Abstract: Artificial administration of gradient NaF solution to the fourth or fifth instar larvae of Bombyx mori larvae for 48 or 96 hours shows that NaF administration to the fourth instar for 48 hours has no negative effect on the fecundity of B. mori if the female larvae has normal pupation, eclOSion and egg laying, but the number of formed and laid eggs, percentage of laid eggs and hatchability are significantly decreased when 11igh concentration of fluoride is fed to the fifth instar larvae. However, low concentration of fluoride has a poSitive effect on the fecundity of the highly fluoride resistant variety -Zhenong 1. The ingested fluoride mainly distributed in midgut tissues and Malpighian tubules is not transferred to the eggs.

Key words: Bombyx mori, Fluoride pollution, Fecundity, ecosystem function, allochthonous material, land-water interaction, biodiversity, community structure