Stage- and sex-dependent changes in the lipid profile of Dysdercus koenigii (Heteroptera: Pyrrhocoridae) during development

Abstract

Lipids were extracted from the plasma and gonads of fourth and fifth instars and adults of Dysdercus koenigii (Heteroptera: Pyrrhocoridae). Thin layer chromatography of the extracts revealed fractions of free fatty acids (FFA), monoglycerides (MG), diglycerides (DG), triglycerides (TG), phospholipids (PL), free cholesterol (FC) and esterified cholesterol (EC). There were distinct differences in the lipid profiles within sexes for both tissues during development. Phospholipid from female plasma showed significant fluctuation during development, while that from males remained constant. In female gonads, PL levels increased significantly from the fouth instar to the fifth instar. Monoglycerides were detected only in adult male plasma and adult female gonads, at very low levels. Plasma DG in males was found to increase significantly during development. Maximum gonadal DG was recorded in male fourth instars and female fifth instars. Triglycerides in female plasma declined from the fourth instar to the adult stage. In contrast, TG in gonads increased significantly in the fifth instar of both sexes. Plasma FFA of both sexes fluctuated during development. Free cholesterol was detected only in adult male plasma. Plasma EC increased from the fourth instar to the adult stage in males, and it was highest in gonads of fifth instars of both sexes.adultes. Le taux de EC du plasma augmente entre le quatrième stade juvénile et les adultes chez les mâles et il est plus élevé dans les gonades du cinquième stade juvénile chez les deux sexes.Mots clés: Dysdercus koenigii, développement, profil lipidique, TLC Abstract.

Biological and morphological parameters of Dysdercus maurus fed with low- or high-oil cotton seeds

“…This shows that variations in the duration of the second, third, and fifth instars of D. maurus are related to the oil content of the cotton seeds. In general, when seed-sucking cotton stainer nymphs store more lipids, they accumulate less water in their bodies, which may increase metabolic water production to compensate for water deficiency, affecting their development period (Mishra et al, 2004;Sláma & Lukáš, 2016). However, this depends on juvenile hormone production and total metabolic lipid combustion in the diet, as reported for Pyrrhocoris apterus L. (Jindra et al, 2013;Vinokurov et al, 2014;Sláma & Lukáš, 2016).…”