Estimativas da produtividade potencial e real da soja no médio-norte de Mato Grosso

Abstract

In agribusiness, a soybean crop is a major source of income, especially for a region in the north of the state of Mato Grosso, the country's largest producer. The objective of this study was to determine a potential and real productivity in the soybean crop of different productive cycles, with different sowing dates for the northern region of the state of Mato Grosso based on the version of the Agroecological Zone (ZAE). The study was developed based on a historical series of 15 years of data. The work was carried out with historical climatological data of an automatic and conventional meteorological station located in the municipality of Sinop (11.98 ° S, 55.56 ° W) referring to the monitoring network of the National Institute of Meteorology (INMET). The data obtained in the daily scale, in the platform BDMEP (Meteorological Database for Teaching and Research). The city is located in the northern region of the state of Mato Grosso, in the region of the Cerrado-Amazonian transition. Cultivars of five different development cycles, estimated by cumulative thermal sum (GDA) using the Ometto methodology (1981), were considered, and sowing occurred between a chronological date from October 1 and November 15, daily. The sequential water balance followed a methodology proposed by Thornthwaite and Mather (1955) and was performed on a daily basis. For an estimation of real and potential yields, it was used under the FAO Agroecological Zone model, described by Doorenbos and Kassam in 1979. A potential productivity of the crop presented a linear decreasing behavior, with a variability of 76 to 88 bags ha-1 in the difference Of production From October 1st to November 15th. On the other hand, the real productivity showed greater variations, evidencing an interference of availability in the last week. The model of the Agroecological Zone presented good results, regarding the estimated real productivity ratio and potential productivity for the different crop cycles. It is concluded that a time of direct sowing in soybean crop productivity, the model of the agroecological Zone and indicated for an estimation of the real soybean productivity in Sinop-MT, since they present coefficient of variation of 97% with when related A real productivity estimated by the model and experimental.