title: Exploring the efficacy of wastewater-grown microalgal biomass as a biofertilizer for wheat.
abstract: Microalgae possess the ability to grow and glean nutrients from wastewater; such wastewater-grown biomass can be used as a biofertilizer for crops. The present investigation was undertaken to evaluate two formulations (formulation with unicellular microalgae (MC1) and formulation with filamentous microalgae (MC2); T4 and T5, respectively), prepared using wastewater-grown microalgal biomass, as a biofertilizer (after mixing with vermiculite/compost as a carrier) in wheat crop (Triticum aestivum L. HD2967) under controlled conditions. The highest values of available nitrogen (N), phosphorus (P), and potassium (K) in soil and nitrogen-fixing potential were recorded in treatment T5 (75% N + full-dose PK + formulation with filamentous microalgae (MC2). Microbial biomass carbon was significantly enhanced by 31.8-67.0% in both the inoculated treatments over control (recommended dose of fertilizers), with highest values in T4 (75% N + full-dose PK + formulation with unicellular microalgae (MC1)). Both the microalgal formulations significantly increased the N, P, and K content of roots, shoots, and grains, and the highest total N content of 3.56% in grains was observed in treatment T5. At harvest stage, the treatments inoculated with microalgal formulations (T4 and T5) recorded a 7.4-33% increase in plant dry weight and up to 10% in spike weight. The values of 1000-grain weight showed an enhancement of 5.6-8.4%, compared with T1 (recommended doses of fertilizers). A positive correlation was observed between soil nutrient availability at mid crop stage and plant biometrical parameters at harvest stage. This study revealed the promise of such microalgal consortia as a biofertilizer for 25% N savings and improved yields of wheat crop.
authors.affiliation: Department of Botany, Panjab University, Chandigarh, 160014, India.
authors.forename: Nirmal
authors.initials: N
authors.lastname: Renuka
authors.affiliation: Division of Microbiology, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India. radhapr@gmail.com.
authors.forename: Radha
authors.initials: R
authors.lastname: Prasanna
authors.affiliation: Division of Microbiology, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India.
authors.forename: Anjuli
authors.initials: A
authors.lastname: Sood
authors.affiliation: Department of Botany, Panjab University, Chandigarh, 160014, India.
authors.forename: Amrik S
authors.initials: AS
authors.lastname: Ahluwalia
authors.affiliation: Division of Agronomy, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India.
authors.forename: Radhika
authors.initials: R
authors.lastname: Bansal
authors.affiliation: Division of Microbiology, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India.
authors.forename: Santosh
authors.initials: S
authors.lastname: Babu
authors.affiliation: Water Technology Centre, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India.
authors.forename: Rajendra
authors.initials: R
authors.lastname: Singh
authors.affiliation: Division of Agronomy, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India.
authors.forename: Yashbir S
authors.initials: YS
authors.lastname: Shivay
authors.affiliation: Division of Microbiology, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India.
authors.forename: Lata
authors.initials: L
authors.lastname: Nain
mesh_terms: D018533:Biomass; D002244:Carbon / Q000032:analysis; D018556:Crops, Agricultural / Q000737:chemistry / Q000254:growth & development*; D005308:Fertilizers / Q000032:analysis*; D058086:Microalgae / Q000737:chemistry* / Q000254:growth & development; D009584:Nitrogen / Q000032:analysis; D010758:Phosphorus / Q000032:analysis; D012987:Soil / Q000737:chemistry*; D014908:Triticum / Q000737:chemistry / Q000254:growth & development*; D062065:Wastewater
chemical_list: D002244:Carbon; D005308:Fertilizers; D009584:Nitrogen; D010758:Phosphorus; D012987:Soil; D062065:Wastewater
keywords: Microalgae; Microbial biomass carbon; Nutrient availability; Plant nutrition; Soil fertility; Yield