EMIGRATION ACITIVITY OF RICE WEEVIL Sitophilus oryzae L. (Coleoptera, Curculionidae) IN CONDITIONS OF REDUCED TEMPERATURE

The subject of the research was rice weevil Sitophilus oryzae L. - dangerous pest of grain crops storage. Research was held in a laboratory at the temperature 31 degrees C, optimal for this insect species, and reduced to 22 degrees C, and 70 +/- 5 % relative humidity (R. H.). The main research problem concerned the emigration activity of S. oryzae in conditions of temperature reduction. Population dynamics and sex structure of population were also analyzed. It was affirmed that rice weevil shows a very high emigration activity in temperatures both 31 degrees C and 22 degrees C. Whereas the temperature reduction to 22 degrees C causes drop of emigration activity to 40 % only in two time ranges after 60 and 120 days of raise ing. A higher female emigration was also observed.