The use of transgenic (Bt) cotton (Ingard® and more recently Bollgard II®) has greatly reduced the use of insecticides in Australian cotton production and the status of key lepidopteran pests such as Helicoverpa spp.

The floral organs and wounded leaves of Nicotiana alata, the ornamental tobacco, produce a serine protease precursor molecule (NaPI) which is cleaved into six individual inhibitors of 6 kDa.