Peanut Cultivation in Cordoba
Origin and Distribution
Peanut cultivation originated in southern Bolivia and the northern Argentine Republic. While ideal conditions exist in this region, 95% of production occurs in Cordoba due to its proximity to ports. Cordoba experienced peak peanut cultivation between 1997 and 1998, with 250,000 hectares, which later decreased to between 100,000 and 180,000 hectares. In the 2003 campaign, peanuts in Cordoba represented 6.85% of the southern region’s planted distribution and 4.87% of its production tonnage.
Peanut Life Cycle
Peanuts develop resistance in the soil through spore formation, their mode of reproduction. As heterotrophic fungi, they have a vegetative body and act as parasites, decomposing living material, or saprophytes, decomposing organic matter.
Soil Preparation
Soil Work
Soil work should focus on moisture retention, crust reduction, and the elimination of plow pans. Proper management of previous crop stubble is crucial, ensuring it is chopped and partially buried, or grazed fallow to allow water accumulation, facilitating rainfall infiltration and reducing evaporation.
Conventional Tillage
This method involves one or two plow passes followed by harrowing to create a suitable seedbed and control weeds. Herbicides can also be used for weed control, reducing the need for mechanical work.
Chisel Plowing
Chisel plowing replaces traditional plowing, minimizing soil erosion and leaving stubble on the surface. The goal is to achieve a seedbed with deep soil removal and semi-buried previous crop residue.
Soil Fertility
Peanuts rarely respond to direct fertilizer application except in extremely nutrient-poor soils.
Nitrogen
Peanuts struggle with nitrogen fixation. Artificial inoculation with Bradyrhizobium sp. is recommended in soils without a history of peanut crops. Factors like prolonged drought, crusting, or limited soil aeration can hinder nitrogen fixation. Nitrogen deficiency manifests as generalized yellowing (chlorosis), especially during reproductive stages.
Phosphorus
Phosphorus deficiency leads to slower growth, small dark leaves, and reddish stems and leaves in extreme cases.
Potassium
Excess phosphorus in the pod formation zone can create a nutritional imbalance, potentially causing pod rot.
Calcium and Other Cations
Peanuts are sensitive to calcium deficiency. Pods directly absorb calcium from the soil. Calcium deficiency can be addressed with soil amendments.
Magnesium
Magnesium deficiency appears as interveinal chlorosis, starting on older leaves and progressing to newer ones.
Sulfur
Sulfur is essential for new cell formation and chlorophyll development, influencing seed yield and quality. Sulfur deficiency restricts root growth and causes pale green leaves.
Iron
Iron deficiency is characterized by chlorophyll loss in younger leaves, resulting in pale green or yellow coloration. This restricts plant growth. Iron deficiency is common in calcareous, high-pH soils. Fertilizer treatment is less effective than applying iron chelates or foliar sprays of 3% ammonium ferrous sulfate.
Zinc
Zinc deficiency causes interveinal chlorosis in mature leaves. Zinc availability decreases with increasing soil pH. Zinc deficiency is rare.
Manganese
Manganese deficiency causes interveinal chlorosis in young leaves, particularly in high-pH soils. Foliar sprays are the most economical treatment.
Copper
Copper is required in minimal quantities. Deficiency is rare and typically occurs in organic soils.
Boron
Boron deficiency causes dark green leaves, restricted plant growth, and reduced seed quality. Roasted seeds may develop a brown discoloration called “hollow heart.” Boron deficiency is common in sandy, acidic, and heavily leached soils. Applying 0.5 kg/ha of boron can remedy this, but never exceed this dose.
Molybdenum
Molybdenum availability increases with pH, and the required amount is very low.
Peanut Cultivars
Two subspecies exist, each with two classes: Virginia (not currently grown in the country) and Runner (sown in 90% of the peanut area), and Spanish (sown in 10% of the area) and Valencia (less common).
Description of Cultivars: INTA Manfredi 68 Blanco (Spanish)
This cultivar has an upright, compact, well-branched, and regulated development. Strong pegs minimize pod loss during harvest. Medium-sized pods contain two medium to large grains. The pericarp has visible veins, preventing soil adhesion. Grains have a pale pink tegument. 100 grams weigh 42.43 grams, with a fat content of 45-47%. The planting-to-harvest period is 130-140 days, with a grain/harvest ratio of 66-73.