Toward the genetic suppression of Bactrocera dorsalis (Diptera:Tephritidae) through CRISPR/Cas9-mediated editing of spermatogenesis-related genes, Tssk1 and topi for imparting male sterility

Pest management based on CRISPR/Cas9-mediated site-specific mutations is an effective and environmentally safer strategy to suppress the pest population. However, the potential of this approach is yet to be tested on many important agricultural pests such as Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), a fit candidate for area-wide pest management. Therefore, in the present study, 2 spermatogenesis-related genes viz. Testis-specific zinc finger protein (topi) and Testis-specific serine protein kinase 1 (Tssk1) of B. dorsalis were edited to impart male sterility and its impact on further progeny. In this regard, topi and Tssk1 mutant populations deposited significantly fewer eggs per day (6.12 ± 0.36 and 3.60 ± 0.24, respectively) as compared to the control (11.16 ± 0.58 eggs per day). About the hatching rate, the above trend was observed, topi (44.51) and Tssk1 (30.04) as compared to the control (73.96). Furthermore, the total number of viable offspring for topi and Tssk1 populations decreased as a result of the cumulative progeny production ten days after the post-mating phase. It suggests that topi and Tssk1 from B. dorsalis could be potential targets for imparting male sterility in B. dorsalis.