line L3262, which has the Lr19 translocation and alien material from T. durum cultivar Saratovskaya zolotystaya for spike length and quantity/plant, exceeded Saratovskaya 29 and Saratovskaya 58 and was equal to L503. L3262 also exceeded Saratovskaya 58 for spike weight, quantity of grains/spike, and grain weight/spike. This line exceeded cultivars and was at a level equal to Saratovskaya 29 and L503. The lines L3269 and L3270 contain genetic material from Ag. elongatum and are not as good as the standard cultivars for in spike productivity except for spike length.

Black point in spring bread wheat in Saratov. [p. 108]

V.A. Krupnov, G.Yu. Antonov (Department of Biotechnology, Plant Breeding and Genetics, Saratov State Agrarian University by name N.I. Vavilov, 1 Teatralnay Sq., Saratov 410060, Russian Federation), O.V. Krupnova, and Y.E. Sibikeeva.

In 2003, kernel black point was observed at 20.6 to 26.0 %. Seed was lightly infected with fungus of Alternaria spp. The cause of kernel black point possibly was the physiological influence of vegetative conditions. We examined the effect of black point on the germination and quality grain in popular cultivars of spring bread wheat, Belynka (white kernel), L 503 (red kernel), and Dobrynya (red kernel). Belynka is susceptible to preharvest sprouting and L 503 and Dobrynya have some tolerance. Spike sampling for germination tests began when the plant peduncle had turned yellow with no green color to the glumes (first date) and was repeated twice every third day (second and third dates). Seeds were harvested, hand-threshed, dried, and stored in refrigerator at -20 C. Germination tests were at 20±1 C in the dark on filter paper in Petri plates containing 6 ml of water.

Percent of the germination was lower for black point-infested seeds than for the control (uninfected seeds) (Table 4). These observations suggest that in 2003 black point did not contribute to preharvest sprouting. The mean 1,000 black-point kernel weight and wet-gluten content in the kernel of all three cultivars was significantly higher than the control. Mean SDS volume of the cultivars Belynka and Dobrynya for black-point kernels was lower than the control, but this difference was not significant.

Resistance of spring bread wheat to loose smut and common bunt. [p. 108-109]

M.R. Abdryaev and V.A. Krupnov, and A.Yu. Buyenkov and Yu.V. Lobachev (Department of Biotechnology, Plant Breeding and Genetics, Saratov State Agrarian University by name N.I. Vavilov, 1 Teatralnay Sq., Saratov 410060, Russian Federation).

Recently in the Volga region, we have noticed an increase in loose smut and common bunt on spring bread wheat. We screened 19 cultivars and lines for resistance to loose smut and common bunt using artificial inoculation. The cultivars and breeding lines were from ARISER material. The loose smut inoculum was taken from cultivars L 505 and Saratovskaya 60. A suspension was prepared at 1.5 g spores/l water. Infection of loose smut used a medical syringe at flowering, adding to each a strict dose of inoculum. Spores of common bunt were from the susceptible cultivar Tulaikovskaya 5. For each inoculation, 1 mg spore/100 was used. Infection was directly before seeding. Disease estimates were made in field conditions.

Only two of the 19 cultivars and lines were resistant to loose smut and common bunt, L 4050-02 and L 2040. L 4050-02 has shown less than 3 % infection with common bunt and is immune to both the L 505 and Saratovskaya 60 pathotypes of loose smut. L 2040 is resistant to the pathotype collected from L 505; 11.5 % of the plants sporulating when infected with this pathotype. With the loose smut isolate from Saratovakaya 60, 8 % sporulation on plants was observed. For common bunt, the line L 2040 is moderately resistant (less than 22 % sporulation). The possible donor of resistance to these diseases in L 4050-02 is T. turgidum subsp. dicoccum and in L 2040 is T. turgidum subsp. durum.

The cultivars Lutescens 62, Yuogo-vostotchnaya 2, and line L 196 were moderately resistant to common bunt (0-10 % sporulation); line L 360-01 and cultivars L 503, L 1089, Saratovskaya 60, and Saratovskaya 29 had 11-30 % sporulaiton. Resistance to common bunt in these cultivars and lines originated from T. turgidum subsps. durum and dicoccum according their pedigrees. A group moderately resistant to loose smut included line L 894 and the cultivar Tulaikovskaya 5. The majority of the cultivars and the lines are either resistant to loose smut and susceptible to common bunt or vice versa.

FAR EASTERN RESEARCH INSTITUTE OF AGRICULTURE
Institute of Complex Analysis of Regional Problems, Karl Marx str., 105 A, kv. 167, Khabarovsk, 680009, Russian Federation.

Enzyme and mycosis exhaustion in seeds of Triticum aestivum in the far eastern Russian Federation. [p. 109-111]

Ivan Shindin, Vladimir Cherpak, and Sergei Phirstov.

The climatic conditions of the offshore and continental regions in the far-eastern Russian Federation are characterized by spring and early summer drought, summer monsoons due to the closeness of the Pacific Ocean, and high humidity. The annual precipitation in July and August makes up 65-75 % of the total annual precipitation.

For many years, research on enzyme and mycosis seed exhaustion (EMSE) has been done in western regions of the Russian Federation and the Ukraine. This research indicates that the causes of disease development were abiotic in nature, which were compounded by biotic factors including fungal diseases. Wheat cultivars show susceptibility to EMSE in high humidity and temperature conditions during the flowering and ripening stages (Alimov l988; Buryakova l974; Dunin et al. 1981; Kravchenko l98l; Shiltsova 1985).

In the far-eastern regions of the Russian Federation, scientists did not pay close attention to EMSE in spite of the spread of harmful kernel and spike diseases such as Helminthosporiosis and Fusarium wilt. The main pathogens of these diseases are Bipolaris sorokiniana (Saco.), Fusarium sambucinum Fuck., F. semiteotum Berk. et Rav., F. avenaceum (Fr.) Sacc., F. gibbosum App. et Wr., and Alternaria species. Yield losses, especially during years of epidemics, are considerable.

For a long time, the mycosis stage of the disease was studied separately from the enzymatic stage. The stage of enzyme affection of the grain was neither identified nor defined. In 200l-03, research on the spread and harmfulness of EMSE in released and perspective spring wheat oultivars from Khabarovsk selections was done at the Far Eastern Research Institute of Agriculture. This research identified biological kernel damage at milk, wax, and complete ripeness stages. Cracks in the caryopsis in the cultivar Khabarovchanka were observed. Cracks in the caryopsis and streaks and spots are typical symptoms of EMSE. The greatest number of cracks were in the pappus of kernals. The size of spots, streaks, and cracks varied from 0.5- l.2 mm (width) to 0.5-3 mm (length). Spots and streaks were on the top layer of caryopsis, some cracks were deep. Damage to the internal tissues of the grain were observed. Colonization and development of Fusarium and B. sorokiniana were noted.

In 2001, the incidence of EMSE low. During wax ripeness stage, disease development was not more than 2-3 % in some spring wheat cultivars. We noted that during our observations from 25-30 July, the first stages of the disease (enzyme), which is characterized by cracks in the caryopsis and exuding of kernal contents from the forces of osmotic pressure, were observed only in a few kernals. The typical EMSE symptoms, streaks, spots, and cracks, were not noted in the cultivar Lira during that period.

The loss of kernel contents caused by EMSE was determined in separate spikes according to the method of Dunin et al. (l981) in 2002-03. For this purpose, 40 typical spikes at milk stage were taken from different places in the plot. Spikes of the same cultivar but at different stages of ripeness (wax and complete) were selected as oontrols. The spikes were kept in waterproof bags and divided into two groups of four samples each; oontrol (dry), C1-C4, and El-E4 (experimental). In the laboratory, all kernels were immediately removed from each sample of the control group and oounted. The average humidity and l,000-kernel, dry substance weight were defined. For this purpose, the samples of group El-E4 were placed in water at a temperature of 3°C for l0 min, surplus moisture drained for 3 min, and the spikes placed horizontally in a cell at 30°C and 95 % humidity for 48 hr. After 48 hr, all kernels from the experimental samples were removed and counted. The average humidity and l,000-kernel, dry substance weight was determined for each sample. The loss of dry substances was an index of relative cultivar stability to kernel exhaustion was defined according to the formula:

(C - E) * 100

E % = -------------------

C

The results show that the loss of dry substances in all experimental T. aestivum cultivars increased between the stages from milk to wax to complete ripeness (Table 1). If the loss of dry substances at milk stage in Khabarovchanka were 2.8 % in comparison with the control, the loss in Zaryanka and Lyra 98 increased from 1.8 to 19.2 % and from 5.1 to 21.1 %, respecitvely. The same results were observed for the other cultivars (Table 1). We note that dry substance losses can be partially or completely compensated for by photosynthesis at the milk or wax stages, but this process is irreversible at complete ripeness.

In 2002, resistance to EMSE in the mature kernel after a late harvest was estimated. For this purpose, four 100-kernel samples were selected from freshly harvested grain during a period of heavy rain, prolonged dew, and fog. Both healthy, emerged, sprouted, EMSE affected, and thin kernels were marked in each sample Visually healthy caryopses accounted for 69-79 %, emerged 10-19 %, sprouted 1-7 %, visibly affected 2-8 %, and thin 2-4 % (Table 2).

The thin-kernel symptom is not specific for EMSE. Although the thin-kernel symptom was not separately taken into account but assessed with the oomplex of conditions during ripening, it is of great diagnostic importance (Temiverkova 1996).

1n 2003 we evaluated resistance to EMSE in the cultivar Khabarovchanka during a late harvest (Table 3). The harvest was made between 1-5 September. Visibly healthy kernels averaged 19.8 %, those effected by the first (enzyme) stage were 47.5 %, those affected by the second (mycosis) stage were 9.5 %. The total amount of kernels effected by EMSE was 74 %.

Bad weather in the summer of 2003 influenced seed quality. A late harvest led to EMSE development because a long monsoon fell during the milk and wax stages and after the crop was ripe.

The worst EMSE epidemics that can cause a 50 % yield loss happen from the combined action of both enzyme and mycosis infections. The mycosis stage causes the most harm, because semiparisitic and saprophytic fungi and bacteria, mostly species of Helminthosporium, Fusarium, Alternaria, Septoria, and Cladosporium develop more intensely during this period in the far-eastern region of the Russian Federation. Currently, one of the most important problems in T. aestivum selection is the search for sources resistant to EMSE (Shindin 2002).

References.

• Alimov KG. 1988. Basing of EMSE and infections control measures when using an intensive spring wheat cultivation technology in forest-steppe zone of western Siberia. PhD thesis abstract (In Russian). P. 19.
• Buryakova AI. l974. Wheat kernal 'Exhaustion' and winter wheat altenaria spot. In: PhD thesis abstract (In Russian). P. 20.
• Dunin MS, Temirbecova SK, Popova AV, and Tyuterev SL. 1981. Physiological and biochemical mechanisms of enzyme arid mycosis seed exhaustion (EMSE) in wheat and some other crops. Vestnik agronauky 4:70-78 (In Russian).
• Kravchenko ML. 1981. The ways of grain crops evaluation on kernal exhaustion resistance due to overmoistening. Vestnik agronauky. 24:78-95 (In Russian).
• Temirbekova SK. 1995. Diagnosis and evaluation of grain crops resistance to EMSE. Methdical Instruction, Moscow. 115 p. (In Russian).
• Shiltsova MA. 1985. Working out and improvement of evaluation methods of grain crops to EMSE and their application in practice. In: PhD thesis abstract, Lenningrad (In Russian). P. 19.
• Shindin IM. 2002. Theoretical and applied aspects of agricultural plants selection. In: Selection of works, Khabarovsk. Pp. 200-204 (In Russian)
  
  

IRKUTSK STATE AGRICULTURAL ACADEMY
Molodyozhnyi settlement, Irkutsk, 664038, Russian Federation.

 

The impact of environment-forming plants on crop capacity and quality of wheat grain in East Siberian Predbaikaliye. [p. 112-113]

Sh.K. Khusnidinov and T.G. Kudryavtseva.

The agroecosystems of Predbaikaliye (East Siberia, Russian Federation) are characterized by open, unstable, and low biological productivity. Turning to an environmentally friendly and biological approach to agriculture in creating highly productive agroecosystems makes extremely important the use of potential of so called supporting environment-forming plants; both traditionally cultivated and those presently introduced in Predbaikaliye.

Evaluating the productivity of experimental crops took into account the productivity of the following environment-forming plants: goats-rue (Galega orientalis L.), polygonum spread (Polygonum divaricatum L.), hill mustard (Bunias orientalis L.), sainfoin (Onobrychis arenaria (Kit. DC), alfalfa (Medicado sativa L.), yellow sweet clover (Melilotus officinalis Desr), and the wheat crops cultivated afterwards. Experimental links to crop rotation were based on the spring wheat cultivar Angara 86, characterized by precocity, environmental stability, and high productivity. Investigations of the agronomic efficiency of agroecosystems created were conducted in 1996-2000 on the light-gray forest soils that occur frequently in Predbaikaliye. Productivity of experimental crops was compared with productivity of crop rotation link, pure fallow-wheat, which presently is used widely in regional agriculture.

Our investigations have shown that new plants of limited occurrence and those traditionally cultivated in the region have a high productivity potential (Table 1). They are capable of performing several functions in crop rotation. Their use in agricultural production contributes to strengthening of forage reserve, enrichment of soil by fresh organic substance, and intense increase of wheat productivity. As compared to crop productivity achieved in a pure fallow-wheat (3.24 t/ha) system, crop rotation links with supporting plants reached crop productivity of 5.20 to 7.55 t/ha. Productivity excess in experimental links of crop rotation as compared to control variant amounted to 1.96-4.31 t/ha in 2 years. New plants and plants of limited occurrence as predecessors after 4 years of use (2 years for yellow sweet clover) produced positive effect on soil fertility, as well as wheat productivity both in the first year and later on in the second year of use. Observations have shown that use of environment-forming plants for wheat crops in the second year upon ploughing the bed contributed to the increase of its productivity by 1.61-1.93 t/ha.

We studied the impact of new plants and plants of limited occurrence as predecessors on wheat grain quality in Angara 86. Assessing baking quality included determining protein and gluten content, assessing technological quality by determining natural mass and 1,000-kernel weight, and sowing quality, germination capacity, and energy (Table 2).

Protein and gluten content are key parameters reflecting quality of wheat grain, flour, and baking. Technologists believe that natural mass is an important parameter as well. Natural mass is directly related to flour yield. Grain with a low natural mass is normally frail and demonstrates low flour yield. The 1,000-kernel weight characterizes grain filling. This qualitative parameter depends on the peculiarities of the cultivar and conditions of its cultivation including preceding plant.

Major indices of seeds quality are germination and germination energy. Initial protein content of 14.8 % in wheat grain sown after pure fallow increased up to 15.1-15.4 % in wheat grain sown after traditional plants, new plants and plants of limited occurrence (the increase amounted to 10.1-10.4 % of initial content). Gluten content in wheat grain increased from 11.3-13 %. Technological and sowing qualities of grain improved. Therefore, use of potential of traditional plants, as well as new ones and those of limited occurrence, their introduction in the system of regional crop rotation contributed to the increase of wheat productivity and grain quality in Eastern Siberia.

MOSCOW STATE UNIVERSITY
119992, Moscow, GSP-2, Leninskye Gory, Biology Faculty, Department of Mycology and Algology, Russian Federation.
www. lekomtseva@herba.msu.ru

 

Pathotypes of wheat stem rust pathogenic on different plant hosts from 1996-2000. [p. 114-116]

S.N. Lekomtseva, V.T. Volkova, L.G. Zaitzeva, and M.N. Chaika.

The mass epidemic of stem rust on wheat last year is rarely observed. The reasons for a low level of infection are resistance to the disease and the meteorological conditions during the growing season limiting development of a fungus on the host after development on the alternate host. Under favorable conditions, infections appear as separate loci on several plants. Lately, studying the composition of the populations of fungi is of decreased interest.

Annually, the urediniospores of stem rust are found in air currents throughout the Russian Federation. The aecial stage of P. graminis develops on different species of barberry (Elansky et al. 1998; Lekomtseva et al. 1999, 2000). Our work attempted to identify and characterize pathotypes of P. graminis f.sp. tritici on different plant-hosts in several areas of the Russian Federation, the Ukraine, and Georgia in 1996-2000.

Aecia from leaves of various barberry species were collected annually at the same sites; botanical gardens in the Moscow and Rostov (Rostov-on-Don) regions of the Russian Federation and Lvov, Ukraine. In some years, samples of wheat with stem rust were collected from plantings in the Russian Federation (Rostov and Primorski Krai regions), Ukraine (Kiev region), and Georgia (Kobuleti area). Besides isolates of stem rust from couch-grass (Elytrigia repens) and barley were analyzed. In rare cases, these isolated could cause a stem rust infection in wheat. Inoculation of wheat plants was done by the standard methods. To identify pathotypes (phenotypes of virulence or physiological races), 16 NILs of wheat received from the Cereal Diseases Laboratory, University of Minnesota, St. Paul, U.S., were used. Pathotypes were identified using the system of Roelfs and Martens.The development of the aecial stage of P. graminis f. sp. tritici on various species of barberry in 1996-2000 differed according to season. As a rule, aecia developed only on separate leaves. The fungus was not found on barberry in 1997 and 2000. In collections of different species of barberries in botanical gardens, both stem rust-susceptible and resistant species are cultivated. The most significant development of stem rust on barberry was observed in 1996 and 1998, and 1999 (Table 1).

Monitoring virulence phenotypes of P. graminis f. sp. tritici in 1996-2000 on all studied species of plant-hosts indicated that the most prevalent pathotype was MKCT with virulence to genes Sr5, Sr6, Sr7b, Sr8, Sr9e, Sr9g, Sr9d, Sr10, Sr17, and SrTmp (race 34 on the Stakman scale). On wheat from Georgia, the pathotype RKCT was identified, which has virulence on Sr5, Sr6, Sr7b, Sr8, Sr9b, Sr9e, Sr9g, Sr9d, Sr10, Sr17, and SrTmp (race 11).

In 1997 in the Moscow region, seven of 16 tester lines of wheat from the U.S. cultivated in a field for multiplication were infected with stem rust. The degree of damage reached 100 %. On wheat from the agricultural station of the Moscow University surrounding a site for multiplication of wheat lines, stem rust was absent. On these lines, pathotype MKCT also was dominant, and pathotype MKFT was identified on one of the tester lines. The presence of these infections can be explained by susceptible lines of the plant-host not of local origin.

Using the Pgt virulence system of Roelfs and Martens (1988), three pathotypes of P. graminis f. sp. tritici. were registered for the first time during 5 years on various plant-hosts in some areas of the Russian Federation, Ukraine, and Georgia. Pathotype MKCT simultaneously was found on barberry, wheat, and couch-grass. Two pathotypes of wheat stem rust were found within the European continent; MKCT in Italy and Turkey and RKCT (Sr5, Sr6, Sr7b, Sr8, Sr9b, Sr9e, Sr9g, Sr9d, Sr10, Sr17, and SrTmp) in Yugoslavia (Manninger 1994; Stojanovic et al. 1994; McCallum et al. 1994, 1999). We also found the RKCT pathotype in the samples of wheat from Georgia. At the same time, the stem rust-resistance genes Sr9b, Sr9e, Sr11, Sr21, Sr30, Sr36, and SrTmp are useful against the majority of stem rust pathotypes. Thus, they are of interest for selection of wheat lines resistant to stem rust (Table 2).

Unfavorable conditions for the development of stem rust can cause P. graminis f. sp. tritici infections on additional plant-hosts. These results can be important when epidemics of stem rust develop on wheat in favorable conditions.

Acknowledgement. This work is supported by the Russian Foundation of Basic Researches.

References.

• Elansky SN and Lekomtseva SN. 1998. Various fungal taxa spores frequency in the lowermost layer atmosphere in Middle Russia. Micologia i fitopatologia Pp. 37-43 (In Russian).
• Lekomtseva SN, Volkova VT, and Chaika MN. 1999. Populations of stem rust pathogen Puccinia graminis tritici on Pgt-lines of wheat. Vestnik Moskovskogo Universiteta Ser Biologia Pp. 48-50 (In Russian).
• Lekomtseva SN, Volkova VT, and Chaika MN. 2000. Ecial populations of Puccinia graminis on barberry plants in the region where sexual or asexual development of the fungus dominates. Micologia i fitopatologia Pp. 59-62 (In Russian).

Virulence of wheat stem rust, Puccinia graminis Pers. f. sp. tritici, in the Russian Federation and Ukraine in 2001-02. [p. 115]

S.N. Lekomtseva, V.T. Volkova, L.G. Zaitzeva, and M.N. Chaika.

Monitoring of virulence of the most dangerous wheat diseases is important for selection of resistance to the pathogen. In 2001 in some regions of the Russian Federation and Ukraine, a strong infection of wheat stem rust was observed. The analysis of virulence of P. graminis f. sp. tritici from some areas of the Northern Caucasus (the Rostov region), from central Russia (the Moscow region), and also from the area of the Chernobyl Atomic Power Station (the Kiev region), Ukraine were studied. In 2002, wheat stem rust development was low. However, we collected samples of the plants infected with stem rust on separate small sites within these regions. For the first time in 2002, the virulence of a wheat stem rust pathotype from western Siberia (the Tomsk region) was studied.

The definition of pathotypes of the stem rust fungus was made using Pgt-lines of wheat. In 2001, the pathotype TKNT, which is virulent to Sr5, Sr6, Sr7b, Sr8a, Sr9a, Sr9d, Sr9e, Sr9g, Sr10, Sr21, Sr30, Sr36, and SrTmp was observed in all areas (27 % of all studied isolates) and, in 2002, it was observed in central and western Siberia (6 %). The pathotype MKBT (Sr5, Sr6, Sr7b, Sr8a, Sr9a, Sr9d, Sr9g, Sr10, and SrTmp) was found in the Russian Federation in 2001 (9 %) and 2002 (20 %). MKBT was found in all areas of the Russian Federation (including western Siberia) and Ukraine. In 2001 in the Northern Caucasus and Ukraine, pathotypes TKNS (Sr5, Sr6, Sr7b, Sr8a, Sr9a, Sr9e, Sr9g, Sr10, Sr21, Sr30, and Sr36; 12 %), TKNP (Sr5, Sr6, Sr7b, Sr8a, Sr9a, Sr9g, Sr21, Sr30, Sr36, and SrTmp; 9 %) and TKPT (Sr5, Sr6, Sr7b, Sr8a, Sr9a, Sr9e, Sr9g, Sr21, Sr30, Sr36, and SrTmp; 7 %) were found frequently.

 

OMSK STATE PEDAGOGICAL UNIVERSITY
Chemico-Biological Faculty, nab. Tuchachevskogo, 14, Omsk, 644099, Russian Federation.

 

Effect of light quality on the development and some physiological parameters of the durum wheat plants and calli cultivated in vitro. [p. 116-118]

Natalia A. Kuzmina.

Light is one of the most important factors of a plant life, not only as a source of energy for photosynthesis, light also is involved in a variety of regulatory processes of plant growth and development. Light-dependent processes do not consume much energy but are very sensitive to the light spectrum due to specific properties of some plant photoreceptors absorbing at a narrow band of photosynthetically active radiation (PAR) (Voskresenskaya 1979; Kefeli 1987; von Armin and Deng 1996). Some different types of the receptors have been described, including phytochromes (red light), cryptochromes, and phototropin (blue light). Furthermore, plants contain innumerable flavoproteins and carotenoproteins, significantly complicating the quest for the one or few that might function as blue-light receptors (Volotovsky 1987; Ahmad 1999; Lin 2000; Briggs 1999). Heliochrome, a kind of green light receptor, might be associated with phytochrome and cryptochrome (Tanada 1984). Some initial stages of plant growth (seed germination, stem and leave morphogenesis, development of the chloroplasts, and authotorophy) are tightly associated with functions of the phytochrome and a blue light receptors.

The photoregulatory reactions of intact plant tissues might be quite different from those of callus tissues, depending on the ability of calli to consume an organic carbon from the nutrition medium. Some studies on the effects of light quality on plant growth and some metabolic processes were contradictive (Tikhomirov et al. 1987; Shalaeva et al. 1991; Karnachuk and Golovatskaya 1998). Very few papers address the effects on callus tissue (Karnachuk and Gvozdeva 1998; Butenko 1964). Because callus production is essential for selection, particular attention should be paid to further investigating the effects caused by a different light qualities.

In the present study, we examined the effects of the light spectrum on growth and some photosynthetic parameters of intact shoots and callus tissues of durum wheat.

Material and methods. Seed of the durum wheat cultivar Ametist were incubated in damp, 96-well polystyrene plates subjected to continuous illumination by the blue (BL), green (GL), red (RL), or white (WL) light from fluorescent tubes (Osram, Germany) or in the darkness (D) at 25-28 C. Leaf length and the dry weight of the leaves, roots, and grains were determined from day 3 to 11. Samples were fixed in a drying chamber at 105 C for 15 min and at 60 C for 2 h. Chlorophyll concentration in the leaf tissue was determined on days 3, 5, and 7. Chlorophyll extraction used cold 85 % ethanol (Shlyk 1971). The square of the leaf plate was determined on day 10 and the specific space density value (SSD) was calculated according to the equation: m/S (mg/cm2) (Tooming 1977).

To induce callus formation, the upper parts of mature embryos were incubated on Murashige and Skoog (1962) medium supplemented with 2.0 mg/ml of 2.4-D. After 6 weeks, the calli were transferred to another tube with the same medium without hormone supplements to induce organogenesis. Calli were incubated in the light conditions described above for the intact shoots. Linear dimension and fresh and dry weight of the calli were measured after 6 weeks of incubation on the hormone-free medium (the end of observation).

Results and Discussion. Our study detected ambiguous effects caused by the different light spectrum in 1-week-old durum wheat seedlings (Table 1). The maximum length of the first leaf was detected under RL; the minimum in the D group. We did not detect a depression in development caused by BL as has been reported for A. sativa, Bergenia crassifolia L. Fritsch., Serratula coronata L., Lichnis chalcedonica L., Rhaponticum carthamoides Willd.-Iljin (Karnachuk and Golovatskaya 1998), Zea mays L., Cucumus sativus L., and Helianthus annuus L. (Tikhomirov et al. 1987). On the contrary, BL stimulated shoot development compared with WL. The weight of the shoots in plants illuminated with BL was significantly larger than that of those grown under WL or in darkness, whereas significant distinctions were not detected among the RL, BL, and GL groups.

At the same time, the illumination variations did not alter root development. Data from the literature concerning biomass accumulation were quite different and contradictive. Tichomirov et al. (1987) showed that the biomass of cucumber and garden radish plants was maximum under BL, whereas the biomass of spring wheat was greatest under RL. Thus, the effect of different light spectra on plant biomass accumulation is still underinvestigated and, obviously, depends on many factors including plant species, exact light wavelength parameters and, probably, other conditions of the cultivation collaborating with light quality.

The SSD value, which represents the accumulation of dry matter per square unit, was proposed by some authors as a coefficient joining plant development with the photosynthesis processes, i.e., the more SSD detected, the greater the effect of the photosynthesis processes (Tooming 1977; Rasulov and Asrarov 1982). The SSD determined on day 10 was greatest in leaves grown under GL and, consequently, decreased in the following order: GL > WL > RL > BL (Fig. 1). The literature on this subject is limited and ambiguous. An increase in SSD under RL compared with BL was detected in the garden radish (Drozdova et al. 1987). A decrease in SSD was detected under GL in the R. carthamoides. In the B. crassifolia and L. chalcedonica, the SSD was greater under BL compared with RL. Finally, no dufference between BL and RL was found in R. carthamoides (Karnachuk and Golovatskaya 1998).

The maximum chlorophyll concentration was detected in leaves grown under WL, followed by RL (a twofold decrease). The lowest concentration was detected under BL and GL (Table 2). The fastest chlorophyll accumulation occurred between day 3 and 5. Initially suppressed, chlorophyll accumulation increased dramatically under RL, GL, and BL compared with WL. In 1-week-old shoots grown under BL and GL, no difference in chlorophyll concentration was observed (44 % of WT).

White and red light definitely stimulated callus development (Table 3). The lowest values of both fresh and dry weight were recorded for calli grown under BL. Thus, this part of the spectrum did not facilitate development. Red light promoted formation of mostly moist calli. Monochromatic light compared with darkness in inhibited development of calli grown on 2.4-D medium. After the calli were transferred to hormone-free medium, the effect vanished. Linear measures of the calli grown in the different light conditions were not significantly different at the end of observation. Similar light effects were described calli of spring wheat (Karnachuk and Gvozdeva 1998).

The current study demonstrated various effects caused by the light conditions and particularly by the light spectrum in the intact durum wheat shoots and callus tissues cultivated in vitro. Red and blue light, being favorable for shoot growth, inhibited development of calli. Red light also was important for chlorophyll, but it was insufficient for biosynthetic processes because they were improved almost twofold under WL. At the same time, photosynthetic processes were quite effective under GL because of improved leaf morphology, which subsequently resulted in length and weight equalization of the shoots grown under the monochromatic light.

References.

• Ahmad M. 1999. Seeing the world in red and blue: insight into plant vision and photoreceptors. Curr Opinion Plant Biol 2:230-235.
• Briggs WR. 1999. Blue-light photoreceptors in higher plants. Ann Rev Cell Dev Biol 15:33-62.
• Butenko RG. 1964. A culture of isolated tissues and physiology of plant morphogenesis. Nauka, 272 pp. (In Russian).
• Drozdova IS, Bondar VV, and Voskresenskaya NP. 1987. Coaction of light-controlled reactions induced by the red and blue light on photosynthesis and morphogenesis in radish plants. Plant Physiol 34:786-794 (in Russian).
• Karnachuk RA and Gvozdeva ES. 1998. The effects of light on hormonal balance and morphogenesis in wheat embryo-derived cultured tissues. Rus J Plant Physiol 45:289-295 (In Russian).
• Karnachuk RA and Golovatskaya IF. 1998. Effect of light spectral composition on the hormonal balance, growth, and photosynthesis in plant seedlings. Rus J Plant Physiol 45:925-934.
• Kefeli VI. 1987. Plant growth and photomorphogenesis. Plant Physiol 34:685-697 (In Russian).
• Lin C. 2000. Plant blue-light receptors. Trends Plant Sci 5:337-342.
• Murashige T and Skoog F. 1962. A revised medium for rapid growth and bioassays with tobacco tissue cultures. Physiol Plant 15:473-497.
• Rasulov BKh and Asrarov KA. 1982. Dependence of the intensity of photosynthesis of various cotton species on the specific space density of the leaf. Physiol Photosynthesis Nauka, pp. 270-283 (In Russian).
• Shalaeva EE, Lisovsky GM, and Tikhomirov AA. 1991. The light spectrum and some mesostructure properties of different plants. Plant Physiol 38:31-38 (In Russian).
• Shlyk AA. 1971. The method of chlorophyll and caratinoid extraction from the green leaf extracts // Biochemical metods in plant physiology. Nauka, pp. 154-170 (in Russian).
• Tanada T. 1984. Interaction of green or red light with blue light on the dark closure Albizzia pinnules. Physiol Plant 61:35-37.
• Tikhomirov AA, Zolotukhin IG, Lisovsky GM, and Sid'ko FYa. 1987. Specific responses in various plant species to spectral composition of on photosynthetically active radiation under artificial illumination. Plant Physiol 34:774-785 (In Russian).
• Tooming KhG. 1977. Sun radiation and the yield. Agropromizdat, 200 pp. (In Russian).
• Volotovsky ID. 1987. Phytochrome: structure and phisicochemical properties. Plant Physiol 34:644-655 (In Russian).
• von Armin A and Deng XW. 1996. Light control of seedling development. Ann Rev Plant Physiol Plant Mol Biol 47:215-243.
• Voskresenskaya NP. 1979. Photoregulatory aspects of the plant metabolism. Nauka, 48 p. (In Russian).

PRYANISHNIKOV ALL RUSSIAN RESEARCH INSTITUTE OF AGRICULTURE AND SOIL SCIENCE

Pryanishnikova, 31. Moscow 127550, Russian Federation.

The effects on root system acidification and aluminum tolerance from a pretreatment of wheat seeds prior to sowing with succinic acid. [p. 119-121]

N.M. Safronova, N.V. Poukhalskaya, N.I. Lavrushkina, and A.A. Sobachkin.

Succinic acid increases the resistance of plants to aluminum toxicity. We investigated the influence of succinic acid on the acidification of the root system in wheat seedlings of different cultivars (exchange H+/K+). Our research studied the mechanism of succinic acid action. Possible components of the effect of succinic acid, including hormonal regulation, chelation of Al^3+^ to decrease in aluminum toxicity, and the influence on K streams in roots, were estimated. A high specificity of roots and leaves on succinic acid is established.

Introduction. Modern ideas about aluminum tolerance in plants assume the simultaneous action of one or more mechanisms. One effective mechanism for root stability in plants is the capability of organic acids to form chelated aluminum ions (Delhaize et al. 1993; Ma et al. 1997). The potential role of organic anion exudates in conferring resistance to Al has been evaluated. Aluminum ions impede the potassium ions in a root and effect whole-root metabolism (Poukhalskaya and Gurin 2003).

Pellet et al. (1995) found 5-9 times the output malonate becomes more active in a solution containing aluminum ions. Other organic acids, except aconite acid, did not change. However, malonate, the lowest homolog of succinic acid, is the antagonist of succinic acid in some reactions (Malygin 1995). Gassmann and Schroeder (1999) suggest that potassium and aluminum ions compete to carry ions through the plasma membrane. We investigated the influence of succinic acid on potassium metabolism, absorption, and ion exchange (H+/K+), assuming that potassium is transported into cells by means of a proton pump. The efficiency of these parameters was estimated by a decrease in aluminum toxicity in the roots of seedlings of three spring wheat genotypes grown in solution.

Materials and methods. We estimated the acidification activity of the root system (AARS) after treatment seeds with succinic acid (internal influence of the succinic acid on AARS) and the AARS by immersing roots in a solution of succinic acid of increasing concentration (external influence of succinic acid on AARS) and determined the role of internal succinic acid on the change in aluminum toxicity.

Estimating AARS after treatment of seed with succinic acid (internal influence of the succinic acid on AARS). Seeds of spring wheats were treated with a succinic acid solution (0.05 %) for 24 h. The seedlings were grown in 30 ml of CaSO4 x 10^-4^ M (solution 1) one plant/pot. One hundred plants/genotype were grown. Two days-after-germination (20 C day/18 C night ± 2 C), the seedlings were transferred to KCl x 10^-3^ M + CaSO4 x 10^-4^ M (solution 2). The change in pH in solution 2 is an integral parameter of solution acidification, because potassium and hydrogen ions are transferred (exchange H+/K+) through the root membrane. The pH was measured individually for each plant; root length and vegetative measurements also were made. The change in pH between solution 2 from solution 1 was calculated for each of the 100 plants. The specific acidification activity (SAARS) of the root system was calculated by dividing the AARS by the total length of root system.

Estimating AARS by immersing roots in a solution of the succinic acid of increasing concentration (external influence of the succinic acid on AARS). The same techniques as above were used in the absence of succinic acid. Succinic acid was added in a solution containing KCl x 10^-3^ M + CaSO4 x 10^-4^ M at concentrations of 0.05 % and 0.1 %, respectively (solution 3). Seedlings were transferred to solution 1 for 24 hr after treatment in solution 2 and then put in solution 3. Differences in the pH of these solutions were characterized as influence of succinic acid.

The role of internal succinic acid in aluminum toxicity. Seeds of the spring wheat cultivars Priokskaya, Lada, and Ester were soaked for 30 min in H2O2, washed in H2O for 40 min, and then soaked in a 0.05 % solution of succinic acid for 24 h. After that treatment, the seeds were put in a water solution in plastic pots (300 ml, 10 plants/pot) in a climate-controlled chamber maintained at 20 C day/18 C night ± 20 C. Three nutrition regimes were used: (I) H2O + CaSO4 x 10^-4^ M (control), (II) KCl x 10^-3^ M + CaSO4 x 10^-4^ M, (III) KCl x 10^-3^ M + CaSO4 x 10^-4^ M with Al^3+^ (AlCl3 at pH = 5.6) at a concentrations of 3 mg/l. The roots of the plants were in solutions for 18 days. Solutions were replaced every 2 days. After 18 days, the plants were weighed and growth parameters determined.

Results. Succinic acid has an effect on the root system (Table 1). Seedlings with similar root lengths and treated with succinic acid had a 1.35 times shift in solution pH (Fig. 1). The pH shift was caused the greater intensity of K+ pumps, which implies that the accumulation of succinic acid in seeds is able to influence the absorption activity (SAARS). Treatment of seeds with succinic acid treatment did not influence root length after 7 days of growth. The internal succinic acid concentration does not produce an observable change of the population into two groups.

The external succinic acid concentration is always greater than the internal concentration. The external concentration of succinic acid always caused population biotypes to disappear. In our experiments, the external concentration of succinic acid (0.1 %, 0.05 %, and 0.01 %) causes stress in the plants (Table 2). The negative influence of H+ ions (acidity of a solution) on root systems is known. The root system of the cultivar Priokskaya in the presence of H+ ions caused a decrease in root length.

The amplification of the negative influence of acidity on the root system is accompanied first by the absence of an influence on vegetative parts, then active growth, and finally by a decrease in growth of the vegetative parts.

In experiments that studied the influence of the internal action of succinic acid (seed treatment) after the addition of such factors as the level of a potash nutrition and aluminum toxicity.

In the previous experiments, we showed that the root system of wheat cultivar Priokskaya reacts to succinic acid in a solution with a presowing treatment. In these experiments, isolating the action of succinic acid anions is not possible, because it is impossible to separate that action from the negative action of protons. In experiments with a longer growth period (18 days), we studied the action internal succinic acid on growth of the root system and development of plants in three cultivars of spring wheat (Priokskaya, Ester, and Lada).

We chose three genotypes in which the root system reacts differently to the addition of succinic acid at seed treatment. The negative influence of succinic acid leads to a decrease in root length in Lada and Ester. We observed a positive effect only for roots of Priokskaya. Thus, the influence of succinic acid on root growth of root of the three genotypes is not revealed. We did find that the root system of the Priokskaya genotype reacts to succinic acid (Fig. 2). The other two genotypes did not show an increase in root length. However, changes in leaf length were unequal for the genotypes (Table 3). Apparently, genotypes have a distinct metabolic reaction to the action of succinic acid. For example, comparing the weight of the root system with that of the leaf tissue of the cultivar Priokskaya, we observed an increase of 10 % with the addition of succinic acid. In the cultivar Lada, the increase was 27.1 %. The cultivar Ester has was lower for both the weight of roots leaves, resulting in a decrease of 19 %.

Similar changes are found for the influence of succinic acid on Al tolerance. Ions of aluminium (3 g AlCl3/l) lead to the inhibition of root growth after immersing roots in a solution. Al toxicity decreased the growth of roots in Priokskaya by 73 %. A seed pretreatment with succinic acid caused a decrease of 69 %. For the cultivar Ester, Al toxicity in the control (without succinic acid) decreased the root length by 7 % within 12 days after germination. We did not detect a decrease in the root length when the seeds were pretreated with succinic acid. For the cultivar Lada, growth in the control plants decreased 47.8 % but no decrease was observed with a succinic acid pretreatment. The absence of decrease in growth in cultivars Ester and Lada was combined with shorter root length in plants from seed pretreated with succinic acid. The reaction to succinic acid in these genotypes was expressed in a decrease in root length. Subsequent growth in a solution containing Al ions did not have an influence. A reduction in root length was combined with an increase in root diameter, therefore, the weight of the root system was an integral parameter of the reaction of root system to Al toxicity and the factors that influence them (Table 4).

Potassium exchange may be a protector mechanism that determines Al tolerance by means of potash nutrition optimization and creation of competing K+/Al+3 on the surface of the root system or may be a combination of mechanisms. Tolerance to aluminum in the cultivar Lada is not influenced positively by a seed pretreatment with succinic acid. Each factor separately increased stability to Al+3 in Priokskaya, but for Ester only an interaction of factors had an effect on increase of root weight in a stressed environment. Very different mechanisms for protection against Al ions are found in the three different genotypes. Research allows us to observe a variety of protection to Al ions in different genotypes. Studying a genotypes reaction to Al toxicity should, therefore, be multifactorial.

References.

• Delhaize E, Ryan P, and Rendall P. 1993. Al-tolerance in wheat. Aluiminum stimulated excretion. Plant Physiol. 103:695-702.
• Gassmann W and Schroeder JI. 1994. Inward-rectifying K+ channels in root hairs of wheat (a mechanism for aluminum-sensitive low-affinity K+ uptake and membrane potential control). Plant Physiol 105:1399-1408.
• Hue NV, Graddock GR, and Adams F. 1986. Effect of organic acid on aluminum toxicity in subsoils. Soil Sci Soc AMI 50:28-34.
• Ma IF, Zheng SY, and Matsumoto H. 1997. Specific secretion of citric acid induced by Al-stress in Crassia tora L. Plant Cell Physiol 38(9):1019-1025.
  Malygin G. 1999. Metabolism of carbonic acid (the periodic scheme). International education program. 39 pp.
• Pellet DM, Grunes DL, and Kochian LV. 1995. Organic acid exudation as an aluminum-tolerance mechanism in maize (Zea mays L). Planta 196:788-795.
• Poukhalskaya NV and Gurin AI. 2003. Aluminum tolerance in spring wheat plants at different levels of potassium and low temperature. Ann Wheat Newslet 49:106-107.

The effect of nitrogen nutrition on the adaptation of spring wheat under water stress. [p. 122]

Ludmila V. Osipova.

In experiments with spring wheat, we studied the effects of nitrogen nutrition on the level of resistance to drought. Experiments were under controlled conditions in a phytotron. Nitrogen levels varied from insufficient to high.

Water stress was tested by discontinuing water during spike formation. Drought conditions were defined by this duration. Water stress of any duration aggravate the lack of soil nitrogen. Plant height, spike length, number of spikelets, and grain yield were reduced. Effective adaptive reactions did not develop at low levels of nitrogen, thus, the use of water was reduced. Significant depression of efficiency was marked.

High levels of nitrogen provided for high productivity, even when plants received a short-term stress. High initial nitrogen levels prior to drought influenced the growth process. A high level of nitrogen nutrition created a basis for developments of adaptable reactions and active growth during reparation period. If growth is inhibited during the period of drought, outflow of assimilates and a decrease in CO2 absorption were observed. The intensity of photosynthesis and assimilation at the surface of leaves was reduced, but respiration level was high. Depressing physiological processes during water stress has been connected to growth activation and photosynthesis after resumption of watering.

Although the number of grains/spike was reduced, the 1,000-kernel weight increased. The high level of nitrogen nutrition appeared inefficient at strong water stress. Genotype determined the decrease in growth and water-holding capability and irreversible damage to leaf membranes. Thus, nitrogen nutrition conditions determine productivity and viability of wheat of different genotypes.

SARATOV STATE AGRARIAN UNIVERSITY NAMED AFTER N.I. VAVILOV
1 Teatralnaya Sg., Saratov, Russian Federation.

INSTITUTE OF BIOCHEMISTRY AND PHYSIOLOGY OF PLANTS AND MICROORGANISMS, RUSSIAN ACADEMY OF SCIENCES
13 Entusiastov Ave., Saratov, Russian Federation.

A novel molecular marker for morphogenesis in an in vitro culture of wheat. [pp. 122-123]

N.V. Evseeva, I.Yu. Fadeeva, and S.Yu. Shchyogolev (Saratov State Agrarian University), and O.V. Tkachenko and Yu.V. Lobachev (Russian Academy of Sciences).

The embryogenic potential of callus tissues is known to be dependent on many factors, including the functioning of embryonal antigens or morphogenetic markers, proteins associated with the embryogenic processes in an in vitro plant culture. In particular, we found that the wheat-callus-cell content of the prolific antigen of initial cells (PAI), characteristic of cereal-crop meristematic cells (Sumaroka et al. 2000), depends on the intensity of the morphogenetic processes occurring in these cells (Evseeva et al. 2002).

Using immunochemical and morphometric analyses, we studied the processes of callus formation and secondary differentiation with a genetic model including immature embryos of sister NILs (differing in the Rht-B1c alleles) and of the original cultivar (Saratovskaya 29) of soft spring wheat. The PAI content of immature embryos of the wheat genotypes under study was found to be the same, but it decreased in the process of formation of undifferentiated callus mass. However, the amount of PAI increased on the 21st day of callus formation (when meristematic centers were beginning to emerge in the callus tissue). Only on day 30 of callus formation were significant differences observed in the PAI content of the genotypes under study. The PAI content of the dwarf line (Rht-B1c gene) was higher than that of the tall line (Rht-B1a gene).

Experimental estimates of the PAI content are in agreement with results of the morphometric analysis and with previous results (Djatchouk et al. 2000), attesting that PAI is associated with differentiated cell divisions in the plants. Possibly, cells marked with this antigen in the callus-tissue meristematic center perform a function similar to that of the initial cells in the whole-plant meristems. Thus, further studies of the molecular mechanisms of PAI expression in an in vitro culture may facilitate elucidating the regulatory mechanisms of cell division and of subsequent differentiation in the whole-plant apical meristems.

References.

• Djatchouk TI, Tkachenko OV, and Lobachev YuV. 2000. In vitro influence of Rht genes on bread wheat and somatic embryogenesis of durum wheat. Ann Wheat Newslet 46:115.
• Evseeva NV, Tkachenko OV, Lobachev YuV, Mitrofanov AYu, Djatchouk TI, and Shcheogolev SYu. 2002. Studies on the embryogenic processes in vitro culture of wheat somatic tissues by using a proliferative antigen of initial cells. Wheat Inf Serv 94:1-4.
• Sumaroka MV, Dykman LA, Bogatyrev VA, Evseeva NV, Zitseva IS, Shcheogolev SYu, and Volodarsky AD. 2000. Use of the dot-blot immunogold assay to identify a proliferative antigen of the initial cells of a wheat stem meristem. J Immunoassay 21:401-410.
  
  

Contributions from the Russian Federation continue with the Siberian Institute of Plant Physiology and Biochemistry.