Evaluation of Tip Culture, Thermotherapy and Chemotherapy for Elimination of Peanut Mottle Virus from Arachis hypogaea

Peanut (Arachis hypogaea L.) plants (cvs Florunner and Pronto) were inoculated at the two-leaf stage with peanut mottle virus (PMV) to obtain PMV-infected plants. Shoot-tips from plants grown in the glasshouse (27°C) or from plants maintained at 35°C were used for tip culture. In some experiments ribavirin was added to the culture medium at 5 mg/1, 10 mg/1, 15 mg/1 or 20 mg/1. Plants regenerated from meristems or shoot-tips taken from virus-infected plants were not virus-free. After 45 days at 35°C, foliar tissue of 93 % of Florunner and 95 % of Pronto plants tested negative for PMV by enzyme-linked immunosorbent assay (ELISA). When shoot-tips from the plant that tested negative by ELISA were used for tip culture, no virus-free plants were obtained. No virus-free plants were obtained from tips cultured on medium supplemnted with ribavirin. However, when tip culture, thermotherapy and chemotherapy were combined; 80 % of Florunner and 100 % of Pronto plants were found negative for PMV.