CHANDRASHEKARA, K.ARAVINDA2018-04-262018-04-262017-07-30Th-11722http://krishikosh.egranth.ac.in/handle/1/5810044601A diverse array of resources is utilised by ants for their growth and survival. Ants are predatory, phytophagous, nectariorous, and grainivorous etc. Grainivorous ants are commonly called as “harvester ants”. The seed cleaning and other behaviours of harvester ant T. scabriceps was observed in the laboratory queen less ant nest (Formicarium). The results showed that, they perform self-grooming behaviour more frequently than antennation, followed by seed cleaning by mandibles, wall cleaning, allo-grooming, and abdominal wagging. The role of exocrine glandular secretion of these ants as seed protectant was also evaluated, the results suggest that these ants only mechanically clean the seeds in nest and they may not involve the use of any glandular secretion as antimicrobial seed protectants. Antimicrobial activity of 50 per cent acetonitrile:water extracts of head, thorax, and abdomen of T. Scabriceps was evaluated in vitro, against Gram-positive bacterium Escherichia coli and Gram-negative bacterium Staphylococcus aureus using “spot on lawn method” of bioassay. Among three body parts, head and thorax extracts does not shown any antimicrobial activity against both E. coli and S. aureus. Whereas abdomen extracts showed antimicrobial activity only against E. coli but not against S. aureus. Separation of antimicrobial peptide fractions of abdomen extracts was carried out using RP-HPLC. Among 14 fractions collected, only fraction-1 and fraction-2 showed in vitro antimicrobial activity in “spot on lawn method” bioassay. This study showed that T. scabriceps perform different behaviours in nest ant there may not be any association between antimicrobial peptides in the ants and seed cleaning behaviour.ennullThesis