ABSTRACT
RESEARCH CONDUCTED: Rheum emodi is a perennial herb that grows at high altitudes (1800-4400m) and possesses many medicinal properties. Due to over-exploitation, the plant has become endangered in its natural habitat. The present research focuses on the effect of stress tolerance endophytic bacteria on the growth of Rheum emodi grown at lower altitudes (748ft) under salt and heavy metal stress. METHODS: Endophytic bacteria Pelomonas Aquatica AIS1S and Solibacillus silvestris DL3R2 were isolated from Abutilon indicum and Hermocallis fulva and were identified by 16s rRNA sequence. The seeds were inoculated with the bacteria and sown in sterile soil with low carbon, potassium, and phosphorous content. The growth of the plants was regularly monitored for three months. The phytochemicals of the experimental plant were compared with the in-situ plants taken as control. RESULTS: The results have shown that seeds inoculated with Pelomonas Aquatica AIS1S and Solibacillus silvestris DL3R2 have higher germination than control. The maximum number of seeds germinated is 2.33±0.47 at 2% salt concentration on inoculation with Pelomonas Aquatica AIS1S. The least number of seeds germinated is 0.33±0.47 at 6% cadmium concentration on inoculation with Pelomonas Aquatica A1S1S. HPLC analysis has shown that the 0.41%and 0.16% of quercetin and gallic were produced at higher altitudes which is less than a plant grown at a lower altitude, i.e., 0.47% 0.18%, respectively. Emodin, physcoin, and rhein are the other compounds found at 254nm. CONCLUSION: This study provides a basis that plants can be grown under stress conditions with the help of stress-tolerant endophytic bacteria, thus providing a new strategy for the conservation of plants.
