Entomologia Croatica, Vol. 1 No. -, 1995.
Original scientific paper
CHANGES IN HAEMOCYTE COUNTS FOLLOWING TOPICAL APPLICATION OF β-ECDYSONE AND MAKISTERONE A ON 5ᵗʰ INSTAR NYMPHS OF Dysdercus cingulatus FABR. (HEMIPTERA, PYRRHOCORIDAE)
Ameena Ahmad
; Aligarh Muslim University, Aligarh, India
Abstract
Topical application of sub-lethal doses (0,5, 1, 2, 4 and 6 μg/nymph) of β-ecdysone and Makisterone A (a phytoecdysone) on 5ᵗʰ instar nymphs (24 h old) subsequently caused dose-based drop in total haemocyte counts, (THC). After 48 hours THC was only 25,5% and 31,4% with respect to 6 μg β-ecdysone and Makisterone A. But later in adults correspondingly there was appreciable increase in THC. However, in F₁ generation there was further reduction. The differential haemocyte counts were made on the basis of cells showing respective characteristics. Thus, in affected 5ᵗʰ instar nymphs (72 h old), effect was also dose-based. By the strongest dose of β-ecdysone, adipohaemocytes were completely destroyed and plasmatocytes were only 70% against control. Therefore, the percentage of prohaemocytes and oenocytoids which were less affected, were found highly increased. Similar nature of trend was observed with respect to Makisterone A. In emerged adults also there was selective damage on different haemocytes like that of nymphal stage. Although their distinguishing features were lost by the strongest dose. Both the hormones are toxic to the haemocytes but β-ecdysone proved more fatal than Makisterone A.
Keywords
Dysdercus cingulatus; β-ecdysone; haemocytes; Makisterone A; total haemocyte counts (THC); differential haemocyte counts (DHC)
Hrčak ID:
284266
URI
Publication date:
31.1.1996.
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