Livestock’s Urine-Based Plant Microbial Fuel Cells Improve Plant Growth and Power Generation

Abstract

Plant microbial fuel cells (P-MFCs) are sustainable and eco-friendly technologies, which use plant root exudates to directly nourish the electrochemically active bacteria (EABs) to generate sustainable electricity. However, their use in evaluating plant growth has been insufficiently studied. In this study, interconnection between plant growth and the production of bioelectricity was evaluated by using P-MFCs inoculated with 642.865 mL ≅ 643 mL of livestock’s urine such as cow urine, goat urine, and sheep urine. The greatest mean stem diameter of 0.52 ± 0.01 cm was found in P-MFC-3 inoculated with goat urine, while the P-MFC-2 treated with cow urine reached a higher average number of roots with a value of 86 ± 2.50 (95% improvement) (p < 0.05). Besides, P-MFC-4 presented greater height of 50.08 ± 0.67 cm. For polarization curve experiment a higher maximum power density of 132 ± 11.6 mW m−2 (931 mA m−2) was reached with cow urine; in turn, with regard to the long-term operation, the same reactor indicated a higher maximum average power density of 43.68 ± 3.05 mW m−2. The study’s findings indicated that Stevia P-MFC inoculated with urine was a good option to increase the biomass amount for the agricultural plants along with power generation. Further, this study opens the way for more investigation of evaluating the impact of P-MFC on plant growth.

Effect of Plants Morphological Parameters on Plant-Microbial Fuel Cell Efficiency

“…PMFCs based on well-known low-growing plants, such as succulents Opuntia or water lettuce Pistia stratiotes or plants with poorly developed root systems such as water spinach Ipomea aquatica [17,19], were characterized by lower power, 6.07 and 3.54-6.35 mW m 2 , respectively, than PMFC based on plants with more developed roots and green biomass such as Vigna ungiculata ssp. sesquipedalis, 160.86 mW m 2 [38] or Stevia rebaudiana, 66-132 mW m 2 [29,39].…”

“…Alisma plantago-aquatica, Festuca arundinacea, Сarex hirta, Ocimum basilicum plant and Polytrichum commune moss were chosen as plants that showed promising results in terms of bioelec-tricity generation in our previous experiments. The study of the relationship between the generation of electricity and morphological features of the plant, such as the length of the stems, the number of leaves and defoliation, the length and number of roots, the diameter of the stems is only beginning to be studied [25,28,29]. Denser developed root system and high plant biomass considered as advantageous to power production and signs of highly efficient PMFC [27,30].…”

Revitalizing Agriculture: Role of Cow Dung and Urine in Promoting Sustainability

“…These PGPBs are beneficial microorganisms that can help to improve plant growth by increasing nutrient availability, reducing stress and protecting against pathogens (Anandham et al, 2015). The PGPB found in cow urine includes bacteria such as Bacillus, Pseudomonas and Azospirillum (Apollon et al, 2022). These bacteria can help to promote plant growth in several ways.…”