SUMMARY
Oats are of great economic importance thanks to the high nutritional value of the grain. In this study, the productivity of oats was analyzed in two varieties: control (variants without digestate) and in the variant with digestate, during 2021-2022. The following parameters were tested: plant height, number of grains per panicle, grain yield per hectare and protein content. Highly significant positive correlation coefficients were found between grain yield and number of grains per plants (r=0.68··) and grain yield and plant height (r=0.59·). The results showed that year and digestate had no statistically significant effect on oat grain yield. The obtained values for grain yield were statistically significantly higher in the variant with digestate compared to the control variant. The digestate had a significant effect on the increase of oat yield and yield parameters, therefore its application in the oat crop is recommended.
Keywords: oats, year, digestate, yield components, protein content
INTRODUCTION
Oats (Avena sativa L.) is a real cereal that is of great economic importance due to the grain that has a high nutritional value, which is why it has been declared a functional food. Oat grain is desirable in the diet because it is responsible for numerous health benefits (Buric et al., 2023). In human nutrition, peeled oat grain is used in the form of oatmeal, semolina and oat flour, which is mixed with wheat to make bread and other bakery products (Figure la-c). Oat grain has 8.18% of digestible proteins and it has a higher nutritional value than maize (Glamoclija et al., 2015; Rajičić and Terzić, 2022; Burić et al., 2023; Popović et al., 2023). In Serbia, more it is grown as a forage plant in mixtures with legumes, and less for grain. In the world, the area under oats is decreasing at the expense of more productive grains, and according to FAO data, in 2022, it was grown on 9,562,497 ha. The average grain yield was 2,360 kg ha-1, and the total production was 22,571,618 tons. The largest areas under oats by continent were in Europe (5,390,227 ha or 56.37%) and America (2,387,873 ha or 24.97%). The highest average grain yield of 2,526 kg ha-1 and a total production of 13,614,876 tons were recorded In Europe. In Serbia, oats was grown on 14,503 on which 44,176 tons of oat grains were produced. The average grain yields of 3,046 kg ha-1 are 20.58% above the average of European countries, i.e. about 30% higher than the world's average yields (Popović et al., 2023).
These types of soils are characterized by different properties (chemical, physical, and physical-mechanical, productive). The agrotechnical and meliorative measures are determined based on the properties of the various soil types in the target of improving their productive capacity and agricultural production (Markoski et al., 2018; 2021a; 2021b; Boitumelo Mohlala et al., 2022; Dugalić et al., 2022; Stevanovié et al., 2023; Sekulić et al., 2023). For most types of soil in Serbia conditions, to achieve high yield and good grain quality, on average, 60-90 kg ha-1 of N, 60-90 kg ha-1 of P2O5 and 40-60 kg ha-1 of K2O pure nutrients should be applied. Phosphorus and potassium fertilizers are introduced in winter oats 50% in the basic tillage and 50% before sowing, while in spring oats all phosphorus and potassium quantities are introduced in autumn under basic tillage. In more humid regions, the amount of nitrogen for fertilization is added early in the spring during intense tillering (the first fertilization with half of the anticipated amount) and the second fertilization at the beginning of stem elongation with the remaining amount of nitrogen. In the case of spring oats in arid regions, the entire amount of nitrogen is given before basic treatment or pre-sowing preparation, i.e. without top dressing (Rajičić et al., 2020; 2021; Popović et al., 2023). The aim of this study was to investigate the effect of digestate on grain yield, productivity parameters and protein content of oat grain, over a two-year period.
MATERIAL AND METHODS
Study area
Experiments with spring oat variety NS Dunav carried out in Kovin, Pancevo municipality during 2021 and 2022, on chernozem soil in three repetitions. The oats pre-crop was soybean. For trial, an elementary plot of 25 m2 was sown. Soil cultivation was carried out according to the varietal standard growing technology for the tested spring oat variety. Digestate was used as supplement. The experiment was performed in two variants: 1) control variant without digestate and 2) variant with digestate. The entire amount of digestate is given during the pre-sowing preparation. Sowing was done in mid-February, Harvesting was done in early August with a harvester for experiments. The following parameters were analyzed: plant height (cm), number of grains per panicle, grain yield per hectare (t ha-1) and protein content (%). The yield was measured after harvest and recalculated to 14% moisture.
After harvesting, oat grains are stored in silos and dried to 14-15% humidity. Oat grain with a higher percentage of water after harvest is dried in dryers or directly poured into a silo that has an innovative mixing propeller that works with the help of SMART-THINGS, i.e. with the help of sensors as shown in Figures la and lb. The sensors monitor the humidity of the oat grains, report to the central sensor that directly with the help of the aggregate automatically blows moist or dry air, depending on the need in order to maintain optimal conditions for storing oat seeds (Popovic et al., 2023).
Meteorological Conditions
The meteorological conditions, monthly precipitation and air temperatures for 2021 and 2022 during the trial were taken from the Hydro-meteorological service of Republic of Serbia, Pancevo (Table 1).
Precipitation have a decisive influence on the yield components (Howarth et al., 2021; Lakié et al., 2021; 2022a; 2022b; Ljubičić et al., 2021; 2023; Nikolic et al., 2022; Dražie et al., 2022; Rakaščan et al., 2021; Dimitrijević et al., 2022; Filipović et al., 2022; Milunović et al., 2022; Popovic et al., 2011; 2020a-b; 2022; Kosev et al., 2022). Average temperatures in the growing season were 19.25°C in 2021. and 19.03°C in 2022., while total precipitation in 2022 was 351.4 mm and it was higher by 23 mm then in 2021, figure 1.
RESULTS AND DISCUSSION
Productive characteristics and protein content of oat in Serbia
The average value for the height of the plants was 138.5 cm. The values for plant height varied from 138.5 cm in the control variant to 159.20 cm in the variant with digestate. The variant and the YxV interaction had a statistically significant effect on plant height values. The year had no statistical significance for the investigated factor, tables 2 and 3, figure 2a.
The average value for the parameter - number of grains per panicle - was 48.50. The values of the number of grains per panicle varied from 44.33 in the control variant to 52.66 in the variant with digestate. The variant and the interaction of the examined factors VxY was statistically significant for the examined factor (tables 2 and 4, figure 2b). A more favorable year for the number of grains per panicle was 2022 compared to 2021. In 2022, the number of grains per panicle increased by 4.5%.
The average value for grain yield was 3.38 t ha-1 and varied from 3.011 ha-1 1 in the control variant to 3.75 t ha-1 in the variant with digestate. Year, variant and interaction of the examined factors were statistically significant for the examined factor (tables 2 and 5, figure 3a). A more favorable year for grain yield was 2022 compared to 2021. In 2022, a statistically significantly higher grain yield was achieved, by 340 kg ha-1, i.e. by 11.33% (tables 2 and 5).
The average value for protein content was 6.87% and varied from 6.45% in the control variant to 7.30% in the variant with digestate. The year, variant and interaction of the examined factors were statistically significant for the examined factor (table 2, figure 3b). The more favorable year for protein content was 2021 compared to 2022. In 2021, statistically significantly higher values were achieved for protein content, namely for 15, 85% (tables 2 and 6, figure 3b).
Jordanovska et al. (2018) points out that the protein content of oat grains varied from 12-15%, fat content from 4-6.5% and crude fiber content from 12.2-12.5%.
Correlation analysis of the studied oat traits
Correlation coefficients based on all tested traits during 2021-2022 had positive values (Table 7). Genotypic correlation coefficients provide a measure of the genetic association among characters and give an indication of characters that could be useful so as to identify more important ones for a particular selection programme. Correlation studies were conducted to study the degree of interrelationship between grain yield and their major traits.
Highly significant positive correlation coefficients were found between grain yield and number grains per plants (r=0.68··), grain yield and precipitaion (r=0.76·), grain yields and temperature (r=0.76·) and grain yield and planth height (r=0.59·). Significant positive correlations were found between number of grains in panicle and precipitation (r=0.66·) and planth height and temperature (r=0.59·).
Protein content did not have a significant correlation with grain yield (Table 7). A strong positive correlation between small yields and grain weight has been found by many researchers (Terzic et al., 2018), medium (Ðekić et al., 2012; 2014; 2018; Güngör et al., 2017), while weak positive dependence has been identified by Rajičić et al. (2020). Grain yield plant-1 exhibited significant and positive correlation coefficients with spike-lets panicle-1, 1000 seed weight (g) but negative non-significant correlation with protein content (Ahmad et al., 2013). These results will be beneficial in devising a selection scheme for identifying best genotypes possessing higher forage yield, grain yield and better quality.
CONCLUSIONS
Oat grain is used for nutrition as a grain but also for non-food products and due to its unique grain quality, it is known as a functional food. The results showed that year and digestate had statistically significant effect on oat grain yield. Statistically significantly higher grain yield values were achieved in the variant with digestate compared to the control variant, which is why its application in the oat crop is justified. Highly significant positive correlation coefficients were found between grain yield and number of grains per plants (r=0.68··), grain yield and precipitation (r=0.76·), grain yields and temperature (r=0.76·) and grain yield and plant height (r=0.59·).
Big progress has already been achieved in breeding oats. Breeders of oats need to make available to the market higher yielding and higher grain quality cultivars. Therefore, it is necessary to optimize the strategies of selection of superior oats genotypes.
ACKNOWLEDGEMENTS
This paper is part of the projects, Grant numbers: 451-03-47/2023-01/200116, 200032, 200042 and 2000357, financed by the Ministry of Science Technology Development and Innovations of the Republic of Serbia, and FAO Project "Redesigning the exploitation of small grains genetic resources towards increased sustainability of grain-value chain and improved farmers' livelihoods in Serbia and Bulgaria"-GRAINEFIT, 2020-2024, PR-166- Serbia;
Rakić, R, Ikanović, J., Popović, V., Rakić, S., Janković, S., Ristie, V., Petković, Z. (2023): Environment and digestate effect on the oats quality and yield parameters. Agriculture and Forestry, 69 (3): 247-257. doi: 10.17707/AgricultForest. 69.3.18
Notes: The authors declare that they have no conflicts of interest. Authorship Form signed online.
Recieved: 12/07/2023 Accepted:22/09/2023
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Abstract
In human nutrition, peeled oat grain is used in the form of oatmeal, semolina and oat flour, which is mixed with wheat to make bread and other bakery products (Figure la-c). The aim of this study was to investigate the effect of digestate on grain yield, productivity parameters and protein content of oat grain, over a two-year period. The sensors monitor the humidity of the oat grains, report to the central sensor that directly with the help of the aggregate automatically blows moist or dry air, depending on the need in order to maintain optimal conditions for storing oat seeds (Popovic et al., 2023). Correlation analysis of the studied oat traits Correlation coefficients based on all tested traits during 2021-2022 had positive values (Table 7).
You have requested "on-the-fly" machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Show full disclaimer
Neither ProQuest nor its licensors make any representations or warranties with respect to the translations. The translations are automatically generated "AS IS" and "AS AVAILABLE" and are not retained in our systems. PROQUEST AND ITS LICENSORS SPECIFICALLY DISCLAIM ANY AND ALL EXPRESS OR IMPLIED WARRANTIES, INCLUDING WITHOUT LIMITATION, ANY WARRANTIES FOR AVAILABILITY, ACCURACY, TIMELINESS, COMPLETENESS, NON-INFRINGMENT, MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Your use of the translations is subject to all use restrictions contained in your Electronic Products License Agreement and by using the translation functionality you agree to forgo any and all claims against ProQuest or its licensors for your use of the translation functionality and any output derived there from. Hide full disclaimer
Details
1 University of Belgrade, Faculty of Agriculture, Nemanjina 6, Belgrade 11000, REPUBLIC OF SERBIA
2 National Institute of the REPUBLIC OF SERBIA
3 Institute of Applied Science in Agriculture, Belgrade, REPUBLIC OF SERBIA