Effect of hexavalent chromium [Cr(VI)] on morphology and biochemical parameters of tasar silkworm (Antheraea mylitta D.)

Aim: The present study focused on investigation the harmful effects of Cr (VI) on the 5th instar larvae of Antheraea mylitta. Methodology: Silkworms were fed in an indoor setup with Arjuna (Terminalia arjuna) leaves treated with Cr (VI) at 10, 100 and 1000 ppm. The morphological study of larvae, along with biochemical assessments, was performed on larval and pupal haemolymph, as well as on silk gland and midgut tissues. Results: The findings revealed a concentration-dependent reduction in larval body length and weight over 10 days and an alteration in larval coloration. The inhibitory effect of Cr(VI) was more pronounced in males than females, with treated males exhibiting a 28% reduction in length and a 20% reduction in weight. Biochemical assessments on larval and pupal haemolymph, silk gland, and midgut indicated significant physiological stress and metabolic disruption due to Cr (VI) exposure. Interpretation: The findings suggest that chromium contamination affects the growth, development, and silk-producing potential of A. mylitta, with implications for the sustainability of the tasar silk industry. Key words: Antheraea mylitta, Chromium (VI), Tasar silkworm