Diallyl Trisulfide, a Biologically Active Component of Garlic Essential Oil, Decreases Male Fertility in Sitotroga cerealella by Impairing Dimorphic Spermatogenesis, Sperm Motility and Lipid Homeostasis

Diallyl trisulfide (DAT) is a biologically active component of garlic essential oil and exhibits multi-targeted activity against many organisms. The current study tested the capacity of DAT to decrease the male fertility of Sitotroga cerealella. The effects on testis morphology, sperm number, motility, and lipid homeostasis were observed in adult males fumigated with DAT at a dose of 0.01 μL/L in air. The results indicated that the DAT significantly decreased the dimorphic sperm number. Meanwhile, the ultrastructural analysis of the sperm showed that the DAT caused malformed and aberrant structures of mitochondrial derivatives of dimorphic sperm. Additionally, the lipid homeostasis and ATP contents in the male adults were significantly decreased after treatment. Moreover, the total sperm motility was reduced, while the wave-propagation velocity, amplitude, frequency, and wavelength were significantly decreased compared with the controls. Overall, this study reported, for the first time, that DAT impairs energy metabolism, inhibits dimorphic spermatogenesis, and decreases sperm motility, while these abnormalities in sperm lead to adult-male infertility.