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Professor Tadeusz Wolski passed away on March 11, 2005 in age of 81. He is a great person in the history of plant breeding in Poland. In the text below we recall Professor Tadeusz Wolski’s work and achievements as our homage to him.

Potato Late Blight is one of the most devastating diseases worldwide. The yearly losses reach up to 10-15 % of the global crop, which is comparable to the total potato production in the EU countries. There are several national and international programs and initiatives to stimulate progress in breeding potato cultivars resistant to Late Blight. Here, the Global Initiative on Late Blight (GILB), joined by researchers from all continents, several finished and ongoing EU programs directed to the progress in Late Blight research as well as the Cornell-Eastern Europe-Mexico (CEEM)International Collaborative Project in Potato Late Blight Control need to be mentioned...

Several aspects of the ecology of oospores of Phytophthora infestans were studied in the Netherlands using both observational and experimental methods. Following the introduction of a genetically variable late blight population in Europe during the 1970s, P. infestans epidemics have become more severe, leading to an increase in fungicide use in many potato production areas in Northwestern Europe. In the Netherlands, oospores are readily produced in unsprayed crops and volunteer potatoes and their incidence varied from 78% to 15% of sampled leaflets with two or more lesions, for the northeastern and southwestern region in 2000, respectively. A fungicide application following infection of plants with an A1 and A2 mating type strain significantly reduced the number of oospores produced as well as oospore viability. Several alternative hosts facilitating oospore formation have been identified in the Netherlands: S. nigrum, S. dulcamara and S. sisymbriifolium. The impact of oospores on late blight epidemics is discussed.

Phytophthora infestans behaves in natural and agricultural ecosystems as a biotrophic pathogen, although it can be cultured on artificial media. Pathogenicity and host adaptation are therefore essential traits to understand its biology and to come up with durable, efficient management of late blight. The present review focuses on adaptation to host species and host cultivars, and to both qualitative and quantitative types of resistance. It also discusses some of the patterns and population mechanisms involved in this adaptation, such as selection, genetic drift and migration. This highlights the need for an in-depth analysis of each local situation to accurately describe and understand the mechanisms responsible for observed population displacements.

The procedure of evaluation is based on mathematical simulation model of the late blight (LB) development in combination with laboratory testing of detached leaflets artificially inoculated with Phytophthora infestans. An incubation period, amount and sizes of lesions and sporulation capacity are estimated. Each couple “tested Phytophthora isolate and tested potato cultivar” is compared with a standard couple “Phytophthora isolate N161 and standard cultivar”. A simulator on the base of these data calculates area under the curve for LB development and yield loss due to LB for a situation when a yield loss of a standard cultivar infected with a standard isolate is equal 35%. Comparison of a new rapid laboratory method and field methods showed satisfactory correlation. Resistance to late blight was evaluated for 47 potato cultivars with the new method. It was also shown that some variations in foliar aggressiveness existed among P. infestans populations from different regions. Supported by ISTC grant #1640.

Potato breeders and phytopathologists have been conducting the studies on Phytophthorainfestans (Mont.) de Bary at the Priekuli Plant Breeding Station since 1962. The varietal resistanceis very important in potato breeding programme. The trials in collaboration with the Institute ofPhytopathology of Soviet Union (Russia) were done in 1974-1990. The investigations were focusedon races of P. infestans. The changes of races were assessed using a “trap” method, according to theinvestigation programme, like in each of the republics of the Soviet Union.At the beginning of investigations (1960s and 1970s) races 1, 4 and 1.4 of P. infestans were thepredominant ones in Latvia, but in the 1980s complex races 4.10.11, 1.4.7.8.10.11, 1.3.4.7.8.10.11and 1.2.3.4.7.8.10.11 were more widely distributed.Different foreign varieties, mostly from the Netherlands, were introduced in Latvia in the 1970s.This resulted in a very rapid differentiation of late blight races. The enhanced aggressiveness of P.infestans isolates was due to an increasing number of races in population. The earlier appearance ofinfection in potato fields was recorded. The presence of a mating type A2 was stated in Latviansamples in 1987. Because all tested races had been recognized in a population, and the conception ofresistance breeding had been modified, the trials were stopped in 1990. The resistance based onspecific resistance genes was the main direction in the 1960s and 1970s. From the 1980s, impor-tance of the field resistance has greatly increased and this type of resistance is the most significantin the current breeding programme. The trials in organic field proved the acceptable level of fieldresistance to P. infestans of three medium late varieties: Sigunda (previous name Undine), Beteand Zile. These varieties have been bred at the Priekuli Plant Breeding Station and included intothe Latvian Plant Varieties Catalogue.

The effective management of protection against Phytophthora infestans must be established on the perfect knowledge of the pathogen. From a practical point of view this means identification of races and mating types as well as the pathotypes resistant to systemic compounds of fungicides. The main goal of our project was to characterize populations of late blight, especially in the most important area of seed potato production. Recognition of races and mating types and evaluation of resistance to metalaxyl of the isolates in potato-growing area were performed in laboratory tests. Isolates of late blight for laboratory tests were collected in commercial and research potato crops in the regions of Poprad and Kežmarok. The first occurrence of metalaxyl-resistant strains was noticed in 1999, and the greatest incidence was recorded in 2000. In the following years a significant decrease was observed. This was due, among others, to omitting fenylamide fungicides in crop protection in our region. The occurrence of isolates virulent to potato with R2, R5, R9 and R11 genes was noted neither in 1996 nor in 1997, and tested isolates had maximum six virulence factors. Since 1999, the occurrence of isolates with seven, eight or even ten virulence factors has been recorded. Presence of A2 mating type was not confirmed in our area until 2002. In 2003, more A2 than A1 isolates were found. It is likely that problems concerning the ability of oospores to survive in soil as well as sexual reproduction of the pathogen may appear also in our potato-growing area.

All definitions for integrated control agree that maximum emphasis should be put on prevention by using resistant cultivars and cultural measures. Moreover, the use of plant protection products should be limited to the essential minimum using Decision Support Systems (DSSs) that integrate and organise all relevant information. Computer-based DSSs that require weather information and regular late blight scouting inputs have been developed and validated in a number of European countries. In the frame of the EU concerted action “European network for development of an integrated control strategy of potato late blight (EU.NET.ICP)” several DSSs were validated in 1999-2001. The overall conclusion was that in most cases the use of DSSs combined a good disease control with a reduction of fungicide input. The DSSs can be used as a PC-version but more and more, parts of information are delivered to users by phone, fax, e-mail, SMS and websites on the Internet. An important task for the near future is to update the DSSs with information on the epidemiology of the new aggressive population of Phytophthora infestans. Issues such as (1) the influence of temperature and relative humidity on the infection process, (2) the role of primary inoculum sources (seed, oospores, volunteers, dumps), (3) the role of secondary inoculum sources (distance, severity), (4) control of early blight and (5) resistance ratings for foliar and tuber blight have to be addressed in order to be able to formulate a robust control strategy that effectively controls late (and early) blight with a minimum input of fungicides.

Changes in population of Phytophthora infestans can greatly influence the time of potato late blight appearance in potato crops. The late blight monitoring system makes it possible to evaluate reliability of the forecast provided by decision support systems that are applied in potato protection and in consequences defends in practice potato crops from early appearing infections. The first steps in creating Polish internet monitoring system in potato protection against late blight were based on observations carried out by advisers from the Plant Protection Inspectorate in Lublin voivodeship in the years 2001-2002. The conducted evaluations were part of the Polish-Danish research project “Development of an Internet based DDS for Cereal Diseases and Potato Late Blight in Poland, 2001-2002”. In 2003, the observations were also conducted in four other voivodeships. The collected results indicate that it is feasible to recognize primary early infections manifested as singular necroses on potato plants. The earliest infections were most frequently recorded on susceptible potato cultivars. In two cases in 2003, early attacks were recorded at plant growth stage of 30-31 (in 0-99 BBCH scale for potato). In most cases the first infection symptoms appeared at the growth stage exceeding 37. This indicates that very early infections caused by oospores from soil were not common in the inspected areas.

The resistance to late blight (LB) is considered as a factor of major importance among resistances to potato pathogens. For four last decades more work has been done on potato resistant to Phytophthora infestans than on breeding for resistance to any other potato disease. Many sources of resistance have been known to breeders for many decades, but the results of their utilization are still disappointing. The difficulties in breeding for LB resistance were assessed by 39 participants of the survey organized for the Global Initiative on Late Blight (Zimnoch-Guzowska and Flis 2002), who indicated several major factors hampering progress in this area. The following factors found to be the most important bottle necks are discussed in the paper: (i) identification and utilization of new sources of resistance, not sufficient agronomic value of the used resistance sources; (ii) combination of earliness with LB resistance; (iii) complexity of genetic determination of LB resistance; (iv) combination of foliage and tuber resistance; (v) screening methods applied for resistance evaluation; (vi) cost of selection for resistance; (vii) lack of molecular markers (MAS) applicable to selection for LB resistance.   limitations, Phytophthora infestans, potato, resistance breeding

A comparative study of different parameters calculated for foliage resistance of potato to Phytophthora infestans (Mont.) de Bary was conducted on the data for 27 cultivars and one prebreeding clone in field assessment in 2003 at BAZ Groß Lüsewitz. Relationships between the parameters and maturity were determined by linear regression. The strongest associations with maturity were found for the relative area under the disease progress curve (RAUDPC), delay of attack, and attack on a determined date (r2 = 0.47-0.52). The least association with maturity was found for foliage blight resistance at Groß Lüsewitz, FBRGL (r2 = 0.03), calculated by using a maturity-dependent section of the disease progress curve. The apparent infection rate (AIR), RAUDPC and delay of attack could only explain below 50% of variability of FBRGL. The method for calculation of foliage resistance in breeding developed at BAZ and named FBRGL is described in detail, and the usefulness of the different methods for evaluation of resistance, management of plant protection and breeding is discussed.

Despite many breathtaking breakthroughs in the area of crop genetics and genomics, plant breeding still widely depends on the methods that had been worked out almost a century ago. This is not because commercial plant breeders are overly conservative but because the new knowledge lacks efficient and economical tools that would permit their application in practice. Breeders desire supporting technologies that would facilitate laborious and time-consuming screening in the field and laboratory. In particular, resistance screening often cannot be performed satisfactorily as the necessary disease pressure and appropriate pathogen populations may be unavailable. In potato breeding, specific and often complex resistances need to be developed, at the same time maintaining high levels of quality and culinary characteristics. Therefore, it is worthwhile to revisit the facts that comprise the progress in genetics of disease resistance and to analyze current technologies of genotyping and marker assisted selection, with the objective to detect those parameters that limit the efficiency of methods for commercial application. Selection in potato for resistance to late blight will be highlighted as an example. Maps, genes and markers for resistance have been identified – how universal are they? Single genes and quantitative trait loci for race-specific and race non-specific resistance are known – how efficient is their use? Marker technologies based on polymerase chain reaction and DNA hybridization have been developed that are far more efficient than first-generation technologies – is their use in commercial breeding economical? By discussing these issues concepts will emerge that help to pave the way for marker assisted selection (MAS) in potato breeding. The most important parameters required for economical MAS include to have a clear idea of the traits to be selected for, to use proven, reliable markers, to have in place a robust system for the collection and management of DNA samples, and to use technologies whose total cost is below or equal to the cost of the conventional methods. The most striking advantages of MAS are that a breeder will obtain more information than by conventional methodology, the information will be more precise, field labour can be saved and in that way the breeding process will be intensified. The implementation of the new technology could lead to even closer collaboration of breeders and scientists. Possible disadvantages include the relative increase of laboratory and computer work within the breeding program, and possibly higher costs during the implementation phase of the new technology.

At SCRI, wild species and clones of Solanum tuberosum are assessed for resistance to late blight in order to study the genetics and breed for resistance. Glasshouse progeny tests for foliage and tuber blight resistance, using true seedlings, are described. These enable the rapid screening of accessions of wild species, and the selection of the most resistant progenies in a breeding programme within one year of crossing. Assessment of the foliage resistance of clones is carried out in glasshouse tests of whole plants in flower-bud, and field trials using infector plants inoculated in the glasshouse with a complex race of Phytophthora infestans. The glasshouse test provides a reliable method of identifying R-genes and the virulence characteristics of blight isolates. The field trial gives the best estimate of field resistance and is being used to develop marker-assisted selection. Both tests are used to study the inheritance of resistance, to locate quantitative trait loci (QTL) and R-genes, and to select the most resistant clones. The tuber resistance of clones is assessed by spray-inoculating whole, immature, field-grown tubers on the day of harvest. However when large numbers of clones are involved, e.g. in the location of QTL, this is impractical, so glasshouse-grown tubers are dip-inoculated.

Protoplast fusion was used to produce more than 500 symmetric interspecific somatic hybrids between wild Solanum species, which belong to the series Pinnatisecta, Etuberosa and S. tuberosum L. cultivars or potato breeding clones. The used genebank accessions of S. cardiophyllum and S. tarnii were resistant to Phytophthora infestans, while the accessions of S. cardiophyllum, S. tarnii, as well as of S. etuberosum, were also highly resistant to PVY (strains: PVYO, PVYN, PVYNTN, PVYC, PVYN Wilga). In most fusion combinations vigorous and genetically stable hybrid material has been selected. A number of interspecific somatic hybrids were fertile and could be backcrossed with cultivated potato. The use of detached leaf and tuber tests and mechanical inoculation, grafting and virus transmission by vectors, revealed that several somatic hybrids and backcross (BC) clones were resistant to foliage and tuber blight, as well as to PVY.

Green fluorescent protein (gfp) reporter gene and nptII marker gene were used to optimize Agrobacterium tumefaciens (agro) mediated transformation of wild Solanum genotypes resistant to late blight. Different genotypes of Solanum bulbocastanum, S. chacoense, S. microdontum and S. verrucosum were assessed for their regeneration ability on MS based media and for agro-mediated transformation. As the first step reporter genes were used to optimize transformation protocol for each species and then the transfer of genes involved in mismatch repair of DNA were attempted in Solanum chacoense. For transformation, either leaf or stem fragments were used. It was shown that gfp is a valuable and elegant tool for monitoring the efficiency of transformation or the occurrence of chimera in all genotypes. Transformation efficiency was dependent on a plant genotype. A number of genotypes have been successfully transformed and they expressed constitutively the bright green fluorescence of gfp without any side effects. The most recalcitrant species proved to be S. microdontum, which did not regenerate plants although different media and phytohormones had been used. The best protocol for S. chacoense transformation was also found to work in the transfer of msh2 genes. Msh2 isolated from Arabidopsis was used and transferred either as mutated (Apa) or antisense (As) gene. The integration of msh2-mutated gene into S. chacoense genome was demonstrated by PCR amplification and confirmed by RT-PCR for some of the putative transgenic clones. The implications of mismatch repair in homologous recombination and its importance for potato improvement are discussed. 

A study on the expression of resistance to Phytophthora infestans of wild potato plants grown in a climatic chamber, in a screenhouse and in the field was performed in two experiments. In the first experiment 12 populations of Solanum acaule were tested. Detached leaves from field-grown plants appeared to be less resistant than detached leaves from chamber-grown plants. In the second experiment resistance responses to inoculation with P. infestans of 24 Solanum species, grown in the field and in the screenhouse were compared. In 18 populations belonging to 11 species the predominance of resistant plants was found either when plants were grown in the field or when plants were grown in the screenhouse. Within 12 tested populations no difference in resistance was observed because of high susceptibility of plants, irrespective of grown conditions. Two populations showed the same level of resistance under both grown conditions.

New sources of Phytophthora infestans (late blight) resistance are studied in two groups of diploids: complex Solanum hybrids and clones of pure wild  Solanum species. In more advanced studies complex hybrids of Solanum verrucosum, S. phureja and S. microdontum were involved, which were intercrossed in various combinations. In this group, clones with resistance both in leaflets and tubers have been selected. In addition, highly resistant to late blight hybrids are outstanding in chosen quality traits. Resistance to P. infestans identified in the advanced hybrids has been successfully transferred into 4x level with various extent. The second group of sources recently included in research covers about 110 clones of five wild Solanum species (S. berthaultii, S. kurtzianum, S. michoacanum, S. ruiz-ceballozii and S. pinnatisectum). In 1999-2003 preselection of leaflets and tuber resistant clones was performed. Selected clones have been simultaneously characterized for male fertility and big pollen grains (2n) formation.

Thirty potato genotypes of different maturity were evaluated for tuber blight resistance both under laboratory and field conditions. From 2000 to 2003 replicated experiments were conducted with three potato cultivars registered in Russia and 27 tetraploid interspecific hybrids that were generated at VIR. Each genotype was assessed twice using laboratory tests, and its resistance was evaluated every year in a field trial. The results showed that four hybrid clones: 88-2, 95-23-3, 97-152-6 and 97-162-5 exhibited a superior performance of tuber resistance to Phytophthora infestans both in laboratory tests and field trials. Two cultivars and 10 hybrid clones were found susceptible to infection in all tests. Significant differences between the remaining 14 genotypes in tuber slice resistance, whole tuber resistance and the expression of resistance to tuber blight in the field were observed.

Reaction of 25 conventional and 63 determinate forms of faba bean to artificial inoculation with A. fabae and B. fabae was evaluated over five years. The severity of infection of faba bean with A. fabae was significantly higher than with B. fabae. This was observed for the both morphological types. Most of the conventional forms were less infected than the determinate forms, but it was more distinct for the A. fabae infection. Variable resistance reaction of cultivars was observed depending on pathogen and growth habit. In all years, conventional as well as determinate cultivars differed significantly in resistance to A. fabae. Significant variability of resistance to B. fabae was found only in one year for the conventional types and in another year for the determinate types of faba bean. It was found that some determinate cultivars showed higher resistance to A. fabae or B. fabae than most of the conventional forms, and some conventional forms were in the group of the most susceptible cultivars.      

This article is mainly addressed to plant physiologists and breeders. Nowadays, the cooperation between these two groups seems to be more important than ever before. Plant physiology offers better understanding of mechanisms and factors responsible for plant yielding. Thus, it might help to find proper traits for plant selection. Plant breeding proposes highly differentiated material for testing.

Resistance to powdery mildew, Blumeria graminis f.sp. hordei, is a major goal of many barley breeding programs. Resistance conferred by genes located at Mla locus is commonly used by barley breeders for effective control of powdery mildew. The use of molecular markers may facilitate barley breeding for powdery mildew resistance. In this study, bulked segregant analysis (BSA) was used to determine random amplified polymorphic DNAs (RAPDs) markers linked to Mla locus. Thirty one homozygous (17 resistant and 14 susceptible) F3 families from a cross between variety Pallas and single plant line E 1059-1-1 carrying gene at Mla locus were used as plant material. A total of 385 random 10-mer primers were screened to identify polymorphism between the appropriate resistant and susceptible DNA bulks and parents in BSA analysis. Only one PCR marker OPAA3400 (primer sequence: 5’-TTAGCGCCCC-3’), amplified in polymerase chain reaction (PCR) proved close linkage and was positioned in distance of 10 cM from Mla locus with 5.0 LOD threshold.

Based on the polymorphism of gliadin and glutenin proteins relationships of 45 cultivars and strains of winter wheat were evaluated. The cluster analysis showed a considerable variation of the investigated genotypes. The similarity indices were calculated using the Nei and Li formula. The genetic distances between the cultivars ranged from 1.00 to 0.12. The highest similarity index - SI=1.00- being proof of the identical physicochemical composition of storage proteins, was found for the pair Farmer and Elena. The groups of similar and genetically distant cultivars have been presented in the form of a dendrogram. The possibility of using the results obtained from the cluster analysis in breeding programmes has been discussed.

The giant grasses, some speeies in Triarrhena and Miscanthus, have high potential of biomass productivity and cou'd be used as a source of renewab'e raw materia' and energy. China is one of the most important distribution areas of these plants. An overall investigation on the high potential speeies and their geographical distribution in China is undertaken and the resultsare presented. T.lutarioriparia, ever named Miscanthus saccharif/orus, is an endemie speeies in China. It can grow to 6-7 m high and is being used as an important paper-making materia!. This speeies distributes in China in warm temperate regions from 28°36’ North latitude to 34°49’ North latitude; and from 110°41’ East longitude to 121°29’ East longitude. A cultivation trial shows that this speeies can grow over 3.5 m and over-winter safely in Braunschweig, Germany. The product quality, botanical and agronomie properties of this speeies are somewhat different to another hybrid speeies, Miscanthus × giganteus, the well-known speeies being cultivated and investigated in Europe. It is very interesting to integrate the newly introduced plant, T. lutarioriparia into the start materiais of Miscanthus breeding work. There are more information about other related plants given in this paper.

The maintenance of Phytophthora infestans cultures isolates from blighted potato, frozen in liquid nitrogen, was studied in two experiments. The effects of deep freezing and acclimatization pre-treatment at different temperatures on culture survival and stability of virulence and aggressiveness were evaluated. The best survival of cultures maintained for three months in liquid nitrogen was expressed, when cultures were acclimatized before freezing at 7˚C. The survival of frozen cultures was significantly worse in comparison with control combinations stored on rye-agar and rye-agar under paraffin oil for short time (in experiment I – 40 days, in experiment II – three months). The virulence spectrum of frozen cultures after thawing was more narrow than that one observed before culture freezing. However this virulence spectrum did not differ significantly from virulence range of control cultures. The level of aggressiveness of culture stored in liquid nitrogen did not differ significantly from control cultures as well. The virulence spectrum and aggressiveness level of cultures frozen in liquid nitrogen were significantly higher after two passages of thawed cultures on potato tissues than after single passage.

The objective of this research was to determine if variation for cold chipping exists in two breeding populations 4×-4× and 4×-2× potato hybrids. Twenty four potato genotypes of a population of 4×-4× hybrids (originated from crosses between parents with good chipping quality) were tested under field conditions at Młochów Research Center of the Plant Breeding and Acclimatization Institute over three years. Traits evaluated included: total tuber yield, marketable yield, starch content, chip colour after cold storage at 4°C, content of reducing sugars, tuber appearance. Out of 24 tested clones three have been selected with outstanding low accumulation of reducing sugars after cold storage (4°C), stable light chip colour and increased starch content. They were also described in trials as having moderate yielding ability, good tuber appearance and satisfied level of resistance to PVY, PLRV and Phytophthora infestans. Of four tested diploid parents in 4×-2× crosses, the DG 93-332 and the HT/HZ84-PH-151 were more suitable for creation of tetraploid generations combining low content of glucose with increased starch content, good yielding ability and satisfied tuber appearance.

The progress in breeding of grain and silage hybrids was analysed based on results of the official testing of maize hybrids during 20 years from 1981 to 2000. A number of maize hybrids tested significantly increased in 1990’s. Competition between seed companies resulted in big progress of both usage types (grain and silage). This progress was expressed by over 45% increase of the mean grain yield in all hybrid groups. At the same time farmers obtained much lower yields, which indicates a small ability to take advantage of hybrids potential productivity. Positive progress was obtained in limitation of lodging (almost 8%). Plant health was improved in many new hybrids but average data did not show significant progress in this aspect. Number of hybrids tested for silage was much lower than for grain. During 20 years nearly 38% increase of total dry matter yield (average for hybrids) was evidenced. Significant progress was observed in ear yields (52%), content of ears in total dry matter, which indicates a progress also in silage quality. Fodder units yield increased by 37.5% (average for all hybrids) during this period.

Changes in low and high molecular weight xyloglucan and pectic polysaccharide content were estimated during grain development in wheat (Triticum aestivum) cultivar Lok-1. Three grains differing in their final dry weight and position on the spike were selected for the investigation. The low molecular weight xyloglucan and high molecular weight xyloglucan were isolated by extracting in 4% KOH and 24% KOH, respectively. Changes in the xyloglucan content (low and high) showed an inverse correlation with water content. However, low molecular weight xyloglucan was more than high molecular weight xyloglucan at all stages of grain growth. Pectic polysaccharides also showed an inverse correlation, with highest content being in the smallest grain and vice versa. Increase in xyloglucan and pectic polysaccharide content coincided with termination of elongation growth thus suggesting its probable role in wall rigidity. It is suggested that cell wall is a dynamic compartment where reorganization occurs by turnover and alteration of wall polysaccharides.

Individual plants of 50 open-pollinated cultivars originated from 23 world-wide countries, 18 inbred lines and 9 wilde species and/or subspecies of rye were tested for the presence of sterility-inducing vs. normal cytoplasm, using conventional plasmotype/genotype interaction test. One  to fourteen random plants from each population were crossed as females to inbred lines representing nonrestorer genotype in both, Pampa and Vavilovii, types of sterility-inducing cytoplasm. The F1  and Bc1 or F2 progenies were scored for male fertility/sterility expression. The results showed that male sterility-inducing cytoplasm was common in the sample of a  world-wide rye population. Out of a total 629 single plants tested, 366 plants had sterility-inducing cytoplasm and all of them were derivatives of a cultivated rye populations. Among 50 cultivars and local populations of cultivated rye either normal or sterilizing cytoplasm was found in 9 and 19 populations, respectively, while 22 populations consisted of both plant types, with normal and sterilizing cytoplasm. A random sample of 61 male sterile Bc2 - Bc3 single plant progenies (a new sources of cms) developed from 28 populations were crossed to the L1 inbred line, acting as nonrestorer in Pampa and as restorer in Vavilovii cytoplasm, in an attempt to identify the type of sterility-inducing cytoplasm detected. Fifty of the 61 F1 progenies were male fertile indicating the presence of Vavilovii cytoplasm. Eleven F1 progenies were either male sterile or segregating but  backcrossing of male sterile segregates resulted in male sterile Bc1 and Bc2 progenies, thus  indicating that they all had Pampa cytoplasm. These progenies originated from plants of 6 South-American populations.

High crossability of tetraploid triticale (X Triticosecale Wittmack) with rye (Secale cereale L.) and relatively high fertility of the resulting hybrids make the triticale an attractive bridge species for introduction of wheat genes into rye breeding populations. It was found, with the use of in situ hybridization technique, that some 4x triticale materials bred in Radzików contain small wheat translocations, of both distal and intercalary type, into the rye 5R chromosome. The distal wheat translocation occupying less than 5% of the long arm was transferred into diploid rye, but a disomic line has not been established yet. Other wheat translocations of the chromosomes 1R and 5R were found in hybrids of 4x rye with 4x triticale. Besides the intergenomic crossing-over, at least one another mechanism of DNA rearrangements operated. Small intercalary two-dot signals of the wheat fluorescent probe were also found in one line on a rye chromosome different than 5R. Most puzzling was the „invisible” migration of wheat DNA to rye chromosomes, detectable on southern dot-blots, but not on the in situ slides. The wheat probe dot-blot signals were recorded for more than 1/3 of rye plants from the first back-cross of the 4x triticale × 2x rye hybrids to rye.

The European Secale Database contains passport data of 9,901 accessions. Twenty one European institutions contributed to ESDB. The biggest Secale collections are maintained in Poland, Russia  and Germany. Thirty three per cent of accessions maintained in Secale collections throughout Europe can be preliminary identified as duplicates. The ESDB is available on the Internet: www.ihar.edu.pl/gene_bank/secale/secale.html

The comparison of the population per se performance and the combining ability of 19 genetic resources and 5 adapted populations demonstrated that genetic resources might be integrated in hybrid rye breeding programmes without previous selection for yield. However, highly heritable traits like straw length and susceptibility to lodging should be improved before.

Ten open-pollinated cultivars, two strains of rye and Sl, S2, S3 progenies obtained after selection directed towards tolerance to nutrient deficit were used in the study. The aim of the study was to compare the genotypes of the above mentioned rye populations by electrophoretically characterised of their secalin patterns.The result showed that most of the tested rye cultivars revealed simi1ar but not identica1 electrophoretic patterns. Specific secalin patterns were obtained from all the cultivars, except cv. Arant and strain SMH 92. Differences in comparison to initial genotypes were observed in some rye populations in Sl and S2 generations, including additional polypeptide of molecular weight 43 kDa. It was not linked with rye tolerance to nitrogen and potassium deficit in medium.

Pampa cytoplasm has served as the main source of male sterility in hybrid rye breeding programs in Europe for 30 years and there is a need of introducing new CMS sources to prevent cytoplasm uniformity. Several CMS sources were discovered and studied in the former Soviet Union. The CMS sources in rye can be classified into two major groups, the P (Pampa) type and the V (Vavilov) type. The main goal of this study was to widen the “sterile” cytoplasm as a tool for rye hybrid development. ‘Koerntner’ represent the same or similar source of male sterility like CMS ‘CM’ and CMS ‘V type’. This source is genetically different from the sources of male sterility ‘Pampa’ and ‘D. Zlote’-1. In F2 progenies develop by self-pollination F1 plants, of P.6.2-1 × line 113, segregation according to the ratio three male fertile plants to one male sterile, was observed. The segregation ratio in F2 indicate that one or two recessive gene(s) are being involved in the interaction with mutated (S) cytoplasm to cause male sterility.

Head blight caused by Fusarium culmorum or F. graminearum affects all cereals including winter rye (Secale cereale L.). Besides yield and quality losses, grain is contaminated with the mycotoxin deoxynivalenol (DON) that is harmful to animals and humans. We analysed 76 self-fertile S2 lines and their corresponding testcrosses for head blight resistance and DON concentration in the grain by inoculating them with an aggressive isolate of F. culmorum at two locations in Southwestern Germany in 2000. Disease severity at both locations was low with mean ratings from 2.7 to 3.4 on a 1-9 scale (1=healthy), but still DON occurred in considerable amounts (11.4 - 15.0 mg kg-1). Genotypic variance was significant (P=0.01) in all instances, genotype-location interaction and error variances were more important for DON concentration resulting in a lower heritability of this trait. No association between S2 lines and their testcrosses was found for head blight rating or DON concentration (r = 0.33 and 0.19, respectively). The coefficient of correlation between head blight rating and DON concentration was low for the S2 lines and medium for the testcrosses (r=0.24 and 0.60, P=0.05 and P=0.01, resp.). The hybrid rye breeder should select predominantly on testcross performance. Selection for low head blight ratings should result in lower DON concentrations in the grain also. In later generations, DON should be analysed additionally to exploit the maximum selection gain possible.

Three hundred twelve inbred lines originated from the hybrid breeding program and two open pollinated cultivars: Zduno and Wibro as a standard were screened for resistance to Micodochium nivale during five years at Radzików. In each year about thirty to hundred inbred lines were evaluated under controlled condition in the cold chamber and parallel in the field. Selected lines were repeated in series of testing in subsequent years. Twenty three lines were tested during three years, sixteen during four years and seven during five years. Significant variation was found for disease rating among investigated inbred lines. Majority of them were severe damaged by M. nivale in all tests. None of tested lines showed an immune reaction to infection. Relative lowest damage were observed in standard cultivars, but a few inbred lines in each test showed the plant loses on the standard cultivars level. Five the best lines selected in 3 year testing confirmed their value in 4 year testing as well. One line which was tested during 5 years showed its high resistance in all series. This results indicate that selection of inbred lines with higher level of resistance to M. nivale is possible by multiyear testing. A positive correlation was found between the disease index of genotypes in cold chamber test and in field test. The coefficients of correlation were much higher in two years of testing than in three other.

Since 1967, over 2,500 rye (Secale cereale L. and S. montanum Guss.) populations have been studied at the N.I.Vavilov Research Institute of Plant Industry in order to determine genetic diversity of the crop with respect to leaf rust (Puccinia recondita Rob.) resistance. Plants possessing race-specific resistance to leaf rust were found in 51 accessions (cultivars, landraces and wild species). In 2000, a study of 420 rye accessions revealed stem rust (Puccinia graminis Pers. f. sp. secalis Erikss. et Henn.) resistant genotypes in 69 of them. Control of leaf rust resistance was found to be dominant monogenic in 44 accessions, and digenic in cultivar Chulpan 2. In some accessions, e.g. Avangard 2, Novozybkovskaya 4-2 and Derzhavinskaya 2, leaf rust resistance of individual plants was determined by one dominant gene, while in other plants of the same accessions it was determined by two dominant genes. In most resistance sources (Sanim, Chernigovskaya 3, Kharkovskaya 55) genetic control of the character is determined by the Lr4 gene, in Jmmunnaya 1 by Lr5, in Chulpan 3 and Immunnaya 4 by Lr6, in Novozybkovskaya 4-2 by Lr7, and in Lovaszpatonai by Lr8, in Yaroslavna 3 by LriO. Stem rust resistance is controlled by the dominant gene Sri. By pyramiding effective resistance genes two new winter rye cultivars have been bred.These are Estafeta Tatarstana (1999) and Era (2001) characterized by a high-level resistance to leaf and stem rust, to powdery mildew.

Economically important rye (Secale cereale L.) cultivars are highly susceptible to leaf rust caused by Puccinia recondita f.sp. secalis in Germany. Presently, only race-specific resistances are available, which are likely to lose their effect after prolonged application. To study possibilities of increasing the durability of resistance, a three-year field experiment was initiated in 2000. Seventeen differential lines, three susceptible standards, 30 segregating populations with one to four resistance sources and two full-sib families were grown at six locations under a high level of natural infection. All segregating populations were significantly more resistant than the susceptible standards. The resistance level, however, was under these conditions moderate only. The two full-sib families from Russia showed high resistance. Strong genotype × location interactions were observed indicating different race compositions of the local leaf rust populations.

Breeding relevant methods were developed or adapted for a comprehensive characterization of rye quality. In addition to classical chemical methods, necessary for calibration of NIR-spectrometer, a single kernel characterization system (SKCS) and a colour measuring instrument was used. NIR calibrations are calculated for yield, weight, size, shape and hardness (toughness) of rye grains, composition (protein, starch and arabinoxylans), colour and sprouting parameters.

The aim of study was to obtain rye strains of elevated total protein content and 1000-kernel weight with shorter and more rigid stalk comparing to standard cv. Amilo Translocation rye strains created due to distant crossbreeding of cv. Amilo (2n=RR=14) with wild form of Dasypyrum villosum (Crimea, Ukraine) (2n=VV=14) using in vitro cultures were study objects. F2 hybrids were three times back-crossed using parental rye pollen and then twice and three times self-pollinated (B3/F2 and B3/F3), study were sown in a micro-experiment in Laski on a good rye soil complex (ph 6.6) during 1998/1999 (98 strains) and 1999/2000 (123 strains) vegetation seasons. Strains under study were characterized with higher trait differentiation in the first year than the second. They usually headed 4-5 days after standard, although 5 strains among 98 ones studied in the first year and 9 strains among 123 ones in the second headed two days earlier. Comparing to standard, plants height was lower even by 20°cm in both years and their uniformity was usually higher, up to 3.0° and 3.8° respectively. Plant’s lodging was comparable to cv. Amilo at earlier generation; it increased to 1.8° above standard at the following one. Mean 1000-kernel weight of the standard was 36.8 g and 38.7 g, respectively in both years of study; however, it equaled 31.2-47.6 g and 33.8-41.6 g for strains. Only those strains exceeded cv. Amilo referring to protein content (N × 6.25) were selected (0.4-2.6% and 0.1-1.8%, respectively for years of study). Yielding, weight of hectoliter and sedimentation index that were below standard variety should be improved. Generally, better results were obtained in the second year, in which one strain yielded even by 2.8% higher than the standard. Strains selected for further breeding were less infected with black stem rust (up to +1.6°) than a standard rye variety. Selection coefficient amounted 31% and 21%, respectively in the first and second year of study.

It succeeded in developing a breeding relevant analytical tool for evaluation of meal and starch quality of single rye plants concerning their swelling, gelatinization and pasting characteristics. The pros and cons of well tried and new developed rheological devices and methods were examined closely.