RU2806586C1 - Method for stimulation of growth and increasing immunity of tobacco plants to fungal pathogens - Google Patents

Abstract

FIELD: agriculture.

SUBSTANCE: invention can be used in the technology of tobacco cultivation. The method involves pre-sowing soaking of seeds and treatment of seedlings in the main phases of their formation with a "Grow-B" growth-stimulating plant protection agent with a fungicidal effect, the active substance of which is natural triterpene acids isolated from fir wood greenery. Soaking the seeds is carried out in an aqueous solution of the drug with a concentration of 0.10-0.05% for 3-12 hours, seedlings are treated in the main phases of its formation ("ears" and "seedlings suitable for planting") with an aqueous solution of the preparation in the same concentration using a watering can with the consumption of the working solution of 1 l / m². The sowing of seeds is carried out in a nutrient mixture with the content of the main nutrients N₃₅P₃₀K₃₅ that make up 50% of the optimally required dose.

EFFECT: method provides for increased germination and germination rate of seeds, increased yield of high-quality standard seedlings, stimulation of its immune potential, reduced damage by mycopathogenic infection, reduced forcing period, increased survival of plants in the field, increased yield and quality of tobacco raw materials while maintaining environmental ecology.

1 cl, 5 tbl

Description

The invention relates to the field of agriculture and can be used in growing tobacco as a growth-stimulating agent, as well as to increase the immunity of plants to mycopathogenic infections, increase the productivity of tobacco and improve the quality of tobacco raw materials.

High-quality tobacco seedlings are a success in obtaining a high yield of good quality tobacco raw materials. The main obstacle to obtaining standard seedlings is temperature changes in the spring and mycopathogenic organisms. To reduce these stress factors, it is advisable to use modern complex biostimulants that are capable of intensifying physiological and biochemical processes in plants, which promotes active plant growth and at the same time increases resistance to stress, including pathogens that cause diseases. And due to the fact that tobacco is a food crop with a significant amount of manual labor, it is important to use biologized preparations in the process of growing tobacco. The high physiological and fungicidal activity of modern biostimulants, including those based on triterpene acids obtained from fir greenery, manifests itself in low concentrations, which does not have a negative impact on the environment. Among the preparations made from fir greenery, growth regulators Silk and Verva have found wide use in agriculture.

There is a known method for stimulating the growth and development of oilseeds [RF patent No. 2121272, publ. 11/10/1998], where the Silk stimulant is recommended for the treatment of sunflower, cotton and rapeseed in doses of 1.0-10.0 g/ha. The method makes it possible to increase the oil content of sunflower seed kernels by 2.3%, cotton by 2.2% and rapeseed by 3.2%.

The use of growth regulators Verva based on triterpene acids obtained from fir woody greens was tested on table carrots and potatoes.

In a method for stimulating the growth and development of carrot plants [RF patent No. 2346421, publ. 02/20/2009, Bulletin. No. 5], seed treatment before sowing is carried out by soaking in an aqueous solution of the drug with a concentration of 0.2-2.0 ml/l for 24 hours two days before sowing and vegetative plants by spraying with the drug with a concentration of 20-40 ml/l in the phase of 3-4 true leaves and in the phase of the beginning of the formation of root crops at a consumption rate of 400 l/ha. This technique allows you to shorten the period of emergence and the growing season as a whole, increase the yield of carrots by 19.2%, and improve the quality of root crops by increasing sugars and carotene.

In a method for stimulating the growth and development of potatoes [RF patent No. 2425477, publ. 08/10/2011, Bulletin. No. 22] carry out pre-planting treatment of potato tubers and treatment of plants during the growing season. The biological product is used against the background of the calculated norm of mineral fertilizers. This method increases the productivity and quality of potatoes, while maintaining the effectiveness of protection against diseases.

As a prototype for the claimed method, a method was adopted for stimulating the growth and development of tobacco, as well as the immune potential of plants, which makes it possible to significantly reduce the frequency of treatment of crops with fungicides or completely abandon them [RF patent No. 2575105, publ. 08/14/2018, Bulletin. No. 23], including pre-sowing treatment of tobacco seeds in an aqueous solution of the plant growth regulator Verva, with a concentration of 0.01-0.05%. for 3 hours and spraying the plants in the “ears” and “seedlings ready for planting” phases with a solution in the same concentration of 0.01-0.05%.

The disadvantage of this method is the limited amount of the drug on the domestic market.

A new growth-stimulating plant protection product with a fungicidal effect “Grow-B” is known for treating seeds and leaves, the active substance of which is natural triterpene acids isolated from fir greenery. The biological product "Grow-B" contains active substances in the extract of at least 99.3%: natural triterpene acids (10 g/l), vitamins C, E, carotene, flavonoids, essential oils and trace elements. These components, except for triterpene acids (10 g/l), are not listed in the composition of the growth regulator "Verva". The drug enhances immunostimulating and growth-stimulating activity and has fungicidal properties. [Growth-stimulating plant protection product with a fungicidal effect “Grow-B” URL: https://spetshimagro.ru/our-products/prod fungicid/grow-b/].

The main objective of the proposed method is to adapt a new preparation based on triterpene acids isolated from fir greenery during tobacco cultivation.

The technical result of the invention is to increase the germination rate and rate of seed germination, obtain stronger seedlings, increase the yield of high-quality standard seedlings, stimulate their immune potential, reduce the damage to tobacco seedlings by mycopathogenic infection, reduce the period of their forcing, increase the survival rate of plants in the field, increase the yield and quality of tobacco raw materials against the background of preserving the ecology of the environment.

The technical result is achieved by the fact that in the method of stimulating the growth and increasing the immunity of tobacco plants to damage by fungal pathogens, including pre-sowing treatment of tobacco seeds by soaking and spraying the plants with a plant growth regulator in the main phases of its formation, “ears” and “seedlings suitable for planting”, according to of the invention, pre-sowing soaking of seeds and treatment of seedlings is carried out with a growth regulator Grow-B, the active ingredient of which is natural triterpene acids isolated from fir greenery, and soaking of seeds is carried out in an aqueous solution of the drug with a concentration of 0.10-0.05% for 3- 12 hours, seedlings are treated in the main phases of their formation in the same concentration, the volume of the working solution is 1 l/m, the seeds are sown in a nutrient mixture containing the main nutrients N ₃₅ P ₃₀ K ₃₅ , constituting 50% of the optimal required dose .

The method is carried out as follows.

In early spring, 2 weeks before sowing tobacco seeds, the nutrient mixture of the greenhouse is adjusted by adding mineral fertilizers to 50% of the supply of basic nutrients from the optimal required dose N ₃₅ P ₃₀ K ₃₅ according to agrotechnical analyzes of the substrate, or the nutrient mixture is replaced in accordance with the recommendations. To improve the sowing qualities of tobacco seeds, they are pre-soaked in concentrations of regulator solutions of 0.10-0.05% with an exposure time of 3-12 hours. The concentration ranges of the drug were taken for research according to the Methodological Guidelines for studying the effectiveness of the use of plant growth regulators in the germination of tobacco seeds (2013). Seed germination is carried out at a temperature of +27°C - +29°C for 3-4 days until 60% of the sprouts appear on them in the form of white dots. Sowing in greenhouses is carried out at the rate of 0.3 g/ ^m2 . The treatment of seedlings with the Grow-B regulator in the greenhouse is carried out in the “ears” and “seedlings suitable for planting” phase (before sampling) at a working solution consumption rate of 1 l/m (until the above-ground parts of the plants are completely wetted) in an effective concentration of the drug - 0.10 -0.05%. Tobacco seedlings are planted in the field at the optimal agrotechnical time, the plant density is 70x25 cm. The crop is harvested manually in sections (as the leaves ripen).

In the greenhouse farm of the institute and at the experimental selection site in 2020-2021. the method was tested to study the effect of the Grow-B stimulant on the growth and development of tobacco, reducing the damage to seedlings by fungal pathogens, root and stem rot, increasing the yield and quality of raw materials, and its results were analyzed.

It was established that the pre-sowing soaking of seeds in solutions with a concentration of 0.10% with an exposure of 12 hours and a concentration of 0.05% with an exposure of 3 and 6 hours and subsequent double spraying of tobacco seedlings in the main phases of seedling development “ears” and “ready for planting” "(before sampling) solutions of the drug at a concentration of 0.10% -0.05% made it possible to significantly increase the quality indicators of standard tobacco seedlings.

At the same time, the length of tobacco seedlings to the growth point when using a 0.10% aqueous solution of the Grow-B preparation for soaking seeds with an exposure of 12 hours and double treatment of plants increased by 24%, to the end of elongated leaves by 19%, the diameter of the stem at the root necks exceeded the control by 25%, the above-ground mass of “seedlings ready for planting” increased by 74%, and the mass of the root system by 58% (Table 1). The yield of standard tobacco seedlings was 970 pcs/m2 of greenhouse area, which exceeded the control by 23%.

When using a 0.05% solution for soaking seeds (exposure 3 hours) and twice foliar application, an increase in plant length from the root collar to the growth point was noted by 15%, to the end of elongated leaves by 17%, stem diameter by 20%, and an increase in wet weight stems and root system in comparison with the control by 57% and 53%, respectively. The yield of standard seedlings was 933 ^pcs./m2 , which was 18% higher than the control (791 ^pcs./m2 ).

Soaking the seeds in a 0.05% solution of the Grow-B regulator (6 hours) and spraying the plants with this preparation twice in the “ears” and “seedlings ready for planting” phase (before sampling) with the same concentration significantly increased the main quality criteria of standard seedlings: by 37%, 24%, 30%, 96%, 95% respectively. The yield of standard seedlings was 1020 ^pcs./m2 , which exceeded the control by 29%.

Due to the fact that the growth regulator Grow-B is declared by the manufacturer not only as a stimulant, but also as a fungicide, it is important to note that in the experimental plots with the tested drug no foci of damage to plants by seedling rot were recorded, whereas in the control variant 12% of plants were affected by stem rot.

Planting strong and developed tobacco plants in a field with a well-formed root system under the influence of the growth regulator Grow-B improves survival rate (96% of rooted experimental plants), compared to the control (82%).

Treatment of tobacco seeds and seedlings with the growth regulator Grow-B subsequently influenced the yield-forming parameter - plant height. Thus, the height of experimental plants in all experimental variants 30 days after planting tobacco in the field exceeded the control by 12-35%, during the intensive growth phase by 5-14%, and during the flowering period by 3-12% (Table 2).

Treatments also affected the length of the growing season. The total lifespan of tobacco plants during the field period is taken into account from the moment of planting and rooting of seedlings in the field (lasts 10-15 days) and until the ripening of the bolls on the inflorescence; it varies depending on the early maturity of the variety, climatic conditions, agricultural technology and can vary from 60 to 150 days. After rooting, a phase of intensive growth begins, which is characterized by the formation of new leaves and rapid growth of the stem; 40-50 days pass from the beginning of rooting to the budding phase (transition of the plant into the generative phase). 8-10 days after the bud appears, the first, central flower blooms - the flowering phase begins. The formation of a bud, flowers, and then bolls on a plant occurs due to the influx of reserve and synthesized nutrients from the vegetative organs of the plant - leaves and stems. The use of the Grow-B stimulator when soaking seeds and processing seedlings influenced the onset and duration of these important stages of development of tobacco plants. From the data presented in Table 3, it is clear that as of August 11, an average of 22 plants entered the budding phase in the control variant, while in the experimental variants, on average, the number of such plants was 9-11, which is half as much, this indicates that experimental plants continue to grow intensively.

When taking into account flowering plants on the same date, in the variant without the use of the Grow-B stimulator, it is clear that 11 plants have already bloomed, while in the variants with the use of the regulator, on average, 2-6 plants. By the end of the census in the flowering phase - September 2, 81% of the plants bloomed on the control, and 83-84% on the option using the Grow-B regulator. This indicates that plants, when treated with the Grow-B biostimulator, increase their vegetative mass over a longer period of time, as the growth of the stem and leaves on the plants continues, the number of ripe (technically mature) leaves increases, and this in turn has a positive effect on the increase in the main indicator field period - tobacco yields, while they bloom faster and form seed productivity.

Thus, the yield of tobacco plants under the influence of the growth regulator Grow-B increased compared to the control in almost all experimental variants, but its highest value was achieved in the variant when the seeds were soaked in a concentration of 0.05% for 6 hours and then the seedlings were sprayed twice in the main phases of development - 43.7 c/ha, which exceeded the control yield by 37% (Table 4).

Consequently, the number of leaves in the variants using the Grow-B preparation increased by 4-9 pieces, the leaf surface area exceeded the control by 17-28%.

The chemical composition of raw tobacco showed that the tested growth regulator significantly improves its quality. Thus, raw tobacco in options with soaking seeds and spraying tobacco seedlings in the main phases of “ears” and “seedlings suitable for planting” with Grow-B contains 56-68% more carbohydrates and 13-17% less proteins in compared with the control, which entailed an increase in the carbohydrate-protein ratio (the main indicator of the quality of tobacco raw materials) or the Schmuck number to a value of 1.34-1.43 (from 1 to 3 - the raw material is high quality) (Table 5).

The amount of nicotine compared to the control increased by 16-33%, which is considered a positive phenomenon when analyzing the quality of tobacco raw materials.

Claims (1)

A method for stimulating the growth and increasing the immunity of tobacco plants to damage by fungal pathogens includes treating seeds before sowing by soaking and vegetative plants in the main phases of development of “ears” and “seedlings suitable for planting” by spraying with a plant growth regulator, characterized in that pre-sowing soaking of seeds and seedlings are treated in the main phases of their formation with a growth-stimulating plant protection agent with a fungicidal effect "Grow-B", the active ingredient of which is natural triterpene acids isolated from fir greenery, and the seeds are soaked in an aqueous solution of the drug with a concentration of 0.10-0 .05% for 3-12 hours, treatment of seedlings in the “ears” and “seedlings suitable for planting” phases is carried out with an aqueous solution of the drug in the same concentration using a watering can in a volume of working solution - 1 l/m ² , sowing of seeds is carried out in nutrient mixture containing basic nutrients N ₃₅ P ₃₀ K ₃₅ , constituting 50% of the optimal required dose.