Agrochemicals induced gene expression alterations in O. mossambicus

Abstract

The effect of agrochemicals in general and pesticides in particular on nontarget organisms has been a source of worldwide attention and concern for decades. Pesticide residues in water are a major concern as they pose a serious threat to biological communities including humans. The present study deals with the sub-lethal effect of four agrochemicals namely insecticide (Imidaclorprid-IMI), Herbicide (Pyraonsulfuron Ethyl-PE), Fungicide (Curzate-CZ) and plant nutrient (Mixture of Trace metal ions-MN) on the alteration in gene expression pattern of various target genes of hypothalamus pituitary gonadal axis (HPG) in Oreochromis mossambicus. IMI exposure resulted in an up regulation of the kisspeptin 2 and GnRH-I mRNA level in hypothalamic region, gonadotropin receptors (GtH-Ir and IIr) and estrogen receptor (ERI) in ovary. PE and CZ exposure altered the GtHIIr and Estrogen receptor II (ERII) mRNA levels in brain and ovary. Micronutrient mixture (MN) exposure altered the kiss 2 and ER-I transcript in hypothalamic region of brain and GtH-IIr and ER-I receptor in ovary. The result of the present study implies that agrochemicals has modified HPG axis which ultimately lead to the reduced reproductive fecundity of the fish.