ELIMINATION OF ORNITHOGALUM MOSAIC-VIRUS FROM CHINCHERINCHEE (ORNITHOGALUM-THYROSIDES) BY MERISTEM TIP CULTURE, AND FIELD TRIALS OF REINFECTION

Meristem domes excised from plantlets of Ornithogalum thyrsoides infec ted with ornithogalum mosaic virus (OrMV) in Kenya were cultured on ba sic Murashige and Skoog medium without added growth hormones. Of the r esulting plantlets 30% were virus-free as determined by symptom appear ance, mechanical inoculation to virus-free O. thyrsoides, electron mic roscopy and serological tests. When healthy plants were placed within a field of diseased O. thyrsoides, 35% became re-infected within 4 mon ths and 100% infection was reached within 8 months. However, healthy p lants placed in isolation, about 2 km downwind of infected commercial plantings, remained healthy over the 12-month test period.