Analytical models of population growth were developed for Sitophilus zeamais, in grain wheat stored at 11.1% of moisture content. Population growth was monitored for 90 days at the temperatures of 16, 20, 24, 28, 32 and 36 ºC and initial adult population densities varying between 1.3 and 9.3 insects per kg. The models obtained explained between 93.9 and 98.99% of the variation in density of adult insects. The population growth was affected by initial population density of infestation and increased proportionately with degree of infestation. The highest population growth occurred at 28 ºC and drastically decreased for lower and higher temperatures. Population extinction took place between 15 and 45 days of storage for all samples maintained at 36 ºC, but no extinction was observed at 16 ºC. The models obtained present excellent adjustments and are in agreement with general principles underlying the pest-storage system; they reproduce very well the general effect of temperature and initial population densities upon S. zeamais population growth.
grains; insects; infestation; temperature
