Structural Trend, Yield Shocks and Price: The Dynamics of Second-Crop Maize in Dourados, Mato Grosso Do Sul, Brazil, 1994–2025

The expansion of second-crop maize has reshaped the agricultural base of Dourados, one of the leading farming hubs in Mato Grosso do Sul, Brazil, yet little evidence exists on how output and price interact over a long horizon that includes the climate and market shocks of the 2020s. This study aimed to analyse the dynamic relationship between municipal maize output and the real price of the grain in the state from 1994 to 2025. It used 32 annual observations from the Municipal Agricultural Production survey of the Brazilian Institute of Geography and Statistics, deflated by the national consumer price index, and applied unit root tests with and without structural breaks, the autoregressive distributed lag bounds test, Toda-Yamamoto causality, the Nerlovian partial adjustment model and a variance decomposition of output growth. All series were stationary around a deterministic trend, with breaks in 2010–2011 for output, area and yield and in 2019 for price. Output grew tenfold, but about 62% of its annual variance stemmed from yield swings linked to drought and frost. No temporal precedence was found between output and price; harvested area responded to the previous year's price with a short-run elasticity of 0.20, and price reacted to state-wide supply shocks but not to Dourados output, which characterises the municipality as a price taker. Local farm income therefore depends more on managing weather and price risk than on productive responses to the market.