MIEKE ROCHIMI SETIAWATI, PUJAWATI SURYATMANA, REGINAWANTI HINDERSAH, BETTY NATALIE FITRIATIN, ANNE NURBAITY, DIYAN HERDIYANTORO, NADIA NURANIYA KAMALUDDIN AND TUALAR SIMARMATA
Abstract
Saline agricultural soil have a great prospect for expanding the lowland rice cultivation and aid the rice production in Indonesia. Salinity and low nutrients status are the main constraints for rice cultivation and will influence rice growth and productivity. This research investigated the biodiversity and potential of plant growth promoting and N fixing bacteria (NFEB) under field and green house condition. One-month-old rice seedlings (Ciherang var.) were taken from various saline ecosystem in Pantura West Java. The NFEB were isolated and enumerated using plate dilution methods containing nitrogen free agar (JNFb) media. Selected isolates were subjected to acetylene reduction assay (ARA) and phytohormone production. Selected isolates were used to formulate the N-fixer inoculant and subjected to biomolecular test. From the roots, stems, and leaves of rice seedlings 18 endophytic bacteria isolates were obtained. Substantial nitrogenase activity and indole-3-acetic acid (IAA) phytohormone were recorded from 9 isolates. The amounts of produced IAA in culture varied between 10.750 - 16.724 ppm. All bacterial endophytes demonstrated the ability to produce cytokinin (zeatin and kinetin) and gibberellin that could contribute to enhance the plants growth.