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Flame-weeding is a very useful method for weed control, especially in organic production where the use of herbicides is prohibited. With this method heat sup­presses weeds in row within a second. Apart from this, heat also affects growing crop plants and surrounding soil. The aim of this paper was to determine the effect of different propane doses, on photosynthetic and polyphenolic (total flavonoids and anthocyаnins) pigments in soybean leaves, as well as the number of microorganisms in the soil. Soybean plants exposed to flame showed a different reaction to high temperature stress, which was reflected in differ­ent content of analyzed biochemical parameters, but the most responsive were anthocyanins. Actinomycetes turned out to be the most sensitive group of soil microorganisms affected by weed flaming, while fungi were the most tolerant.

This is the first report on the difference in the contents of the major quality compounds during development among cultivated ('Haschberg' cultivar and 'Ljubostinja' selection) and wild edible elderberry plants. Phenolics content in leaves (four stages) and fruits (unripe and ripe), as well as organic acids and sugars content in unripe and ripe fruits were determined. Quinic acid was the major organic acid in unripe fruits (especially in 'Wild' plants 16.7 g 100 g(-1)), while ripe fruits accumulated citric acid in the highest amounts (the highest was in' Ljubostinja' 10.2 g 100 g(-1)). 'Wild' elderberry plants had significantly higher sugar content in fruits, in general (2.2 unripe and in ripe 8.4 g 100 g(-1)), except for fructose content which was the highest in' Ljubostinja' ripe fruits (up to 6-fold higher). Tested elderberry plants had four major groups of phenolics in their leaves and fruits during development: phenolic acids (caffeic and caffeoylquinic acid derivatives), flavanone, flavonols (quercetin, kaempferol and isorhamnetin derivatives) and anthocyanins (mostly cyanidin derivatives).' Ljubostinja' had higher content of cyanidin derivatives in leaves in flowering stage and in all tested fruits (0.01% DW in unripe and 0.7% DW in ripe). Bearing in mind all tested quality parameters, 'Ljubostinja' selection had better quality of fruits, which position this selection as valuable resource for further cultivation and breeding of elderberry.

The aim of this study was to select Vicia genotypes with higher polyphenol contents and increased antioxidant activity, and to compare them with soybean, the most widespread and utilized legume species grown in the region. The examined legumes showed similar contents of total polyphenolics and tannins in between specimen, but differed greatly in their flavonoids and proanthocynidins levels. The content of total polyphenols ranged from 1.6 to 6.09 catechin/g dry seeds, and tannins from 0.26 to 2.98 mg of catechin/g dry seeds. The flavonoids levels in Vicia species were much higher compared with soybean, while the content of proanthocyanidins ranged from 1.5 (in soybean) to 62.3 mg of leucoanthocyanidin/g dry seeds (in vetches). The gallic and trans-cinnamic acids were identified as major monomeric phenolic compounds, and quercetin among flavonoids was found in all specimens. Catechin was detected in faba bean and vetches but not in the soybean. The values of the DPPH-test varied in a range between 21.1 and 89.6% of neutralized radicals, which correlated with the total polyphenolics and tannin contents. The faba bean specimens showed favourable traits - high total polyphenolic, flavonoid and proanthocyanidin contents, low total tannin content, and high DPPH-radical scavenging ability.

The purpose of this paper was to compare quality of seeds of two black and yellow soybean and the response of plants developed from these seeds to oxidative stress during vegetation and reproduction period. Content of carbohydrates: cellulose, starch, total and reduced sugars, as well as oil and protein content varied among all varieties, irrespective the colour. Bearing in mind all differences in seed quality, as well as response to oxidative stresses during development, black cultivars could be proposed as an excellent source of phenolic compounds (flavan-3-ols, antocyanins, genistein, glycitein, quercetin, laricitrin and isorhamnetin derivatives). Due to extreme fluctuation in precipitation amounts in the last years, information on the better performance of soybean varieties in oxidative stress conditions is of great importance to organic and conventional production of this cultivar.

The aim of this study was to characterize volatile and non-volatile compounds of rosemary from the North Adriatic region and to determine its antiproliferative activity, alone or in combination with radiomimetic bleomycin (BLM) on three malignant and one non-transformed human cell lines. Chemi-cal analysis of the volatile compounds revealed the presence of monoterpenes (93.8%), among which 1.8-cineol (32.9%) and camphor (15.5%) were the dominant compounds. Also, obtained results showed that the major polyphenolic constituents in rosemary extract were phenolic acids (rosmarinic acid and its derivatives up to 69.2 mg 100 g -1), as well as flavones and flavonols in the following order: lute-olin>isorhamnetin>quercetin>kaempferol>apigenin. Cell growth tests showed that rosemary extract alone exerted moderate antiproliferative activity, as well as a synergistic antiproliferative effect with bleomycin (EC 50 344.3-461.5 µg mL -1 and 58.6-292 µg mL -1 , respectively). The anti-tumor effect of rosemary extract in combination with BLM was much stronger, compared to BLM itself on the breast cancer cells. Through its proposed sensitizing effect, rosemary extract, in combination with the standard chemotherapeutics, could be used for the investigations of possible therapeutic modalities.

This study was undertaken in order to investigate the biological activity of chemically characterized Carum carvi essential oil (EO) and its effect on oxidative stress parameters in stored product pests. Gas chromatography-mass spectrometry depicted carvone (68.22 +/- 0.62%) and limonene (21.80 +/- 0.54%) as the major compounds of said EO. Different concentrations of EO were tested for fumigant activity and showed prominent results following a time-response relationship in both tested species. The changes in the antioxidative defense system, catalase (CAT), superoxide dismutase (SOD), and glutathione-S-transferase (GST) activities, as well as the level of lipid peroxidation (MDA) and the content of reduced glutathione (GSH) were estimated in time-dependent response. The results demonstrated that C. carvi could have a significant role in the future, as an environmentally friendly alternative for the management of stored product pests.

The purpose of this study was to analyze antioxidant systems among three invasive ragweed species, Ambrosia artemisiifolia L., A. trifida L. and Iva xanthifolia Nutt. Antioxidant capacity could be a possible marker of adaptation to variable environmental conditions, since change in amount of antioxidants represents one of the first responses to various environmental stimuli. Among investigated ragweeds, I. xanthifolia leaves had more pronounced guaiacol peroxidase activity (87.5 and 62.5%) and reduced glutathione content (2.3 and 28.8%) than A. artemisiifolia and A. trifida, respectively. However, super-oxide dismutase activity was invariable in all investigated plants (234.1-247.5 U g-1 fresh weight). The highest content of total phenolics, tannins, flavonoids and proanthocyanidins were detected in A. trifida leaves (up to 3.7-fold the amount of the others). According to antioxidant activity tests, investigated ragweed species could be presented in a scale: A. trifida gt I. xanthifolia gt A. artemisiifolia. Accumulation of non-enzymatic antioxidants and lower content of reduced glutathione point to different oxidative stress avoidance strategies of A. trifida when compared to A. artemisiifolia and I. xanthifolia within the same environmental conditions., Svrha ove studije bila je analiza antioksidantih sistema tri invazivne vrste: Ambrosia artemisiifolia L., A. trifida L. i Iva xanthifolia Nutt. Antioksidantni kapacitet može biti potencijalni marker adaptacije na promenljive uslove okoline, jer promena u količini antioksidanata predstavlja jedan od prvih odgovora na različite ekološke faktore. Među ispitivanim korovima, listovi I. xanthifolia imali su izraženiju aktivnost gvajakol peroksidaze (87,5 i 62,5%) i sadržaj redukovanog glutationa (2,3 i 28,8%) u odnosu na A. artemisiifolia i A. trifida, respektivno. Međutim, aktivnost superoksid dismutaze bila je nepromenljiva u svim ispitivanim biljkama (234,1-247,5 U g-1 sveže mase). Najveći sadržaj ukupnih fenola, tanina, flavonoida i proantocianidina detektovan je u listovima A. trifida (do 3,7 puta više od ostalih). Prema ispitivanim antioksidantnim aktivnostima, date vrste mogu biti predstavljene skalom: A. trifida gt I. xanthifolia gt A. artemisiifolia. Akumulacija neenzimskih antioksidanata i manji sadržaj redukovanog glutationa ukazuju na različite strategije izbegavanja oksidativnog stresa kod A. trifida u poređenju sa ostalim ispitivanim korovima u istim uslovima životne sredine.

The contents of soluble free phenolics (SP), PVPP-bound tannins (PVPP-P), flavonoids (TF) and proanthocyanidins (PA), as well as the DPPH-radical scavenging capability, of the whole grain of 17 different Triticum spp. accessions were analyzed. The contents of SP ranged from 976 to 2927 mu g CE g(-1), of PVPP-P from 335 to 1412 mu g CE g(-1) and of TF from 0.16 to 1.12 mu g RE g(-1) of dry whole grain. The presence of PA in the whole grains was not established. The values for DPPH-radical scavenging activity were rather moderate, under 40 % of neutralized radicals. A positive correlation between DPPH-activity and analyzed phenolics was recorded in twelve of the seventeen genotypes (r from 0.73 to 0.99). trans-Cinnamic acid was the major compound among acids and quercetin among flavonoids found in the wheat varieties. The data obtained should enable the selection of the accessions rich in biologically active compounds that could further be processed into functional food with possible health benefits associated with higher antioxidant properties.

The aim of the study was to evaluate in which way nine cultivars of sweet cherry fruit cope with postharvest, artificial inoculation with Monilinia laxa pathogenic fungus through changes in sugars, organic acids and polyphenolic compounds, as well as which phenolics compounds are crucial participants in coping with the disease. Contents of sugars in this study were (g kg(-1) dry weight): glucose 205-439 and 268-443, fructose 175-398.9 and 208.6-365.8 and sucrose 20-47.6 and 19.2-38.6 in healthy and infected fruit, respectively. Organic acids detected in sweet cherry cultivars were citric, malic, quinic, shikimic and fumaric acid and their content varied depending on cultivar and treatment. Only 'Burlat' accumulated tartaric acid after the infection. Of all phenolic acids, which content decreased in infected fruit, it is clear that only the more tolerant genotypes 'Merchant', 'Lionska', and 'Sue' enhanced content of 3-feruloylquinic acid (in healthy up to 93 and in infected fruit 105.3-139.1 mg kg(-1)). The most abundant anthocyanins were cyanidin derivatives (80-266.1 and 10-3700 mg kg(-1) in healthy and infected fruit, respectively). 'Burlat', 'Junska rana', 'Merchant' and 'Summit' dominantly had cyanidin-glucoside, while only infected fruit of 'Priusadebnaja' and 'Asenova rana' accumulated cyanidin-glucoside. 'Priusadebnaja', 'Asenova rana' and 'Lionska' had cyanidin-rutinoside. 'Lionska', 'Sue' and 'Asenova rana' had higher cyanidin and peonidin derivative contents in infected fruit (1.2 to 3-fold higher). Peonidine derivatives (peonidin glucoside and rutinoside), 5-carboxypyrano-cyanidin-rutinoside content mostly decreased after the infection (14.9-97.7 %). Bearing in mind obtained results, 3-feruloylquinic acid, flavonols and anthocyanins could be proposed as crucial participants in coping with the disease.

Losses of grain quality and quantity as a result of insect activity during storage impose the need for proper pest control. One of the major pests of stored wheat is the lesser grain borer (LGB), Rhyzopertha dominica. This pest is usually controlled with insecticides. However, there is recently a growing interest in the use of plant-based products in pest management. Plants are a rich source of active compounds and for centuries have been used for the control of harmful insects. This study was carried out in order to evaluate the effects of Satureja montana aqueous extract on LGB adults in contact and contact-digestive tests. The mortality of LGB adults during contact exposure to S. montana extract was low, regardless of the concentration (16.7-33.3% after 24 h and 30.0-33.3% after 48 h). After 24 h of contact-digestive exposure, the highest mortality was caused by 2% S. montana extract (23.3%), while after 48 h the level of mortality increased in all treatments with S. montana extract (0.5, 1, and 2%) and was 28.4, 28.4, and 41.7%, respectively. After 72 h of contact-digestive exposure, it ranged from 57.5 to 63.5%, while in the control it remained the same (2.7%). After 7 days of such exposure, it was 91.6-98.4%, depending on the concentration. Based on the obtained results, we conclude that S. montana aqueous extract caused mortality of LGB adults, the level of this mortality depending on concentration of the applied extract and duration of the experiment.

Soybean [Glycine max (L.) Merr.] cultivars (Meli, Alisa, Sava and 1511/99) were grown up to V1 phase (first trifoliate and one node above unifoliate) and then inoculated with Sclerotinia sclerotiorum (Lib.) de Bary under controlled conditions. Changes in L-phenylalanine ammonia-lyase (PAL) activity and isoflavone phytoalexins were recorded 12, 24, 48 and 72 h after the inoculation. Results showed an increase in PAL activity in all four examined soybean cultivars 48 h after the inoculation, being the highest in Alisa (2-fold higher). Different contents of total daidzein, genistein, glycitein and coumestrol were detected in all samples. Alisa and Sava increased their total isoflavone content (33.9% and 6.2% higher than control, respectively) as well as 1511/99, although 48 h after the inoculation its content decreased significantly. Meli exhibited the highest rate of coumestrol biosynthesis (72 h after the inoculation) and PAL activity (48 h after the inoculation). All investigated cultivars are invariably susceptible to this pathogen. Recorded changes could point to possible differences in mechanisms of tolerance among them.

The oxidative stress and antioxidant systems in soybean leaves and roots infected with plant pathogen Aspergillus niger were studied following treatment with different concentrations of cholic acid. Several oxidative stress parameters were analyzed: production of superoxide (O-2 (center dot-)) and hydroxyl radicals ((OH)-O-center dot), lipid peroxidation (LP), and superoxide dismutase (SOD; EC 1.15.1.1) activity, as well as the content of reduced glutathione (GSH). Results showed that inoculation with A. niger led to the increase of O-2 (center dot-) production and GSH quantities in leaves and (OH)-O-center dot in roots. The highest activity of SOD occured in infected plants treated with cholic acid in concentrations of 40 and 60 mg L-1 which ultimately led to a decrease in O-2 (center dot-) production. Inoculation with Aspergillus in combination with elevated cholic acid concentrations also increased (OH)-O-center dot production which is correlated with increased LP. These results may support the idea of using cholic acid as an elicitor to trigger hypersensitive response in plant cells. Use of cholic acid may also actively contribute to soybean plants defense response against pathogen attack.

The antioxidant activity and contents of various polyphenol classes in the seeds of seven soybean varieties of different seed color and one yellow seed cultivar, representing a reference genotype, were evaluated. Total polyphenols and tannins were determined after extraction of plant material with 70% aqueous acetone, and total flavonoids were extracted with methanol and acetic acid, whereas anthocyanins were extracted with 20% aqueous ethanol. In addition, isoflavone content and composition were determined using high-performance liquid chromatography analysis. Antioxidant activity of seed extracts was evaluated by the 2,2-diphenyl-1-picrylhydrazyl free radical scavenging activity assay. A positive linear correlation between antioxidant activity and contents of total polyphenols and anthocyanins was established. The highest antioxidant activity was observed in the extracts of black and brown varieties, which also showed high levels of all polyphenol classes examined. Yellow seed had the highest total isoflavone content (3.62 mg/g of dry material). The highest concentration of total daidzein was determined in black seeds (>2.0 mg/g of dry material), and the highest total glycitein and genistein contents occurred in the yellow cultivar (0.53 and 1.49 mg/g of dry material, respectively). According to our results, varieties of black and brown seeds could be of special interest not only for their large content of total polyphenols, ranging from 4.94 to 6.22mg of gallic acid equivalents/g of dry material, but also for their high content of natural antioxidants such as anthocyanins.

Changes in antioxidant systems in soybean [Glycine max (L) Merr., Fabaceae] genotypes infected with Sclerotinia sclerotiorum were studied 12, 24, 48 and 72 h after inoculation. Generation of superoxide and hydroxyl radicals was evaluated together with the production of malonyldialdehyde, main end product of lipid peroxidation. Several enzymatic and non-enzymatic parameters were monitored as well, such as the activity of antioxidant enzymes superoxide dismutase and pyrogallol and guaiacol peroxidases, reduced glutathione, soluble proteins and total carotenoids content. Results showed that genotypes expressed oxidative burst as well as different antioxidant systems in response to biotic stress caused by pathogen invasion. It has been confirmed that, although hypersensitive cell death is efficient against biotrophic pathogens, it does not protect soybean plants against infection by the necrotrophic pathogen such as S. sclerotiorum. Still, some genotypes showed distinctive and combined activity of several biochemical parameters which may point to further directions in exploring host-pathogen relations and lead to selection and production of new genotypes with higher levels of tolerance

Surface water, often used for irrigation purposes, may sometimes be contaminated with blooming cyanobacteria and thereby may contain their potent and harmful toxins. Cyanotoxins adversely affect many terrestrial plants, and accumulate in plant tissues that are subsequently ingested by humans. Studies were undertaken to (1) examine the bioaccumulation of microcystins (MCs) in leaves and fruits of pepper Capsicum annuum and (2) examine the potential effects of MCs on antioxidant capacity of these organs. Plants were irrigated with water containing MCs for a period of 3 mo. Data showed that MCs did not accumulate in leaves; however, in fruits the presence of the MC-LR (0.118 ng/mg dry weight) and dmMC-LR (0.077 ng/mg dry weight) was detected. The concentrations of MC-LR in fruit approached the acceptable guideline values and tolerable daily intake for this toxin. Lipid peroxidation levels and flavonoids content were significantly enhanced in both organs of treated plants, while total phenolic concentrations were not markedly variable between control and treated plants. Significant decrease in 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging capacity was noted for both organs. The levels of superoxide anion in fruits and hydroxyl radical in leaves were markedly reduced. Data suggest that exposure to MCs significantly reduced antioxidant capacity of experimental plants, indicating that MCs affected antioxidant systems in C. annuum.

The influence of soybean seed coat color and genotype on antioxidant capacity, phenolic content and isoflavone profile was investigated. Isoflavone content and composition of 21 seed samples - yellow, green, brown, black and rarely mentioned ocher and reddish, were determined by high-performance liquid chromatographic analysis. Antioxidant capacity and total phenolic content (TPC) were evaluated spectrophotometrically. Significant correlation between total isoflavone content and total genisteins was established in all colored groups. Total isoflavone content was in the range from 2.11 mg/g in a green wrinkled sample to 5.24 mg/g in yellow seed. It was found that black genotypes had the highest TPC and antioxidant capacity, which were significantly different (p lt 0.05) from other colored soybeans. The obtained interconnections among analyzed isoflavones can be used as a model for estimation of their specific content.

Monilinia laxa Aderh. and Ruhl. is the predominant causal agent of brown rot disease of stone fruit orchards, especially sweet cherries. The objective of this study was to identify reaction in response of nine genotypes cherry, with different pomological properties, against brown rot. These genotypes were harvested at commercial maturity from orchard in the Fruit Research Institute in Rimski Šančevi. The studied genotypes showed significant differences in terms of the occurrence of disease on fruits, both under artificial inoculation and infection in the field. Given the fact that sweet cherry fruits are prone to infection by a number of pathogens in the field, biochemical parameters were analysed on artificially inoculated fruits. Biochemical analysis of fruits determined significant differences in contents of total phenols, flavonoids and anthocyanins, as well as in antioxidant activity. It was genotype specificities and intensity of infection, as well as the interaction of the two that induced differences in the secondary biomolecules content and antioxidant activity. The majority of the genotypes examined showed high polyphenolics content, while under the infection, the content was significantly lower. Based on the results obtained, the secondary metabolites content can be used as one of the parameters for evaluating the resistance of sweet cherry genotypes to brown rot.

Brown rot (the causal agent: Monilinia laxa Aderh. and Ruhl.) is one of the most common and most destructive diseases among stone fruit, sweet cherries in particular. The objective of this paper was to determine different responses to brown rot among nine sweet cherry genotypes grown under the field conditions of infection in open field. In terms of enzyme and antioxidant activity occurring under infection, the studied genotypes showed significant differences in comparison with healthy fruits. However, at the biochemical level, soluble proteins (SP), superoxid dismutase activity (SOD), guaiacol peroxidase activity (GPX), pyrogallol peroxidase activity (PPX), lipid peroxidation (LP) and antioxidant activity (ABTS and TRC assays) in sweet cherry fruits was significantly affected by genotype, plant disease and interaction of these two factors. Significant differences between studied parameters of healthy and infected fruits were recorded in genotypes Junska rana, Merchant, Sue and III/VAL. The parameters studied can be used as a method of assessment of resistance to brown rot among sweet cherry cultivars., Mrka trulež (uzročnik: Monilinia laxa Aderh. i Ruhl.) je jedna od najčešćih i najdestruktivnijih bolesti koštičavih voćaka, naročito trešnje. Cilj ovog rada je bio da se utvrde različiti odgovori na mrku trulež ploda između devet genotipova trešnje, uzgajanih u uslovima prirodne infekcije na otvorenom polju. U pogledu enzimatske i antioksidativne aktivnosti koja se javila u uslovima infekcije, ispitivani genotipovi su pokazali značajne razlike u odnosu na zdrave plodove. Na razlike u biohemijskom pogledu uticali su: genotip, prisustvo biljne bolesti kao i interakcija ova dva faktora. Biohemijski parametri koji su pokazali razlike u uslovima infekcije su: sadržaj rastvorljivih proteina (SP), aktivnost supereksid dismutaze (SOD), aktivnost gvajakol peroksidaze (GPX), aktivnost pirogalol peroksidaze (PPX), lipidna peroksidacija (LP) i antioksidativna aktivnost (ABTS i TRC testovi). Značajne razlike između ispitivanih parametara zdravih i zaraženih plodova zabeležene su u genotipovima Junska rana, Merchant, Sue i III/VAL. Ispitani parametri se mogu koristiti kao metoda procene otpornosti na mrku trulež izmedju genotipova trešnje.

Changes in antioxidant systems in soybean and associated weeds (Ambrosia artemisiifolia L., Chenopodium album L., Convolvulus arvensis L and Sinapis arvensis L.) were studied in relation to treatment with herbicides linuron and dimethenamid in the field experiment. Differences in the total superoxide dismutase (SOD) and catalase (Cat) activities were observed in plants after application of herbicide formulation. Quantities of superoxide (O(2).-) and hydroxyl (center dot OH) radicals and malonyldialdehyde (MDA), reduced glutathione (GSH) and total polyphenols content were also determined. In addition to this, potential antioxidant activity of the plant ethanolic extracts were assessed based on the scavenging activity of stable DPPH free radicals. Results obtained suggest that plants investigated 1) expressed different antioxidant systems in response to herbicide treatment; 2) enzymatic and non-enzymatic protective mechanisms were complementary; 3) some weed species showed distinctive and combined activity of several biochemical parameters, such as Ambrosia artemisiifolia.

The antioxidant activity and contents of various polyphenol classes in the seeds of 20 soybean hybrids were evaluated. Total polyphenols, tannins and proanthocyanidins were determined after extraction of plant material with 70% aqueous acetone. In addition, flavonoid content was determined. Antioxidant activity of seed extracts was evaluated by DPPH free radical scavenging activity assay. A positive linear correlation between antioxidant activity and contents of total phenols, tannins and proanthocyanidins was established. The highest antioxidant activity was observed in the extracts of hybrids which have higher levels of all polyphenol classes examined. The most of the single-cross hybrids were poor in tannins which recommend them as good source for ensiled livestock feed. Results suggested that polyphenol content should be considered as an important feature of the soybean seed.

The contents and antioxidant ability of various classes of phenolic compounds present in the seeds of twenty soybean hybrids were evaluated. Total phenolics, tannins and proanthocyanidins were determined spectrophotometrically, after extraction of seeds with 70% aqueous acetone. In addition, the flavonoid contents were determined. The antioxidant activity of aqueous acetone extracts was evaluated by the 1,1-diphenyl-2picrylhydrazyl (DPPH) free radical scavenging activity assay. The highest contents of total phenolics were found in Serbian cultivar 1511 and Chinese cultivar LN92-7369, which also displayed the highest total antioxidant activity. Conversely, genotypes poor in phenolics also showed low levels of DPPH-radical scavenging activity. The results suggested that besides protein and oil contents, the phenolic contents should be also considered as an important characteristic feature of soybean seeds, and as a potential selection criterion for antioxidant activity in soybean.

Changes in antioxidant systems in sunflower (Helianthus annuus L.) inbred lines were studied in relation to different concentrations (0, 2, 3 and 4 mM) of oxalic acid. A great variability of the total superoxide dismutase (SOD) activity was observed in different genotypes after application of oxalic acid. Genotypes showing no change in SOD activity, as well as those with decreased and increased activities, have been found. The highest guaiacol peroxidase (GPX) activity was recorded in the leaves of Ha-26A genotype where the activity of SOD was low. In genotypes with increased GPX activity the malonyldialdehyde content was low. The increase in reduced glutathione content occurred in almost all of the genotypes studied with the increase in oxalate concentration. Some genotypes such as PR-ST-3B, showed distinctive and combined activity of several antioxidant systems. Also, obtained results for the content of total phenols support the idea of using soluble phenols as molecular markers and confirm the hypothesis of the defensive role of these compounds in plants.

Free proline content, superoxide-dismutase activity, and lipid peroxidation were measured in sixteen Yugoslav and introduced genotypes of soybean. More tolerant genotypes with higher free proline content and high superoxide-dismutase activity, and low lipid peroxidation were chosen. The selected genotypes could be used in field production, as well as in breeding.

Plant-growth promoting rhizobacteria (PGPR) elicit activation of the phenylpropanoid pathway in plants, which leads to phenolics production and enhanced antioxidant capacity. The purpose of this work was to assess the antioxidant activity of soybean plants, Glycine max L., inoculated with PGPR (isolates of Azotobacter chroococcum, Streptomyces sp. and mixture of these) during plant development, as well as the yield of inoculated soybean plants. PGPR applied in the experiment stimulated flavonoids and isoflavone synthesis, which enhanced the non-enzymatic antioxidant ability of the soybean plants. Moreover, PGPRs stimulated the accumulation of daidzein and genistin in soybean seedlings (5-fold and 2-fold compared to the control values, respectively). The mixture of PGPRs had a positive impact on the antioxidant activity (10-20 % higher activity) and yield components of soybean, which proposed this inoculum as possibly a potent bio-fertilizer in soybean production.

The effect of exogenously applied auxins on oxidative stress was studied in six rootstock selections of Prunus cerasus, P. mahaleb and P. fruticosa aiming at the effect of phytohormones on the level of the lipid peroxidation (LP). Standard rootstock PHL-A was used as a control. Leaves were collected on 0, 1st, 3rd and 7th day of inserting cuttings into the rooting substrate. Auxin mixture consisted of 0.8% α-naphthylacetic acid and 0.5% indolebutyric acid. Differences in intensity of the LP between auxin-treated and -untreated cuttings were examined. Almost all of investigated selections had lower LP intensity after auxin application (11.4-47.2%). The most prominent change was in leaves of PHL-A (49.2%). LP-lowering effect were recorded in leaves of P. fruticosa (56.9%) on 7th day and in P. mahaleb on 1st and 3rd day (5.9, 5.8%). Intensity of LP could be used as one of the biochemical parameters in further rootstock selection and production.

The purpose of this study was to investigate composition and content of phenolic compounds in seeds of common buckwheat (Fagopyrum esculentum Moench) cultivars from Western, Central and Southeastern Europe grown in the Balkan area, and to compare them with cultivars from the Balkan. Mostly detected hydroxycinnamic acids in seeds of the investigated cultivars were caffeic and chlorogenic acid derivatives. More than ten different flavanols were detected in the investigated seeds, based on which all tested buckwheat cultivars were divided into two groups: those with high propelargonidins (epiafzelechin-epicatechin) and those with high procyanidins contents. 'Novosadska' had the highest level of phenolic acids, proanthocyanidins, flavones and most of the flavonols. However, 'Bosna 1' and 'Bosna 2' Were highlighted with the greatest rutin content (up to 46 times higher than in other cultivars). All buckwheat cultivars had quite high antioxidant capacity (more than 80% of neutralized radicals), yet, 'Novosadska', 'Godijevo', 'Spacinska 1' and 'Bamby' excelled.

The correlation between intensity of lipid peroxidation and changes in antioxidant capacity of sugar beet plants (cv. `Drena') infected with Rhizoctonia solani Kuhn isolate ( AG 2- 2 IIIB group) was studied. Successful inoculation was confirmed by the presence of infection cushions in a cross section of leaf petioles. On the 7th day of the experiment, phenylalanine ammonia-lyase ( PAL; EC. 4.3.1.5) activity was in negative correlation with intensified lipid peroxidation process in leaves of sugar beet plants ( r= - 0.99). Also, in leaves and roots of inoculated sugar beet plants, total flavonoids content ( 35% and 20%, respectively) and 1,1- diphenyl- 2-picrylhydrazyl (DPPH)-scavenging activity ( 80% and 55%, respectively) were significantly reduced. Necrotic processes resulting from R. solani infection of sugar beet plants was followed by induction of plant phenolics metabolism; however, antioxidant capacity of these plants was reduced.

The lamina, main vein and peduncle anatomical properties of Centaurea sadleriana Janka plants from two populations, were examined using light and scanning electron microscopy. The indumentum was comprised of glandular and non-glandular trichomes of two types. The leaves were amphistomatic, isolateral, with strongly developed palisade tissue. Secretory ducts were observed along the phloem or sclerenchyma of large vascular bundles. Collenchyma alternated with chlorenchyma in the main vein and peduncle. Large groups of strongly lignified sclerenchyma were present along the phloem of peduncle vascular bundles. These features, together with thickened walls of epidermal cells and cuticle, numerous trichomes and thick-walled parenchyma in the perimedullar zone, were perceived as a xeromorphic peduncle structural adaptation. Non-enzymatic antioxidant compounds of phenolic origin were detected in small amounts and their respective content was higher in leaves compared to inflorescences. Compounds of phenolic orgin showed positive correlation with total potenial of antioxidant activity indicated by the DPPH assay. Greater total quantity of polyphenols and tannins was detected in leaves of plants from Zobnatica locality, while leaves of plants from Rimski Sanac were characterized by higher content of total flavonoids and proantocyanidins. Phytochemical analysis showed that dominant secondary biomolecules in inflorescences were phenolic pigments including anthocyanins and leucoanthocyanins, and free quinones in leaves.

Changes in enzymatic and non-enzymatic antioxidant systems in soybean (cv. Becejka) and maize (hybrid NS 640) seedlings were studied after inoculation with Rhizoctonia solani AG 2-2 IIIB. Enzymes such as plant peroxidases and phenylalanine ammonia-lyase were induced in the analyzed organs of both plant species. Nevertheless, increase in superoxide dismutase activity was recorded only in infected maize roots. After inoculation, lipid peroxidation was enhanced only in soybean plants. Seedlings showed ability to accumulate phenolic compounds, some of which correlated with disease intensity. A significant decrease in total carotenoid amounts was recorded in infected soybean and maize plants. After R. solani infection, the enzymatic and nonenzymatic antioxidant systems were more efficient in maize than in soybean seedlings.

Twenty F1 soybean progenies were analyzed for isoflavone content in order to investigate whether this attribute can be translated from parents to the corresponding hybrids. Content of total isoflavones in analyzed samples was ranged from 1.56 to 3.66 mg/g of dried soybean. Ten analyzed F1 progenies in one group had a mutual parent while the rest in the second group had randomly chosen parents. Contents of total isoflavones. total daidzeins and total genisteins were significantly different (p lt 0.05) in these two sample groups. A significantly strong correlation (p lt 0.05) between total isoflavone content in parents and corresponding F1 progenies was established (R-2 = 0.915). Similarity of the F1 progenies with a mutual parent was confirmed by Principal Component Analysis. Obtained results suggest that isoflavone content is the trait that can be derived from parent genotype to its F1 progenies and therefore the breeding of genotypes with better health promoting characteristics can be directed.

Twenty soybean cultivars, originating from the United States, Russia, Serbia, and China, were analyzed for their isoflavone composition, total polyphenolic content, and antioxidant activity. Isoflavones were extracted by aqueous methanol (80%) and analyzed by high-performance liquid chromatography/diode array detection. Precision and linearity of the applied method were within the standard limits of validation. The highest and the lowest total isoflavone contents were 4.59 and 1.45 mg/g of dried soybean weight, respectively. A significant difference (P lt .05) was found in isoflavone concentration among the different cultivars, but it was observed that origin is not a significant factor that could influence isoflavone content in soybeans. Total polyphenolic content varied between 2.13 and 3.45 mg of gallic acid equivalents/g of dried soybean weight. The free radical scavenging activity of soybean extracts assayed by 2,2-diphenyl-1-picrylhydrazyl in terms of 50% inhibitory concentration (IC50) ranged from 1.40 to 3.35 mg/mL. Negative correlation between total polyphenolic content and IC50 was observed, but there was no correlation between total isoflavone content and IC50. On the basis of this study, soybean cultivars with larger potency for biological activity could be recognized.

Anatomical analyses found that leaves of Euphorbia nicaeensis ssp. glareosa are isolateral, amphistomatous, with two layers of palisade cells on the adaxial and one on the abaxial side. Laticifers are present by vascular bundles, in palisade and spongy tissue. Stem laticifers are located in the pericyclic ring, adjacent to the phloem, in cylinder parenchyma and medullar rays. The structure of pleiochasium and dichasium peduncle is similar to the stem structure. Plants from typical steppe habitat show more xeromorphic features. Phytochemical screening of extracts showed presence of catecholes, flavonoids, tannins, saponins, free quinone derivatives and absence of anthocyanins, leucoanthocyanins, alkaloids, steroid compounds and essential oils. Our results showed that the examined taxon was partially susceptible to the action of reactive oxygen species, such as O(2)center dot(-) and center dot OH. The higher quantities of ROS thus provoked an antioxidative response from the plant, both in an enzymatic and non-enzymatic manner. Stable anatomical structure, presence and distribution of laticifers and effective antioxidant properties when exposed to ROS, make Euphorbia nicaeensis subsp. glareosa potentially interesting for further pharmaceutical and phytochemical examinations.

Twenty soybean cultivars were analysed for their antioxidant activity and content of isoflavones, flavonoids and total polyphenolics. After extraction with methanol-water (8:2, v/v), isoflavones were determined by C-18 reversed phase high-performance liquid chromatography coupled with photodiode array detector. Flavonoid and total polyphenolic content contents were established spectrophotometrically. Antioxidant activities of soybean extracts were measured using 2,2-diphenyl-1-pycril-hydrazil free radical method. Cultivars most abundant in polyphenolic compounds expressed the highest DPPH-radicals scavenging activities. Genotypes with low content of total polyphenolics, expressed approximately half of the activity of polyphenolic-rich genotypes. Correlation between total polyphenolic content and antioxidant activity was found to be statistically significant (p lt 0.01). At the same time, no correlation was found between content of isoflavones and antioxidant activity or content of flavonoids and antioxidant activity. The results suggested that total polyphenolic content could be considered a useful marker of antioxidant activity in soybeans and, beside isoflavone content, one of the criterions for identifying the cultivars with better health-promoting characteristics.

The growing clinical interest and use of soybean-based food products and extracts to increase dietary phytoestrogen intake have led to medical interest in the precise determination of the phytoestrogen composition of soybean products. We have analyzed the composition of these compounds in 20 domestic and introduced varieties of genetically non-modified soybean genotypes grown under the same agroecological conditions. The isoflavone content of soybeans cultivated in this region of Serbia has not been previously reported. The assays were performed, after extraction with methanol-water (8:2, v/v), by C-18 reversed phase high-performance liquid chromatography coupled with photodiode array detection. The total phytoestrogen concentration was found to be between 2.24 and 3.79 mg g(-1) dry bean weight. The total concentration of daidzein and its derivatives ranged from 0.96 to 1.82 mg g(-1), total glyciteines from 0.34-0.53 mg g(-1), and all genistein derivatives from 0.86-1.67 mg g(-1) dry bean weight. Given the high biological potency of phytoestrogens and their metabolic conversion products, our data suggest that phytoestrogen content screening could be a useful tool in the selection of soybean genotypes with improved health promoting characteristics.

Nitrate reductase and glutamine synthetase activity, as well as free proline and soluble protein content were measured in eight soybean parent genotypes and six F1 hybrids. The aim of this study was to determine variability and the mode of inheritance for these parameters, and point out the genotypes of interest for future breeding programs. Analysed genotypes and their F1 hybrids expressed significant differences in activities of nitrate reductase and glutamine synthetase enzymes, as well as in soluble proteins and free proline contents. Since mode of inheritance for all investigated traits was in most cases dominance or heterosis, it can be concluded that these parameters are under control of dominant genes. The obtained results suggest that genotypes with favorable traits, such as variety Linda, line 1511, and F1 hybrids (Linda x LN92-7369) and (Balkan x BL-8), could be of interest as a good starting material for further breeding programs., U radu je određena aktivnost enzima metabolizma azota nitrat reduktaze i glutamin sintetaze, kao i sadržaj rastvorljivih proteina i slobodnog prolina u osam roditeljskih genotipova i šest F1 hibrida. Cilj istraživanja je bio da se utvrde varijabilnost navedenih genotipova za odabrane parametre i način njihovog nasleđivanja. Ustanovljeno je postojanje statistički značajnih razlika između genotipova, kako u pogledu enzimske aktivnosti, tako i u količini rastvorljivih proteina i slobodnog prolina. Budući da su se ova svojstva nasleđivala pretežno dominantno, uz pojavu heterozisa, može se pretpostaviti da su pod kontrolom gena sa dominantnim dejstvom. Kao genotipovi sa povoljnim osobinama izdvojili su se roditeljska sorta Linda i linija 1511, i hibridi (Linda x LN7369) i (Balkan x BL-8), koji bi mogli poslužiti u uzgoju genotipova soje povećane tolerantnosti na sušu sa povećanim kapacitetom za usvajanje azota i sadržaj proteina.

This investigation was conducted in order to determine the degree of biochemical changes during accelerated and natural aging of sunflower seed. Five sunflower lines developed in Novi Sad, submitted to accelerated aging for three and five days, and natural aging of six and twelve months under conventional storage and controlled conditions, were used in these trials. Malondialdehyde, superoxide dismutase contents and peroxidase activities were studied. Lipid peroxidation and superoxide dismutase and peroxidase activities (especially pronounced in accelerated aging variant) were caused by both types of aging. The degree of seed damage and the ability of seed to resist the negative consequences of aging were influenced, beside duration of aging period, by type of storage and characteristics of sunflower lines.

The effect of five Azotobacter chroococcum strains and nitrogen content in nutrient media on callus growth of two Beta vulgaris L. cultivars were investigated, as well as the activity of nitrate reductase (NR), glutamine synthetase (GS) and glutamate dehydrogenase (GDH) in inoculated callus tissue. On medium with full nitrogen content (1 N) the inoculation with A. chroococcum strain A(2) resulted in the highest calli mass, while strains A(8) and A(14) maximally increased NR activity. On media with 1/8 N the highest effect on calli growth, GS and GDH activity had the strain A(8). The strain A(2/1) significantly increased callus proliferation on medium without N. Asymbiotic association between sugar beet calli and Azotobacter depended on genotype/strain interaction and was realised in presence of different nitrogen levels.