Immunotoxic effects of force-fed ethephon on model organism Galleria mellonella (Lepidoptera: Pyralidae)

Abstract

Incorporation of chemical substances like plant growth regulators in agricultural practices to boost production has become inevitable; thus, they have accumulated in the environment in tremendous amounts. However, due to their nonselective nature, they affect several components of the ecosystem like the invertebrates. In this study, therefore, the effects of force-fed Ethephon on the cellular mediated immune system of model insect G. mellonella larvae were investigated using the lethal doses LD₂₅ and LD₅₀ determined in a previous study. Our results indicated that treating G. mellonella larvae with ETF significantly reduces the number of circulating hemocytes and also reduces the number of live cells while increasing the apoptotic and necrotic cell ratios at all doses. Additionally, ETF increased the number of spherulocytes, oenocytes and prohemocytes as well as the mitotic indices while reducing the number of granulocytes in circulation but did not alter the number of plasmatocytes. Moreover, the in vivo encapsulation assays showed significant suppression of the encapsulation abilities of the ETF treated G. mellonella larval hemocytes at both ETF doses. The findings of the current study are indicative of the ecotoxic effects that may arise due to ETF and that its usage should be controlled or monitored as it poses major threats to several organisms and the ecosystem at large.

Keywords:

• Ethephon
• Galleria mellonella
• insect immunity
• hemocytes
• plant growth regulators

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by Eskisehir Technical University, Scientific Research Projects Commission, of Turkey (Grant Number 20ADP211).