ISOLASI DAN KARAKTERISASI BAKTERI PELARUT POSFAT DAN PEMFIKSASI NITROGEN RIZOSFER GULMA AGERATUM CONYZOIDES DARI LAHAN KERING LOMBOK UTARA

Isolation and Characterzation Of Phosphate-Solubilizing Bacteria and Nitrogen-Fixing Bacteria from Ageratum Conyzoides Rhizosphere Found in North Lombok Dryland Area

Abstract

Agricultural development in the drylands of North Lombok is constrained by limited water availability and low levels of essential nutrients, particularly nitrogen (N) and phosphorus (P). The utilization of indigenous functional bacteria, especially phosphate-solubilizing bacteria and nitrogen-fixing bacteria represents a promising strategy for enhancing soil fertility within sustainable agricultural systems. The rhizosphere of dryland weeds, such as Ageratum conyzoides, may serve as a potential reservoir of these beneficial bacteria due to their adaptation to nutrient-deficient and water-limited environments. This study aimed to isolate and identify potential PSB and NFB candidates from Ageratum conyzoides growing in the drylands of Selengen Village, North Lombok. The research was conduct by isolating the rhizobacteria from Ageratum conyzoides rhizosphere. The isolates then transfered into pikovskaya medium for phosphate solubilizing test and Jensen medium for Nitrogen fixation tes. The results revealed seven PSB isolates, designated as isolates 4.1, 4.2, 4.4, 4.5, 4.7, 4.8, and 4.10. Nitrogen fixation screening identified five NFB isolates from the rhizosphere of A. conyzoides, namely isolates 4.1, 4.3, 4.6, 4.8, and 4.9.