Agroecological Conditions In Serbia Research Articles

How Do Mixed Cover Crops (White Mustard + Oats) Contribute to Labile Carbon Pools in an Organic Cropping System in Serbia?

Sustainable farming is one of the priority goals of the "4 per 1000" concept with regard to the preservation of soil fertility and carbon sequestration. This paper presents a study on the use of a mixture of cover crops of self-grown oats (Avena sativa L.) and sown white mustard (Sinapis alba L.) in organic farming under the agroecological conditions of Serbia. The main objective was to identify sensitive carbon pools (microbial carbon and nitrogen, basal respiration and a number of specific groups of soil microorganisms) in organic farming with and without cover crops. The inclusion of a mixture of white mustard and self-grown oats as a cover crop led to a significantly increased biogenity of the soil compared to a control after only a few years of investigation. The number of microorganisms, soil respiration and microbial biomass carbon were significantly higher in the cover crop treatment compared to the control soil on an organic farm in Serbia. This is the first study in Serbia to investigate the effect of self-grown oats as a cover crop. Further research will incorporate a wider range of variables and factors in order to develop a sustainable and effective site-specific system for organic crop production in Serbia.

Chemical Composition, Antioxidant Potential, and Nutritional Evaluation of Cultivated Sorghum Grains: A Combined Experimental, Theoretical, and Multivariate Analysis.

Sorghum grain (Sorghum bicolor L. Moench) is a gluten-free cereal with excellent nutritional value and is a good source of antioxidants, including polyphenols, as well as minerals with proven health benefits. Herein, the phenolic composition, elemental profile, and antioxidant activity of sixteen food-grade sorghum grains (S1-S16) grown under agroecological conditions in Serbia were determined. Nine phenolic compounds characteristic of sorghum grains, such as luteolinidin, 5-methoxyluteolinidin, luteolidin derivative, luteolidin glucoside, apigeninidin, 7-methoxyapigeninidin, apigeninidin glucoside, and cyanidin derivative, were quantified. The antioxidant potential of the analyzed sorghum grains was evaluated by UV/Vis (DPPH, ABTS, and FRAP) and Electron Paramagnetic Resonance spectroscopy (hydroxyl and ascorbyl radical scavenging assays). The content of macro- and microelements was determined by Inductively Coupled Plasma Optical Emission spectroscopy. Theoretical daily intakes of selected major and trace elements were assessed and compared with the Recommended Daily Allowance or Adequate Intake. Sample S8 had the highest amount of phenolic compounds, while S4, S6, and S8 exhibited the strongest antioxidative potential. The sorghum studied could completely satisfy the daily needs of macro- (K, Mg, and P) and microelements (Se, Zn, Fe). Pattern recognition techniques confirmed the discrimination of samples based on phenolic profile and elemental analysis and recognized the main markers responsible for differences between the investigated samples. The reaction between hydroxyl radicals and luteolinidin/apigeninidin was investigated by Density Functional Theory and thermodynamically preferred mechanism was determined.

Assessment of Climate Change Impact on Maize Production in Serbia

Climate factors have an impact on plant life cycle, yield, productivity, economy and profitability of agricultural production. There are not a lot of studies on understanding of influence of climate factors variation on maize yield in agro-ecological conditions of Serbia. The aim of this paper is analysis of variation of climatic factors over a long-time period, as well as assessment of impact of the examined climate parameters on maize yield in two localities in the Republic of Serbia. For the analysis of climatic factors (temperature, precipitation, sunshine, humidity) in the region of Central Serbia and Vojvodina, the data of meteorological stations Kragujevac and Sombor during two thirty-year periods (1961–1990 and 1991–2020) were used. In order to determine the existence and strength of the relationship between the observed climatic factors and maize yield, a correlation analysis of these indicators for the period 2005–2020 years, was performed. In the period 1991–2020, the average values of temperature were annually increased for 0.046 °C in Kragujevac and for 0.05 °C in Sombor, and in the same period the average value of sunshine on an annual level was increased for 1.3 h in Kragujevac and for 5.01 h in Sombor, 2020 in comparison to average values in period of 1961–1990. The humidity was decline annually for 1.3 in Kragujevac and for 3.4 in Sombor in period 1991–2020 in comparison to average humidity in period of 1961–1990. The results of the correlation analysis showed that the maize yield was significantly lower in the years with expressed high temperatures and precipitation deficit. Based on these studies, established effect of climate change on maize yield and that this demand developing adaptation agricultural practice through creating maize hybrids and varieties with greater adaptability and improvement of agrotechnic measure.

Stabilnost prinosa zrna genotipova ozime pšenice

Bread wheat is one of the most represented field crops whose level and stability of yield is very important for the food security in Republic Serbia. In the paper was investigated stability of yield expression of 15 winter bread wheat genotypes in different agroecological conditions of Serbia, using the Additive main effects and multiplicative interaction (AMMI) model and GGE-biplot method of analysis. Aim of investigation was to determine which of applied analysis is superior in identification of the most desirable genotypes for cultivation in given environments. Analysis of variance showed that genotype and genotype-environment (G×E) interaction represent highly significant sources of variability in expression of grain yield. AMMI and GGE analyses were point out similar results and an indisputable conclusion is that multienvironment trials, besides routine usage of analysis of variance, must be analized with one of this two models, which combine analysis of variance and PCA analysis. AMMI analysis is simpler for interpretation and closer to the concept of view of the agronomical trial, while GGE analysis is more complex and gives more precise interpretation of "which-won-where", i .e. for defining of narrowly adapted genotypes in given environments. Thus, G11 as the genotype with highest average yield is narrow adapted to the environment Sombor and can be recommended, as well as in the environment 2 (Kruševac), while genotypes with modest requests (G2) rather can be recommended for cultivation in the environment 1 (Kragujevac), which is characterized by less fertile soil and a smaller amount and uneven distribution of precipitation.

Effects of autumn and spring primary tillage on soybean yield and 1000-grain weight in the agro-ecological conditions of Serbia

Soybean yield depends on the selection of cultivars, soil fertility, applied cultivation practices, and agroclimatic conditions over the years. High-quality and timely primary tillage is essential for stable development and high yields of soybean plants. The effect of autumn and spring primary tillage on soybean yield and 1000-grain weight was examined in a three-year study (2013-2015). The trial included cultivars with different maturity periods, developed at the Institute of Field and Vegetable Crops Novi Sad: Valjevka and Galina 0 maturity group, Sava and NS Maximus I maturity group, Rubin and Venera II maturity group. Trial subplots were prepared using different periods of primary tillage, which was conducted in autumn (November, 01–05) and spring (March, 25–31). The highest yields and 1000-grain weight were obtained after autumn primary tillage in all the three study years. Yield decrease by 2.72% to 38.91% and 1000-grain weight decrease of 1.33%-11.93% were recorded after spring primary tillage.

Production of Puno and Titicaca quinoa cultivars - cost benefit analysis

The aim of the paper is to test the effect of climatic conditions and management practices on the yield of two quinoa cultivars (Puno and Titicaca) and to analyze the economic benefits of quinoa productivity. The experiments were carried out during the 2017 and 2019 growing seasons in rain-fed conditions on a Serbian farm. The results of the two-year long experiments proved that the growing of the quinoa cultivar Puno and particularly the cultivar Titicaca in the agro-ecological conditions of Serbia would be remarkably successful from the aspect of agronomy (with the obtained average yield of 2.5 t ha-1 ) as well as from the aspect of economy (with the achieved average profit of 9,411 € ha-1 ). The obtained profit values indicate that the quinoa production in the Republic of Serbia would be more cost-effective than the production of the field crops which are already produced, particularly in the increasingly present arid conditions.

Aggressiveness and trichothecene production of Fusarium graminearum isolates from cereals in Serbia

The aim of this study was to assess variations in aggressiveness and trichothecene production of F. graminearum isolates originating from maize, wheat and barley in Serbia. Analyzing F. graminearum isolates (98) obtained from various agroecological conditions of Serbia over the period from 1993 to 2010, using the HPLC method, the following two chemotypes were observed: 3-acetyl-deoxinivalenol (3ADON) and 15-acetyl-deoxinivalenol (15ADON). A great diversity in the production of deoxinivalenol (DON) derivatives was observed. A majority of F. graminearum isolates, regardless of their origin (maize, wheat or barley) belonged to the 15ADON chemotype. The 3ADON chemotype was also detected, but in a significantly smaller number (13/98) samples, compared to the 15ADON chemotype (85/98). None of the tested isolates belonged to the NIV chemotype. The examined isolates showed different pathogenicity on barley leaf, wheat class and maize ears. The average pathogenicity of the tested isolates was the highest on barley leaf. It was observed that isolates originating from wheat had the highest average daily increase in mycelium growth rate (27.37 mm). Statistical analysis of the obtained results for mycotoxins synthesis showed that there was a highly significant statistical correlation between the production potentials of total DON, 3ADON and 15ADON in F. graminearum isolates belonging to various chemotypes. However, there was no statistically significant correlation between the aggressiveness of isolates and the production of total DON in isolates belonging to 3ADON and 15ADON chemotypes.

Rootstock effect on some quality characteristics of almond cultivars ‘Troito’, ‘Marcona’ and ‘Texas’

This study was carried out in order to determine the rootstock effect on content of oil and most abundant fatty acids (oleic acid and linoleic acid), oleic acid/linoleic acid ratio, total phenolic content (TPC) and radical-scavenging activity (RSA) of almond kernels. The experimental orchard was established in 2006 in Surduk (North Serbia). Cultivars 'Troito', 'Marcona' and 'Texas' were budded (grafted) on myrabalan plum seedlings and 'GF 677'. Results revealed significant influence of rootstock on evaluated characteristics. Except content of oleic acid and oleic acid/linoleic acid ratio all other parameters had higher values when cultivars were grafted onto myrabalan plum. As expected, significant differences were also determined among studied cultivars. Except content of linoleic acid, for all other parameters the lowest values were found in 'Marcona', while highest for 'Texas'. Obtained results can be used for improving of almond quality in agroecological conditions of Serbia.

Organic Fruit Production in Serbia

Organic fruit production and demands for such a production have been growing in Europe and worldwide. Agroecological conditions in Serbia exceptionally favour the development of organic fruit production, particularly of berries with raspberry varieties ranking first (raspberry from Arilje make up to 30% of the total world production of this species). Areas with organic orchards in our country amount to 2208.05 ha, ranking second, just behind the areas with cereals. The greatest areas with organic orchards are located in the regions of southern and eastern Serbia (1244.22 ha), then in Šumadija and western Serbia (830.61 ha). The Toplica District is a leading district in this most important region with the area of 1152.62 ha. Considering the fact that Serbia provides excellent natural capacities for the production of organic fruit, producers are still underutilizing these available natural resources, which represents a significant challenge for the future improvement of organic fruit production.

Variability of Dutch potato varieties under various agroecological conditions in Serbia

The study presents results of a three-year experiment of variability of different Dutch potato varieties in Serbia: Adora and Cleopatra (early), Innovator and Frisia (mediumearly) and Desiree and Kondor (medium-late). The research was conducted during 2008, 2009 and 2010, in three different soil and climatic locations: Zemun (100 m a.s.l.), Srbobran (86 m a.s.l.) and Guca (370 m a.s.l.). The four-repplicate field trials were set up using standard methodology according to the random block desing. The analysis of variance suggest that number of tubers per plant, number of market tubers per plant and total tuber yield were significantly fluctuating depending on genotype (G), year (Y) and the location (L). In addition to individual influences of different factors, their interactions were also pronounced (G x Y, G x L, Y x L, G x Y x L). In the three-year period average, the highest total yield was recorded in Zemun (35.80 t ha??), followed by Guca (29.32 t ha??), while the lowest average yield recorded was in Srbobran (27.38 t ha??). The highest average yield of tubers in the three-year period was recorded in the Cleopatra variety, followed by Adora variety, while the lowest average yield was recorded in the variety Frisia. Obtained results show that the highest yields over observed locations were recorded in early varieties that formed medium number of tubers per plant (Cleopatra and Adora) and medium late varieties (Desiree and Kondor) that expressed good resistance to high air temperatures and stress caused by drought.

Fusarium infection and deoxynivalenol contamination in winter wheat

In this paper, the incidence of Fusarium-infected grain of winter wheat and the content of mycotoxin deoxynivalenol (DON) was studied in two Serbian cultivars Simonida and NS40S, both harvested in 2014. The level of Fusarium contamination of wheat grain was determined using phytopathological techniques based on the standard methodology while DON was detected by enzyme-linked immuno-sorbent assay (ELISA). The incidence of Fusarium-infected grain ranged from 12 to 19% for Simonida and NS40S, respectively. Fusarium graminearum, as well-known producer of DON mycotoxin, was identified among Fusarium species. In addition, Alternaria spp. was isolated in high percentage, with an average incidence of 53% (Simonida) to 63% (NS40S).The average content of DON ranged from 424 ?g kg-1 to 1101 ?g kg-1 for Simonida and NS40S cultivars, respectively. Statistically insignificant negative correlation (r = - 0.18) was determined between Fusariuminfected grain and DON in the cultivar Simonida and statistically insignificant positive correlation (r = 0.11) in the cultivar NS40S. The mean levels of DON in studied wheat samples of both tested cultivars were not higher than the maximum permitted limit (1250 ?g kg-1) although the level of Fusarium-infected grain of both cultivars was relatively high. These results indicate that both wheat cultivars are susceptible to Fusarium infection and DON mycotoxin production in agro-ecological conditions of Serbia, but the cultivar NS40S being more susceptible compared to cultivar Simonida. In view of all stated above, regular health check of grains and developing strategies for integrated monitoring of incidence of Fusarium head blight are necessary preventive measures in protection of winter wheat.

Yield and quality of alfalfa in mixture with grasses in agroecological conditions of Vojvodina

Alfalfa is the most important forage crop in agroecological conditions of Serbia and it could be establish as a pure stand as well as in the mixture with grasses. The aim of field trial was to analyse forage yield and quality of pure stand of alfalfa, orchard grass and tall fescue and their mixtures in agroecological conditions of Vojvodina province. In both full harvest years annual yield of alfalfa pure stand was on the level as mixture with grasses, while pure stand of grasses achieved lower forage yield. This is a result of lower adaptation of grasses on weather conditions (precipitation and temperature), in particular weed invasion during the summer months. Apart from selection of adequate grass species and varieties in mixture with alfalfa it is also important to determine grass/legume ratio in order to achieve high forage yield and quality.

Mating populations of Gibberella fujikuroi (Sawada) S. Ito species complex isolating from maize, sorghum and wheat in Serbia

The status of fertility and distribution of mating populations in the G. fujikuroi species complex, isolating from maize, sorghum and wheat cultivated under various agroecological conditions of Serbia, have been studied. A total of 79 field isolates of Fusarium spp. in the section Liseola, which had been reciprocally crossed to standard testers (MAT-1 and MAT-2) from each of the four mating populations of the G. fujikuroi species complex, were selected for these studies. Twenty of 79 isolates belonged to the mating population A (G. moniliformis), 22 to the population D (G. intermedia), 17 to the population E (G. subglutinans) and 20 to the population F (G. thapsina). A mating type MAT-1 was dominant in the populations A (14 MATA-1 :6 MATA-2), D (13 MATA-1 :9 MATA-2) and E (10 MATA-1 :7 MATA-2), while MAT-2 prevailed in the population F (6 MATA-1 : 14 MATA-2). The obtained results indicate that the possibility of sexual reproduction of Fusarium spp., belonging to the A, D, E and F mating populations, is not so frequent phenomenon in Serbia as in other regions world-wide. Consequently, these species will be asexually reproduced under field conditions, particularly species belonging to the F population. These are the first results on the characterisation of three (A, E and F) out of four populations of the G. fujikuroi species complex present in Serbia.

An outbreak of Aspergillus species in response to environmental conditions in Serbia

The frequency and incidence of A. flavus and A. niger on barley, maize, soybean, sunflower and wheat grain, the abundance of European corn borer (Ostrinia nubilalis) moths and their interaction depending on weather conditions in the 2008-2012 period were studied. Under the agroecological conditions of Serbia, the species A. niger is more frequent than A. flavus, and concerning the crop species, its frequency is highest in kernels of sunflower, than soybean, maize, barley and wheat. A. flavus was extremely dominant on all plant species in 2012 regarding its frequency: 100% on soybean, 95.3% on maize, 65.2% on barley, 57.1% on sunflower and 45.8% on wheat. Furthermore, the incidence of A. flavus was higher in 2012 than in previous years. The uncommonly high frequency and incidence of A. flavus infestation of maize grain in 2012 were caused by extremely stressful agrometeorological conditions, high temperatures and drought over the period from flowering to waxy maturity of maize. The precipitation factor (Pf = precipitation sum / average monthly temperature) showed that 2012 was extremely arid in June (Pf = 0.57), July (Pf = 1.45), August (Pf = 0.15) and September (Pf = 1.42). European corn borer (ECB) was a second factor causing intensive occurrence of A. flavus on maize grain in 2012. The maximum flight of ECB moths was recorded as early as in July (5,149) and, as a result of this, high damage and numerous injuries were detected at harvest. Those injuries were covered by visible olive-green powdery colonies typical of A. flavus. In the chronology of A. flavus occurrence, these are the first data on its very high frequency and incidence under the agroecological conditions of Serbia. As intensive infections with A. flavus were rare in the past 50 years, the level of aflatoxins in maize grain was low.

Relationships of mycobiota on rachides and kernels of wheat

The frequency and incidence of fungi, as well as their interdependence, on rachis and grain of 14 wheat cultivars grown under 19 different agroecological conditions in Serbia, were studied. Out of the 23 identified fungal genera, a significantly higher number of species was isolated and identified from rachides (22) than from kernels of wheat (9). Fusarium and Alternaria species were the most frequent (up to 100 %) species on both, rachides and kernels, but the incidence of these fungi were higher on rachides than on kernels. The most frequent of the 14 Fusarium species were F. graminearum (96.8 % on both, rachides and kernels) and F. poae (93.8 % on rachides and 51.6 % on kernels). The frequency of F. verticillioides was significantly higher on rachides (64.5 %) than on kernels (19.4 %). A positive correlation (r = 0.5356 **) was established between the frequency of F. graminearum on rachides and on kernels. Furthermore, the frequency of Alternaria spp. was also statistically higher on rachides than on kernels, but the correlation was not statistically significant (r = 0.1729). The incidence of F. graminearum was negatively correlated with the incidence of Alternaria species in both, rachides (r = −0.3783 *) and kernels (r = −0.4863 **). These are the first data on the frequency and incidence of fungi on wheat rachides in Serbia, and they support the few data presented in the world literature. Results of this research could be useful for better understanding of pathways in a fungal infection and the improvement of wheat breeding for resistance, as well as, a proper application of fungicides in the wheat head protection.

Optimal timing of fungicide applications for the control of Podosphaera leucotricha, the causal agent of peach rusty spot in Serbia

Peach rusty spot has regularly occurred in Serbia in recent years, causing significant economic losses in the production of late maturing cultivars (Summerset, Suncrest, Fayette and O?Henry). Concerns regarding the etiology of this disease have been solved using molecular identification and cross-pathogenicity tests, which have proved that peach rusty spot is caused by Podosphaera leucotricha. The usual recommended strategy for its control, by multiple treatments starting from petal fall phenophase, has not proved satisfactory in agro-ecological conditions in Serbia. After testing the fungicide efficacy, a three-year study was carried out to determine the precise treatment terms and make the control of P. leucotricha more efficient. The investigation was conducted in the conditions of natural infection in a Summerset cultivar orchard at the locality of Bela Crkva, during the period 2006-2008. Nine different variants of both single and mixed treatments were tested, covering six defined peach growth phenophases - from green top, until the phenophase of second fruit falling. In the conditions of high levels of natural infection in the control plots, in all three investigation years the most efficient was the variant in which kresoxim-methyl was applied three times: in green top, pink bud and full bloom phenophases (91.69 - 91.92%), followed by the variant of treatments in the phenophases of rose bud, full bloom and petal fall (86.3-87.87%) and the variant of two treatments, performed in the phenophases of pink bud and full bloom (79.3-83.09%). The other tested variants showed significantly lower efficiency. The results obtained could significantly contribute to better peach fruit production, without losses caused by peach rusty spot which is commercially very important disease in Serbia.

A model of a successful utilization of a high genetic potential of maize yield

The principle of a system, defined as a ZP system, implying corresponding relationship among research, seed production and seed marketing, is that each segment within the system has its tasks and responsibilities, as well as, a clear interest. This system was established at the Maize Research Institute, Zemun Polje, almost half a century ago. The crucial characteristic is that this system encompasses obtained results of scientific accomplishments (patent - a released hybrid), optimal utilisation of the environmental conditions, facilities for seed drying, processing and packing, staff and transport capacities. The ZP system provides the economic interest of all participants in studies and the maize seed production. The fundamental base of the quality seed production within the ZP system is a multidisciplinary programme on maize breeding, as well as, 535 released hybrids with standard and specific traits. According to regulations in foreign countries, approximately 100 ZP maize hybrids have been released abroad. Agroecological conditions in Serbia are favorable for the development of the best genotypes and the production of basic and certified maize seed. There 10 processing plants that apply recent technologies in the maize seed processing procedure. Several generations of experts have been trained and gained experience within the maize seed production. Three seed testing laboratories have been accredited by the International Seed Testing Association. According to regulations in Serbia, monitoring of seed production under field conditions, and further on, during the processing practice is done only by designate authorities. This study presents one of successful systems of the seed production organization applicable in countries with similar conditions.