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The paper deals with usefulness of domestic and foreign cultivars and strains of spring durum wheat for pasta production. The grain used in the study came from a research field at the Felin experiment farm of the Agricultural University of Lublin. The results showed that the domestic cultivars are comparable to the foreign ones with respect to protein, gluten and ash levels in semolina, while being lower in yellow pigment. The high levels of semolina ash, as well as the low yellow pigment and high propensity to pasta dough darkening indicated that obtaining high quality pasta from grain grown in the Polish climate conditions is rather difficult for both the domestic and foreign cultivars.

The grains of 4 lines of hard wheat (Triticum durum Desf.) and of common wheat variety Sigma were examined. The content of phenolic compound and tocopherols that exhibit antioxidant activity was determined. Wheat plants were cultivated at two levels of chemical protection. The antioxidant properties of polyphenols and tocopherols were examined using free radical scavenging method against stable 2.2-diphenyl-1-picrylhydrazyl radical (DPPH·). Moreover, the antioxidant activity of standard compounds, like ferrulic acid, BHT and α-tocopherol was evaluated. Antiradical efficiency of polyphenols and tocopherols depended on time of reaction, genotype properties and level of chemical protection.

The grains of 4 lines of hard wheat (Triticum durum Desf.) and of common wheat variety Sigma were examined. The content of phenolic compound and tocopherols that exhibit antioxidant activity was determined. Wheat plants were cultivated at two levels of chemical protection. The antioxidant properties of polyphenols and tocopherols were examined using free radical scavenging method against stable 2.2-diphenyl-1-picrylhydrazyl radical (DPPH·). Moreover, the antioxidant activity of standard compounds, like ferrulic acid, BHT and α-tocopherol was evaluated. Antiradical efficiency of polyphenols and tocopherols depended on time of reaction, genotype properties and level of chemical protection.

Six winter triticale male sterile lines, based on the Triticum timopheevi cytoplasm, and 9 pollen parents were used in testing the effect of distance from the pollen source on the amount of pollen in the air and on the seed set in female ears, as well as in testing the effect of flowering synchronization on seed set. The experiments were carried out in 2001–2002. In both years the proportion of females to males was 3:1. The strip width of females and males was 8.1 and 2.7 m in 2001, and 18 and 6 m in 2002, respectively. Only one female line flowered synchronously with male parents, others flowered later up to 5 days. The highest amount of pollen on pollen traps and seed set in female lines was in the distance of 0.6 m from the ears of male parents. Starting from a distance of 2.6 m from male parents the amount of pollen on pollen traps and seed set in male sterile females was significantly lower, regardless of the strip width. The seed set depended on the flowering synchronization of females and males.

The paper presents studies on yielding of winter triticale breeding lines and doubled haploids (DH) in various environments. Twenty-five breeding lines and five DH lines were examined in field experiments carried out in six localities. Genotype-environment interaction (GE) was computed by the SERGEN programme. Among the studied genotypes only six (5 breeding lines and 1 DH) were characterised by stable yield. Out of 24 genotypes with significant GE interaction four were distinguished as intensive and four as extensive ones. No differences between breeding lines and doubled haploids were found in their reaction to environmental conditions.

Hitherto studies univocally point out the possibility of gene transfer from Agrotriticum hybrids and its utilization for triticale improvement. The aim of the study was to analyze the level of some yield elements of a hybrid between triticale (X Triticsecale Wittmack) and Agrotriticum (Agrotriticum sp.) as compared to standard triticale varieties in breeding experiments. It would allow evaluation of usefulness of the studied material in triticale breeding. The introgressed hexaploid winter trtiticale strain LAD 965/98 and three standard winter triticale varieties (Bogo, Lamberto and Woltario) were the main objects for the study. The studied strain was derived from crossbreeding of winter hexaploid triticale CZR 1132/90 [(Liwilla × Donar) × Liwilla] with Agrotriticum PPG 113 (Alef.) Mansf, from VIR in Sankt Petersburg, Russia, and followed by two back-crosses to CZR 1132/90 triticale. The hybrid plants were reproduced by self-pollination and subjected to selection for important quantitative and qualitative traits. The studied forms entered breeding experiments in Danko Ltd. and were tested in three vegetation seasons 1999–2000 (B2/F6), 2000–2001 (B2/F7), 2001/2002 (B2/F8), at several sites. The numbers of objects in the successive year’s experiments were 49, 41 and 41, respectively. The last experiment ranked as the preliminary state trial. The strain LAD 965/98 appeared to be valuable from the breeder’s point of view, because it gave high yields (from 79.5 dt/ha to 89.9 dt/ha) and was ranked at the first place (106.7% of standard), seventh (108.1% of standard) and eleventh (105.0% of standard), in respective years. Furthermore, as compared to mean values for the standards, it was distinguished by higher 1000-kernel weight, lower grain sprouting and lower infection by some pathogens causing leaf and spike diseases. Great breeding value of the triticale can result from the transfer of favorable genes originating from Agrotriticum (Agrotriticum sp.) or co-operation of genes forming its genotype, which is confirmed by the usefulness of achieving the reciprocal hybrids.

Two-factorial field experiment was conducted within experimental activity of Regional Advisory Centres. Yielding of three cultivars of winter triticale: Fidelio, Tornado, Prado was compared with that of winter wheat (Roma) all cultivated after potato and winter wheat on a very good rye complex (9 experiments).Moreover, yielding of winter triticale cultivars Moreno, Tewo and Vero was compared with that of winter rye (Esprit) all cultivated after potato, winter wheat and winter triticale on a good rye complex (3 experiments). Results of the research confirm high productivity of winter triticale cultivated after cereals. On better soils (very good rye complex) this cereal is competitive to winter wheat, whereas on light soils (good rye complex) its yielding is similar to that of winter rye.

Influence of N-fertilization and sowing rate on dynamics of plant mass accumulation, shoots number and shoot height was investigated for the winter triticale cultivar Fidelio in a three years experiment. The highest plant mass (green and dry) was recorded at sowing density of 1.5 millions of grains per hectare. The rate of 80 kg/ha of N-fertilization significantly increased mass of spikes per plant.

In the years 2000–2001 an attempt to determine the dormancy of seeds of five triticale cultivars was made. For that purpose germination was evaluated at 10, 15, 20 and 25°C, and seeds were sown at two dates, 4 and 14 days after harvest. The greatest effect of temperature was found when average germination time was determined (using Pieper’s method), the values of which decreased with an increase in temperature from 10 to 25°C. Under the same conditions a decrease in germination capacity at the first evaluation date was observed. When evaluation was done at a later date, a significant effect of weather conditions on the level of seed dormancy was found. Two cultivars, Kargo and Migo, were characterized by the highest level of dormancy, while cultivars Gabo and Wanad showed a low level of dormancy. The values of the estimated dormancy index were very low — from 0.06 to 0.15, which indicates its poor usability for the evaluation of triticale seeds, considering the fact that triticale is characterized by a low dormancy level.

Two-factorial field experiments were conducted at the Prusy Experiment Station near KrakĂłw from 1999 to 2001. They involved three spring triticale cultivars (Migo, Kargo and Wanad) and two seeding rates (400 and 500 kernels per m2). The soil type was degraded chernozem classified as the very good wheat complex. The grain yields of spring triticale varied between years and were affected by cultivars and seeding rates. Of the studied cultivars, Kargo gave higher yields than Migo (+8.2 dt×ha-1) and Wanad (+5.4 dt×ha-1). The grain yields of Kargo i Migo were increased by higher seeding rates. Cultivar had a significant effect on 1000-grain weight. Less apparent effects of cultivar were observed for the degree of tillering, length of ears and height of plants. No effect of cultivar was noted for the number of spikelets and kernels in an ear. Seeding rate significantly modified the components of yield structure and characteristics of spring triticale morphotype. Increasing seeding rate resulted in higher number of ears per area unit, higher 1000-grain weight and enhanced height of plants. In contrast, number of spikelets and kernels in an ear and its length were decreased.

The effect of two spring triticale cultivars (Gabo and Wanad) cultivation in mixture with wheat on the assimilative area of its leaves was studied in a field experiment conducted on a very good wheat soil in 1998–2000. Triticale share in the mixture sowing material constituted 75, 50 or 25%. Measurements of leaf blades were conducted at the phases of shooting and earing. In the conducted experiment, a bigger assimilative area of leaf blades was found in wheat at the shooting phase, whereas at the earing phase it was higher in the Wanad triticale. At the shooting phase, plants in the mixture with Wanad were characterized by a bigger leaf area. LAI index reached values ranging between 1.67 and 2.90, depending on the species, cultivar and mixture. At the earing phase Gabo triticale plants in mixtures revealed much bigger leaf area as compared to single species cultures, whereas Wanad cultivar plants had smaller area. LAI index at the earing phase reached the highest values in the mixtures with the smallest share of triticale (3.63–3.67) and in wheat pure culture (3.61). All the studied combinations of mixtures reached bigger LAI values in comparison to single species triticale cultures. However, no higher yielding of mixtures in comparison to single species triticale cultures was found.

Two microplot experiments with spring triticale var. Gabo and spring wheat var. Igna were conducted in Puławy in the years 1994–1996. Three plant densities (300, 450 and 600 plants/m2) were applied. At the full ripeness stage 20 successive plants from the middle part of rows in each plot were taken, and agronomic characters of stand (percentage of plants and shoots of different height, their productivity and the share in yield forming) were determined. At low sowing density spring triticale propagated much better than spring wheat. It produced shorter lateral shoots, especially of third and fourth order irrespective of a sowing rate. In spring triticale, the heads of lateral shoots were developed not as well as those of main shoots, whereas in spring wheat heading was more uniform. In both, spring triticale and spring wheat, the highest grain yield was produced by main shoot heads of well propagated plants, irrespective of population density.

The effect of sowing time, sowing density and nitrogen fertilization on grain yield and yield structure of new spring triticale cultivars were examined in experiments conducted in 2001–2002. It was found that: cultivars MAH 2300, MAH 2500 and CHD 400 well utilized medium nitrogen fertilization, above cultivars yielded higher at early sowing, no significant differences in yielding were found at plant densities ranging from 400 to 800 plants per m2 when density estimation was performed at full emergence stage.

This study was aimed at evaluation of the utility of ISSR markers as a tool for identification of inbred lines and for construction of genetic map of rye. Sixteen rye inbred lines and a mapping population composed of 94 individual F2 plants from the 544 × Ot0-20 intercross were used for the study. Twelve primers, which generated strong and reproducible amplification products, were selected out of 57 primers tested. The selected primers revealed 29 polymorphic bands which allowed the identification of lines and the estimation of their genetic diversity. A dendrogram developed on the basis of genetic similarities proved to be generally consistent with the pedigree data. Out of eight markers used for the analysis of F2 intercross population, six showed segregation consistent with 3:1 expectation for a single locus. The presented results of ISSR marker segregation suggest that this PCR-based method should be suitable for construction of rye genetic map. However, its efficiency seems to be comparable with that of RAPD.

The investigations included two cultivars and 8 simple and backcross interspecies rye (Secale sp.) hybrids differing in resistance to powdery mildew, brown rust and sprouting. Experimental material consisted of the seeds of plants tolerant and non-tolerant to N and K deficiencies, selected from above mentioned rye populations. The usual SDS-PAGE electrophoresis of storage proteins was used for determining genetic differences between them. The results showed genetic differences between the tested rye genotypes. Marked differences in protein structure, shown in the presence of polypeptides specific for each genotype, were found.

The aim of the studies was to determine the nature of GE interactions for grain yield of candivars and cultivars of winter rye. In 1998, twenty candivars and five cultivars were tested at 7 locations (Kowróz, Łagiewniki, Raszewy, Rogożewo, Smolice, Sroki and Szelejewo). In 2000, twenty genotypes were tested at four locations (Raszewy, Rogożewo, Smolice, Sroki). ANOVA showed differences among the tested candivars and cultivars in the both year, significant location effect and genotype × location interaction. Most of the genotypes studied showed high yield stability. The highest yield differences among the cultivars and candivars were recorded at Kowróz, Raszewo, Sroki and Smolice. These locations are good testing environments for revealing genotypic differences. Significant interaction between yield and location was observed only for the candivar SMH 142 in 1998 and for the candivar SMH 216 in 2000.

The investigations on interspecific hybrids of rye cultivars and wild species S. montanum, S. kuprijanovii, S. sylvestre and S. vavilovii, have been conducted for many years. The aim of these studies was the extension of variability of the initial plant material for rye breeding. The problem, which is often encountered in the forms obtained by interspecies crossing, is the crop and its quality. The intraspecific hybrids in species Secale cereale L. and interspecific hybrids of S.c. ssp. cereale with the Secale strictum ssp. africanum have not been used so far. The sib F2 generation of the reciprocal, intraspecific hybrids of Secale cereale L. ssp. cereale (cultivars) with the wild S.c. ssp. afghanicum, S.c. ssp. ancestrale and S.c. ssp. segetale and interspecific hybrids of S.c. ssp. cereale with the Secale strictum ssp. africanum were used in this study. Some of the tested hybrids possess a number of valuable traits. From the hybrids of rye cultivars with S.c. ssp. afghanicum and S.c. ssp. ancestrale, plants resistant to powdery mildew and brown rust were selected. Moreover, the selected resistant plants had long ears and the grain weight per ear was comparable to that in cultivated rye varieties. Selected hybrids with short straw and long ears can be used to breed the short straw varieties. Because of very broad leaves, the interspecific hybrids of S.c. ssp. cereale and Secale strictum ssp. africanum can be utilized as parental forms in breeding of rye pasture varieties. The results show that the tested hybrids can be very useful in rye breeding as an initial plant material.

The aim of the studies was to evaluate similarity and breeding value of a collection of 20 spring rye cultivars from different climatic and geographical regions. The following traits were analysed: plant height (cm), heading date, number of ears per 1m2, grain yield per 1 m2 (g), 1000 grain weight (g), and hectolitre weight (kg). For classification of studied genotypes into groups and for determination of genetic distance between groups, Ward’s clusting method was used. Since Ward’s method is not appropriate for assigning breeding value to particular traits, Haufe-Geidel procedure was applied for separation of means into non-overlapping homogenous groups. Variance analysis showed significant genetic variability for all studied traits. Haufe-Geidel’s test produced two (no. of ears/m2) to seven (1000 grains/ weight) homogenous groups. Cluster analysis of the spring rye genotypes the Ward’s method indicated strong intergenotype differentiation. Almost each of the genotypes from collection constituted a distinct homogeneous group.

Research carried out on hybrid rye in 2000–2002 showed that the Esprit cultivar was very susceptible to the infection of three Puccinia species and Rhynchosporium secalis (Qud.) Davis. The brown rust appeared to be the most important fungal disease every year. The losses in rye yield caused by the diseases ranged between 19.8% and 28.5%. Fungicides applied on the experimental fields (azoxystrobin and kresoxim-methyl + epoxiconazole) demonstrated their high and long lasting (6 weeks) effectiveness in control of the diseases. Economic effect of rye protection was high every year.

Hull-less mutants of spring barley obtained by mutation induction from the hull-less breeding line 1N/86 constituted the material for the performed studies. Two chemomutagens — N-nitroso-N-methylurea (MNU) and sodium azide (NaN3) were used for the treatment. Among the mutants 19 forms, representing different morphotypes and yielding ability, were chosen to field experiments performed in the years 2000–2002. The paper presents genetic variation of yielding and yield structure parameters of the mutants and their initial form. The results were statistically elaborated considering the years of the experiments and the analyzed traits. As compared to the initial forms, the mutants were characterized by a broad spectrum of variation for the traits. Generally, in the three years of experiments, the mutants showed lower yielding ability and decrease of the yield structure parameters. In spite of this, several mutants yielded above their initial form and exceeded it in the yield structure traits. They may constitute an interesting initial material for breeding programs of hull-less barley.

Barley doubled haploids (DH) were studied with the aim to detect linkage between genes conditioning pairs of metrical traits. Populations of DH lines derived from F1 and F2 hybrids from the cross Roland × Apex covered material for the study. The following traits were analysed: stem length, spike length, number of grains per spike, grain weight per spike and 1000-grain weight. On the basis of relations between means, variances and correlation coefficients in the F1DH and F2DH populations, the occurrence of linkage between genes responsible for stem length and genes conditioning spike length, grain number and grain weight per spike was recorded. Additionally, independent inheritance of stem length and 1000-grain weight was found.

The paper contains the results of statistical analysis of barley doubled haploid (DH) lines. Twenty eight DH lines (thirteen, 2-rowed and fifteen, 6-rowed) and two parental genotypes (2-rowed, Maresi and 6-rowed, Klimek) were studied in a series of field experiments repeated in five successive years, 1996–2000. The analysis was made using the SERGEN program (Caliński et al., 1998). The results of hypotheses testing concerning the mean yield of DH lines and their interaction with years allowed to distinguish three groups of genotypes: the best, average and the worst. In the first group two parental cultivars, two 2-rowed lines and two 6-rowed DH lines were classified, but among them cultivar Maresi and 6-rowed line, S10, were distinguished as stable genotypes, giving a high yield in all years. Among the remaining genotypes of this group only the cultivar Klimek appeared to be "intensive", i.e. yielding better under profitable climatic conditions of the years. Additional information about the genotypes was obtained by testing the contrasts of the means for 2-rowed and 6-rowed DH lines and the parental cultivars.

The study material consisted of seeds of four DH lines (two hull-less and two hulled lines) of spring barley. Before sowing the grains of chosen lines were irradiated for 60 or 180 minutes. A helium-neon laser working in the range of red light at the wavelength of 632 nm and power capacity 24 mW was used as a source of irradiation. The plants grown from untreated grains were a control combination. The influence of laser light on area of penultimate and flag leaves as well as parameters of yield structure were analyzed. The results obtained showed the dependence of leaves area on both the applied laser light exposure and plant genotype. In all the analyzed lines laser light had a significant biostimulating effect on leaf area. The effect increased with increase of a dose of irradiation. The reactions of particular DH lines differed greatly. The highest tendency to enlarge the size of penultimate and flag leaves was observed with hull-less lines R63N/14 and R58N/91. In general, laser light stimulated the yield structure parameters, although a small reducing effect of the treatment on some traits was also observed.

Genetic resistance to powdery mildew (Blumeria graminis f.sp. hordei) of 10 cultivars of winter barley from Polish Official List is presented. All cultivars have one or more genes for resistance in loci Mlra, Mla6, Mla13, MlLa and MlBw. All cultivars are susceptible to powdery mildew population in Poland. Only cultivars with gene MlLa have some level of resistance.

Genetic resistance for powdery mildew (Blumeria graminis f.sp. hordei) of 6 winter barley cultivars and 21 cultivars of spring barley from Polish Registration trials is presented. All winter cultivars have one or more genes for resistance in loci Mlra, Mla6, Mla7, Mlk and in one not yet identified. Twelve different resistance genes: Mla1, Mla3, Mla9, Mla12, Mlg, Mlk, Ml(IM9), Ml(St1) and mlo were detected at spring varieties. Only cultivars with gene mlo have a high level of resistance to powdery mildew in Poland.

Effect of the Bion 50 WG and Bio-algeen S 90 Plus 2 preparations on health and yielding of spring barley (cv. Atol), cultivated as a pure crop or as a mixture with oats, was analyzed in a field experiment carried out in Swadzim (near Poznań) in the years 2000 and 2001. Occurrence of the most important diseases was studied: leaf spot (Drechslera teres (Died) Drechs.), powdery mildew (Erysiphe graminis DC), rynchosporiosis (Rhynchosporium secalis (Oud.) Davis) and rust of barley (Puccinia hordei Otth.). The used bio-stimulators improved plant healthiness, the infection symptoms were reduced by 25–78%, depending on the disease and preparation used. The effect was prolonged till the second scoring at the milk stage, four weeks after the Bion application and eight weeks after the Bio-algeen treatment. At this stage, barley treated with the Bio-algeen became more susceptible to the powdery mildew. The cultivation of barley in mixtures with oat caused a remarkable reduction of the infection levels for the Rhynchosporium in 2000 and for the Erysiphe in 2001.The mixtures with oats yielded on the same level as the pure barley crop. Only the mixture with the naked oat (cv. Akt), which constituted 66.6% of the stand, had lower yield. The both biopreparations did not affect yield, either in pure stands or in mixtures.

The response of several spring barley cultivars to sowing rate and sowing date was investigated in a microplot experiment in the years 2000–2002. All the cultivars responded with increase of grain yield to the increase of sowing rate (up to 450 seed/m). The highest effects were recorded for the cultivars Sezam and Granal, the lowest one for the cultivar Blask. At the delayed sowing, the highest decrease of yield showed the cultivar Anabell, Granal and Sezam were most tolerant. Variability of the grain yield, in dependence on the studied factors, was related to differentiation in number of ears per unit area, as the seed number per ear and weight of 1000 seeds did not vary significantly.

In the years 1993–1996 pathogenicity of barley powdery mildew (Blumeria graminis f.sp. hordei) was investigated using the car — mounted Jet Spore Trap and benzimidazole technique. Frequencies of specific virulence genes were determined based on a number of colonies on the primary leaf of seedlings of 12 differential cultivars. Cultivar Igri was used as a susceptible control. In Poland in 1993–1996 the highest frequencies had virulences Va12 and Vg. Frequencies of virulences Va9, Va13, Va6, Va7 + k and Va7 + Ab increased in years. The highest coefficient of variability had virulence Va7 + Ab (Cv = 59.3%). Strong pathogenic influence of B. graminis f.sp. hordei population of from neighbouring countries on barley plantations in Poland was observed. In 1993–1996 virulences Va1, Va3 and Va7 + Ab were present, for which the corresponding resistances have never been used in cultivars grown in Poland. No Vo virulence was found.

Virulence frequencies of B. graminis f. sp. hordei in Poland in 1999, were determined using leaf samples of the susceptible cultivar Manchuria infected by powdery mildew collected in 12 locations. From leaf samples collected in each location, 22–45 single-spore isolates were obtained. Virulence of the specific single-spore isolates was determined based on their resistance reaction, on 32 differential cultivars. Virulences Vg + CP (91.2%), Va7 + Ab (94.1%), Vh (98%), V(La) (98.7%), V(Ru2) (98.7%), V(Bo) (99.6%), Vra (99.7%) were present in Poland, in 1999, with frequency higher than 90%. Virulences which were present with low frequency (below 50%) were: Va1 +? (29.7%), V(St1) + St2 (37.9%), Vat (38.9%), Va9 + k (38.9%), Va3 (39.9%), Va9 (45.6%). Virulences Va23, Vp, and Vo5 were not present. In 1999, a strong influence of pathogenicity of B. graminis f. sp. hordei population from neighbouring countries was observed on barley plantations in Poland. In 1999, virulences were present, for which their corresponding resistances have never been used in cultivars grown in Poland.

In the paper, oats cultivation in Poland compared to that in other countries of the European Union and in the world is outlined. Regional differentiation in oats cultivation in Poland in relation to both the share in cropping pattern and the yielding level has been revealed. The total area of oat crops in Poland in 2001 was 531000 hectares. Oat grain is mainly used as fodder, and only in a small part is utilized for consumption and industrial processing. The extent of oats cultivation in Poland is restricted both by the low yielding level and the high content of hull. However, it may be assumed that breeding of new hull-less cultivars can stop the tendency towards decreasing of oats cultivation and restore the interest in this cereal.

The field experiment was carried out in the Experiment Station Złotniki near Poznań. The influence of sprinkler irrigation (non irrigated, irrigated), cultivar (Jawor, Skrzat, Sławko) and nitrogen fertilization (0, 50, 100, 150 kg N/ha) on the oats yield, yield components and nitrogen productivity was investigated. Grain yield was influenced by interaction of irrigation and nitrogen fertilization as well as irrigation and cultivar. Irrigation increased panicle number and 1000 grain weight, N-fertilization increased panicle number and grain number in panicle for all cultivars. Nitrogen productivity was dependent on irrigation, cultivar and N-rate.

Studies on possibilities of grain maize cultivation in sub-montane conditions of the Sądecka Valley were conducted on -mountain type soil at Nawojowa (365 m a.s.l.) in 1998–2000 Two early cultivars: Eslia (FAO-170) and Jana (FAO-190) and 4 mid-early ones Ela (FAO-210), Mieszko (FAO-230), KLG (FAO-230) and LG 2190 (FAO-240) were used for the experiment. Mineral fertilization dosed 80 kg P2O5∙ha-1, 90 kg K2O∙ha-1 i 80 kg N∙ha-1P2O5∙ha-1, 90 kg K2O∙ha-1 and 80 kg N∙ha-1 was applied prior to sowing, while 40 kg N∙ha-1 was used as topdressing. Under the conditions of the experiment field maize emergence was weak; considerable plant losses between emergence and harvest caused that plant density during harvest was much lower than planned. The obtained grain yield, on average between 6.60 and 8.11 t per ha, should be considered as high. Considerable differences in grain yield occurred in particular years. The studies did not provide a consistent answer concerning the cultivar varieties selection because their yields were much differentiated in years. The highest grain yields were produced in the year when rainfall was low during growing season and the air temperature was higher than the many-year average. Grain water contents at harvest ranged between 26.1% and 45.6%, depending on the year and variety. Protein contents in grain ranged between 7.06 and 9.35%, depending on the variety and the weather course in particular years.

Combining ability of forty single crosses, which were obtained by crossing 5 inbred lines: 1327-1, 1311-5, 1169-21, 1315-14 and 9225 with 4 flint testers: K154, K296, K212, S41324A-2 and 4 dent testers: K324, K192, S41806A and S335 was investigated in 2002. The experiment was carried out at two locations in two-row plots, 5 m2 each using randomized complete blocks design with two replications. Data were recorded for lodging before harvest, tillering, dry matter content and grain yield. Significant GCA effects were detected for tillering, grain yield and SCA effects for all investigated traits. Significant interactions for GCA and SCA with locations were detected for grain yield. Line 922-5 was characterized by significant positive GCA effect for grain yield. Three hybrids: 922-5 × K296, 922-5 × S41324A-2 and 1311-5 × K212 showed the highest effect of interactions of SCA with locations for grain yield.

Relationships between physical and chemical characters of maize grain were determined together with assessment of productivity of dry milling and snacks quality in 38 cultivars, using the methods of correlation and of multiple and curvilinear regression. In total, 24 characters were investigated. A significant dependence of milling productivity on floating of grain, mass of hectolitre and seed hardness (in Brabender units) was found. Productivity of dry milling was determined, to the highest degree (68-78%), by the mass of hectolitre; crushing energy input (area of the Brabeneder diagram) and grain fat content. With increasing mass of hectolitre the total productivity of milling and yield of the best quality fraction rose linearly. Dependence of the productivity of milling on grain hardness was expressed as a curvilinear regression.

The field experiments on the influence of sowing density on grain yield of maize were carried out on a very good wheat type complex soil. Three maize cultivars were used for the investigation: early Esslia (FAO-190), medium-early KLG 2210 (FAO-230) and medium-late Mona (FAO-270). The maize was sown in three densities: 90, 110 and 135 thousand grains per ha. Mineral treatment dosed: 70 kg P2O5, 90 kg K2O and 80 kg N∙ha-1 was applied prior to sowing and 40kg N∙ha-1 as topdressing. The maize was hand sown with the interrows 70 cm wide. Weeds were controlled using the Azoprim herbicide after emergence. The plants were harvested in the last days of September every year. Plant density during harvest, for the average sowing density 90 thous; was 82.2 thous. pcs.∙ha-1, for sowing density 110 thous. was 100.0 thous. pcs.∙ha-1 and for 135 thous; density 113.8 thous. pcs.×ha-1. The grain water content at harvest was on an average about 35%. It was much lower in 1999, in the early variety amounted 22.1% and in medium-late 29.9%. Under the experimental conditions, increasing sowing density caused higher grain yields ranging between 7.79 and 10.27 t per ha, depending on cultivar. Weather course in the respective years affected the maize grain yield to a lesser degree. Protein content in grain ranged between 9.42% and 11.48% depending on the studied factors.

The seeds of five maize varieties differing in earliness were treated before sowing with red light emitted by electromagnetic wave generator. The pre-sowing seed stimulation resulted in significant increase of seed yield. The reactions of the varieties under study on seed irradiating were similar. The increase of seed yield was mainly due to the greater number and weight of seeds in a cob.

Chromosome engineering is an activity aiming at the introduction into crop plants of chromatin fragments with a desirable genes or loci, or changes in chromosome structure that increase crops’ end value. New chromosome constructs must compensate the absence of original chromosomes; to minimize genetic drag, in introgressions from wild relatives the amounts of transferred chromatin should be kept at minimum. The available techniques include chromosome fragmentation followed by random fusion of fragments into chromosome structures, or induced recombination. The fragmentation approaches produce many translocations but a majority of them are non-compensating. Recombination offers a good measure of control of the location and size of the introgression but requires screening of large populations. The selection of the appropriate technique should be based on specific goals and the available resources.

Improving resistance to preharvest sprouting is an important target of breeding programs, but this goal is difficult to achieve, because the preharvest sprouting resistance is a complex trait influenced by the weather before and during harvest time. The aim of this paper was presentation of some problems and perspectives of breeding forms resistant to preharvest sprouting. The investigation carried out in Plant Breeding and Acclimatization Institute Department of Cereals in the years 1996–2001 and a short review of some new papers in this domain are reported.

One of the results of recent reorganizations in Polish breeding is a remarkable reduction of financial support, which caused decrease in the number of running breeding programs. According to the data collected by the Research Centre for Cultivar Testing (COBORU), yield of the Polish winter wheat varieties is a several per-cent lower than that of foreign-bred ones. The variation in initial germplasm is of the same size for the Polish and the foreign breeding, since the cause must be related to the breeding procedures. The analysis of three years field experiments in six locations revealed a low frequency of strains significantly better than the remaining ones. This indicates a necessity to increase the number of lines entering examination process in the Polish breeding programs, in order to increase competitiveness of the bred wheat cultivars.