title: Effects of rearing density on larval growth and activity of digestive enzymes in Lymantria dispar L. (Lepidoptera: Lymantriidae).
abstract: Density dependent responses of 4th, 5th and 6th instar gypsy moth larvae were studied at the level of larval mass, midgut loading and activities of three digestive enzymes (alpha-amylase, trypsin and leucine aminopeptidase). High density significantly reduced larval mass while midgut loading (expressed as relative midgut mass) did not change except in the 5th instar where it was increased at high density. Specific amylase and leucine aminopeptidase activities were not affected by crowding. Specific trypsin activity was on average higher in crowded than in isolated larvae. High density also affected the correlations between midgut protein content and activities of two proteolytic enzymes suggesting differences in regulatory mechanisms of insect digestion. The importance of these changes for survival under stressful conditions is discussed.
authors.affiliation: Institute for Biological Research Sinisa Stanković, 11000 Belgrade, Serbia & Montenegro. jellaz@ibbi.ibiss.bg.ac.yu
authors.forename: Jelica
authors.initials: J
authors.lastname: Lazarević
authors.forename: Vesna
authors.initials: V
authors.lastname: Perić-Mataruga
authors.forename: Milena
authors.initials: M
authors.lastname: Vlahović
authors.forename: Marija
authors.initials: M
authors.lastname: Mrdaković
authors.forename: Dragan
authors.initials: D
authors.lastname: Cvetanović
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001835:Body Weight; D004063:Digestion / Q000502:physiology*; D004798:Enzymes / Q000378:metabolism*; D019476:Insect Proteins / Q000378:metabolism; D007814:Larva / Q000254:growth & development / Q000378:metabolism; D007931:Leucyl Aminopeptidase / Q000378:metabolism; D009036:Moths / Q000254:growth & development* / Q000378:metabolism*; D011156:Population Density; D014357:Trypsin / Q000378:metabolism; D015022:Yugoslavia; D000516:alpha-Amylases / Q000378:metabolism
chemical_list: D004798:Enzymes; D019476:Insect Proteins; D000516:alpha-Amylases; D007931:Leucyl Aminopeptidase; D014357:Trypsin