SOIL MOISTURE CONTENT AND SURFACE TEMPERATURE IN TILLAGE SYSTEMS AND STAGES OF DEVELOPMENT OF MAIZE CROP

摘要

abstract_textpThe tillage systems affect the amount of crop residue on the soil surface, and hence its temperature and moisture content. To evaluate the variation of moisture content and soil temperature in systems of tillage on maize growth stages, an experiment was conducted in Ultisol. The experiment was conducted with randomized complete block with four replications in Petrolina - PE, Brazil. The treatments consisted of five tillage systems applied to the plots - unprepared primary, off-set disc harrow of 0.56 m, off-set disc harrow of 0.61 m, chisel plow and moldboard plow. The soil moisture and temperature readings were taken at 6, 9, 12, 15 and 18 h for the different maize stages V3, V8, R3 and R6. Soil moisture was measured in the layer between 0.00-0.05 m by means of deformed samples by using gravimetric method and soil temperature at the surface with infrared thermometer. Systems of soil tillage and hours of reading influenced the moisture and soil temperature. The highest values of soil moisture content occur in the morning, while the highest temperature of the soil in the afternoon./p/abstract_text