THE EFFECT OF SALINITY TO ACTIVITY AND EFFECTIVITY PHOSPHATE SOLUBILIZING BACTERIA ON GROWTH AND PRODUCTION OF PADDY

This study aimed to determine the extent of phosphate solubilizing bacteria resistant to salinity and still be able to provide P for paddy plant. Research using completely randomized design with fertilizer treatments: (A) Bakteri Aerobacter aerogenes + Azotobacter indicus (B) Bakteri Bacillus thuringiensis + B. megaterium + Pseudomonas fluorescens, (C) Bakteri Nocardia mesentrica + Spirillum lipoferum, (D) Mix bakteri Pseudomonas fluorescens, Bacillus thuringiensis, B. megaterium, Nocardia mesentrica, Aerobacter aerogenes, Spirillum lipoferum, dan Azotobacter indicus, and (E) control (whitout inoculant), and salinity (NaCl): (1) 0% (0 grams / 7 kg soil), (2) 0.1% (7 grams / 7 kg soil), (3) 0.2% (14 g / 7 kg soil), (4) 0.3% (21 g / 7 kg soil), and (5) 0 , 4% (28 g / 7 kg soil). Thirty and one hundred days after transplanting (DAT), and then measured plant height, number of tillers, number and dry weight of whole grain paddy. The results showed that 0,1 % (7 gram/7 kg tanah) salinity is very good for the growth, activity and effectiveness of phosphate solubilizing bacteria and production of paddy, but 0.4% salinity (28 gr/7kg land) is still safe on the growth, activity and effectiveness of phosphate solubilizing bacteria (Pseudomonas fluorescens, Bacillus thuringiensis, B. megaterium, Nocardia mesentrica, Aerobacter aerogenes, spirillum lipoferum and Azotobacter indicus) as biofertilizer or growth promoting rhizobacteria on growth and production of paddy.Keywords: Salinity, Phosphate solubilizing bacteria, Padd

Potency of Rhizosphere Bacteria to Promote Rice Growth Under Saline Condition

Saline soil is a common problem in coastal paddy field, especially in Indonesia. Salinity affects rice growth and the activities of soil functional microbes, including functional bacteria, which play roles in plant growth. Some of these microbes are associated with rice plants and are able to survive under saline condition. The presence of functional microbes is also important to improve soil quality. Nitrogen and phosphate are essential soil nutrients and is available in soil due to the activities of nitrogen-fixing bacteria and free-living plant-associated bacteria. The objective of the present study was to obtain nitrogen-fixing, phosphate solubilizing and Indole Acetic Acid (IAA)-producing bacteria that are able to survive and promote the growth of rice under saline conditions. From rice and peanut rhizosphere, Ca-phosphate (Ca-P) solubilizing and nitrogen-fixing bacteria were isolated separately using specific media. Then, the Ca-P solubilizing ability, phosphomonoesterase activity and IAA-producing ability were quantitatively examined. Based on the abilities, 20 strains were selected and identified as Burkholderia cepacia-complex, Burkholderia anthina, Burkholderia cenocepacia, Bacillus cereus-complex (three strains), Achromobacter spanius, Azospirillum sp. (four strains), Azotobacter sp. (three strains), Rhizobium leguminosarum, Rhizobium sp. (two strains), and Pseudomonas sp. (three strains). The inoculation of several single strains or the mixture of the selected strains promoted the growth of rice under saline conditions. These inoculants could be potential as biofertilizer in saline paddy fields

PHYTASE PRODUCTION BY Enterobacter cloacae

 This study aims to isolate the phytase producing bacteria (PPB), a plant growth promoting rhizobacteria (PGPR), from 1Cigna sinensis rhizosphere and to optimize its physicochemical conditioning. Phytase is an enzyme that can hydrolyze the phosphoester bond in organic phosphorus (phytic acid) to form ester phosphate and inorganic phosphate, the available forms of phosphorus. To test its ability to hydrolyze organic phosphates (calcium phytate), the phytase was screened in solid and liquid phytase screening medium (PSM). After isolation, a total of 13 bacteria were positive for this enzyme’s production as indicated by the clear zones of hydrolysis observed around the colony. Enterobacter cloacae strain B1 had the largest hydrolysis efficient (3.43) on solid medium. The phytase-production of the Enterobacter cloacae strain grown in liquid PSM, showed 0.92 U/mL after 48 hours of incubation. This strain produced optimum levels of phytase in the presence of lactose and monoammonium phosphate (NH4H2PO4), as carbon and nitrogen sources, respectively, at 30 °C and pH 5.0. The PPB obtained in this study are recommended for further research as to their use as plant biological fertilizers. Â

Effect of Plant Growth Promoting Rhizobacteria and Molasses on Seed Germination and Seedling Growth of Sorghum bicolor L.Moench

Germination is the first step of the activity of plant growth. It is important for the next step in the field. The aim of the study was to evaluate the effect of PGPR and molasseson both germination (in vitro and soil) of Sorghum bicolor. The PGPR inoculants used were Phosphate Solubilizing Bacteria (Bacillus sp.) and Nitrogen Fixing Bacteria (Azospirillum sp, Azotobacter sp). Sorghum seed were treated with PGPR (sole and mixed inoculation) and molasses either singly or in combination. The result showed that in vitro experiment, seed inoculation significantly enhanced root and shoot length, and index vigour of sorghum. Conversely, seed germination were negatively affected by molasses application. In pot experiment, the application of both PGPR and molasses increased root and shoot length, and also root and shoot dry weight. The highest root and shoot length, root and shoot dry weight was obtained with s eed treated in combination PGPR mixed inoculation and molasses

THE POPULATION OF NITROGEN FIXING BACTERIA AND PHOSPHATE SOLUBILIZING BACTERIA IN THE RHIZOSPHERE FROM GUNUNG HALIMUN NATIONAL PARK

The biodiversity of nitrogen fixing bacteria (Rhizobium, Azotobacter and Azospirillum) and phosphate solubilizing bacteria in rhizosphere collected from Gunung Halimun National Park were studied.Bacterial population was counted from soil rhizosphere collected from various ecosystem types (determined based on elevation) namely 600 m, 1000 m, 1100 m, 1500 m and 1800 m above sea level.The results showed that the highest population of N-fixing and P solubilizing bacteria at Cikaniki (1100 asl) are founded in the plant rhizosphere of Schima wallichii in plot Suzuki A I and Altingia exelsa in Suzuki A III,at Gunung Botol area is in 1000 m asl,and Ciptarasa area is in 600 m asl.The population of N-fixing and P solubilizing bacteria at Gunung Halimun was influenced by the vegetation type, soil pH,and the elevation of area. Rhizobium, Azotobacter, Azospirillum (N-fixing bacteria); Pseudomonas sp, and Bacillus megaterium (P solubilizing bacteria), are most dominant at 600 m, 1000 m and 1100 m asl

POTENCY OF RHIZOSPHERE BACTERIA TO PROMOTE RICE GROWTH UNDER SALINE CONDITION

Saline soil is a common problem in coastal paddy field, especially in Indonesia. Salinity affects rice growth and the activities of soil functional microbes, including functional bacteria, which play roles in plant growth. Some of these microbes are associated with rice plants and are able to survive under saline condition. The presence of functional microbes is also important to improve soil quality. Nitrogen and phosphate are essential soil nutrients and is available in soil due to the activities of nitrogen-fixing bacteria and free-living plant-associated bacteria.  The objective of the present study was to obtain nitrogen-fixing, phosphate solubilizing and Indole Acetic Acid  (IAA)-producing bacteria that are able to survive and promote the growth of rice under saline conditions. From rice and peanut rhizosphere, Ca-phosphate (Ca-P) solubilizing and nitrogen-fixing bacteria were isolated separately using specific media. Then, the Ca-P solubilizing ability, phosphomonoesterase activity and IAA-producing ability were quantitatively examined. Based on the abilities, 20 strains were selected and identified as Burkholderia cepacia-complex, Burkholderia anthina, Burkholderia cenocepacia, Bacillus cereus-complex (three strains), Achromobacter spanius, Azospirillum sp. (four strains), Azotobacter sp. (three strains), Rhizobium leguminosarum, Rhizobium sp. (two strains), and Pseudomonas sp. (three strains). The inoculation of several single strains or the mixture of the selected strains promoted the growth of rice under saline conditions. These inoculants could be potential as biofertilizer in saline paddy fields