IN-VITRO PROPAGATION OF WRIGHTIA-TINCTORIA

In vitro method has been developed for propagation of Wrightia tinctor ia R.Br. using cotyledonary node segments. Murashige and Skoog's (MS) medium supplemented with 5.0 mg dm-3 of 6-benzylaminopurine (BAP) and 0.01 mg dm-3 of naphthaleneacetic acid (NAA) induced up to eight shoot s per explant with an average shoot length of 1.4 cm in 21 d. Three fo ld multiplication rate was achieved during every subculture of regener ated shoots on the same medium producing an average of 230 shoots per node within 84 d. Reduction in BAP concentration from 5.0 to 1.0 mg dm -3 during subculture promoted shoot length without affecting the rate of multiplication. The differentiated shoots could be rooted by a dip treatment into preautoclaved indole-3-butyric acid (IBA - 500 mg dm-3 for 5 min) followed by their implantation onto MS medium containing 1/ 4 salts. Rooting was observed within 8 - 10 d in approximately 80 % of shoots inoculated after IBA treatment. 15 d after rooting, the plantl ets were transferred to culture bottles containing soil-Soilrite(TM) ( 1:1) and liquid nutrient solution comprising 1/4 MS salts. After their partial hardening in these bottles for 10 d they were transferred to pots containing soil-Soilrite (1:1) mixture with 60 % transplantation success. Methods are being standardized to improve the rate of surviva l and large scale field transfer.