The Endophyte Bacteria Isolated from Java Coastal Plants Promote Plant Growth and Induce Salt Tolerance of Two Rice Varieties

Bacteria associated with plants grown in saline natural habitats may be a key factor in the mechanisms responsible for some plants’ tolerance of saline environments. To be able to utilize this plant-microbe interaction to alleviate the salt stress on plants growing under saline conditions would be of great benefit to crops like rice grown in coastal areas subject to salt water intrusion due to rising sea water levels.  With the objective of finding the most promising bacteria that were able to induce salt tolerance in plants growing in tidal coastal areas of Indonesia, we evaluated 9 bacterial isolates that had previously been isolated from plants grown in the Java coastal area.   A Greenhouse trial was carried out to evaluate the ability of these isolates to improve salt tolerance in two rice varieties (Ciherang and IF8) under different concentrations of NaCl.  The results suggest that promising bacterial isolates E194-3, D205-1 and R146-6 might enhance salt tolerance in rice plants for ischolar_main endophyte, leaf endophyte and rhizoplane respectively.  These isolates gave the best effect on plants height, shoot dry weight, ischolar_main length and ischolar_main dry weight in both rice varieties tested Ciherang and IF8.