Isolasi dan uji efektivitas Plant Growth Promoting Rhizobacteria di lahan marginal pada pertumbuhan tanaman kedelai (Glycine max L. Merr.) var. Wilis

Widawati S, Suliasih, Saefudin. 2014. Isolation and effectiveness test of Plant Growth Promoting Rhizobacteria in marginal land on the growth of soybean (Glycine max L. Merr.) var. Willis. Pros Sem Nas Masy Biodiv Indon 1 (1): 59-65. A total of 14 isolates PGPR have been isolated and identified from the nodule and soybean rhizosphere soil from Cibinong (CSC) and legumes from Mount Susu, Wamena, Papua (marginal soils). The identified isolates were utilized as POH (biorganic fertilizer) to increase crop production. POH AZOFOR1 (Bradyrhizobium japonicum, Rhizobium sp.1, Rhizobium sp.2, sp.3 Rhizobium isolated from root nodules of soybean + Azotobacter and Azospirillum), AZOFOR2 (Rhizobium leguminosarum, Burkholderia cepacea, B. cenospacea, B. anthiana isolated from the rhizosphere of plants soy + Azotobacter and Azospirillum), and AZOFOS (Bacillus cereus, B. thuringiensis, B. megaterium, B. pantothenticus isolated from milk Gn + Azotobacter and Azospirillum) will be examined for its effectiveness in soybean plants. The experiments were conducted in the laboratory (analysis) and in the ex-bamboo growing area of Cibinong Science Center (effectiveness test). A randomized block design (RBD) was set with eight factorial treatments (five replications), namely: Without Fertilizer, Compost, Fertilizer Chemicals, POH AZOFOR1, POH AZOFOR2, POH AZOFOS, and POH MIX. The analysis result showed that the bacterial population, P available, PMEase, and the pH increased from 1.00 x 105 CFU/g soil; 0.65 g/L; 0.001 ug/p nitrofenol/g/h and 5.80 to 107; 0.91/0.95 g/L; 0.019/0.024/0.39 ug/p nitrofenol/g/h, and 7.1 after fostered by POH Mix, POH Azofor1, and POH azofor2. The effectiveness of all three fertilizer was observed on pod weight, seed weight, shell weight, the weight of plants per plot and per ten trees and the number of nodules and number of pods per ten trees, ie 3040; 2130; 1530 g; 1840; 1330; 860 g; 1200; 800; 670 g; 7.7; 5.8; 4.1 Kg per plot and 229.40; 227.42; 183.04 g; 130.5; 126.4; 116.37 g; 480; 440; 400 g per ten trees and 129; 119; 112 grains; 512; 483; 460 pieces per ten trees. Effectiveness of PGPR contained in POH Mix (14 isolates) showed positive effect on soil fertility (biofertilizer increased bacterial population) as well as the growth and production of soybean.