title: The response of maize (Zea mays L.) plant assisted with bacterial consortium and fertilizer under oily sludge.
abstract: The objective of this study was to evaluate the role of PGPR consortium and fertilizer alone and in combination on the physiology of maize grown under oily sludge stress environment as well on the soil nutrient status. Consortium was prepared from Bacillus cereus (Acc KR232400), Bacillus altitudinis (Acc KF859970), Comamonas (Delftia) belonging to family Comamonadacea (Acc KF859971) and Stenotrophomonasmaltophilia (Acc KF859973). The experiment was conducted in pots with complete randomized design with four replicates and kept in field. Oily sludge was mixed in ml and Ammonium nitrate and Diammonium phosphate (DAP) were added at 70 ug/g and 7 ug/g at sowing. The plant was harvested at 21 d for estimation of protein, proline and antioxidant enzymes superoxide dismutase (SOD) and peroxidase (POD). To study the degradation, total petroleum hydrocarbon was extracted by soxhelt extraction and extract was analyzed by GC-FID at different period after incubation. Combined application of consortium and fertilizer enhanced the germination %, protein and, proline content by 90,130 and 99% higher than untreated maize plants. Bioavailability of macro and micro nutrient was also enhanced with consortium and fertilizer in oily sludge. The consortium and fertilizer in combined treatment decreased the superoxide dismutase (SOD), peroxidase dismutase (POD) of the maize leaves grown in oily sludge. Degradation of total petroleum hydrocarbon (TPHs) was 59% higher in combined application of consortium and fertilizer than untreated maize at 3 d. The bacterial consortium can enhanced the maize tolerance to oily sludge and enhanced degradation of total petroleum hydrocarbon (TPHs). The maize can be considered as tolerant plant species to remediate oily sludge contaminated soils.
authors.affiliation: a Quaid-i-Azam University , Islamabad , Pakistan.
authors.forename: Asim
authors.initials: A
authors.lastname: Shahzad
authors.affiliation: b National Center for Excellence in Geology , University of Peshawar , Pakistan.
authors.forename: Samina
authors.initials: S
authors.lastname: Saddiqui
authors.affiliation: a Quaid-i-Azam University , Islamabad , Pakistan.
authors.forename: Asghari
authors.initials: A
authors.lastname: Bano
mesh_terms: D001407:Bacillus / Q000378:metabolism; D001419:Bacteria / Q000378:metabolism*; D001673:Biodegradation, Environmental; D020585:Comamonas / Q000378:metabolism; D005308:Fertilizers; D010578:Petroleum / Q000378:metabolism*; D012722:Sewage; D012987:Soil; D020615:Stenotrophomonas maltophilia / Q000378:metabolism; D003313:Zea mays / Q000378:metabolism* / Q000382:microbiology
chemical_list: D005308:Fertilizers; D010578:Petroleum; D012722:Sewage; D012987:Soil
keywords: Oily sludge; antioxidant enzymes; biodegradation; oxidative stress; phytoremediation