Peculiarities of technique for growing corn
Choosing predecessor and crop rotation. Compared to other field crops corn is less demanding to predecessors. Winter crops, soybeans and other legumes, potatoes, vegetables are the most suitable for it. Spring cereals and sugar beets are satisfactory. Sunflower and perennial grasses are not suitable predecessors.
It is possible to place corn in one field for the second time, but not more than twice so far as a long-term monoculture leads to a significant accumulation of volatile smut infection, root and stem rot and enhances the number of corn borer and other pests.
Fertilization (during primary tillage – a complete fertilizer at the rate of N90-120P60-90K60-90 or manure within the norm 30-40 t / ha) – optimizes the supply of corn and increases its endurance to negative factors.
The main soil tillage (in autumn) is aimed at combating agricultural pests and creating further favorable conditions for plant growth:
- After early grain predecessors – stubble husking on 2 tracks, 2-3 weeks after massive regrowth of weeds – cultivation of the soil to a depth of 12-14 cm, and after the new regrowth of weeds – plowing to a depth of 25-30 cm;
- After predecessors, who later dismissed the field – stubble husking on two tracks later, with the advent of weeds shoots – plowing;
In the case of strong weed-infested fields with perennial dicotyledonous weeds and grass it is appropriate to use nonselective herbicides on the basis of solid salts of glyphosate. Mechanical soil tillage (repeat plowing or cultivation) is conducted only 2 (minimum) – 3 (optimum) weeks after introduction of the preparation.
- Leveling of the fields surface – early spring harrowing;
- One or two cultivations to a depth of 5-7 cm with the advent of weeds shoots;
- Introduction of ground (fixed) herbicides – preparations Prim Extra 720SC; Lyumaks 537,5 SE, Trophy 90ES, Harnes, etc.
Soil herbicides should be used if necessary.
The effectiveness of soil herbicides depends on soil moisture. If there is a moisture deficiency, the efficiency of the soil herbicides reduces, because their active ingredients are not received by the weed seedlings in sufficient quantity. If there are heavy rainfalls after application of preparations, soil herbicides may wash into the lower layers of the soil that reduces the effectiveness of their performance and increase the risk of intoxication crops.
- Start sowing – at a steady warming of the soil at a depth of seeding up to 10-12 ˚ C, usually in Forest-Steppe in third decade of April, in the Woodlands – 5-7 days before (sowing in cold soil results in intensive development of seeds mold, root and stem rot, increasing damage by soil pests; late sowing plants are more affected by smut diseases, damaged by Swedish flies, winter shovels);
- Depth of seeding is 5-6 cm, always in moist soil;
- Density of planting – depending on the hybrid’s group of ripeness and their cultivation zone (at the optimum planting density corn better suppresses the development of weeds in crops).
- soil rolling in order to enhance field germination of seed and reduce mold and root rot damage in conditions of high moisture;
- Adding soil herbicides recommended for inclusion after sowing culture Adenho 46,5% SC, к.с., Astrela Plus, с.е., Atsenit A 880 к.е.; Atsetohan 900 к.е.
- If the inspection of the corn leaves in the phases 3-5shows that the specific weight of weeds in the total mass of agrophytocenoses is less than 10%, they should be destroyed by the repeated cultivation of rows (first cultivation to a depth of 10-12 cm, in course of subsequent hoeing the depth should be gradually reduced to 5-6 cm to prevent injury to the root system of corn, besides the weeds, pupae grain beetles and winter shovels ova should be destroyed);
- If the inspection of the corn leaves in the phases 3-5shows that the specific weight of weeds in the total mass of agrophytocenoses is more than 10% – one should use post-germination herbicides according to the kind of weed, phase of growth of weed and cultivated plant and recommendations of the preparation’s producer (it should be indicated on the label).
- If soil herbicides were not applied or the effectiveness of their action was insufficient due to certain factors (weather conditions, low quality of farming operations, etc.), pre-germination herbicides can be used – Master 62% WG + BioPauer, Master Power, Titus Extra 75 + Trend 90 + pairs, Task 64 + PAR Trend, Basis 75 + PAR Trend, Titus 25 + Pairs Trend, Milagro 040 SC, Banvel 4S 480 SL.
Usage of this group of preparations can effectively kill both annual and perennial grasses and dicotyledonous weeds.
Removal of panicles.
- To destroy corn borer eggs – use Trichogramma: it is applied at the beginning of oviposition in 2 periods – 50 thousand copies. / 1 ha in 4-5 days 100-200 thousand ind. / 1 hectare, depending on the number of layings of pest eggs;
Harvesting – in brief period of time and at low cut off (8-12 cm) in order to reduce the number of corn borer caterpillars and reduce supply of Fusarium infection, nihrosporosis, Smut diseases and mold of seeds.
- Immediately after harvest – field disking with 2 traces for cutting post-harvest remnants;
- Autumn plowing that reduces the number of corn borer and the spread of diseases.