Variation in production costs between 2000/01 and 2011/12 due to changes in management of soybean crops and grain production systems in Tucuman, Argentina

PEREZ, D.; DEVANI, M.R.; PAREDES, V.; RODRIGUEZ, G.; PLOPER, L.D.

Durban

Congreso; World Soybean Research Conference IX (WSRC IX); 2013

Protein Research Foundation

The province of Tucumán is located between 26º04’ and 28º06’ South latitude, and 64°28´ and 66º10’ West longitude, in the region known as northwestern Argentina (NWA). Commercial soybean production in this province dates back to the late 1960s. In the period 2000/01-2010/11, average yield reached 2.73 t/ha and both production and planted area grew at average annual rates of 8.35% and 3.54%, respectively. Soybean crop management in the region experienced significant changes. At present, over 99% of the cultivated area is under no-tillage system, planted with transgenic glyphosate-resistant cultivars with a yield potential, and mainly remains under soybean monocropping, with negative consequences. These practices changed the complex of pests, weeds, and diseases affecting the crop, and have prompted the use of more or different chemicals for their control, causing variations in production costs. The aim of this study was to analyze the variation in costs, gross margin, indifference yield, and average yield of soybean production in Tucuman, from 2001/01to 2011/12, while identifying sustainability issues. Production and marketing costs, gross margins and indifference yields for each growing season in the analyzed period were determined. The expenses scheme reflects the general situation of production in each season, and was based on public data plus inquiries to qualified informants. Expenditure on machinery and labor correspond to contractor values and taxes were not included. To determine gross product in each cycle, average soybean yield in Tucumán and average soybean price in the port of Rosario were considered. Between 2000/01 and 2011/12, costs incurred from planting to harvest grew at a 6% average annual rate. Planting, agrichemicals, transportation and administration costs increased at rates of 5%, 6%, 8%, and 10%, respectively. Fertilizer and insecticide applications and seed costs grew at rates of 9% and 5%, respectively. Expenditure on herbicides remained unchanged, considering the most common scenarios. However, in recent seasons glyphosate-tolerant and resistant weeds became more widespread, so weed control costs rose by 120%. Soybean domestic price increased at a 7.2% rate (being affected by government export taxes of 35%). Between 2000/01 and 2010/11 mean crop yield grew from 2.75 t/ha to 3.2 t/ha, at a 1.6% rate per year, but in 2011/12 it dropped to 1.23 t/ha, due to a severe drought. Throughout the period, indifference yields ranged between 1.1 and 1.4 t/ha on land tenure and between 1.5 and 2.1 t/ha on leased land. Soybean price and yield increases have allowed covering the higher production costs, except in the 2011/12 season. However, it is necessary to introduce product and crop rotation practices to improve soil carbon availability, physical and chemical fertility, and to reduce pest incidence and resistance development, which increase costs and reduce the sustainability of the system.