Regenerative Effect of L-Ascorbic Acid on the in vitro Grown Plants

Aim: In the present work, we have studied the effect of L ascorbic acid (LAA) on the regeneration of plants from different families cultured in vitro.

Study Design: Plants belonging to three different families are cultured in Murashige and Skoog (MS) medium with and without 1µg/ml L ascorbic acid (LAA), in the absence of any other growth regulators. Thus the study brings out the effect of LAA on plant regeneration. In addition regeneration capacity of LAA involving other growth regulators was also studied.

Place and Duration of Study: Department of Biotechnology, Mount Carmel College, Bangalore, India, between August 2012-August 2013.

Methodology: The work was conducted on Centella asiatica, Santalum album, and Trigonella foenumgraecum. C. asiatica and T. foenumgraecum are herbaceous whereas S. album is a tropical woody plant. Stem explants of C. asiatica and S. album and the seed explants of T. foenumgraecum were used for the in vitro culture and chlorophyll content in thus obtained leaflets was measured. Further, growth related parameters such as shoot/root length, leaf areas were measured.

Results: LAA aided the shoot regeneration in all the three plants cultured in vitro. In C. asiatica and T. foenumgraecum it resulted in the regeneration of plantlets with shoots and roots, however in the case of S. album only shoot regeneration occurred. Chlorophyll content was found to be higher in the in vitro plants grown in the presence of LAA. Shoot/root lengths and area of leaves were more in LAA grown plants as compared to control plants.

Conclusion: In vitro culture of stem explants of C. asiatica and seed explants of T. foenumgraecum revealed that supplementing LAA aided in the whole plant regeneration, whereas in the case of S. album supplementing LAA only resulted in the shoot regeneration, but no root formation. Shoot/root lengths, area of leaves and chlorophyll content was found to be higher in the in vitro grown plants with LAA as compared to those grown without LAA, suggesting that LAA is mitigating the function of both auxin and cytokinin. Enhanced chlorophyll production in in-vitro grown plants with LAA is suggestive of involvement of LAA in chlorophyll biosynthesis/protection from degradation and hence the regeneration. Through our results, we show that using LAA in the culture medium can result in regeneration of whole plants. The effect was observed in plants belonging to different families indicating LAA could be used as a general growth enhancer and adding LAA would be beneficial in the regeneration of whole plants.