OF THE EXPERIMENT ON SCARIFICATION OF SEEDS OF FORAGE LEGUME

If the hard seed (seed that is viable but has an impervious seed coat) content of legumes is greater than 20%, scarification should be considered. Scarification is the nicking of the seed coat to allow moisture to penetrate [1]. This type of seed treatment before sowing is of great importance, as it increases the yield of fodder plants by reducing the sowing rate of rare and expensive fodder seeds, reducing the cost of sowing, accelerating germination, and increasing the percentage of germination. This article reflects the results of a planned experiment to determine the effectiveness of scarification of a device for impacting alfalfa seeds, depending on factors such as seed impact speed, impact angle, and impact surface grit, presented a mathematical model of the relationship between these factors and determined their optimal values.


Introduction.
Determination of the percentage of hard seeds in the seeds of leguminous fodder plants is essential for seed preparation for sowing. This is due to the fact that the hard shell of legume grass seeds does not allow air and moisture to pass through, because of this, these seeds do not swell and do not produce a crop. Therefore, it is necessary to create conditions for the penetration of air and moisture by scarifying the hard shell of hard seeds. According to research conducted in Russia, depending on the climatic conditions of the year of seed collection, the chemical composition of the soil, and the type of plant, about 30-70% of the seeds of legume fodder plants have a hard shell. Based on this, if the percentage of seeds with a hard shell in the seeds of fodder legumes can be reduced, then the cost of cultivation will be reduced and the efficiency of fodder plant cultivation will be improved.

RS Global
Scarification is an operation in which the hard waterproof shell of the seed is slightly peeled off in order to speed up and facilitate the swelling and germination of the seed.
Seed scarification involves weakening the coating of the seed to encourage sprouting. This can be done in a number of ways, but the most common is mechanically breaking a seed's shell.
There are several ways to scarify seeds before sowing (Fig. 1).

Figure 1. Classification of the main methods of scarification of seeds for sowing.
The simplest and most widely used method in industrial conditions is the method of mechanical action on the hard seed shell. Mechanical scarifiers according to technological characteristics are divided into friction, impact, and needles. There are disks, drums, needles, and pneumatic scarifiers.

Experimental design.
It was assumed that alfalfa seeds thrown and accelerated by a strong air flow with a light touch on the abrasive surface lose the tightness of the hard shell and a three-factor randomized experiment was carried out to determine the rate of scarification. The rate of scarification (C) was determined depending on three factors, such as the speed of movement of the seed (v), the angle of the velocity vector to the working surface along the normal to the impact (β), and the abrasive surface grit (z). The test black box is shown below (Fig. 2).  3the abrasive surface grit -, [μm]; Controllable but unmanaged factors: w1crop seed moisture; w2the movement of crop seed around its own axis; w3temperature of crop seeds; Unmanaged factors: 1ambient air temperature, 2ambient air humidity. The experimental plan consists of a three-factored (n = 3) factorial design with five levels. Levels of variation and codes of the independent variables of x1, x2, and x3 for the rate of scarification are presented in Table 1.  0  25  60  40  90  16  0  0  0  25  60  40  80  17  0  0  0  25  60  40  70  18  0  0  0  25  60  40  70  19  0  0  0  25  60  40  70  20  0  0  0  25  60  40  90 Optimization parameters: -Rate of Scarification, C, (C→100%); The Rate of Scarification: Of this: 1 − number of seeds with a hard shell before processing, pieces; 2 − number of seeds with a hard shell after processing, pieces. Grain materials and equipment used for the experiment: • Alfalfa seeds sort: Burgaltai. Testing instruments. The seed throwing test equipment has a gas injection compressor, a gas collection pipe, a pressure gauge and a working surface capable of changing the impact angle (Fig. 3).  Figure 4, and seed germination was determined using a digital microscope.

Results.
Before the experiment, when determining the number of seeds with a hard shell according to the GOST 12039-82 method [2], it was 45%.
Non-germinated seeds were considered hard-shelled seeds. Figure 5 shows the difference between germinated seeds and hard-shelled seeds.   Table 4. Results of analysis of curvilinear regression equation between the rate of scarification (y) and speed of seed (x1), impact angle (x2), and grit of abrasive surface (x3  The analysis of variance (ANOVA) after deleting the non-significant terms is given in Table  3. The determination coefficient (R 2 = 0.71) indicates that a variance of only 29% is not explained by the model. Table 4) is less than 0.05 which indicates that the model is significant.  Conclusion.

1.
Нas have been created а mathematical model (2) of the process of wiping and scarifying alfalfa seeds by impact.

2.
In this experiment, the optimal values of the scarification rate of alfalfa seeds is 81.65%.