Fundamentals and applications of PlanejArroz, a software for irrigated rice management and yield estimation

Despite being relatively high (7.7 t ha -1 ), the average yield of irrigated rice in the State of Rio Grande Sul (RS) can be even higher, if the management practices are carried out at the most appropriate time, considering the date of occurrence of the main stages of plant development (PDS). The objective of this article was to demonstrate the fundamentals and applications of the software PlanejArroz to estimate the date of occurrence of six PDS, aiming the crop management, and the expected grain yield. Based on the degree-day method, the software estimates the date of each of the six PDS, using historical series (30 years) of climatic data, and updates these estimates using the current season’s meteorological data. This information can be generated for 131 rice producing municipalities and for 41 cultivars recommended for cultivation in RS. Likewise, grain yield, for the three most sown cultivars, can be estimated as an average of 30 years and for the current cropping season. The PlanejArroz is a tool that allows management practices to be carried out at the most appropriate time, estimating the date of the occurrence of six PDS associated with these practices. It is also possible to simulate the most appropriate sowing dates and to obtain the expected average grain yield for the current season.