Grafting micropropagated tea [Camellia sinensis (L.) O. Kuntze] shoots on tea seedlings - a new approach to tea propagation

Tea microshoots excised from well-established multiple shoot cultures grown in vitro and 8-week-old, three- to five-leaved seedlings from a local chin ery stock (Banuri-96) and UPASI-9 (from southern India) were selected as sc ions and root stocks, respectively, for grafting. In addition, 4-month- and 12-month-old seedlings of Banuri-96 were also used as root stocks. Cut end s of root stocks and scions were pretreated with varying concentrations of BAP and NAA for 10 min. A treatment of BAP (5 mg/l) and NAA (5 mg/l) to bot h scion and stocks in water renewed foliar development at a relatively earl y stage (40-60 days). The grafted plants were kept in hardening chambers wi th CO2-enriched air. No significant difference was observed between autogra ft (scion and root stock of Banuri clone) and heterograft (scion of the Ban uri clone and root stock of UPASI-9). Of the three types (in terms of age) of seedling-raised root stocks employed, grafts on young tea (4-month-old) performed the best (88.33%). Grafts made in early summer established relati vely faster and at a high rate of success. The percentage survival of plant s transferred to the field was 88.33%.