Perennial peanut has many benefits as both a ground cover and forage. In fact, one of its best features is its resistance to nematodes, pathogens, and drought. However, if you have an older variety like ‘Florigraze’ and notice your perennial peanut is yellow, stunted, and has malformed leaves, it could be suffering from peanut stunt virus (PSV).
Peanut stunt virus is a member of the family Bromoviridae. This virus is in the same genus as the cucumber mosaic virus (Cucumovirus). The virus is transmitted by the seeds of peanuts and is then vectored by several aphid species. PSV infects a number of different crops such as cultivated peanuts, tobacco, and soybeans. In the Southeastern United Stated it has also infected forage legumes, especially clover. Of all the perennial peanut varieties, ‘Florigraze’ seems to be the most susceptible to PSV.
Perennial peanut that has PSV can exhibit symptoms such as chlorosis, mottling, malformed leaves, and stunting. Since PSV affects the root system of the plant it results in overall forage yield reduction. The chlorosis of the leaves will cause a yellowing appearance across the field. In addition, the leaves may begin to display leaf spotting. In some cases, infected perennial peanut may show no signs of the virus at all. Diagnostic testing of the rhizomes and leaves in a laboratory can confirm the presence of PSV.
Unfortunately, there is no cure for PSV at this time. Although ‘Florigraze’ is one of the most widely planted perennial peanut varieties with an estimated 30,000 planted acres, over time the development of PSV has caused it to drop in popularity. A possible solution to a heavily PSV infested field could be renovating with a newer variety. Two newer perennial peanut hay varieties such as ‘UF Tito’ and ‘UF Peace’ are more productive and less susceptible to PSV.
Click here to watch the 2020 Virtual Perennial Peanut Field Day to learn more about the different ornamental and forage varieties of perennial peanut.