Which growth phase is associated with higher cyanide content in plants?

• A. Environmental stress
• B. Phase of plant growth (young rapid growth or regrowth)
• C. Soil pH
• D. Plant species

Answer: (B)

Cyanide content in plants tends to be highest when tissues are actively growing. During a young, rapid-growth phase or when plants are regenerating after damage, they invest in producing cyanogenic glycosides to defend tender new tissue. This defense is most needed when cells are expanding and vulnerable, so the cyanide levels peak then. As tissues mature and growth slows, concentrations drop due to dilution and changes in metabolism. Environmental stress and plant species can influence overall levels, but the growth stage best explains the peak in cyanide content within a plant.