At least 75,000 plants species are believed to be edible. However, we rely on a mere 20 plant species to provide over 80% of the world 's nutritional needs. Over half of our caloric intake is supplied by just three grasses: wheat, rice and corn.

Many endangered plants are close relatives of valuable crops. Plant extinction not only weakens natural ecosystems and their ability to adapt to change, but also it tragically reduces the beauty and diversity of life around us. Furthermore it depletes the irreplaceable gene pool that may hold the key to cures for cancer, ending world hunger, or controlling agricultural pests. For example:

Texas wild-rice (or Zizania texania), once much more abundant, is now restricted to a small section of a single stream in Texas. It is being bred with northern wild rice to develop a new strain suitable for mild climates.

Without concerted conservation action, Texas wild-rice could become extinct in the wild within five years.

Okeechobee gourd (Cucurbita okeechobensis) from the squash family is another rare plant of interest to plant breeders because it is resistant to certain viruses.

This plant, a native of Florida, is nearly extinct, because its habitat has been cleared for farming.