Syllabus | MICROBIAL ECOLOGY AND PLANT PATHOLOGY | Second Year | B.Sc Microbiology

SUBJECT: MICROBIAL ECOLOGY AND PLANT PATHOLOGY

S.no

Topic

Domain

Hours

1

Microorganisms habitat and their role in biogeochemical cycles and succession pattern

Terrestrial Environment: Soil microflora. Aquatic Environment: Stratification & Microflora of Freshwater & Marine habitats .
Atmosphere: Stratification of the Atmosphere, Aeromicroflora, Dispersal of Microbes .Animal Environment: Microbes in/on human body (Microbiomics) & animal (ruminants) body.  Extreme Habitats: Extremophiles: Microbes thriving at high & low temperatures, pH, high hydrostatic & osmotic pressures, salinity, & low nutrient levels.

Must know

10

Carbon cycle: Nitrogen cycle Ammonification, nitrification, denitrification & nitrate reduction. Phosphorous cycle: Phosphate immobilization and phosphate solubilization. Sulphur Cycle Microbes involved in sulphur cycle.

Desirable to know

8

Succession of microbial communities in the decomposition of plant organic matter

Nice to know

2

2

Microbe–Microbe Interactions
Mutualism, Synergism, Commensalism, Competition, Amensalism, Parasitism, Predation, Biocontrol agents

Must know

10

Microbe–Plant Interactions:  Roots, Aerial Plant surfaces, Biological Nitrogen fixation (symbiotic/nonsymbiotic- biofertilizers)

Desirable to know

5

Microbe–Animal Interactions : Role of Microbes in Ruminants, Nematophagus fungi, Luminescent bacteria as symbiont

Nice to know

5

3

Microbial Pathogenicity : Virulence factors of pathogens: enzymes, toxins (host specific and non specific) growth regulators, virulence factors in viruses (replicase, coat protein, silencing suppressors) in disease development.

Must know

8

Effects of pathogens on host physiological processes (photosynthesis, respiration, cell membrane permeability, translocation of water and nutrients, plant growth and reproduction).

Desirable to know

7

Genetics of Plant Diseases : Concept of resistance (R) gene and avirulence (avr) gene; Gene for gene hypothesis, types of plant resistance: true resistance– horizontal & vertical, apparent resistance.

Nice to know

5

4

Concept of plant disease- microbial plant diseases, types of plant pathogens, pathogenicity, symptoms, economic losses. Principles & practices involved in the management of plant diseases by different methods

Must know

10

Important diseases caused by fungi
White rust of crucifers – Albugo candida
Downy mildew of onion – Peronospora destructor
Late blight of potato – Phytophthora infestans
Powdery mildew of wheat – Erysiphe graminis
Ergot of rye – Claviceps purpurea
Black stem rust of wheat – Puccinia graminis tritici
Loose smut of wheat – Ustilago nuda
Wilt of tomato – Fusarium oxysporum f.sp. lycopersici
Red rot of sugarcane – Colletotrichum falcatum
Early blight of potato – Alternaria solani
Important diseases caused by phytopathogenic bacteria
Angular leaf spot of cotton, bacterial leaf blight of rice, crown galls, bacterial

Desirable to know

7

Cankers of citrus
Important diseases caused by phytoplasmas
Aster yellow, citrus stubborn
Important diseases caused by viruses
Papaya ring spot, tomato yellow leaf curl, banana bunchy top, rice tungro
Important diseases caused by viroids
Potato spindle tuber, coconut cadang cadang

Nice to know

3

5

PRACTICAL

To study the effect of pH on the growth of E. coli

Demonstration of alcoholic fermentation.

Effect of different nitrogen sources on growth of E. coli.

Effect of different carbon sources on growth of E. coli.

Isolation of microbes (bacteria & fungi) from soil (28.C & 45.C )

Isolation of Azotobacter/Azospirillum from soil

Must know

30

Analysis of soil – pH, moisture content, water holding capacity, percolation, capillary action

Isolation of microbes (bacteria & fungi) from rhizosphere and rhizoplane.

Detection (qualitative) of the presence of enzymes (dehydrogenase, amylase, urease) in soil.

Isolation of Rhizobium from root nodules of legumes

Desirable to know

15

Isolation of phosphate solubilizers from soil

Demonstration of Koch’s postulates in fungal, bacterial and viral plant pathogens.

Study of important diseases of crop plants by cutting sections of infected plant material –Albugo, Puccinia, Ustilago, Fusarium, Colletotrichum.

Nice to know

15

Suggested readings:

  1. Atlas RM and Bartha R. (2000). Microbial Ecology: Fundamentals & Applications. 4th edition. Benjamin/Cummings Science Publishing, USA.
  2. Atlas RM. (1989). Microbiology: Fundamentals and Applications. 2nd Edition, MacMillan Publishing Company, New York.
  3. Madigan MT, Martinko JM and Parker J. (2009). Brock Biology of Microorganisms. 12th edition. Pearson/ Benjamin Cummings
  4. Agrios GN. (2006). Plant Pathology. 5th edition. Academic press, San Diego,
  5. Lucas JA. (1998). Plant Pathology and Plant Pathogens. 3rd edition. Blackwell
  6. Science, Oxford.
  7. Mehrotra RS. (1994). Plant Pathology. Tata McGraw-Hill Limited
SGTUNIVERSITY
X