Comparative Impact of Bio-Organic and Inorganic Fertilizer Application on Soil Health, Grain Quality and Yield Stability in Nutrient Deficient Regions

Abstract. Soil fertility limitations in arid regions restrict wheat productivity and grain nutritional quality, with zinc (Zn) deficiency being a major concern. Sustainable soil amendments combining organic and microbial inputs offer potential to address these constraints. This study aimed to evaluate the effectiveness of bio-organic fertilization in enhancing wheat growth, yield, grain Zn biofortification, and soil fertility under deficient arid field conditions. Two field trials were conducted in Bahawalpur and Bahawalnagar, Pakistan, using a randomized complete block design. Treatments included compost, ZnO (2 %), ZnSO_4, zinc-solubilizing bacteria (ZSB), and their combinations. Wheat growth, yield, grain nutrient concentrations, and soil fertility indicators (organic matter, microbial biomass nitrogen (MBN), microbial biomass carbon (MBC), and nutrient availability) were measured. Microbial populations were determined through colony-forming units. Correlation and principal component analysis (PCA) were applied to explore associations among variables. The integrated application of compost + ZnO + ZSB significantly improved wheat height (19 %), biomass (20 %), yield attributes (10 %), and grain Zn concentration (39 %) compared with the control. Soil fertility parameters also increased (organic matter, 39 %; MBN, 32 %; MBC, 27 %). Correlation and PCA highlighted strong positive relationships among microbial populations, soil fertility, and crop performance. Bio-organic fertilization provides an eco-friendly and effective strategy to improve wheat yield, Zn biofortification, and soil fertility in arid agroecosystems.