Canna rust a medium threat to biosecurity and agriculture. The Canna rust damages the crop and can impact all of its potential uses by damaging photosynthetic material and reducing plant productivity and value. In the United States it is a popular ornamental for home gardens. The rust lowers the value of lilies for sale and can kill canna plants that home gardeners are trying to grow themselves. Canna rust Canna rust is a fungal disease of canna caused by "Puccinia thaliae". Symptoms include yellow to tan spots on the plant's leaves and stems. Initial disease symptoms will result in scattered sori (clustered
Human uses of plants or dried flowers. Ornamental plants have sometimes changed the course of history, as in tulipomania. Basic biological research has often been done with plants. In genetics, the breeding of pea plants allowed Gregor Mendel to derive the basic laws governing inheritance, and examination of chromosomes in maize allowed Barbara McClintock to demonstrate their connection to inherited traits. The plant "Arabidopsis thaliana" is used in laboratories as a model organism to understand how genes control the growth and development of plant structures. NASA predicts that space stations or space colonies will one day rely on plants for life support. Scientific advances