The objective of this research was to characterize the influence of the meteorological elements in the head rice grains. Three irrigated rice cultivars were sowed at four distincts dates, during the recommended sowing period for the state of São Paulo. It was concluded that the percentage of head rice grains was more affected by the moisture content than by the harvesting time. The amplitude between minimum and maximum air relative humidity associated with the duration of the period in which air relative humidity was above 90% certainly was sufficient to cause fissures in grains with moisture content below 18%.
Oryza sativa; relative humidity; head grains; harvesting time