The extracts of Piper sarmentosum Roxb., Piper retrofractum Vahl, Piper interruptum Opiz and Piper nigrum plants belonging to the family Piperaceae were evaluated for their efficacy against diamondback moth, Plutello xylostella L. third instars under laboratory conditions. Comparative toxicity of
BACKGROUND
Benjakul, a Thai traditional herbal preparation, comnprises five plants: Piper chaba, Piper sarmentosum, Piper interruptum, Plumbago indica, and Zingiber officinale. It has widely been used to treat cancer patients in folk medicine in Thailand. Benjakul extract, and its isolated compounds