Funneliformis mosseae Application Improves the Oil Quantity and Quality and Eco-physiological Characteristics of Soybean (Glycine max L.) Under Water Stress Conditions

The water deficit is one of the main limiting abiotic stress factors affecting the plant physiology, growth, and productivity. The aim of the present study was to evaluate the impact of bio-fertilizer application under water stress conditions on the soybean productivity and its oil quality as a new strategy in sustainable agriculture. The experimental treatments included different water irrigation regimes including irrigation after 20% (W-20, well-watered conditions), 50% (W-50, moderate water deficit), and 80% (W-80, severe water deficit) soil water depletion, as well as inoculation and non-inoculation of arbuscular mycorrhizal fungus (AMF). The results demonstrated that the seed yield, oil productivity, and oil yield of soybean decreased in moderate and severe water stress conditions. The maximum protein content (43.83%) was obtained in W-50 water stress treated with AMF. AMF inoculation enhanced the seed and oil yields by 22.7 and 20.1% in comparison with control, respectively. In addition, the activity of antioxidant enzymes increased in water stress conditions treated with AMF. AMF inoculation improved the soybean oil quality as shown by the higher content of unsaturated fatty acids such as oleic and linoleic acids and lower content of saturated fatty acids such as palmitic and stearic acids. Application of AMF could be recommended as an eco-friendly strategy for improving soybean oil quality and quantity under water deficit conditions.