Open access peer-reviewed chapter

Fungal Growth and Pathology

Written By

Ozlem Gulmez and Ozlem Baris

Submitted: 29 August 2021 Reviewed: 07 February 2022 Published: 06 March 2022

DOI: 10.5772/intechopen.103109

From the Edited Volume

Fungal Reproduction and Growth

Edited by Sadia Sultan and Gurmeet Kaur Surindar Singh

Chapter metrics overview

603 Chapter Downloads

View Full Metrics


Fungi, an important group with a wide variety of species, shows spectacular development with their unique cell structures. Fungi survive in many different ecosystems with their reproductive abilities and metabolic features. Thanks to wide temperature and pH tolerances, fungi develop on organic and inorganic materials in all ecosystems they are in and maintain the existence of ecosystems by taking part in many cycles. However, examples of pathogens are also available. They are a group of organisms that are environmentally important, such as saprophytes and mutualists, but are pathogens for animals, especially plants. Fungi basically have two different cell structures: yeast, and molds. But some fungi have both of these structures. Depending on the temperature of the environment they are in, they can be found in yeast or mold structures, and fungi with this feature are called dimorphic fungi. Whether it is yeast, mold, or dimorphic fungi, they use their enzymes with high activity to benefit from the nutrients in the environment. Fungi can be easily grown in natural and synthetic media. Yeast can reproduce rapidly with their single-celled structure, while molds and mushrooms are very successful with their hyphae structures.


  • fungal growth
  • pathology
  • reproduction

1. Introduction

Fungi are eukaryotic organisms thought to have about 4 million species [1]. Although the cell structures of fungi are similar to other eukaryotic cells, they differ from other cells by the presence of ergosterol in their cell membrane and chitin in their cell walls. Cell cytoplasm contains higher concentrations of salt and sugar than other eukaryotes. This regulates cell homeostasis and regulates the exchange of substances. Except for yeasts, most fungi have microscopic structures called hyphae, and these come together to form visible structures called mycelium. The hyphae have apical growth. In the apical growing parts of the hyphae, there are secretory vesicles called “Spitzenkörper” and Wooronin body organs that act as peroxisomes. Because of these properties of hyphae, fungi can live where other eukaryotic cells do not and can use various substrates [2, 3]. Fungi take part in many degradations, transformation, and cycle events in nature. Although they are heterotrophic creatures, they can survive as saprophytic, mutualistic, and parasitic. The fact, that they are found in all parts of the world and live in different environments is due to the superior reproductive abilities of fungi [4, 5, 6].

1.1 Fungal reproduction

Fungi can reproduce sexually and asexually. Asexual reproduction of fungi is carried out by vegetative reproduction through hyphae or by the spores they produce. Sexual reproduction is; they form a diploid nucleus with the union of haploid spores, and the cycle continues with the germination of this nucleus. In fungi, asexual reproduction takes place more than sexual reproduction. This event increases the adaptive power of fungi and prevents the accumulation of any harmful mutations that may occur and their transmission from generation to generation. In addition, their chances of survival and competitive advantage are ensured [4, 5, 7].

Sexual reproduction in fungi takes place in three stages. In the first stage; haploid cells fuse, this is called plasmogamy. In the second stage; the fusion of two haploid nuclei, this event is karyogamy. The third stage is; the resulting diploid cells undergo meiosis to form haploid cells, and the cycle continues in this way [8]. These stages are summarized in Figure 1.

Figure 1.

Fungal reproduction.

The association or non-union of haploid cells is determined by DNA. The sex of haploid cells is determined by a specific gene region in fungi. This region is known as the mating-type locus and is abbreviated MAT. MATs genetically determine the mating identity of fungi and stimulate the secretion of pheromones. Secreted pheromones provide communication between fungi and realize sexual intercourse [4, 9, 10, 11].

1.2 Growth and development needs of fungi

Fungi, like every living thing, need energy and food sources to complete their development and life cycles after sexual and asexual reproduction. These food sources are carbon, nitrogen, vitamins, and minerals. They also need suitable environmental conditions (such as pH, temperature, humidity, oxygen) to grow and develop [12, 13, 14].

Fungi can consume vegetable and animal carbon sources thanks to their hydrolytic enzymes. They can use monosaccharides and polysaccharides such as glucose, fructose, chitin, cellulose, hemicellulose, and lignin [15, 16]. Like all living things, fungi need a nitrogen source for their growth and development, and fungi can metabolize many different nitrogen sources. Especially ammonium and glutamine are the first nitrogen sources they use. In addition, they can easily use other nitrogen sources [17].

Vitamins are cofactors of enzymes and growth factors of many organisms. Fungi need vitamins for their growth and development. Some of these vitamins are; thiamine, biotin, riboflavin, nicotinic acid, vitamin K and pantothenic acid [18].

Like many microorganisms, fungi can survive in varying environmental conditions and under various stress factors. They can survive and reproduce in extreme environments, such as the poles, in extremely cold regions, and in extremely hot regions such as deserts. Fungi are generally; grow better in warm, acidic, and aerobic environments, but they can survive in cold, alkaline, and anaerobic environments. Although the growth temperatures of the fungi are quite wide, the best growth is seen at 25°C. Fungi that live under the temperature at which they develop optimally are called psychrotolerant, and fungi that live at temperatures of 40°C and above are called thermotolerant fungi. Fungi that live in or are exposed to temperatures above 40°C can survive by protecting themselves from heat stress by producing heat shock proteins. Fungi can be found in yeast or mold structures depending on the temperature of the environment they are in, and fungi with this feature are called dimorphic fungi. One of the most important fungi showing this feature is Histoplasma sp. If the place where it is located in an environment of 25°C, it develops as a mold with a hyphae structure that can reproduce vegetatively, and as yeast if the environment is 37°C. This feature allows them to survive in different ecosystems and even to continue their generation [19]. The pH value, which is important for the realization of many biochemical reactions in all living things, is one of the important environmental conditions for fungi. Some fungi can survive and even reproduce at pH 1 and 13, which are extreme for many organisms. Most fungi survive and reproduce between pH 3 and 10. The optimum pH range is between 5 and 7 [20, 21, 22]. In addition, if the environment in which fungi are found in alkaline, they can achieve maximum growth by converting the pH of the environment to the optimum growth pH with the organic acids they secrete. Abiotic stress factors such as water, UV, and heavy metals affect the development of fungi as well as all organisms. In particular, UV-B radiation, which is more biologically harmful, negatively affects the growth and development of fungi [23].

Fungi are among the largest and most diverse groups of eukaryotic organisms. Because of their complex gene structure, the enzymes they produce, and their ability to use many different carbon sources, they, directly and indirectly, affect human life. They have been used for centuries as a food source and in the production process of many biotechnological products. Today, fungi are used in various fields such as antibiotics, enzyme technology, drug production, pigment production [24, 25, 26]. Although fungi are necessary for the survival of life on earth, they cause serious problems in most organisms. Fungi cause disease in humans, animals, and plants and cause the death of these organisms [27, 28]. Fungi infect many organisms with the secondary metabolites and mycotoxins they produce, even cause their extinction [29].

1.3 Pathogenic fungi

A fungal kingdom is a group that contains the most and most harmful plant pathogens. By infecting all tissues and organs of plants, they damage many herbaceous and woody plants with high economic value and nutritional properties. In cultivated plants such as corn, wheat, sugar beet, potato, banana; causes great harm to farmers by causing diseases such as root rot, wilt, stem softness, gall and rust. They also develop in stored grains and cause product loss. Also; high woody plants are infected by white rot and brown rot fungi, resulting in tissue deterioration and plant death. Plant pathogen fungi can reproduce both sexually and asexually in host plants [30, 31, 32, 33]. Table 1 shows the plants that some fungi cause disease.

Pathogen fungusPlantDamage
Heterobasidion parviporumPiceaRoot rot
Heterobasidion annosumAbiesRoot rot
Ustilago maydisMaizeGall
Sporisorium reilianumMaize, Sugar beetEar rot
Puccinia graminis f. sp. triticiWheat, barleyBlack rust
Melampsora liniFlaxseedRed rust
Fusarium oxysporiumTomato, pepper, watermelonRoot rot
Alternaria sp.Chickpeas, carrots, olives, applesPallidness
Apergillus nigerGingerAflatoxin
Leptosphaeria maculansCrucifersBlackleg
Podosphaera plantaginisBananaMildew
Rhizoctonia solaniSoybeanRoot rot
Dothistroma septosporumPinusRed band needle blight
Lecanosticta acicolaPinusBrown spot needle blight,
Phytophthora infestansTomato, potato, pepper eggplantMildew
Verticilum sp.PlantsVascular pallor

Table 1.

Some plant pathogenic fungi and infecting plants.

Fungi cause infections not only in plants but also in humans and animals. Bees, insects, frogs, fish, and corals are some organisms affected by fungal infections. Fungi enter the body from the outer shells, trachea, and skin of these creatures and cause the death of these creatures. Fungal diseases have killed more than 1.6 million people annually. It is thought that pandemics caused by fungi may occur with global warming and climate change [34]. Because the stress tolerance and adaptation abilities of the fungi are very high, they have destroyed their existence on earth by infecting many different organism groups (Table 2). In humans, they cause skin infection, lung infection, and intestinal infection. They also cause diseases in animals and humans by reproducing sexually and asexually [35, 36].

Pathogen fungusOrganismsDamage
Fusarium sp.HorseEncephalomalacia
Aspergillus sp.HumanLiver cancer
Cladophialophora bantianaHumanBrain tissue loss
Candida aurisHumanInfection in the blood
Cryptococcus sp.HumanInfection in the lung
Batrachochytrium dendrobatidisAmphibian
Laboulbenia formicarumAnt
Aspergillus fumigatusBirdLung infection
Fusarium, Ochroconis, Exophiala, Scytalidium, Plectosporium, and Acremonium.Fish
Microsporum canis and Sporothrix brasiliensisCat

Table 2.

Diseases are caused by some pathogenic fungi in humans and animals.


2. Conclusions

Apart from its use as food; the fungi which we use in the production of drugs, antibiotics, anticarcinogenic substances, pigments, alcohol, and biofuels, are indispensable elements for the continuation of our lives. As we stated in this publication, their high reproductive capacity and ability to survive in extreme conditions provide fungi with a competitive advantage and advantage over other organisms. These abilities give it the capability to live in the plant, animal, and human tissue-organs. If the development and growth demand of fungi, whether pathogenic or not, are known, we can make the most of these organisms and prevent the development of fungi that cause disease. This study will enable us to get to know fungi a little more closely and will enable us to take precautions against these organisms.


Conflict of interest

The authors do not declare any conflict of interest.


  1. 1. Nilsson RH, Larsson KH, Taylor AFS, Bengtsson-Palme J, Jeppesen TS, Schigel D, et al. The UNITE database for molecular identification of fungi: Handling dark taxa and parallel taxonomic classifications. Nucleic Acids Research. 2019;47(D1):D259-D264
  2. 2. Money NP. Fungi and biotechnology. In: The Fungi. Oxford, OH, USA: Academic Press; 2016. pp. 401-424
  3. 3. Raghukumar S. Fungi: Characteristics and classification. In: Fungi in Coastal and Oceanic Marine Ecosystems. Cham: Springer; 2017. pp. 1-15
  4. 4. Peraza-Reyes L, Malagnac F. 16 sexual development in Fungi. In: Growth, Differentiation and Sexuality. Cham: Springer; 2016. pp. 407-455
  5. 5. Dyer PS, Inderbitzin P, Debuchy R. 14 mating-type structure, function, regulation and evolution in the pezizomycotina. In: Growth, Differentiation and Sexuality. Cham: Springer; 2016. pp. 351-385
  6. 6. Li D, Tang Y, Lin J, Cai W. Methods for genetic transformation of filamentous fungi. Microbial Cell Factories. 2017;16(1):1-13
  7. 7. Döll K, Chatterjee S, Scheu S, Karlovsk P, Rohlfs M. Fungal metabolic plasticity and sexual development mediate induced resistance to arthropod fungivory. Proceedings of the Royal Society B: Biological Sciences. 2013;280(1771):20131219
  8. 8. Wallen RM, Perlin MH. An overview of the function and maintenance of sexual reproduction in dikaryotic fungi. Frontiers in Microbiology. 2018;9:503
  9. 9. Lee SC, Heitman J. Sex in the Mucoralean fungi. Mycoses. 2014;57:18-24
  10. 10. Ni M, Feretzaki M, Sun S, Wang X, Heitman J. Sex in fungi. Annual Review of Genetics. 2011;45:405-430
  11. 11. Nieuwenhuis BP, Billiard S, Vuilleumier S, Petit E, Hood ME, Giraud T. Evolution of uni-and bifactorial sexual compatibility systems in fungi. Heredity. 2013;111(6):445-455
  12. 12. Basu S, Bose C, Ojha N, Das N, Das J, Pal M, et al. Evolution of bacterial and fungal growth media. Bioinformation. 2015;11(4):182
  13. 13. Wongjiratthiti A, Yottakot S. Utilization of local crops as alternative media for fungal growth. Pertanika Journal of Tropical Agricultural Science. 2017;40:295-304
  14. 14. Sawiphak S, Wongjiratthiti A, Saengprasan C. Dioscorea alata as alternative culture media for fungal cultivation and biomass production. Pertanika Journal of Tropical Agricultural Science. 2021;44(2):327, 336
  15. 15. Homaei A, Ghanbarzadeh M, Monsef F. Biochemical features and kinetic properties of α-amylases from marine organisms. International Journal of Biological Macromolecules. 2016;83:306-314
  16. 16. Pawłowska J, Okrasińska A, Kisło K, Aleksandrzak-Piekarczyk T, Szatraj K, Dolatabadi S, et al. Carbon assimilation profiles of mucoralean fungi show their metabolic versatility. Scientific Reports. 2019;9(1):1-8
  17. 17. Tudzynski B. Nitrogen regulation of fungal secondary metabolism in fungi. Frontiers in Microbiology. 2014;5:656
  18. 18. Tanner RS. Cultivation of bacteria and fungi. In: Manual of Environmental Microbiology. Third ed. Wasington, DC, USA: American Society of Microbiology; 2007. pp. 69-78
  19. 19. Rodriguez L, Voorhies M, Gilmore S, Beyhan S, Myint A, Sil A. Opposing signaling pathways regulate morphology in response to temperature in the fungal pathogen Histoplasma capsulatum. PLoS Biology. 2019;17(9):e3000168
  20. 20. Peñalva MA, Tilburn J, Bignell E, Arst HN Jr. Ambient pH gene regulation in fungi: Making connections. Trends in Microbiology. 2008;16(6):291-300
  21. 21. Zhang L, Song X, Shao X, Wu Y, Zhang X, Wang S, et al. Lead immobilization assisted by fungal decomposition of organophosphate under various pH values. Scientific Reports. 2019;9(1):1-9
  22. 22. Alves TP, Triques CC, da Silva EA, Fagundes-Klen MR, SDM H. Multi-enzymatic recovery of fungal cellulases (Aspergillus niger) through solid-state fermentation of sugarcane bagasse. The Canadian Journal of Chemical Engineering. 2021;1:11. DOI: 10.1002/cjce.24292
  23. 23. Hughes KA, Lawley B, Newsha KK. Solar UV-B radiation inhibits the growth of Antarctic terrestrial fungi. Applied and Environmental Microbiology. 2003;69(3):1488-1491
  24. 24. Solomon L, Tomii VP, Dick AAA. Importance of fungi in the petroleum, agro-allied, agriculture and pharmaceutical industries. New York Science Journal. 2019;12:8-15
  25. 25. Li Y, Jin W, Mu C, Cheng Y, Zh W. Indigenously associated methanogens intensified the metabolism in hydrogenosomes of anaerobic fungi with xylose as substrate. Journal of Basic Microbiology. 2017;57(11):933-940
  26. 26. Matassa S, Boon N, Pikaa I, Verstraet W. Microbial protein: Future sustainable food supply route with low environmental footprint. Microbial Biotechnology. 2016;9(5):568-575
  27. 27. Hyde KD, Norphanphou C, Chen J, Dissanayake AJ, Doilom M, Hongsanan S, et al. Thailand’s amazing diversity: Up to 96% of fungi in northern Thailand may be novel. Fungal Diversity. 2018;93(1):215-239
  28. 28. Hyde KD, Tennakoon DS, Jeewon R, Bhat DJ, Maharachchikumbura SS, Rossi W, et al. Fungal diversity notes 1036-1150: Taxonomic and phylogenetic contributions on genera and species of fungal taxa. Fungal Diversity. 2019;96(1):1-242
  29. 29. Gruber-Dorninger C, Jenkins T, Schatzmayr G. Global mycotoxin occurrence in feed: A ten-year survey. Toxins. 2019;11(7):375
  30. 30. Javelle M, Vernoud V, Rogowsky PM, Ingram GC. Epidermis: The formation and functions of a fundamental plant tissue. New Phytologist. 2011;189(1):17-39
  31. 31. Menardo F, Praz CR, Wyder S, Ben-David R, Bourras S, Matsumae H, et al. Hybridization of powdery mildew strains gives rise to pathogens on novel agricultural crop species. Nature Genetics. 2016;48(2):201-205
  32. 32. Möller M, Stukenbrock EH. Evolution and genome architecture in fungal plant pathogens. Nature Reviews Microbiology. 2017;15(12):756-771
  33. 33. Casadevall A. Don't forget the fungi when considering global catastrophic biorisks. Health Security. 2017;15(4):341-342
  34. 34. Gostinčar C, Zajc J, Lenassi M, Plemenitaš A, De Hoog S, Al-Hatmi AM, et al. Fungi between extremotolerance and opportunistic pathogenicity on humans. Fungal Diversity. 2018;93(1):195-213
  35. 35. Seyedmousavi S, Bosco SDM, De Hoog S, Ebel F, Elad D, Gomes RR, et al. Fungal infections in animals: A patchwork of different situations. Medical Mycology. 2018;56(suppl_1):S165-S187
  36. 36. Almeida F, Rodrigues ML, Coelho C. The still underestimated problem of fungal diseases worldwide. Frontiers in Microbiology. 2019;10:214

Written By

Ozlem Gulmez and Ozlem Baris

Submitted: 29 August 2021 Reviewed: 07 February 2022 Published: 06 March 2022