LAUSR

BACKGROUND Peanuts are widely grown in Brazil due to their great importance in the domestic vegetable oil industry and the succession of sugarcane, soybean, and maize crops, contributing to soil conservation and improvement in agricultural areas. Thus, this study aimed to determine the zoning of peanuts' climatic risk by estimating the water requirement satisfaction index (WRSI) for the crop in Brazil. We used a historical series of data on average air temperature and rainfall between 1980 and 2016. Reference evapotranspiration (ETo) was estimated using the Thornthwaite (1948) method, subsequently calculated the crop evapotranspiration (ETc) and maximum evapotranspiration (ETm). Water balances for all stations were calculated using the Thornthwaite and Mather (1955) method, with available water capacity in the soil of 15 mm, 30 mm, and 45 mm. The definitions of suitable, unfit, and restricted areas and the planting season were performed using the water requirement satisfaction index (WRSI). RESULTS Brazil has low climatic risk areas for growing peanuts throughout the year, except for winter. The country shows 88.19%, 97.93%, 99.16%, and 39.25% of its suitable area for planting peanuts on planting dates in spring, summer, autumn, and winter, respectively. CONCLUSION Brazil has a large part of the areas favorable to the planting of peanuts. The maximum availability of soil water at a depth of 15, 30, and 45 mm does not influence regions for peanuts growing in Brazil. The states of Piauí, Ceará, and Bahia are the most unsuitable on the winter planting date, with an average WRSI of 0.22. This article is protected by copyright. All rights reserved.