Fungal Networks — Soil Environment and Fungi
The interactions between microorganisms in soil are like a complex tapestry. The actions of single microorganisms, as well as their group actions and interactions between species, all play a part in the complex dynamics of the soil environment. This intricate web of interactions encompasses the formation of fungal networks, including several species of fungi. These interactions shed light on the nuanced relationships between specific microbe species, including the role of Effective Microorganisms in bokashi.
At an individual level, microbes in the soil, such as specific bacteria like Bacillus and Lactobacillus, photosynthetic bacteria, yeasts, and fungi like Trichoderma, function as pivotal players in nutrient cycling, organic matter decomposition, and other vital processes. These individual microbial species produce enzymes and metabolic byproducts (metabolites) that collectively shape the chemical and physical properties of the soil, influencing its overall health and fertility. Trichoderma controls many pathogenic fungi and is considered a beneficial fungus. Studies have been conducted on the relationship of Trichoderma with other beneficial microbes, including a 1991 study by Higa and Wididana. The study looks at the effects of different formulas of Effective Microorganisms (EM2, EM3, EM4, and EM-1) and their effects on soils and other fungi in the soil, including Fusarium, Penicillium, Thielvaviopsis, Trichoderma, and Verticillium. “The effect of EM on fungal populations in soil (Table 3 below) indicated that soil treated with only fertilizer had low numbers of Penicillium and Trichoderma. These beneficial fungi can be important in inhibiting or suppressing soil-borne microbial plant pathogens through their antagonistic activities.” (Higa and Wididana, 1991)
Microbes form diverse microbial communities that engage in symbiotic or competitive relationships. Almammory et al. conducted a detailed study published in 2019. They reviewed Trichoderma, Bokashi, and salicylic acid (SA). SA was used as a biostimulant as it increases hydrogen peroxide production and the enzyme peroxidase. “Рeroxidases play an important role in innate immunity and in a number of physiologically important processes like apoptosis and cell signaling.” (Vlasova, 2018) They tested each material’s ability to control three different soil pathogens and used combinations of each (for example, Bokashi + Trichoderma; Trichoderma + SA; SA + Bokashi; Bokashi + SA + Trichoderma). The researchers saw that the biofertilizer Bokashi and salicylic acid worked better together to kill pathogenic fungi than the control group that was not treated. Specifically, they detected “a significant improvement in the treatment of interference between T. harzianum and bio-fertilizer Bokashi and salicylic acid, with the highest result in the length of the plant.” (Almammory et al., 2019) Finally, the combination of all three performed the best. The combination of bokashi, a product made with mixed bacteria and yeast, worked synergistically with Trichoderma harzianum, showing a great synergy between bacteria and a fungus.
Interactions between microbial species, such as bacteria and fungi, showcase a fascinating interplay. Specific bacteria, like those from the Bacillus and Lactobacillus genera, release compounds that promote the growth of fungi, while others, such as Pseudomonas, produce antibiotics that inhibit fungal growth. This delicate balance is vital for maintaining a diverse and stable microbial community within the soil. It also appears that these relationships appear to be species-specific, such as the relationships between “Gigaspora margarita spores and the following bacteria: Flexibacter (Bacteroidetes), Cyanobacteria, Fibrobacteres, Burkholderia, Cellvibrio, Chondromyces, Desulfovibrio, Lysobacter, Pseudomonas, Rheinheimera (Proteobacteria), Paenibacillus polymyxa (Firmicutes), and Janthinobacterium lividum (Proteobacteria)” (Ujvári et al., 2021)
In the realm of mycorrhizal associations, fungi like Glomus form networks that connect with plant roots, facilitating nutrient exchange. Both ectophytes and endophytes enhance soil fertility and promote plant health while providing nutrients to the fungi in the soil. “Effective Microorganisms [EM] enhances the activities of beneficial indigenous microorganisms, for example, mycorrhizae (ecto as well as endomycorrhizae), which fix atmospheric nitrogen and accelerate phosphorus and zinc uptake from soil, thereby supplementing the use of chemical fertiliser and pesticides.” (Joshi et al., 2019) These microorganisms contribute to the overall well-being of the plant-soil system through their synergistic interactions.
Understanding the specific roles of microbial species is paramount for sustainable agriculture and ecosystem health. It underscores the importance of promoting microbial diversity and maintaining a balanced microbial community in the soil. By delving into the intricacies of individual and collective microbial functions, we gain valuable insights into the resilience and productivity of soil ecosystems, informing enlightened agricultural practices and environmental stewardship.
References
Ali, H. Z., & Nadarajah, K. (2013). Evaluating the efficacy of Trichoderma isolates and Bacillus subtilis as biological control agents against Rhizoctonia solani. Research Journal of Applied Sciences, 8(1), 72-81.
Almammory, M. K., & Matloob, A. A. (2019). Efficiency of Trichoderma harzianum and Bio-Fertilizer Bokashi and Salicylic acid to control of fungi causing Eggplant Damping off Disease. Plant Archives, 19(1), 73-82.
Higa, T., & Wididana, G. N. (1991). Changes in the soil microflora induced by effective microorganisms. In Proceedings of the First International Conference on Kyusei Nature Farming. US Department of Agriculture, Washington, DC, USA (pp. 153-162).
Joshi, H., Somduttand, C. P., & Mundra, S. L. (2019). Role of effective microorganisms (EM) in sustainable agriculture. International Journal of Current Microbiology and Applied Sciences, 8(3), 172-181.
Vlasova, I. I. (2018). Peroxidase Activity of Human Hemoproteins: Keeping the Fire under Control. Molecules : A Journal of Synthetic Chemistry and Natural Product Chemistry, 23(10). https://doi.org/10.3390/molecules23102561
Thanks, Randy!
This post is an excerpt from an upcoming book I am co-writing on Bokashi. My co-writer and I keep running into more and more details to explore and expand upon. Writing this book is like building a puzzle without being able to see the pieces. The final picture keeps morphing and appearing as we build the story. It is a fascinating journey!
Great piece! Thanks for sharing this important information with us.