Table 1.

Phenotypes resulting from RNA interference‐mediated knockdown of putative Masculinizer (Masc) homologues. Hatch rates, pupal sex ratios and number of eggs exhibiting male‐isoform doublesex (dsx) splicing are shown of diamondback moth eggs following injection with double‐stranded RNA targeting either cytokinesis protein SepA‐like (SepA‐like; Plutella xylostella Masc), zinc finger CCCH domain‐containing protein 10‐like (CCCH) or an Anemonia majano Cyan (AmCyan) control. Hatch rates did not differ significantly between treatments (Χ ² = 2.90, df = 2, P = 0.24). However, the effect of treatment on pupal sex ratio was significant (Χ ² = 22.8, df = 2, P < 0.001) with SepA‐like being significantly different (a bias towards females) to both other treatments (P < 0.001), which themselves did not differ significantly (P > 0.05). A similar pattern was observed in dsx splicing in 48 h embryos with SepA‐like injected eggs showing a significant deviation from the AmCyan treatment (Χ ² = 16.25, df = 1, P < 0.001) representing a significant shift towards female‐isoform splicing. The AmCyan treatment itself did not significantly differ from the expected 50:50 ratio (Χ ² = 0.924, df = 1, P > 0.05)

	SepA‐like	CCCH	AmCyan
Eggs hatched	73/115	85/125	102/139
Number of pupae that were male	7/54	40/79	46/95
Number of eggs exhibiting male dsx splicing	1/39	NA	17/39