CS254253B1 - Method of increasing potato yield by fertilization according to chemical analysis of plants - Google Patents

Abstract

The solution concerns a method of increasing the yield and quality of potatoes. The purpose is to balance the ratio of nutrients in the potato crop for more efficient use of all nutrients taken up by plants. This is achieved by fertilizing the crop, in relation to the percentage content and ratio of basic nutrients in the phenophase of the beginning of flowering. This is a method that shows how to use a set of criteria and results of inorganic soil analysis to determine a possible nitrogen deficiency in plants (of the basic nutrients Ν, Ρ, Κ, which are lacking in plants) and to determine the dose of fertilizers needed to eliminate this deficiency. Compared to other methods, it has the advantage that it classifies the nutritional status of the crop, influenced by the quality of the seedling and the interaction of the weather with the agricultural technology used in a given year, and corrects it by fertilizing in the final phase of yield formation. In doing so, it prevents pre-fertilization of potatoes with nitrogen, thereby protecting their quality and contributing to environmental protection.

Description

The invention relates to a method of increasing the yield and/or quality of potatoes by the action of fertilizers added to the soil according to a chemical analysis of the plants.

Currently, nitrogen fertilization affects the yield and quality of potatoes according to flat-rate doses or local experience or visual assessment of plant appearance, which do not respect the biological requirements of plants according to the specific conditions of their nutritional status influenced by ecological conditions, including the quality of the seedling and the weather of the year and the level of agricultural technology affected by it. In practice, this leads to more frequent under-fertilization or over-fertilization, which not only wastes fertilizer, but also deteriorates the quality of potatoes and fails to achieve potentially high yields. This results in significant national economic losses caused by poor fertilizer use, as well as losses in yields and deterioration of potato quality and the efficiency of production of this important root crop.

These shortcomings are eliminated by the method of increasing potato yield by the action of fertilizers added to the soil according to the chemical analysis of plants, i.e. by fertilization according to the invention, the essence of which is that when the nitrogen content in the dry matter of the above-ground mass, i.e. in the phenophase of the beginning of flowering and/or at the beginning of bud shedding, is below 4.1% N and at an N/P ratio below 12.4 for varieties of the RADKA type, and 11.0 for varieties of the BLANÍK type and at a K/N ratio above 1.3, 10 to 80 kg.ha ¹ of nitrogen is added to the soil.

This means that such a crop and soil are treated with the specified dose of 10 to 80 kg.ha ¹ N differentiated according to potato varieties and useful directions, as indicated in tables A, B, in which the specific dose kg.ha ¹ N is determined by the position of the N/P ratio in the top between two extreme ratios (proportions). On the other hand, for crops with a K/N ratio = 1.3 and lower and/or with an N/P ratio above 10.9 in the top dry matter, nitrogen is added to all potato varieties only when the content is below 3.3% N in the top dry matter and the amount of its dose is limited to 40 kg.ha ¹ N, which are added to the soil when the content is below 2.7 i N in the top dry matter, up to 10 kg.ha ¹ N, which are added when the content is 3.2% N in the top dry matter.

The advantage is that the method according to the invention determines those potato crops that suffer from a lack of N and at the same time distinguishes them from crops with a good to excessive content of this nutrient, namely in the phase of the beginning of flowering. This means in the phase of a high need for nutrients for the formation of tubers and in the period until which the nutritional status of the crop could be significantly influenced not only by the composition of the soil and basic fertilization (forms, doses and method of application of individual types of fertilizers), but also by the size and quality of the seedlings used and the method of carrying out individual agrotechnical interventions and the weather, i.e. influences whose effect on the nutritional status of the crop could not be determined by the current methods of determining the need.

By eliminating the lump-sum addition of nitrogen (fertilization) in crops with a relative excess of nitrogen on the one hand and, conversely, by adding N to crops with a deficiency of this nutrient on the other hand, an increase in potato yield is obtained and their quality is improved, which suffers from lump-sum nitrogen fertilization in those areas that already had enough nitrogen or even a relative excess before this fertilization. This means that in the dry matter from the beginning of flowering they contained 4.1% N and more and/or due to a lack of phosphorus (i.e. due to a relative excess of nitrogen) they had a too high N/P ratio and/or similarly due to a lack of potassium they had a too low K/N ratio even with a content of 3.3 to 4.0 and N in the dry matter of the top. In all the cases mentioned here, there is a more efficient use of nutrients, as a result of adjusting their ratio in the plant and thus also protecting the environment.

According to the invention, (for crops with a physiological maturity assumption) in the above-mentioned phase, plant sampling and chemical analysis are carried out. Based on the chemical composition of the dry matter of the above-ground mass of the plants, the nutritional status of the crop is determined and fertilization measures are determined, which are carried out in the flowering phase, i.e. as soon as possible after the plant sampling. The determination of a specific dose of kg.ha ^-1 N fertilizers within the specified range is governed by the percentage of nitrogen in the dry matter of the top and, at a K/N ratio above 1.3, it is governed by the position of the determined N/P ratio between the two extreme ratios, as shown in the following tables A, B.

Table A:

Determination of the optimal dose of nitrogen for top dressing of potatoes of the RADKA type with a nitrogen content in the dry matter of the top at the beginning of flowering below 4.1% N, at a K/N ratio above 1.3

Ratio N rate in kg.ha for individual profitable potato directions N/A * seeds table or industrial consumable nat at the threshold value of the N/P criterion closer border lower upper lower upper lower upper under 5.0 60 70 80 . 5.0 to 7.9 60 50 70 60 ⁸⁰ 70 8.0 to 9.0 50 40 60 50 70 60 9.1 to 10.6 40 30 50 40 60 50 10.7 to 12.3 30 20 40 30 50 40 over 12.3 - - - - - -

Table B:

Determination of the optimal nitrogen dose in dry matter for fertilizing potatoes of the BLANÍK type with a nitrogen content in the early flowering phase below 4.1% N, at a K/N ratio above 1.3

Ratio N/P in dry matter Rate. N in kg.ha for individual potato production directions seeds desktop or industrial consumable nat at the cut-off value of the N/P criterion closer border lower upper lower upper lower upper

under 4.7 50 60 70 4.7 until 7.2 50 40 60 50 70 50 7.3 until 8.3 40 30 50 40 60 50 8.4 until 9.7 30 20 40 30 50 40 9.8 until 10.9 20 13 30 20 40 30 above 10, 9 - - - - - -

The following examples of the method of manure measures according to the invention are taken from field conditions and at the same time illustrate the results of tests of the subject of the invention. The implementation can be facilitated by classifying the given potato crop into one of the three groups (I, XI, III) listed below, according to its percentage content of basic nutrients (determined by chemical analysis of plant samples) in the dry matter of the crop and the ratios of these nutrients (N/P and K/N) calculated from it. These are the following groups (I, II, III):

1. Implementation of the method of fertilizer measures for stands with a nitrogen content in dry matter at the beginning of flowering and/or at the beginning of bud drop, below 4.1% N at a K/N ratio above 1.3.

With a nitrogen content below 4.1% N in the dry matter of the shoot and a K/N ratio above 1.3, the optimal nitrogen dose for individual types of varieties and potato uses is determined by the position of the determined N/P ratio in the dry matter of the shoot between the two extreme ratios listed in the table for the relevant type of variety (see Table A and Table Β), as shown in the following examples.

Example 1 (for table A)

The ratio N/P = 8.17 (with a content of 3.43% N, 0.42% P and 7.17% K, i.e. with a ratio K/N = 2.09) in the dry matter of the RADKA variety shows that a dose of 70 kg.ha of nitrogen should be added to such a crop of ware potatoes according to Table A.

Verification of this assumption showed that the basic yield of 26.73 t.ha of potatoes was increased to a yield of 31.95 t.ha”l by fertilizing such a crop with the specified dose of 70 kg.ha Ν'(8.VII.).

This means that for every kilogram of N (from the total applied dose of 70 kg.ha'*' N) there is an effective increase in yield of 74.6 kg of potatoes.

Example 2 (for table B)

The ratio N/P = 8.25 (with a content of 3.63% N, 0.44% P and 5.60% K, i.e.* with a K/N ratio ♦ 1.54) in the dry matter of the BLANÍK variety shows that, according to Table B, a dose of 40 kg.ha ¹ of nitrogen should be added to such a crop of industrial potatoes.

Verification of this assumption showed that fertilizing such a crop with a nitrogen dose of 40 kg.ha N (31.VII. in ammonium nitrate) increased the basic yield of 37.05 t.ha ^-1 potatoes to a yield of 42.30 t.ha . This means that for each kilogram of N (from the total dose of 40 kg.ha N) there is a highly effective increase in yield of 131.3 kg of potatoes.

II. Implementation of the method of fertilizer measures for stands with a K/N ratio of 1.3 or less and/or with an N/P ratio above 10.9, but with a nitrogen content in the dry matter of the shoot from the stage of the beginning of flowering and/or the beginning of bud fall below 3.3% N.

This method is used for all crops that contain less than 3.3% nitrogen in the dry matter of the shoot, without the optimal dose of nitrogen being determined from the above tables. Either because the ratio K/N = 1.3 or less was found in the dry matter of the shoot of the given crop and/or because the N/P ratio was found to be greater than the largest N/P ratio given in these tables (A,B) and/or because the given potato variety cannot be classified into any of the groups of varieties given in these tables. In all these cases, a crop with a nitrogen content in the dry matter of the shoot from the beginning of flowering below 3.3% N is added to at least a dose of nitrogen of up to 40 kg.ha N, regardless of the variety and the usefulness of the potato. It is useful, but in the case of a phosphorus deficiency and/or a potassium deficiency, it is necessary to use a smaller dose of nitrogen the higher the nitrogen content in the dry matter of the shoot. This means that at a nitrogen content of 2.6% N and less in the soil, a dose of 40 kg.ha N should be added; and similarly at a content of 2.7% N up to 35 kg N; at 2.8% N up to 30 kg N; at 2.9% up to 25 kg; at 3.0% up to 20 kg; at 3.1% up to 15 kg and at a content of 3.2% N, a dose of 10 kg.ha of nitrogen should be added. It is recommended to take into account that potassium deficiency depends on the nitrogen content in the plant and begins at a K/N ratio of 1.3 and less.

It is also recommended to take into account the differences between the genetically fixed properties of individual varieties. For example, the fact that the deficiency of the main nutrients begins in varieties of the BLANÍK type when their content is below 3.3% N and below 0.39% P. In contrast, in varieties of the RADKA type, the deficiency begins only when the nitrogen content is below 3.8% N, but already when the phosphorus content is below 0.36% P. The consequence of these genetically fixed differences in the properties of individual potato varieties is the differences in the limit values of the N/P ratio, as stated in the description of the subject of the invention. Overall, in the case of a lack of nitrogen, or possibly other nutrients in the rootstock, it is possible to proceed according to the following examples (which also provide an overview of the dependence of the size of the increase in potato yield, achieved with each kilogram of N from the dose of nitrogen added according to the invention, on the percentage content and ratio of nutrients in the rootstock and on the amount of the dose of nitrogen added):

Example 3 (for N/P ratio above 10.9 with severe nitrogen deficiency)

The nitrogen content of 2.55% N (with a content of 0.21% P and 5.08% K, i.e. with a K/N ratio = 1.99) in the dry matter of the tops of industrial potatoes of the BLANÍK variety shows the need to add 40 kg.ha of nitrogen, even though the N/P ratio = 12.14 (i.e. it is greater than the largest N/P ratio = 10.9, given in Table B).

Opening this assumption showed that the basic yield of 28.61 t.ha of potatoes was increased to a yield of 37.74 t.ha by fertilizing such a crop with a nitrogen dose of 40 kg.ha N. This means that for each kilogram of added nitrogen there is a highly effective increase (increase) in yield by 228.3 kg of potatoes.

Example 4 (for N/P ratio above 10.9 with medium N content and deep P deficiency)

The nitrogen content of 3.13% N (with a content of 0.19% P and 5.28% K, i.e. with a K/N ratio = 1.69) in the dry matter of the tops of ware potatoes of the RADKA variety shows the need to add a dose of 15 kg.ha of nitrogen, even though the N/P ratio = 16.47 (so it is significantly greater than the largest N/P ratio - 12.3, given in Table A).

Verification of this assumption showed that the basic yield of 31.10 t.ha ¹ of potatoes was increased to a yield of 32.73 t.ha by fertilizing such a crop with a dose of 40 kg.ha N (23.VII. in ammonium nitrate with limestone). This means that for each kilogram of added N there is an effective increase in yield of 40.8 kg of potatoes. However, the decreasing increase in tuber yield per 1 kg N indicates that the above-mentioned dose of 15 kg.ha N would be sufficient to fertilize such a crop, instead of the used dose of 40 kg.ha N.

Example 5 (for K/N and N/P ratios and N content close to limit values)

The K/N ratio = 1.21 (with a content of 3.76% N, 0.33% P and 4.56% K, i.e. with a N/P ratio = 11.39) in the dry matter of the RADKA variety indicates the need to reduce the nitrogen dose due to potassium deficiency even in the case that the N/P ratio = 11.39, i.e. that it is slightly smaller than the largest N/P ratio - 12.3, given in Table A. Also, the 3.76% N content in the dry matter of the RADKA variety is only slightly smaller than the 3.8% N content, which is, according to the invention, the limit value indicating the beginning of nitrogen deficiency in the growth of varieties of the RADKA type.

Verification of the above assumption showed that the basic yield of 38.75 t.ha of potatoes was increased to a yield of 42.90 t.ha by fertilizing such a crop with a nitrogen dose of 20 kg.ha ¹ N. This means that for every kilogram of the added dose of 20 kg.ha ¹ N, there is a highly effective increase in yield by 207.5 kg of potatoes. In contrast, fertilization with a higher dose of nitrogen of 40 kg.ha N in the same period (6.VIII.) already resulted in a decrease in yield to 39.75 t.ha of potatoes.

III. Implementation of the method of fertilizer measures for stands with a nitrogen content in the dry matter of the shoot in the phase of the beginning of flowering and/or at the beginning of bud drop above 4.0% N.

From the above description of the subject of the invention it follows that no nitrogen should be added to the RADKA type varieties and especially to the BLANÍK type varieties, when the nitrogen content in the dry matter of the top is above 4.0% N, even in those cases where the K/N ratio above 1.3 and/or the N/P ratio less than the N/P ratio = 12.3 (given in Table A) or even less than the N/P ratio = 10.9 (given in Table B) would allow it.

Verification of this assumption showed that with a content of 4.24% N, 0.56% P and 6.75% K in the dry matter of the RADKA variety, the achieved basic yield of 48.75 t.ha of potatoes was due to fertilization of such

-1 -1 growth rate with a dose of 40 kg.ha N (19.VII. in ammonium nitrate with limestone) reduced to a yield of 45.00 t.ha. This happened despite the fact that the nutrient ratio in the given case was N/P = 7.57 and K/N = 1.59.

The use of the subject of the invention in such cases, with a nitrogen content in the dry matter of the crop above 4.0% N, allows saving nitrogen fertilizers and preventing pollution of groundwater with nitrogen, which such crops cannot use. At the same time, both a reduction in potato yield and a deterioration in their quality resulting from over-fertilization of such crops with nitrogen are prevented.

The method of fertilization according to the invention allows to achieve higher yields of efficient potato varieties, to contribute to the improvement of their quality, to make better use of industrial fertilizers and to contribute to the protection of the environment. The detected deficiency of phosphorus or potassium in the soil also draws attention to the plots that need stock fertilization with the given nutrient (P or K) and thus contributes to the increase of soil fertility. In the examples of the method of fertilization measures according to the invention, the results of verification of these measures show their high profitability and provide the basis for assessing the expected profitability of similar measures even after possible changes in prices (potatoes, fertilizers, services) or wage relations.

Claims (1)

'OBJECT OF THE INVENTION Method for increasing the yield of potatoes by fertilization according to chemical analysis of plants, characterized in that at the nitrogen content in the dry matter of the above-ground mass at the beginning of flowering and / or fall the buds below 4.1% N and N / P ratio below 12.4 for RADKA varieties and 11.0 for varieties of the BLANlK type, and a K / N ratio above 1.3, 10 to 80 kg.ha / ^{1 of} nitrogen are added to the soil, with a content below 3.3% N in the dry matter and a K / N = 1.3 and less and / or at an N / P ratio above 10.9, nitrogen is added in all potato varieties at a dose of 40 kg.ha ^{- < 1 >} N.