Effect of Rainfall and Technification on Arabica Coffee Productivity in Minas Gerais

Arabica coffee is the main agricultural product of the state of Minas Gerais and its production has great social and economic importance in the state. Several factors affect coffee productivity, such as climate, fertilization, soil, cultivars, management, disease incidence, and the presence of irrigation. More than 80% of the coffee crops in the state are rainfed, and are dependent on rainfall. The availability of water, especially during flowering and grain filling, is of great importance for productivity and the consequent economic return of the activities. Thus, the objective of this study was to evaluate the effect of rainfall from September to January on Arabica productivity in coffee-growing municipalities in Minas Gerais based on monthly accumulations limited to 210 mm. Municipal agricultural production data from IBGE from 2012 to 2019 for processed Arabica coffee and monthly rainfall data with 2.5 minutes spatial resolution, made available byWorldClim for the period 2010-2018, were used for this purpose. The ratio of productivity per accumulated rainfall was calculated for the coffee municipalities to determine the level of municipal technification and to filter out discrepant data. The municipalities were divided into technification groups and linear regression curves were determined for each group. For low and medium tech municipalities, a high correlation was obtained between rainfall from September to January, with monthly accumulations limited to 210 mm, and Arabica coffee productivity. In high tech municipalities, there was no significant correlation due to the presence of irrigation. The equations obtained showed the potential to estimate the effect of rainfall during the analyzed period on the productivity of municipalities in all regions of Minas Gerais and even productivity estimates based only on monthly rainfall.