EFFECT OF FLUBENDIAMIDE AND SPIROTETRAMAT ON THE HAEMOCYTES OF AMERICAN BOLLWORM, HELICOVERPA ARMIGERA (LEPIDOPTERA: NOCTUIDAE)

The effect of flubendiamide and spirotetramat (LC_40 , LC_50 and LC_60 ) on total and differential haemocyte was evaluated on 3rd and 5th instar larvae of Helicoverpa armigera. The total haemocyte count at LC of flubendiamide increased just after application and became 50 (69300 cells/mm^3), decreased (52300 cells/mm^3) after half an hour, and increased again (68980 cells/mm^3) from normal (68175 cells/mm^3) after an hour The differential haemocyte . count, plasmatocytes decreased from normal 18% to 12%, whereas the percentage of prohaemocytes and, spherulocytes increased from normal (42%, 29% to 51%, 33%). The percentage of cystocytes and granulocytes decreased from normal (2.75% and 8.25% to 0%, 2%, respectively after the application of insecticide in 3rd instar larvae. Similar results were recorded with 5th instar larvae. The total haemocyte count just after the application of spirotetramat in 3rd instar larvae increased (78900 cells/mm^3) from the normal count, while decreased (64700 cells/mm^3) after half an hour, and increased again (80900 cells/mm^3) after one hour of application from the normal count (68175 cells/mm^3). The differential haemocyte count, plasmatocytes increased from normal 18% to 28%. The percentage of prohaemocytes and granulocytes decreased from normal (42% and 8.25% to 34% and 5.5% repectively), whereas percentage of cystocytes increased from normal (2.75% to 4%) after the application of insecticide in 3rd instar larvae. Similar results were recorded in 5th instar larvae of H. armigera.