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The paper evaluated the tolerance of 19 wheat genotypes in the seedling stage grown in hydroponic conditions to induced osmotic stress. Desiccation osmotic stress simulating natural drought stress was induced using the chemical compound polyethylene glycol (PEG-6000). Tolerance of genotypes to induced osmotic stress is shown by stress indices: stress tolerance index (STI) and stress sensitivity index (SSI). The most sensitive to induced osmotic stress were the Pobeda and Ingenio genotypes, whose SSI index values were 2,49 and 2,10. The most tolerant to osmotic stress was the F1 progeny Dika x Donska with an SSI index value of 0,24. The highest values of the STI index were recorded in the Phoenix (1,11) and Ingenio (1,00) genotypes, while the genotypes Pobeda x Brigant (0,70), NS 40S (0,71) and WWBMC2 (0,76) had the three lowest STI index values. Five F1 genotypes stood out as superior in both optimal and osmotic stress conditions: Dika x Donska, WWBMC2 x Ingenio, Dika x Ingenio, Pobeda x Donska, Phoenix x NS 40S. The examined genotypes from the territory of Serbia (Pobeda, Zemunska Rosa and NS 40S) showed a high sensitivity to osmotic stress and a high potential for large biomass production.

The paper presents the results of testing of seed germination and initial growth of seedlings of four sunflower hybrids: 2950, 2951, 3007, 3009) at different temperatures: 20° C, 25°C, 30°C. In all hybrids tested, the highest germination of sunflower seeds was achieved at a temperature of 30° C; however, in two tested hybrids (2950 and 3007) no significant difference (p ≥ 0.05) was found between germination at a temperature of 30° C and 25° C. Correlation interdependence between germination and stem growth was positive and statistically significant (r=0.576p ≤ 0.05), while a positive but not statistically significant interdependence was also determined between germination and radicle growth (r=0.252p ≥ 0.05).

Harvest residues of sunflower, maize, oilseed rape and soybeans make up more than 50% of the total biomass yield and can also be used to obtain bioenergy. As a source of bioenergy, preference is given to harvesting residues that contain more cellulose and oil, such as soybean straw. Soybean breeding aims to create varieties with higher biomass and increased oil yield per hectare, as well as to create varieties that would be more suitable for industrial processing for the production of technical oils. In this study, the productive parameters of soybeans were investigated in two years, 2021 and 2022. The average yields of soybeans varied from 2.8 t ha-1 (2022) to 2.9 t ha-1 (2022). The total soybean biomass yield was 4.8 t ha-1, while the biogas yield was 384.5 m3 ha-1. The year had a significant impact on soybean production. The more favourable year for production was 2021, with significantly higher yields of grain, biomass and biogas, compared to 2022.

Drought is one of the main consequences of climate change that negatively affects plant growth and development, which in turn leads to a reduction in yield. The objective of this study was to investigate the effects of the physiological responses to the drought stress of maize plants (population IP3722), obtained from seeds of different ages (originating from 2012. and 2016) and different previous experience (the seeds formed in 2012. were more exposed to drought than in 2016.). Two populations responded to drought treatment by a significant decrease of shoot fresh and dry weight, this was followed with decrease leaf area and transpiration rate. Drought treatments enabled induction and differentiation of chemical signals of drought (abscisic acid-ABA and xylem pH) and hydraulic signals (leaf water potential), and monitoring of their activity on stomatal conductance. The data showed that hydraulic signals have the same impact on stomatal reactions in the D2012 and D2016 treatments. They also indicated that the chemical signal of ABA works toward stomatal closure, but that the effect depends on whether it originates from the leaf or the root. Leaf-originating ABA had more effect on the closure of D2012 stomata, while root-originating ABA and pH was more active in the D2016.

Areas used for the production of organic plants have been permanently increasing for many years, both in the world and in Serbia. This type of agricultural production in Serbia was performed in the area of 14,357.96 ha, and the leading role belonged to cereals. Since great attention has been paid to spelt wheat in the production of organic food, the organic system of agricultural production has been distributed over ever larger areas. Therefore, the objectives of this study were to present data on the areas cultivated with this type of cereals in Serbia according to regional distribution in 2012, 2015 and 2016 provided by the Ministry of Agriculture, Forestry and Water Management of the Republic of Serbia. Spelt wheat is cultivated on the area of 157.9 ha. The greatest areas are in Vojvodina (120.04 ha), followed by the areas in the south and Eastern Serbia (22.3 ha), Šumadija and western Serbia (14.1 ha), while the smallest production of organic spelt wheat is registered in Belgrade (only 1.5 ha). The varieties Nirvana and Ostro are the only spelt wheat varieties released in Serbia. Since spelt wheat has very good biological and agronomic traits, with the high nutritional and specific functional value of the grain, deserves more attention, particularly for growing within the organic farming system and production.

The scientific work presents the results of two year testing of the morphological and production traits of maize variety ZP Rumenka planted in three sowing dates. Investigations were performed on a calcareous chernozem in agro ecological conditions of northeast Srem. Subject of study were three sowing dates: March 31, April 10 and 20th of April. The results show morphological and productive maize traits that have the most important role in the yield formation. The traits are: stalk height (up to tassel), cob length, cob weight, grains per cob, cob share in the total mass and 1.000 grains weight. The values obtained are shown in the two year average and were compared over years of research. Variation caused by sowing period and variable weather conditions, were statistically analyzed using analysis of variance and LSD test. The results showed that sowing dates have a significant and very significant impact on the studied traits, which interacting with weather conditions, and particularly water regime, showed great variation. The thermal conditions of this area in a two year average and in each research year have shown that corn can be sown earlier (early April) than the most producers do. Any delay in sowing will significantly reduce the level of utilization of genetic yield potential of this variety. The best production results were achieved by sowing at the end of March. Even the very favorable weather conditions in the first year of investigation could not mitigate the consequences of the later planting dates. It should be opted for early sowing of maize considering the fact that the drought becomes common phenomenon in our main agricultural areas.

The influence of different amounts of nitrogen (30, 60 and 90 kg ha-1) on important soybean yield components (number of fertile nodes, number of pods per plant and weight of 1.000 grains), was examined in this paper. Experiment was carried out at two different localities (Maize Research Institute Zemun Polje and the village Kloka-lower Jasenica) in 2009. Experiments were carried out through field plot trials, using split-plot in 4 replications. The results show that, on average, for both soil types, number of pods per plant and weight of 1000 grains increased using nitrogen dose of 60 kg ha-1 for 5.2 and 3.8% and the number of fertile nodes to the variant of fertilization with 30 kg ha-1 of nitrogen for 3.8%. The amount of 90 kg ha-1 N gave lower values of the number of pods per plant compared to the control.

The aim of this study was to evaluate the following parameters for the ear height of silage maize: variability of inbred lines and their diallel hybrids, superior-parent heterosis, components of genetic variability, heritability and combining ability on the basis of a diallel set. The two-year four-replicate trail was set up according to the randomized block design in the location of Zemun Polje. The analysis of components of genetic variance for ear height indicates that the additive components (D) were lower than dominant components (H1 and H2) of genetic variance, while the frequency of dominant (u) and recessive genes (v) for this observed trait shows that dominant genes prevailed. The results of the Vr/Wr regression analysis point out to superdominance of ear height inheritance. The analysis of variance of combining abilities shows that there were highly significantly positive values of GCA and SCA for ear height in both years of investigation. Non-additive gene effects played an important role in inheritance of this trait, which was illustrated by the GCS to SCA ratio < 1.

According to the analysis of variance, a genotype, year and a genotype x year interaction significantly affect variability of the trait number of kernel rows per ear. This number was the highest in the silage maize inbred lines ZPLB402, ZPLB403 and ZPLB405 in both years of investigation, resulting in low both positive and negative values of heterosis. The correct estimation of combining abilities is necessary in order to develop superior hybrids. This estimation was done on the basis of diallel hybrids after the method of Griffing (1956; method II, model I). The analysis of variance for combining abilities for the number of kernel rows per ear points to the significance of general and special combining abilities. The GCA to SCA ratio indicates that additive genes and the additive variance have a significant role in inheritance of this trait. Highly significant values of GCA for the number of kernel rows per ear for both years were found in the silage maize inbred lines ZPLB402 and ZPLB403, whereas inbreds ZPLB401, ZPLB404 and ZPLB406 had negative values. Highly significant positive, i.e. negative values of SCA for the number of kernel rows per ear for both years were found in the hybrid combinations ZPLB402 x ZPLB405 and ZPLB402 x ZPLB406, i.e. ZPLB402 x ZPLB406, respectively. Highly significant effects of SCA in hybrid combinations that include both parents with low GCA values are probably a result of the interaction among additive genes in parents. .

The objective of this study was to evaluate following parameters of the ear length of silage maize: variability of inbred lines and their diallel hybrids, superior-parent heterosis and genetic components of variability and habitability on the basis of a diallel set. The analysis of genetic variance shows that the additive component (D) was lower than the dominant (H1 and H2) genetic variances, while the frequency of dominant genes (u) for this trait was greater than the frequency of recessive genes (v) Furthermore, this is also confirmed by the dominant to recessive genes ratio in parental inbreeds for the ear length (Kd/Kr> 1), which is greater than unity during both investigation years. The calculated value of the average degree of dominance √H1/D is greater than unity, pointing out to superdominance in inheritance of this trait in both years of investigation, which is also confirmed by the results of Vr/Wr regression analysis of inheritance of the ear length. As a presence of the non-allelic interaction was established it is necessary to study effects of epitasis as it can have a greater significance in certain hybrids. A greater value of dominant than additive variance resulted in high broad-sense habitability for ear length in both investigation years.

Recurrent selection methods were designed to improve the agronomic value of populations by gradually increasing the frequency of favorable alleles, while maintaining genetic variability. To realize these objectives, progenies are developed, evaluated, selected and recombined in a repetitive manner. Populations improved by recurrent selection are excepted to be agronomically superior to unimproved versions and have enough genetic variability for the traits under selection to allow these populations be used for medium or long-term selection. The performance of hybrids is associated with the level of heterosis, i.e., to the superiority of hybrids over their inbred parents. To exploit heterosis efficiently, populations are grouped into heterotic groups, where population crosses within and among groups produce low and high levels of heterosis, respectively. Hybrids are then produced by crossing inbred lines from different heterotic group. Recurrent selection programs should be integrated with hybrid breeding programs so that improved populations can be used as sources of inbred lines not related to that ones developed from recycled lines via pedigree breeding. The objectives of this paper are to present the effects of recurrent selection on hybrid breeding programs; to present the changes in heterosis following recurrent selection; and to compare intra- and inter population recurrent selection. Testcross half-sib recurrent selection (TCHSRS) is for hybrid breeding programs, improvement of population crosses as well as the populations per se should be as efficient as possible, because their rates of improvement are approximately the same as for as the derived hybrids and inbred lines per se, respectively. The use of TCHSRS rather then RRS or HSRS would be the suitable strategy to accomplish the requirements of hybrid breeding programs. .

The main task of breeding red clover, the second most important perennial forage legume, is to develop cultivars giving high forage yields of excellent quality. Goals set before red clover cultivar development are achieved by different breeding methods. Previous research has shown that the most important methods used in red clover breeding are mass selection, individual selection, recurrent phenotypic selection, the polycross method, hybridization, and polyploidy. Mass selection is one of the oldest methods and has proven highly effective in improving highly heritable traits. Individual selection and hybridization have been shown to be highly effective in increasing protein content. Recurrent phenotypic selection is very effective when breeding for resistance to some diseases and pests as well as when developing genotypes tolerant of the 2,4-D preparation. The main idea behind the polycross method is selection of clones with a good GCA to be used for developing improved synthetic cultivars. Since no tetraploid forms of red clover have been discovered in nature, induced polyploidy receives special attention in the breeding effort, mainly for the purpose of increasing forage yields. .

Micro satellites are DNA markers, based on the repeated nucleotide sequences number polymorphism. They belong to a group of PCR markers and are mainly used as an addition to other types of markers. Their characteristics and technical aspects of their application are discussed in the present study. Furthermore, some results obtained by the use of the micro satellite DNA in genetic mapping of plant genomes are also presented. Although micro satellites provide the identification of genotypes within a species, inadequacy of comparative mapping of different species is their serious blemish. .

In the present paper it was carried out an investigation of influence of meliorative application of fertilizers on grain yield, mass of hectoliter and 1000 kernel weight in some varieties of spring wheat, spring barley and spring oat, grown on acid soil. Small grains demonstrated different reaction on increased acidity of soil. Oat varieties were significantly more tolerant and achieved acceptable grain yield compared to spring barley and wheat varieties, that on such soil could be grown only with previous liming. Meliorative application of fertilizers increased the grain yield of wheat by 2.7 times, in barley by near 4 times and in oat by about 2.5 times in average for all varieties and treatments. The best results were achieved by joint application of NPK, lime and manure. .

The aim of this research is to study two important factors in wheat production (Triticum sp.) - sowing time and variety, specifically their influence on wheat yield and yield components: the number of grains per spike, grain weight per spike, 1,000-grain weight, and the hectoliter weight. The influence of sowing time and variety were determined based on the obtained data, which indicated the extent to which the significance of these factors manifest on certain components and wheat yield. The optimal sowing date is October 5th-25th. The variety itself cannot give a high yield without the application of all agrotechnical measures, to which we strive for primarily due to the high wheat importance. The experiment set up by the split-plot method in three replications examined three wheat varieties: Gabrio, Rapsodija and Basmati sown in two sowing dates: October 29th and November 25th. The results showed that all yield components (the number of grains per spike, the grain weight per spike, the 1,000 - grain weight, and the hectoliter weight) had the highest values in Rapsodija variety and were more dependent on the variety than to sowing time. The influence of the variety on the hectoliter mass was at a significant level. Wheat yield depended more on sowing time, and the influence of sowing time, variety, and interaction of these two factors on yield were statistically significant. The highest yield was registered in Gabrio variety (8.87 t ha-1), while the average yield achieved by this micro experiment was 8.46 t ha-1.

The aim of this study was to analyze the effect of increasing amounts of nitrogen on productivity of soybean genotypes under different agroecological conditions. The investigations were conducted on two locations: Maize Research Institute, Zemun Polje (tchernozem soil type) and Kloka village (private property, brown forest soil type). Field micro experiments were conducted by split-plot method in four replications. Given results show, on average for both soil types, increasing values of grain mass per plant and yield using 30 and 60 kg ha-1 of nitrogen for 7.1% and 7.5%, respectively. Fertilization variant using 90 kg ha-1 of nitrogen gave lower values of examined parameters compared to the fon (P60K60) for 5.4% and 5.7% respectively.

We analyzed variability and influence of investigated factors on grain yield of quinoa during three year period (2009, 2010, 2011). The experiment was conducted at two locations (Nova Pazova and Surduk), using two introduced genotypes of quinoa: KVL 37 and KVL 52. We detected that location and genotype had important impact. Grain yield varied according to years of study (1224 kg/ha to 1671 kg/ha). Results of regression and correlation analysis indicate on variation of the impact of plant height and number of plants per meter on the grain yield. Correlation coefficients were generally low and didn't show as significant. This indicates that these studies included small number of properties that can affect grain yield. In further work with this introduced species, more properties should be included.

This study encompass the investigation on combining abilities of six maize inbred lines and their diallel hybrids of F1 generation for dry matter yield of both, the whole plant and the ear. The analysis of combining abilities was performed following Griffing (1956) method 2, model I, without reciprocal crosses, while the analysis the genetic components of variance and the regression analysis were done after the model proposed by Hayman and Jinks (1954) and Mather and Jink (1971). Dominant gene effects in inheritance of dry matter yield of the whole plant and the ear were determined by the analysis of combining abilities. The role of these effects are also observable from the analysis of genetic components of variations and results of the Vr/Wr regression analysis. The inbred line ZPLB 406 was the inbred with the highest GCA effects. .