Productivity of binary vetch-and-grass mixtures in the conditions of a plain agricultural landscape of the western Ciscaucasia

. The purpose of this study is to establish the most suitable components in terms of productivity and quality for the effective cultivation of a binary vetch-and-grass mixture for the purpose of further harvesting haylage from it. The studies were carried out on winter crops: vetch + wheat and vetch + triticale; the soils are represented by leached, low-humus, powerful chernozems, located in the conditions of the alluvial-loess plain agricultural landscape of the Western Ciscaucasia (Krasnodar Territory) with plowed steppes. The subjects of the study were: Triticum aestivum L. variety of Tanya; Triticosecale Wittm. ex A. Camus variety of Khleborob; Vicia pannonica Granz varieties of Chernomorskaya and Orlan; Vicia vilossa op Roth varieties of Lugovskaya-2 and Glinkovskaya. Two cuttings were studied in different phenological phases. According to the results of the study, when mowing in the first ten days of May, the most productive grass mixtures are winter wheat of Tanya + Hungarian vetch of Orlan (green material – 102.6 c/ha, dry weight – 19.7 c/ha) and winter triticale of Khleborob + downy vetch of Glinkovskaya (100.2 c/ha of green material and 20.0 c/ha of dry mass). According to the results of laboratory studies, the most nutritious grass mixture was based on winter triticale and downy vetch.


Introduction
The share of sowing legume-grass mixtures in the western Ciscaucasia region should be increased to 50-55% of the total area sown with forage crops.Expanding the area under these crops will increase the yield and energy nutritional value of feed in animal diets [1][2][3].
New opportunities for increasing the volume and quality of forage supply for livestock farming in the western Ciscaucasia appear in connection with the cultivation of triticale.The green material of triticale is readily eaten by livestock; it is of great value for the preparation of haylage, grass meal, briquettes, pellets and silage.
Cultivation of mixed crops is an effective method of intensifying the production process and improving the quality of feed [4][5][6][7].
When forming mixed crops of annual and perennial crops, the complementarity of crops, seeding rates and ratios in mixtures must be taken into account.This makes it possible to achieve the normal development of the entire agrocenosis due to a more rational use of solar radiation by the components of the mixture and the absorption of nutrients from the soil.The correct selection of species for joint and mixed sowings is decisive.The environmental compatibility of the components included in the mixture is the main condition.This condition can be maintained by proper agricultural technology when cultivating mixtures and caring for the stem [8][9][10].
The winter grass mixture of triticale and vetch is ideal for southern Russia in terms of climatic conditions, since both crops are resistant to drought, which makes yield predictable, secondly, they quickly accumulate dry matter in the early phases of phenological development, and thirdly, they are responsive to improved nutrition and irrigation.And, importantly, the rate of dry matter increase in vetch exceeds the rate of lignification of crude fiber, and therefore the degree of accumulation of acid-detergent fiber (ADF) is also lower.It is important to sow tall triticale varieties with high foliage and a potential yield of 400 c/ha [11][12].
Also, vetch as a forage crop provides green fodder earlier than other crops.Therefore, the goal of our research was to develop the concept of a practically oriented technology for cultivating binary winter vetch-grass mixtures for the production of highquality haylage on chernozem, leached in the conditions of an alluvial-loess plain with plowed steppes in the agricultural landscape of the Western Ciscaucasia (Krasnodar Territory)

Material and methods
The objects of research: the factor of species and variety in the formation of the produc tivity of vetch-grass mixture.The subject of research: Triticum aestivum L. (winter wheat) variety of Tanya; Triticosecale Wittm.ex A.Camus (winter triticale) variety of Khleborob; Vicia pannonica Granz (Hungarian vetch) varieties of Chermonorskaya and Orlan; Vicia vilossa op Roth (downy vetch) varieties of Lugovskaya-2 and Glinkovskaya.
Weather conditions: 2019 corresponded to the long-term average, 2020 and 2021 were dry (77 and 74% of the long-term average precipitation with an average annual temperature of 0.7 and 0.9 °C above the long-term average).

Results
Productivity was determined in two periods -the 1st and 3rd ten days of May.When mowing in the first term, winter cereals (triticale and wheat plants) entered the heading phase, downy vetch plants just entered the budding phase, and Hungarian vetch plants completed this phase (Table 1 The analysis showed that the maximum yield of green mass (102.6 c/ha), as well as airdry (19.7 c/ha) and totally dry mass (17.9 c/ha) was formed on joint crops of wheat and Hungarian vetch of the Orlan variety.Reliably comparable to it, the yield of green (100.2 c/ha), dry (20.0 c/ha) and totally dry (18.1 c/ha) masses was formed when sowing winter triticale of the Khleborob variety together with winter downy vetch of the Glinkovskaya variety.The insignificant difference between these options is confirmed by statistical processing.LSD 05 (least significant difference) main effects for factor A for the "green mass" indicator -3.7 c/ha (2019), 3.2 c/ha (2020), 3.3 c/ha (2021).LSD 05 main effects for factor B for the "green mass" indicator -3.3 c/ha (2019), 3.0 c/ha (2020), 3.0 c/ha (2021).
At the second stage, according to productivity there are the following options: "Khleborob + Lugovskaya-2", "Tanya + Chernomorskaya", "Khleborob + Chernomorskaya", "Khleborob + Orlan" (the difference between them in this indicator is less than LSD 05 and therefore is not significant).At the last stage there are options: "Tanya + Lugovskaya-2" and "Tanya + Glinkovskaya".The general trend in the analysis of productive indicators during mowing in the second term was a greater increase in the vegetative mass of binary mixtures of cereals with winter downy vetch (with varieties of Lugovskaya 2 and Glinkovskaya) (Table 2).
According to the table, the most productive grass mixtures, with indicators of green (119.3 c/ha) and air-dry (21.8 c/ha) masses -are sown with triticale of the Khleborob variety together with downy vetch of the Glinkovskaya variety.Sowing winter wheat of Tanya variety together with the Orlan Hungarian vetch with indicators of green (105.4 c/ha) and air-dry (19.6 c/ha) masses are significantly inferior to the previous grass mixture.LSD 05 of partial differences in factor A for the "green mass" indicator is 5.At the next level in terms of productivity is the option "Khleborob + Lugovskaya-2" with indicators of green (91.2 c/ha) and air-dry (18.8 c/ha) masses.
In addition to gross harvests, the nutritional value of the resulting feed is very important (Table 3).The most nutritious of all grass mixtures harvested in the "end of shooting -beginning of flowering" phase (cutting -the first ten days of May) is Tanya winter wheat + Orlan Hungarian vetch (protein 2.6 c/ha, fiber 4.0 c/ha ), as well as winter triticale of Khleborob + Glinkovskaya downy vetch (protein 2.6 c/ha, fiber 3.9 c/ha).
Analysis of the nutritional value of feed during the second mowing period showed a similar picture ( For mowing in the third ten days of May, the following options are distinguished by the nutritional value of the grass mixture (in kg/ha): Khleborob triticale + Glinkovskaya downy vetch: protein 4.3, fiber 6.2, fat 1.3, ash 2.8; Khleborob triticale + Lugovskaya-2downy vetch: protein 4.0, fiber 5.3, fat 0.9, ash 1.8; Tanya winter wheat + Orlan Hungarian vetch: protein 3.7, fiber 5.1, fat 0.9, ash 1.6.

Discussions
Based on the positive effect established when mowing various grass mixtures, it was established that the maximum amount of nutrients in green fodder was obtained from a grass mixture of triticale and fluffy vetch (varieties Khleborob and Glinkovskaya), harvested in the third ten days of May (the flowering phase of both crops).The results obtained in our studies are consistent with previously conducted foreign studies [2,7].

Conclusions
In the conditions of the alluvial-loess plain with plowed steppes of the agricultural landscape of the Western Ciscaucasia (Krasnodar Territory), when mowing in the first ten days of May, the most productive grass mixtures of Tanya winter wheat + Orlan Hungarian vetch (green mass -102.6 c/ha, dry weight -19.7 c /ha) and Khleborob winter triticale + downy vetch Glinkovskaya (100.2 c/ha of green mass and 20.0 c/ha of dry mass).When mowing in the third ten days of May, the most productive grass mixtures are Khleborob winter triticale + downy vetch Glinkovskaya (119.3 c/ha of green and 21.8 c/ha of dry mass).The maximum amount of nutrients in green food was obtained from a grass mixture of triticale and downy vetch (varieties of Khleborob and Glinkovskaya), which was harvested in the third ten days of May (the flowering phase of both crops).

Table 2 .
Productivity of vetch-and-grass mixtures during mowing in the second term, 3rd decade of May (2019-2021).

Table 3 .
The amount of nutrients formed in the crops of vetch-and-grass mixtures by the mowing period in the first term, the 1st ten days of May (2019-2021).

Table 4 .
The amount of nutrients formed in the crops of vetch-cerea.