CARACTERÍSTICAS HIDROCLIMÁTICAS PARA A CULTURA DO MILHO EM GUARAPUAVA-PR

Abstract

The maize is one of the main crops cultivated in Paraná State in cultivated area and volume of production. However, frequently the production is lost because of the problems happened by the stress of the soil water deficit and because of the irregular distribution of the rainfall. The main objective of this work was to measure the behavior of the water over the corn crop and how to establish the best days of sowing to minimize the chances of soil water deficit and its effects on the production of the crop in the region of Guarapuava. The study was developed on the campus CEDETEG in University Estadual do Centro Oeste – UNICENTRO having base on the historic sequence of the climatic data on the period of 1984 to 2008 which were compiled on the collection of agrometereological station of the University located on the Latitude 25° 23’02’’, Longitude 51° 29’43’’ W in 1026 meters of altitude. The duration of the crop cycle was calculated on the accumulation of maximum plant height and available water between the water balance of the crop onsiderating the distribution of the rainfall and the evapotranspiration of the crop. The chances of reduction the grain production were established trough the determination of the maximum of the evapotranspiration combined with the pre defined index of the answer of the crop on the soil water deficit. It showed that the corn crop is affected by the distribution of available water as long as the cycle and the phenological state and the chances of the submission on soil water deficit is A-F(R1) (anthesis-fecundation); the later sowing is the recommended period to cause the reduction of the chances of grain production below the average interval. The date of November, 10th showed to be indicated to the corn sowing in the region to obtain the biggest probability to get the grain production in or over the average interval, associate with one of the smallest chances to produce beneath the interval and one of the smallest indexes to happen the soil water deficit on A-F (R1) state.