Inhibition of Velvetleaf (Abutilon theophrasti) Germination and Growth by Benzyl Isothiocyanate, a Natural Toxicant

Benzyl isothiocyanate (BITC) was extracted from mature papaya (Carica papaya L.) seeds and applied to imbibed velvetleaf (Abutilon theophrasti Medic. ♯3 ABUTH) seeds. Complete inhibition of germination occurred at a concentration of 6 × 10-4 M BITC, and only 28% (compared to controls) of the seeds germinated after 4 days exposure to the 4 × 10-4 M treatment. Corn (Zea mays L. ‘DeKalb XL-66′) was unaffected even at higher concentrations; however, 72% of imbibed soybeans [Glycine max (L.) Merr. ‘Tiger’] germinated in 6 × 10-4 M BITC. When this natural inhibitor was applied to etiolated velvetleaf seedlings at 4 × 10-4 M, 100% died in 2 days.