In vitro Floral Induction of Cuscuta reflexa

Background

Cuscuta reflexa is a parasitic angiosperm parasitizing on a huge number of angiosperms (Kuijt, 1969). The ability to cause severe damage and loss of yield in the host plant has made this species important for scientific study (Nun and Mayer, 1999). Most of the Cuscuta species are non chloroplastic except few which have functional chloroplasts (Hibberd et al., 1998). Development of seedlings from larger embryos of C. reflexa in white’s medium has been reported (Maheshweri and Baldev, 1961). Floral induction of C. reflexa in short day period as well as dark conditions has been seen in vitro (Baldev, 1962). In vitro floral induction of Cuscuta japonica in short day conditions has also been established by Furuhashi et al. (1991).

Specifically, floral induction and effect of growth regulators on floral induction of C. reflexa has not yet been studied. A complete tissue culture system for Cuscuta trifolli in liquid MS culture has been reported so far (Bakos et al., 1995). The floral induction in C. reflexa on modified white’s medium, subjecting the plant to different light and dark conditions, has been studied years back (Baldev, 1962). Here we have shown a complete in vitro culture system for floral induction in C. reflexa. Concentration of 2,4-D played a significant role in floral induction. Supplementation of NAA along with 2,4-D induces shoot followed by flower, but supplementation of only 2,4-D induces flower directly from nodal explants without showing any stem elongation. This result is very attractive and is showing the importance of 2,4-D in floral induction of this plant.