Productivity of Red Clover (Trifolium pratense L.) in Various Ways of Use in Soil and Climatic Conditions of the Western Region of Ukraine
(Running Text: Red Clover for Soil and Climatic Conditions)
Lesia Baystruk-Hlodan
Precarpathian Department of Scientific Research, Institute of Agriculture of Carpathian Region National Academy of Agrarian Sciences of Ukraine, Ukraine
Corresponding author E-mail: [email protected] Received: April 6, 2021 /Accepted: February 8, 2023
ABSTRACT
Red clover (Trifolium pratense L.) is a perennial plant of the legume family (Fabaceae). It is grown both in pure culture and in crops with perennial grasses. This study aims to assess the yield of red clover for hay (two cuttings) and pasture (four slopes) use in the soil and climatic conditions of the Western region of Ukraine. The subject of the study is four breeding numbers created by hybridization and selection methods.
The placement of variants is systematic in a sequential arrangement of repetitions in several tiers. Field experiments were carried out over three years (2018–2020) in competitive variety testing. The study found that, on average, the period from regrowth to slope ripeness lasted 67–95 days, from regrowth to pasture ripeness (30–61 days), and from regrowth to economic ripeness of seeds (136–172 days), depending on the years of cultivation. With the hay use of red clover, the yield is 41.14–44.78 t/ha, with the pasture 50.18–
52.38 t/ha.
Keywords: Harvest; Нay use; Пrazing use; Red clover; Ukraine INTRODUCTION
Trifolium pratense L. is the second-ranked fodder legume in the world after alfalfa (Medicago sativa L.) in the number of varieties created, produced, and sold seeds (Boller, Schubiger & Kölliker, 2010). Red clover was cultivated in the third century. However, it is also now used as a cover crop, as it inhibits weeds and improves soil fertility due to the ability of symbiotic bacteria to fix atmospheric nitrogen (McKenna, 2018). Although alfalfa feed contains more crude protein than red clover, its advantage is the presence of the enzyme polyphenol oxidase (PPO). This enzyme improves protein efficiency during ruminant digestion (Sullivan, Hatfield, 2006) and inhibits proteolysis during feed silage (Pahlow, 2003).
Pastures cover about 25% of the Earth's terrestrial ecosystems. In temperate zones, they provide most animal feed (Kingston-Smith, Marshall & Moorby, 2013), the main component of which is red clover (Phelan, Moloney, McGeough, Humphreys, Bertilsson, O'Riordan, & O'Kiely, 2015). It is easily cultivated on acidic and moist soils. Depending on the cultivation method, it can be grown in pure sowing and in a mixture of cereals and legumes. Clover has a high environmental value due to the ability to absorb atmospheric nitrogen, which reduces the use of nitrogen fertilizers (Thilakarathna, Papadopoulos, Rodd, et al. 2016; Eriksen, Askegaard, Rasmussen, Sоegaar, 2015; Jakešova, Repkova, Hampel, Čechova, Hofbauer, 2011; Krawutschke, Kleen, Weiher, Loges, Taube, Gierus, 2013).
Leto, Perčulija, Bošnjak, Kutnjak, Vranić, and Čačić (2013) studied the effect of inoculation of three varieties of red clover with two strains of Rhizobium leguminosarum bv. trifolii, and the effect of their cutting at two different stages of maturity on yield and chemical composition. According to the results of their research, the delay in harvesting red clover from early budding to early flowering increased the yield of two of the three varieties in the year of sowing and all three varieties in the last year of the study. There was an increase in the relative share of stems of total yield and a decrease in the relative share of leaves and flowers in all three years of research. Cutting red clover in the early budding stages resulted in 15.4 percent more crude protein content than at the beginning of flowering. At the same time, the differences in neutral and acid-washing fiber were insignificant. Varieties of red clover differed in all traits, while inoculation had no significant effect on any trait (Leto, Perčulija, Bošnjak, Kutnjak, Vranić, Čačić, 2013).
Researchers of Karbivska U. M. established the high efficiency of leguminous grasses on sod- podzolic surface gleyed soil (Karbivska, Turak, 2015). According to Riday (2010), the annual increase in the yield of red clover was similar to that obtained in alfalfa and other fodder legumes, according to a similar methodology. The yield of red clover varied from 0.21% to 1.39%.
The European feed sector faces new challenges. The European Union has introduced several guidelines for its member states to reduce environmental damage from agriculture (for example, the EU Directive on Nitrates for Drinking Water). These directives have limited the number of nutrients (especially nitrogen) used in meadows. As a result, fodder legumes, with their ability to symbiotic fixation of N2, play an increasing role in producing fodder for pastures in the dairy sector. Especially in northwestern Europe, red clover is gaining momentum for harvesting silage with corn (Gierus, Kleen, Loges, Taube, 2012;
Lüscher, Mueller-Harvey, Soussana, Rees & Peyraud, 2014 ).
This study aims to assess the yield of red clover for hay (two cuttings) and pasture (four slopes) use in the Western region of Ukraine.
MATERIALS AND METHODS
The studies were carried out in 2018-2020 on the experimental base of the Peredkarpatsky Department of Scientific Research of the Institute of Agriculture of the Carpathian Region of the NAAS (Ukraine) in competitive variety testing. The trial plot was adapted to the conditions at the planting site, with a plot size of 10 m2 and the accounting area for fodder (hay-making and pasture) productivity (2.5 m2).
Repetition three times. The Truskavchanka variety was taken as a standard. The placement of variants is systematic in a sequential arrangement of repeats in several tiers. Sowing of red clover was carried out manually with a seeding rate of 4500 pieces. They germinated seeds per 10 m2 in 201 –July 17, 2018–
August 15, 2019–August 8.
The soil of the field on which the research was conducted was drained by pottery drainage of soddy- middle-podzolic leaves, superficially gleyed middle-oxides, and loamy, formed on diluvial deposits. Weather conditions 2018–2020. They had several features. Significant differences from the long-term average data of the amount of precipitation and temperatures over the years of study were noted, which made it possible to more comprehensively assess the growth and development indicators of red clover during the growing season and the effect of environmental conditions on productivity (Fig. 1).
Fig. 1. Meteorogical conditions in 2018–2020
-10 -5 0 5 10 15 20 25
0 20 40 60 80 100 120 140 160 180
I II III IV V VI VIIVIII IX I II III IV V VI VIIVIII IX I II III IV V VI VIIVIII IX
2018 2019 2020
oC
mm
precipitation, mm
3
The material for the research was four breeding numbers: No. 1144 (hybrid population of the Precarpathian 6 x Skif 1); No. 1145 (hybrid population Predkarpatskaya 6 x CGP Violetta); No. 1146 (hybrid population Predkarpatskaya 6 x Kolubara) and No. 1147 (individual selection from the variety Hija 7417).
In the years of harvest accounting, the care of the crops consisted of feeding with mineral fertilizers, loosening the row spacings, and weeding from weeds by hand.
During the years of research, it was determined: (a) plant density [by counting the number of plants per 1 m2 (in two non-adjacent repetitions), followed by deducting the average]; (b) harvest structure (samples weighing 1 kg were taken before harvesting by cutting off bunches of plants with a sickle. They were immediately disassembled and counted, and the structural elements were weighed); (c) leafiness [L (%)] was determined according to the data of structural analysis (cuttings were attributed to the "leaves"
fraction) according to the formula 1:
L (%) = (Ml x 100) / Mr ...1) Where: Ml = leaf mass; Mr = the back of the growing line
(d) harvest accounting was carried out by mowing and weighing green mass from the entire counting area of the plot. Samples were taken for analysis. When determining the yield, the weight of all samples taken before mowing was considered. When using hay crops, the plants were mowed at the beginning of flowering (when the plots had 10% of the blooming heads). In total, two mows were carried out during the growing season.
With pasture (imitation of pasture), the plants were mowed during pasture ripeness (stalking phase, with a herbage height of 30 cm). In total, four mows were carried out during the growing season. The plot's dry matter yield was determined by a test sheaf's yield of green mass. A test sheaf was taken by weighing the green mass (weight 500 g) and dried under awnings in gauze bags to constant weight.
Phenological observations were carried out during the entire growing season according to the selection method of perennial grasses (Konik et al. 2015). The observation log noted the features of growth and development and plants' appearance. In the year of sowing, the following was recorded: the emergence of seedlings, mass seedlings, tillering, and the state before wintering. In the second year of life, the following was noted: the state after overwintering, the beginning and complete regrowth of green mass, stemming, budding, the onset of hay maturity, flowering, and the onset of economic ripeness of seeds. The later regrowth of red clover plants in 2018 can be explained by late spring and the onset of a warm period of +2.0 only at the end of March, as well as the return of spring frosts.
Spring 2020 started early. An increase in air temperature above 10°C occurred in the first or second decades of March, which resulted in the early restoration of the vegetation of clover plants after wintering.
The spring regrowth of red clover plants began on March 17 and fully regressed after seven days.
Regarding the temperature regime, March exceeded the long-term average by 3.1°С. The month of April was very warm. The air temperature on some days warmed up to +18 ... + 24 °С. The third decade of April was warm (10.6°С). By month, the temperature indicator exceeded the long-term average by only 1.0°С.
However, frosts were observed in May (-6°С), stopped the growth of meadow clover, and extended the interfacial period of "regrowth-stemming". As a result, the development phases of meadow clover shifted by about 14 days.
The experimental data were processed using analysis of variance using the Agrostat software and information complex, estimating the mean least squares and comparison using the probable difference in Fisher's F distribution (Dospekhov, 1985).
RESULTS AND DISCUSSIONS
In the Netherlands, red clover is used as a forage crop on dairy farms and sees its value and potential in symbiotic nitrogen fixation, productivity, and high protein content. One of the disadvantages that limit the use of such mixtures is the poor resistance of clover varieties, which are currently used by farmers (Van Eekeren, van Liere, de Vries, Rutgers, de Goede & Brussaard, 2009). The impact of poor-resistant varieties will be suppressed in unsuitable environmental conditions. Natural plant loss is characterized by clover, disease and pest damage, improper cultivation, freezing, and poor competitiveness are essential factors leading to poor resilience (Inostroza, Ortega-Klose, Vásquez, Wilckens, 2020).
Although feed production and disease resistance of wide varieties of red clover has improved significantly in recent decades, most varieties are still not resistant. In Switzerland, stable and adapted to the field crops of red clover, the so-called "mattenkli", show a high level of survival after three growing seasons in crops mixed with cereals (as opposed to traditional "akerli"). Clover is grown mainly in a mixture with grasses for some reasons, including the nutrient composition of feed and higher efficiency of nitrogen fixation (Nyfeler, Huguenin-Elie, Suter, Frossard & Lüscher 2011; Herbert, Ekschmitt, Wissemann, &
Becker, 2018), higher production, less soil contamination during harvest and a positive impact on soil quality (Annicchiarico & Pagnotta, 2012; Kleen, Taube & Gierus, 2011).
On the loamy soils of Belgium, varieties of red clover were studied in pure sowing and in a mixture.
The alfalfa and clover varieties tested in this experiment gave high yields of quality feed compared to nitrogen-fried fenugreek (Deprez, Lambert, Decamps, & Peeters, 2004). Clover is grown in Croatia's soil and climatic conditions for two to three years and is harvested three to five times a year. In pure crops, it yields up to 65 t/ha of green mass and 15 t/ha of dry matter (Popović, Tucak, Čupić, 2011; Tucak, Popović, Čupić, Krizmanić, Španić, Meglič, Radović, 2016 ).
In addition to the dependence of grass yield and quality of red clover on the genetic potential of varieties, these two traits are also influenced by biotic (pests, diseases), abiotic factors (pH, soil fertility, climatic conditions) and method of use (frequency and intensity of mowing or grazing) (Vaseva, Akiscan, Simova-Stoilova, Kostadinova, Nenkova, Anders, Feller, Demirevska, 2012; Kizekova, Tomaškin, Čunderlik, Jančova, Martincova, 2013; Harrison, Tardieu, Dong, Messina, Hammer, 2014; Shanker, Maheswari, Yadav, Desai, Bhanu, Attal, Venkateswarlu, 2014; Boelt, Julier, Karagić & Hampton 2015).
Numerous studies have shown that global climate change has led to a wide range of negative impacts on the yields of many field crops. According to Li, Chen, and Wu (2011), 25% of all agricultural land production in the world is underdeveloped due to droughts, limited growth, development, and productivity of many crops. Climate change (especially precipitation and temperature) has a direct, often adverse effect on the quality and yield of field crops.
According to Elgersma and Soegaard (2018), the relationship between quality parameters and weekly growth rate differed between species and functional groups in forage grasses. Results are discussed in the context of quantifying the impact of delaying the harvest date of grass–legume mixtures and the relationships between productivity and components of feed quality (Elgersma, Søegaard, 2018).
Therefore, studying the duration of mowing and seed maturity of red clover is important for crop planning and assessing the consequences for the fodder value of canned fodder in case of crop delay, as well as the creation of varieties of hay and pasture use. Spring regrowth of red clover plants was observed in 2018 (5.04), 2019 (21.03), and 2020 (27.03). On average, the amplitude of fluctuations in the duration of the regrowth-beginning of flowering of the first cut was 67–95 days. Slope ripeness of red clover (hay- making) occurred in 2018 (11.06), in 2019 (13.06), in 2020 (20.06) (Table 1). The plant density of meadow clover after overwintering in 2018 was 315–332 pcs, in 2019 was 339–345 pcs, in 2020 was 308–312 pcs.
Table 1. Dates of onset of slope and seed ripeness of numbers of red clover in competitive variety testing
Phase Years
2018 2019 2020
Regrowth 5.04 21.03 17.03
Grazing ripeness (grazing)1 05.05 07.05 21.05 Mowing ripeness (mowing)2 11.06 13.06 20.06 Economic ripeness of seeds 19.08 23.08 05.09 Remarks: 1 is the first grazing, 2 is the first mowing.
Plants in areas imitating pastures had the best foliage (60.3–72.8%). With the use of hay, this indicator was significantly lower and amounted to 33.1–42.5%. The leafiness decreases in clovers during the budding phase, during intensive stem growth. The data presented in Table 2 shows that with the hay- making method of use in terms of fodder productivity, the best numbers were 1146 and 1147, which provided a yield of green mass, respectively, 43.29 t/ha and 44.78 t/ha, dry matter, respectively, 10, 01 t/ha and 10.00 t/ha.
5
Table 2. Productivity of breeding numbers of red clover in competitive variety testing (2018–2020)
Cultivars Green mass Dry matter
t/hа ± to the St % to the St t/hа ± to the St % to the St Hay use
Truskavchanka - St 42.72 - 100 9.09 - 100
No. 1144 41.14 -1.58 96.3 9.45 +0.36 104.0
No. 1145 42.31 -0.41 99.0 9.05 -0.04 99.6
No. 1146 44.29 +1.57 103.6 10.01 +0.92 110.1
No. 1147 44.78 +2.06 104.8 10.00 +0.91 110.0
2018 1.16 0.52
2019 1.03 0.11
2020 1.10 1.21
Grazing use
Truskavchanka - St 50.29 - 100 9.89 - 100
No. 1144 50.68 +0.39 100.8 9.43 -0.46 95.3
No. 1145 50.18 -0.11 99.8 9.25 -0.64 93.5
No. 1146 51.68 +1.39 102.8 10.48 +0.59 105.9
No. 1147 52.38 +2.09 104.2 10.44 +0.55 105.6
2018 0.76 0.21
2019 0.95 0.15
2020 1.03 0.21
Remarks: Significant effects (p < .05) are shown in bold; St = standard?
With the pasture method of use in terms of fodder productivity, No. 1146 and No. 1147 significantly exceeded the standard for the yield of green mass by 1.39–2.09 t/ha and dry matter by 0 59–0.55 t/ha. The results of three years of research indicate that the multi-cut use of red clover significantly increases the quality of the vegetative mass since the protein content in the early mowing phases is much higher.
CONCLUSION
With the hay-making method of use (two mows), No. 1146 and No. 1147 were allocated, which provided a yield of green mass of 44.29 t/ha and 44.78 t/ha, dry matter, respectively, 10.01 t/ha and 10.00 t/ha. These numbers also stood out for pasture (four slopes) use, providing a yield of green mass, respectively, 51.68 t/ha and 52.38 t/ha; dry matter, respectively, 10.48 t/ha and 10.44 t/ha. The multi-cut use of red clover significantly increases the quality of the vegetative mass since the protein content in the early mowing phases is much higher.
ACKNOWLEDGEMENT
This study was carried out at the Institute of Agriculture of the Carpathian Region of the NAAS by order of the National Academy of Agrarian Sciences of Ukraine in accordance with the PND "Feed and fodder protein" (State registration number 0116U001322).
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