Early preparation of seed material for planting has a great influence on the growth and development of plants during the growing season, on their resistance to adverse external influences. Pre-sowing heating and germination of tubers accelerates the emergence of seedlings, promotes the rapid development and maturation of the crop. By the time of harvesting, such tubers have a ripe peel, which significantly reduces their injury.
The pre-planting preparation of tubers includes a bulkhead, various methods of heating and germination, stimulating treatments and pickling with pesticides.
If tubers were not calibrated after harvesting the potatoes in the fall, then this is done before planting. From the total mass of potatoes, diseased and clearly non-standard (small change up to 25 g and large - over 80 g) tubers should be removed. When calibrating, the tubers must be divided into fractions of 30-50 g, 50-80 g. Each fraction must be planted separately. This will allow you to correctly calculate the planting density, to ensure the uniformity of seedlings.
Air heating dramatically increases the yield of potatoes. Germination, or vernalization, of tubers provides fast and uniform shoots, increases the number of stems, accelerates the growth and development of plants. This technique is of particular value when growing commercial and seed potatoes.
On warm days, the tubers are removed from the store or the temperature in it is raised. If the tubers are without sprouts, the temperature from + 2-4 ° C is increased to + 15-20 ° C. As soon as their awakening begins, the temperature is reduced to + 10-6 ° C and the lighting is turned on to have short and strong shoots.
Often tubers sprout single filamentous sprouts, which is very undesirable. In such cases, to increase the number of sprouted germs, single germs are removed. If numerous short sprouts appeared on the tubers, such tubers are prepared for planting.
If planting is delayed due to weather, the storage temperature is reduced. After warming up, the seed is sorted out, removing the affected tubers. Heating stimulates the manifestation of latent infection, diseases and promotes the selection of healthy tubers.
Germination can also be carried out in shallow boxes, mesh and plastic bags (135 x 28 cm in size, in which holes are made along the length), in bulk under a film, or in greenhouses. At the same time, the main conditions must be observed: the embankment must be low, and the light must be diffused, when germinating in room conditions at a temperature of + 15-20 ° C, the tubers must be periodically moistened.
It is also very important to periodically turn them over so that all sprouted sprouts grow stronger and green in the light. Diffused light can be obtained by covering boxes, packages or a mound with any light or white cloth or paper. When placing tubers in areas protected from direct sunlight, no cover is required. Moistening of tubers is carried out after 5-6 days, spraying them with water or a weak solution of pink potassium permanganate.
It happens that with prolonged storage and high temperature, the tubers lose turgor and form long shoots. In such cases, breaking off the sprouts is not recommended, it is better to try to withstand the tubers for 7-10 days at a low temperature.
At food plantings, seed potatoes can be cut, which allows the use of large tubers and reduce the consumption of seed material. For cutting, the tubers are first germinated in order to have 2-3 sprouts on each tuber piece and thereby reduce the sprouting of seedlings. The mass of the piece should be at least 25-30 g.
After cutting the seed tubers create conditions to stimulate the formation of a protective suberin layer on the cut surface (increased air humidity at 15 ° C and its active circulation). Cutting times depend on soil conditions. If conditions are favorable (soil is moist, temperature 10-18 ° C), cut before planting. The healing of the cut surface occurs in the soil. If the soil is dry or too damp and the temperature is high or low, cut 5-8 days before planting.
To increase the resistance of plants to late blight during the germination period, it is advisable to treat the tubers twice with a 0,02% solution of copper sulfate: the first time - 7-10 days after the start of germination, the second - 7 days before planting.
A good result in the fight against infection is given by a combination of germination with pre-seed powdering of seed tubers with wood ash, which contains many trace elements necessary for the growth and development of plants. Dusting with ash at the rate of 1 kg of ash per 50 kg of planting material increases the yield, starch content and improves the taste of potatoes.
In the absence of ash, tubers can be sprayed with a mixture of trace elements (2 g of copper sulfate and 10 g of potassium permanganate per 10 l of water) or copper sulfate (2 g per 10 l of water) and boric acid (up to 10 g per 10 l of water) before planting. For 100 kg of tubers spend 2 l of solution.
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