Biogenic Nano-Fertilizers as a Sustainable Approach to Alleviate Nitrate Accumulation and Enrich Quality Traits of Vegetable Crops

Vegetables accumulate considerable amounts of nitrates that enter the human body through nutrition, causing severe problems. This study aims to determine celery plants' response to replacing mineral nitrogen fertilizers with bio-nanoparticles. Three different treatments of nano bio-nitrogen fertilizer (20, 30, and 40 ppm) in addition to traditional nitrogen (NH4NO3) treatment (100 kg N/acre) were applied on two celery cultivars (Balady and Utah Tall 52-75). Plant growth parameters, vitamin C, carotenoids, nitrate accumulation, macro-nutrient uptakes, and antioxidant activities were determined at the vegetative marketing stage. Our findings reveal a significant positive impact of replacing conventional nitrogen fertilizers with bio-nano-synthesized forms. Notably, applying bio-nanoparticles improved celery yield efficiency, ranging from 5.1 to 5.8 tons per acre, suggesting a viable alternative to traditional fertilization methods. Furthermore, transitioning from mineral to organic fertilizers in nanoparticle form reduced nitrate accumulation in fresh celery crops, decreasing nitrate levels from 342.5 ppm to as low as 100 ppm. This environmentally conscious approach offers a sustainable solution to mitigate chemical residues and enhance celery's flavor, nutritional value, and health benefits. Specifically, our results demonstrate alleviated nitrate contents in fresh celery leaves after applying bio-nano-fertilizer. Nitrate levels in treated plants decreased by up to 70.0% compared to traditional fertilization methods. This highlights the potential of organic nano-fertilizers to address concerns related to nitrate accumulation, thereby promoting safer and healthier vegetable consumption. By advocating for organic nano-fertilizers, we propose a promising strategy to optimize celery fertilizing management, ensuring sustainable farming and consumer well-being.