ECOLOGICAL IMPORTANCE OF FUNGI

DR VISHNUPRIYA SHARMA

WHAT ARE THE FUNGI ?

Achlorophyllous, Eukaryotic,heterotrophs, thallophytes.

Cosmopolitan in distribution.

Microscopic to macroscopic in nature.

Cannot synthesize their own food, unlikegreen plants.

Dependent for their food on some livingsubstratum(parasite) or on dead organicmaterial(saprophyte).

Aristotle, Haeckel, Copeland gave initial classifications.

Comprising the mushrooms, molds, mildews,smuts,rusts, and yeasts, and classified in the kingdom Fungi (Whittakar).

Later Alexopolous, Ainsworth et al have classified entirefungi into 2 subdivisions.

According to scientists, there are approximately 1.5million species of fungi n the planet but only some percentof them have been given proper identification.

BIODIVERSITY

Defined as variety and variability of shape,size and form

It includes

Genetic diversity ( genes, chromosomes),

Taxonomic diversity ( species, genus,families) and

Biogeographic diversity (habitats,landscapes, ecosystem).

MACROFORMS COLLECTED FROM PARADE GROUND ALLAHABAD

Auricularia polytricha Polyporus sp. P.alveolaris

Coral fungi Ganoderma tsugae Taloromyces chinensis

RANGE OF STRUCTURE OF FUNGI-Unicellular yeast, filamentous and microscopic molds like blue green mold, black

mold, macroscopic mushrooms, wood rotting fungi.

DIVERSITY OF FUNGI - Most diversified in their habitat and are found in allpossible habitat.

ECOLOGICAL ROLE OF FUNGI-IN A FOOD CHAIN

Fungi being saprotrophs play a role in theprocess of decomposition of dead remains ofother organisms eg dead animal bodies, deadherbaceous or woody plants or waste productslike fecal matter, fallen leaves or dead woodpieces. Fungi break down the dead organicmatter and return vital nutrients on the soil.Without fungi, nutrients would not be cycledthrough ecosystem leading to breakdown offood chain.

ECOLOGICAL IMPORTANCE AS NATURALSWEEPERS OR REDUCERS OF ECOSYSTEM

Fungi as Decomposers

Fungi join bacteria as the primary decomposers in different ecosystems. They feedon the organic remains of dead plants. They release special enzymes that breakdown lignin, a structurally complex substance in wood. Because of their ability tobreak down wood, fungi are considered the major wood decomposers in forests.To absorb organic matter, fungi release acids to melt organic matter, and then theysuck the acid back together with the melted organic matter. Decomposing organicmatter is considered by ecologists as the major ecological role of fungi.

ECOLOGICAL ROLE OF FUNGI AS MYCORRHIZA ASYMBIOTIC RELATIONSHIP

Association between a vascular plant root and fungi is calledmycorrhiza as fungi colonize the roots of a plant, build aconnection to the roots and exchange nutrients with each other.Plants provide mycorrhizal fungi shelter and a supply ofcarbohydrates; in return, mycorrhizal fungi improve the plant’sabsorption capabilities for water and nutrients because they havea larger surface-area ratio compared to roots, so they have higherabsorptive capacity for water and minerals. They make it easierfor plants to absorb water and minerals in soils that are dry andwith low mineral concentration about 90% of plants are dependson mycorrhizal fungi for survival.

ENDOMYCORRHIZA AS BIOFERTILIZERGerman pathologist AB Frank (1885) coined the termmycorrhizae.

VAM- Vesicular Arbuscular Mycorrhizae are some fungiwhich penetrates the root cells by means of projectionsand develop intercellularly, forms intercellular branchedstructures called as arbuscules helpful in phosphatenutrition of plants.

Compost as bio fertilizer- Crop residue, cow dung, cattledung, farm waste and animal urine is degraded byseveral species of fungi like Aspergillus, Tricoderma and

Penicillium, as these are the efficient cellulolytic culturesused for the formation of compost

FUNGUS AS AN COMPONENT OF LICHENS-THE PIONEERS OF SUCCESSION

Lichens are the distinct group of plants having acomposite structure consisting of two dissimilarorganisms – A Fungus and an algae associatedin an symbiotic union.

Lichens are considered to be the pioneers ininitiating a xerach succession on rocks. Theyinitiate the weathering of rocks into soilparticles thus are called as soil builders.

Lichens are highly sensitive to sulphur dioxidepollution as a significant indicator of air pollution.

FUNGAL ORGANISMS AS ENVIRONMENTALCLEANERS- BIODEGRADATION.

Bioremediation (biological remediation) is the use of biological agents to clean and

restore a polluted environment.

Few fungal species of are able to degrade soil pollutants such as insecticides,

herbicides, heavy metals, creosote, coal tars, and hydrocarbon fuels. (eg P.

crysogenum , M. plumbens, T. virideae are able to metabolize pesticides by

secreting enzymes that neutralize the Xenobiotics( man made products eg

pesticides)

BENEFICIAL ROLE OF FUNGI- FOOD VALUE

Fungi as food- mushrooms , morels, truffels, tubers, Agaricus compestris,

Bakers Yeast- Saccharomyces cerevisae Used in bakery, breweries andproduction of wine, beer, rum

A SOURCE OF MEDICINE AND ANTIBIOTICS

Antibiotics are defined as substances of biological origin which at lowconcentration can inhibit the growth of bacteria.

Claviceps purpurea produces alkaloides like ergotamine which is used to induceuterine contractions, check haemorrhage, treatment of head ache , migraine.

Natural source of LSD (Lysergic acid diethylamide) a modern medicine used inexperimental psychiatry.

HARMFUL EFFECTS OFFUNGI

Diseases of plants.

Diseases of humans as aspergillosis,ringworm, ear infection.

Destruction of wood.

Spoilage of food.

Destruction of common goods likeleather, paper by penicillium, mucorand Chaetomium.

Acknowledgement

Special thanks for Ms Justyna Malec for taking pictures form natural habitat inWojcechowka, Tyszowce Poland in months of September and october 2017 andsharing them with this presentation.

Thank you