Tuesday, November 25, 2008

Did you know...

that there are two plant diseases that are specifically regulated by the state of NC? Both Potato Virus Y and White Pine Blister Rust have laws on the books that regulate plant movement into NC.

Potato Virus Y is a plant pathogen that is spread by aphids and infects crops including potatoes, tomatoes and tobacco. NC regulation prohibits the movement of tobacco and tomato transplants from areas of Florida south of and including Dixie, Gilchrist, Alachua, Putnam and Flagler Counties. Plants that were brought to NC from these areas have tested positive for Potato Virus Y. Though Potato Virus Y occurs annually in NC, it is not able to overwinter here. This regulation helps to prevent or slow down the build up on the virus in our agricultural fields. Plants that are grown in greenhouses in the areas mentioned above that are certified as grown in an aphid-free environment can be purchased and planted in NC.

The second plant disease is White Pine Blister Rust caused by the fungus Cronartium ribicola. Currants, gooseberries and other plants in the genus Ribes cannot be legally brought into or grown in NC. Ribes spp. are alternate hosts for the pathogen that causes White Pine Blister Rust, the most devastating disease of the white pine (including Pinus strobis). This is an old law, however there is still an active eradication of native currants in WNC within a certain distance of white pine plantations as young white pines are rather susceptible. Though many cultivated varieties of currants and gooseberries claim to be resistant to White Pine Blister Rust, there is not significant scientific evidence of the claim. Researchers are actively researching this subject.

To find out more about these regulations visit the NCDA&CS Plant Industry-Plant Protection Section.