Technology of sunflower cultivation
On the fields loaded with long-term weeds (thistle, sow-thistle, lettuce, bindweed, etc.) is applied the level-by-level (improved) processing of the soil. At the beginning it is processed the stubble field on a depth of 6-8 cm with the disk tools, after the growth of the long-term weeds the soil is processed on a depth of 10-12 cm. After the repeated growth of the weeds, the autumn tilled field is plowed in September-October on the depth of 25-27 cm.
Soil processing before sowing
If we have a high-quality autumn tilling (friable and leveled soil, without proliferous weed roots), a single pre-sowing cultivation is usually used in the period of the mass growing of the weed sprouts and shoots.
The pre-sowing cultivation is performed on the depth of the sunflower crop sowing, namely at 6-8 cm, using for this purpose the cultivator of КПС-4 and КПШ-12 or УСМК-5,4 types, that are equipped with harrows and loops. In the case of the sunflower hybrids cultivation, which seeds are smaller than the grade seeds, the cultivation before the sowing is performed on a depth of 5-6 cm.
The fertilizers are applied in the autumn or spring under autumn plowing through locally band method simultaneously with the sowing of the sunflower. You should not use fertilizers, especially phosphorus, in spring by scattering under the pre-sowing cultivation, since it does not produce the desired effect. When locally-band method is applied the fertilizers is applied together with the sowing seeds by distributing them using mineral fertilizer device of the seeding machines at the distance of 6-10 cm and at a depth of 10-12 cm. If fertilizers were applied in autumn, then phosphorus fertilizer must be used in the rows while sowing (P10-15).
The modern grade and hybrid seeds of highly thin-skinned are distinguished by higher requirements for heat. They should be sown in a well-heated soil, when the temperature at the depth of the sowing (8-10 cm) reaches 10-12 ° C. In this case, the seeds germinate quickly and amiably, increasing their germination, which provides a more balanced development and maturation of the plants, and consequently, higher yields. In the case of early sowing these varieties of seeds do not germinate for a long time, and partly they lose their germination proprieties, which leads to the thinning of the crops. The sunflowers sowing in one field must be completed in 1-2 days.
Care of crops.
The sunflower harvesting performed by the combines should begin when the browning of the calathids reaches 85-90% (when the seed moisture is of 12-14%). The delay in harvesting with 5-6 days leads to a significant loss of seeds. The threshed seeds should be cleaned and dried. The seeds for storage should be cleaned seeds with a moisture content not exceeding 8%. Wet seeds quickly get warm, become rancid and lose their germination.