Biology

Microbes and Plant Diseases

1,118 Questions

Microbes and plant diseases examine the role of fungi, bacteria, and viruses in causing infections in plants and humans. Topics cover symbiotic associations like mycorrhiza, fungal structures, and specific agricultural pathogens. Practice these biology questions to master microbiology concepts for upcoming competitive examinations.

Fungal associationsPlant pathogensMicrobial structuresBacterial infections

Microbes and Plant Diseases Questions

Multiple choice evs improvement in food resources crop yield improvement food supply crop improvement methods and organisations

Wheat crop field infected with hill burnt often stinks. The foul odour is due to the presence of _______________.

  1. Methane in infected part

  2. Hydrogen Sulphide in spore mass

  3. Trim ethylamine in spore mass

  4. Alcohol in feted plants
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Wheat infected with hill bunt or stinking smut produces spores that release trimethylamine, which gives the infected crop a characteristic rotting fish or foul odour.

Multiple choice evs soil- our life soil profile soil and crops soil - types, uses and need for conservation

Consider the following fungi:
1. Arthrobotrys oligospora
2. Dactylella cionopaga
3. Streptorrryces rimosus
Which of these are predaceous for the biological control of nematodes in soil?

  1. 1 and 2

  2. 1 and 3

  3. 2 and 3

  4. 1, 2 and 3
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Arthrobotrys oligospora and Dactylella cionopaga are well-documented predatory fungi that trap and consume nematodes using specialized structures like adhesive nets or rings. Streptomyces rimosus (note spelling: Streptomyces) is a soil bacterium producing antibiotics, not a predatory fungus.

Multiple choice bio-chemistry digestive system of human role of intestine digestion in intestine digestive system - organs

Nonpathogenic bacterium present in large intestine is

  1. Staphylococcus aureus

  2. Escherichia coli

  3. Helicobacter pylori

  4. Leptospira interogans
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Escherichia coli is a well-known nonpathogenic bacterium that resides in the human large intestine as part of the normal gut flora. It aids in vitamin synthesis and prevents the colonization of harmful bacteria.

Multiple choice biology seeds - structure and germination germination seed germination the flower

In which one of the following pathogens do the cells of promycelium after the germination of teleutospore produced infection hyphae instead of basidiospores?

  1. Ustilago scitaminae

  2. Tilletia foetida

  3. Tilletia tritici

  4. Ustilago tritici
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In Ustilago scitaminae, the promycelium typically produces infection hyphae directly rather than forming basidiospores, which is a characteristic feature of this smut fungus.

Multiple choice botany root - external morphology root systems root system in plants forms of root

Primary inoculums of red rot of sugarcane comes from _______________.

  1. Mycelium in reddened pith

  2. Conidia and mycelium in buds

  3. Acervuli in the rind

  4. Conidia and mycelium in debris
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Red rot of sugarcane is caused by Colletotrichum falcatum. The primary inoculum is the mycelium that survives in the infected pith of the sugarcane stalks used for planting.

Multiple choice botany know the plant world closely diversity in plants types of nutrition in plants different modes of nutrition in plants

Facultative saprophyte is?

  1. A parasite which can live as a saprophyte

  2. Always a parasite

  3. Always a saprophyte

  4. May acquire parasite mode of life
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A facultative saprophyte is an organism that is primarily a parasite but has the ability to survive as a saprophyte (feeding on dead organic matter) under certain conditions.

Multiple choice botany know the plant world closely diversity in plants types of nutrition in plants different modes of nutrition in plants

A mutant micro-organism unable to synthesize a compound required for its growth, but able to grow if the compound is provided, is known as

  1. Auxotroph

  2. Prototroph

  3. Autotroph

  4. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
An auxotroph is a mutant microorganism that requires some nutrient that is not normally required by the organism (prototroph) from which the mutant was derived. 
A microorganism that has the ability to synthesize all of its amino acids, nucleic acids, vitamins, and other cellular constituents from inorganic nutrients is known as prototroph.  
Autotrophs are those organisms that are able to make energy-containing organic molecules from inorganic raw material by using basic energy sources such as sunlight. 
Thus, the correct answer is option A.

Multiple choice botany know the plant world closely diversity in plants types of nutrition in plants different modes of nutrition in plants

Which statement is correct about saprophytes ?

  1. They do not possess chlorophyll

  2. They survive on other organisms

  3. They live on dead organism

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Saprophytes are the class of organism that have saprophytic mode of nutrition. They feed on dead living organism. They are assumed to have evolved from green plants but have lost their chlorophyll during the course of evolution.

Multiple choice evs - i food for all improved methods of agriculture receding water table water conservation and irrigation cropping patterns whose forests?

Storage grains produce aflatoxin due to growth of

  1. yeast

  2. mould

  3. Aspergillus

  4. virus.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Aspergillus consists of several hundred mould species found in various climates worldwide. Aspergillus is highly aerobic and are found in almost all oxygen rich environments. The storage grain produces aflatoxin due to growth of Aspergillus which can cause acute liver damage and cancer.