SU900185A1 - Soil phytotoxity determination method - Google Patents

Description

one

The invention relates to agriculture, namely to the determination of bio-diagnostics of soil fertility.

The definition of soil phytotoxicity is known by the method of agar plates with cellophane according to Krasilnikov 1.

There is also known a method for determining the phytotoxicity of a soil, including the manufacture of soil plates, followed by sowing seeds and measuring growth reactions 21.

The disadvantages of the known methods are insufficient access of oxygen to the seed pressed into the moistened plate, the overgrowth of the plate and seeds by mold fungi, direct contact of the seeds with pathogenic and conditionally pathogenic microorganisms, which significantly affects the results of soil phytotoxicity analysis.

The purpose of the invention is to improve the accuracy of determination.

The goal is achieved by over-wetting the soil plate, applying a layer of dry, sterile sand and incubating for 20-30 hours.

Example 1. Laboratory experience was established to determine the toxicity of chernozem of the soil (eaten under a sugar beet monoculture to millet. Soil samples were collected in the experimental

10 host institute.

To determine the toxicity of the soil, it is necessary to rewet the test sample to a creamy state and. distribute it in a bowl of Petri ki, to achieve an equal surface using a metal spatula. Then, a layer of dry, sterile sand, 0, + - 0.6 cm thick, preliminarily washed in water, is applied to the soil plate. A soil plate with sand is composted at room temperature to diffuse phytotoxins into sand. The humidity of the test sample of the soil with sand before sowing seeds should be balanced with aan within 70-80% of full capacity. Previously, for each type of tested soil, the full capacity is experimentally established and the required amount of water is calculated by calculation to bring the soil sample to full capacity. In all the test specimens, the weight of the soil in Petri dishes, as well as the layer of applied sand, should be the same. The weight of the soil and sand is established depending on the diameter and height of the Petri dish. Krom Petri dish experiments can be carried out in cuvettes to determine seed germination, used by seed control inspections, which need to be covered with glass on top. The control is a sterile peso moistened to 70-80 of full capacity. Sowing seeds is carried out in the sand by pressing them down to half their thickness. Grow seeds at. Accounting for sprouted seeds is kept on the third day. According to the seed germination rate under control

Table 1-4 and the sample to be tested judge the degree of soil toxicity. The results of the comparison of the known and proposed methods for determining the phytotoxicity of the soil are presented in Table 1. EXAMPLE 2: The results of the experiment to determine the toxicity of leached chernozem to sugar beets under seed shifts by hiring the crops are given in Table 2. The experiment was carried out according to the procedure described in Example 1. As can be seen from the table. 1 and 2, the proposed method is more precisely known due to the convergence of experimental variants and the control by physical indicators. An example of the calculation of soil toxicity. The seed of millet on control was 85% (85 seeds from SO), which is taken as 1001, and the germination rate on the experimental variant is x. control 85-100% experience 21 x 25%. Soil toxicity or percent inhibition of germination is 100-25 75.

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80 82 88 88

Average,% 85

Soil toxicity, 5j Note. HCP, „for experience 11.3%.

17 16 20 30

77 66 80 60

71 16

21 75

Seed germination,

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Average,% Toxicity,%

Note. NDS ,, „, for experience 3.9

Claims (2)

Claims A method for determining the phytotoxicity of a soil, including the manufacture of soil plates, followed by sowing seeds and measuring growth reactions, characterized in that, in order to improve the accuracy of determination, the soil plate is over-wetted, a layer of dry sterile sand is applied and maintained for 20 -30 h. table 2 60 5 58 56 57 26 Sources of information taken into account during the examination 1. Krasilnikov N.А. Methods for studying soil microorganisms and their metabolites. M, 1966, p. 171172. 2. Krasilnikov N.A. Methods for studying soil microorganisms and 35 of their metabolites. M ,, 1966, p. 171 (prototype).