Determining the Effectiveness of Cryotherapy to Eliminate Plant Virus in Potato

Potatoes are vegetatively propagated which allows for the passage of viral diseases from one generation to the next, making it possible for entire clonal populations to become infected with the same pathogen (Kassins et al., 1957). This makes virus eradication an extremely valuable management tool in potato production. It has recently been acknowledged that cryotherapy is an effective method for removing viruses from plant shoot tips (Wang et al., 2003, 2008). Specifically, cryotherapy involves the excision of shoot tips which are frozen in liquid nitrogen, then cultured in a sterile environment until cells regenerate into plants. This study used ELISA testing to document existing viruses in potato varieties MN02696, MN18747, MN99460-14, COMN04788-04, COMN04788-09, and COMN04692-11 and subjected plant material to two different cryotherapy methods; treatment one (encapsulation method) and treatment two (vitrification method). Treatment one involved three replications; replication two decreased the length of the liquid nitrogen exposure and replication three double coated the beads with a sodium alginate solution. Plant material did not survive in any replications of treatment one, however, plant survival was noted in treatment two. Three weeks after treatment two, plant material was evaluated for survivability. Varieties COMN0477-04, MN 18747, and MN 99460-14 appeared to have the highest levels of survival. Some varieties