title: Eliminating aluminum toxicity in an acid sulfate soil for rice cultivation using plant growth promoting bacteria.
abstract: Aluminum toxicity is widely considered as the most important limiting factor for plants growing in acid sulfate soils. A study was conducted in laboratory and in field to ameliorate Al toxicity using plant growth promoting bacteria (PGPB), ground magnesium limestone (GML) and ground basalt. Five-day-old rice seedlings were inoculated by Bacillus sp., Stenotrophomonas maltophila, Burkholderia thailandensis and Burkholderia seminalis and grown for 21 days in Hoagland solution (pH 4.0) at various Al concentrations (0, 50 and 100 μM). Toxicity symptoms in root and leaf were studied using scanning electron microscope. In the field, biofertilizer (PGPB), GML and basalt were applied (4 t·ha-1 each). Results showed that Al severely affected the growth of rice. At high concentrations, the root surface was ruptured, leading to cell collapse; however, no damages were observed in the PGPB inoculated seedlings. After 21 days of inoculation, solution pH increased to >6.0, while the control treatment remained same. Field study showed that the highest rice growth and yield were obtained in the bio-fertilizer and GML treatments. This study showed that Al toxicity was reduced by PGPB via production of organic acids that were able to chelate the Al and the production of polysaccharides that increased solution pH. The release of phytohormones further enhanced rice growth that resulted in yield increase.
authors.affiliation: Department of Land Management, Faculty of Agriculture, Universiti Putra Malaysia, UPM Serdang, Selangor 43400, Malaysia.|Soil Chemistry Section, Agricultural Research Institute, Tandojam 70060, Sindh, Pakistan.
authors.forename: Qurban Ali
authors.initials: QA
authors.lastname: Panhwar
authors.affiliation: Institute of Tropical Agriculture, Universiti Putra Malaysia, UPM Serdang, Selangor 43400, Malaysia.|Bangladesh Rice Research Institute, Gazipur 1701, Bangladesh.
authors.forename: Umme Aminun
authors.initials: UA
authors.lastname: Naher
authors.affiliation: Department of Land Management, Faculty of Agriculture, Universiti Putra Malaysia, UPM Serdang, Selangor 43400, Malaysia.|Institute of Tropical Agriculture, Universiti Putra Malaysia, UPM Serdang, Selangor 43400, Malaysia.
authors.forename: Othman
authors.initials: O
authors.lastname: Radziah
authors.affiliation: Department of Land Management, Faculty of Agriculture, Universiti Putra Malaysia, UPM Serdang, Selangor 43400, Malaysia. shamshud@upm.edu.my.|Institute of Tropical Agriculture, Universiti Putra Malaysia, UPM Serdang, Selangor 43400, Malaysia. shamshud@upm.edu.my.
authors.forename: Jusop
authors.initials: J
authors.lastname: Shamshuddin
authors.affiliation: Institute of Tropical Agriculture, Universiti Putra Malaysia, UPM Serdang, Selangor 43400, Malaysia.
authors.forename: Ismail Mohd
authors.initials: IM
authors.lastname: Razi
mesh_terms: D000535:Aluminum / Q000633:toxicity*; D001419:Bacteria / Q000302:isolation & purification / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D005308:Fertilizers; D006863:Hydrogen-Ion Concentration; D008274:Magnesium / Q000494:pharmacology*; D012275:Oryza / Q000187:drug effects / Q000254:growth & development* / Q000382:microbiology*; D018515:Plant Leaves / Q000187:drug effects / Q000254:growth & development; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development; D036226:Seedlings / Q000187:drug effects / Q000254:growth & development*; D012987:Soil / Q000737:chemistry*; D012988:Soil Microbiology
chemical_list: D005308:Fertilizers; D012987:Soil; D000535:Aluminum; D008274:Magnesium