Description of the Business As Usual (BAU):
Opposite to rotation, monoculture is performed in some agricultural systems, consisting in cultivate the same crop (or similar, e.g. wheat, barley) each season on the same plot. In addition, no till system is opposite to conventional tillage systems with crop residues removed.
Description of the system change:
Crop rotation is the sequence of different types of crops on the same plot. This produces diversity in root morphology and composition, improving soil biodiversity and microbiological activity. In annual crops, this practice is agronomically recommended because it breaks the cycle of pest, diseases and weeds reducing their adaptation.
Applicable to many regions in Europe, crop rotation with sunflower and cereal in the crop sequence is more common in Southern Europe, between 35-50° latitude. These crops are adapted to dry conditions common in the area. Although they could be also irrigated to increase productivity.
Crop rotations under No till requires the use of appropriate equipment and machinery. For No till sunflower sowing, it is essential to adjust the No till seeder for uniform emergence and optimal crop development. Monograin seeder is needed for sunflower to ensure accurate placement with a density of 50,000-80,000 seeds/ha. Seeding depth should be 3-5 cm, adjusting up to 6 cm in dry soils. To avoid sudden changes in the ground coverage for the next sowing, the harvest residues of the previous crop should be spread evenly. This is carried out with a residue spreading system and deflectors in the harvester. In this way, the No till seeder works better without a thicker or thinner layer of residue.
Weed control under No till is usually performed by herbicides under integrated weed management. Harvest residues from the previous crop help control weeds by restricting light and nutrients supply. Straw mulch cover prevents the soil-seed contact, hindering and reducing weed germination.