There was no significant difference in length and width of leaf and number of leaves per plant between tissue-cultured plants and conventionally propagated ones but chlorophyll content increased in tissue-cultured ones. Percent of sprouting from planted root segments significantly increased in tissue-cultured plants, resulting in yield increase of more than 200% per 10a. Root thickness of tissue-cultured plants at the time of planting influenced percent of sprouting and yield. Plants with root diameter ranging from 3 to 6mm gave good yield. When virus infection was monitored with N. tabacum and C. amaranticolor as indicator plants, 100% infection occurred in vegetatively propagated plants and introduced plants from China. whereas plants obtained from apical meristem showed 0% and 40% to 45% infection in vitro plantlets and 1 year old plants in vivo, respectively. Tobamovirus and unidentified virus particles were detected in electron microscopy.