Which observation indicates phytotoxicity in treated seeds during verification?

• A. Increased germination rate.
• B. Reduced germination or abnormal seedling growth.
• C. Seed color change is the sole indicator.
• D. No difference from untreated.

Answer: (B)

Phytotoxicity occurs when a seed treatment harms the plant tissues, showing up as problems with germination and how the seedling develops. In verifying treated seeds, you’re looking for signs that the chemical is affecting the seed’s ability to sprout or grow normally. The best indicator is reduced germination or abnormal seedling growth because this directly shows the treatment is having a toxic effect on viability or development. An increased germination rate would imply no toxicity; a color change by itself isn’t a reliable sole indicator, and no difference from untreated means there’s no evidence of phytotoxicity.