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 botany living world mycorrhiza classification of fungi kingdom monera, protista and fungi useful and harmful microbes

Fungal hyphae remain intercellular in

  1. Endomycorrhiza

  2. VAM

  3. Ectomycorrhiza

  4. Both A and B
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In ectomycorrhiza, the fungal hyphae form a mantle around the root and grow between the cortical cells (intercellularly) without penetrating the cell walls. Endomycorrhiza (including VAM) involves intracellular penetration.

Multiple choice botany living world mycorrhiza classification of fungi kingdom monera, protista and fungi useful and harmful microbes

VAM is component of _________

  1. Ectomycorhiza

  2. Endomycorhiza

  3. Green manure

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

The ectomycorrhiza is an association that takes place at the surface of the roots whereas the endomycorrizal fungi penetrate into the root cortex and form arbuscules within the root cells.

Vesicular Arbuscular Mycorrhizal (VAM) is a fungus that penetrates the roots of a vascular plant and helps them to capture the nutrients from the soil. 
So, VAM is a component of endomycorhiza.

Multiple choice botany living world mycorrhiza classification of fungi kingdom monera, protista and fungi useful and harmful microbes

VAM is

  1. Vesicular-arbuscular mycorrhiza

  2. Variable adenine mutation

  3. Variable associative mutualism

  4. Vitamins and minerals
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Fungi forms symbiotic association with roots of higher plants, known as mycorrhizae. When fungal hyphae penetrate through cortex cells of root, these are called as Endomycorrhizae. These are also called vesicular arbuscular mycorrhizae or VAM, because cortical cells swell and form vesicles or arbuscles. it has significant role in phosphorus nutrition in plants. hence, Option A is correct. 

Multiple choice botany living world mycorrhiza classification of fungi kingdom monera, protista and fungi useful and harmful microbes

The fungus which grows around the root surface is called

  1. Endomycorrhizae

  2. Ectomycorrhizae

  3. Rhizomorph

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

Mycorrhiza is an association between a fungus and the root of the higher plant, for example, pinus, eucalyptus etc.

The ectomycorrhizae is a fungal association in which the fungus partner is commonly basidiomycetes. The fungus completely encloses the roots in a mantle of tissues formed of compact hyphal cells but do not penetrate inside the root cells like in endomycorrhiza
So, the correct answer is option B.

Multiple choice botany living world mycorrhiza classification of fungi kingdom monera, protista and fungi useful and harmful microbes

Mycorrhiza is a symbiotic association between 

  1. Algae and Fungi

  2. Algae and Roots of plants

  3. Fungi and Roots of plants

  4. Viruses and Bacteria
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Fungi present in the roots of the plants show a symbiotic relationship with each other. It helps the roots of the plants to absorb more nutrients and water from the soil. It also helps them obtain better resistance to environmental stresses. In return, plants provide shelter and nutrition to mycorrhiza.

So, option C is the correct answer.

Multiple choice botany living world mycorrhiza classification of fungi kingdom monera, protista and fungi useful and harmful microbes

Mycorrhiza is an example of 

  1. Symbiotic relationships

  2. Ectoparasitism

  3. Endoparasitism

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

Mycorrhiza is a symbiotic relation seen between certain plants and fungi. The fungi live on the roots of certain plants and help them absorb water and nutrients from the soil in a better way. In return, plants provide shelter and nutrition to fungi. So, both the organisms mutually befit each other.

So this type of relationship is called symbiotic relationship.

Multiple choice botany living world mycorrhiza classification of fungi kingdom monera, protista and fungi useful and harmful microbes

Give a brief account on VAM.

  1. Forms fungal sheath around root

  2. Fungal hypha grows intracelluarly

  3. Fungal hypha destoys cortical cells to rach phloem of the plant

  4. Forms hartig net in the intercellular spaces of cortex
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Mycorrhiza is the product formed by the symbiotic association between the fungus and the roots of higher plants. Vesicular Arbuscular Mycorrhizae (VAM) is the symbiotic association between Phycomycetes fungus and the roots of angiospermic plants forming a mycelial sheath and also acts as a biofertilizer.
Some of the main characteristic features are :
• Helps to absorb important macro and microelements and water
• Compatible with other biofertilizers
• Provides protection to the plants from pathogenic fungi and nematodes 
• Does not affect ecological balance and environmental friendly.
So, the correct answer is 'Forms fungal sheath around root'
Multiple choice botany living world mycorrhiza classification of fungi kingdom monera, protista and fungi useful and harmful microbes

Fungus which is found in Pinus root is

  1. Amanita

  2. Corticium

  3. Fornes

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Mycorrhiza is the term used to define the association of fungi on roots of vascular plants. In the case of woody plants such as pine, birch and oak, the fungi belonging to the phyllum; Basidomycota and Acomycota form the mycorrhizal assoociations. Ectomycorrhizas, such as Amanita and Boletus form mycorrhizas on Pinus.

Thus, the correct answer is option A.

Multiple choice botany living world mycorrhiza classification of fungi kingdom monera, protista and fungi useful and harmful microbes

Mycorrhiza is an association between roots of higher plant and fungus. It is an example of

  1. Symbiosis

  2. Parasitism

  3. Helotism

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Biologically, mycorrhiza is defined as an association of fungi and roots of vascular plants. In a mycorrhizal association, the fungus tends to colonise the host plant roots either intracellular or extracellular. However, this is a symbiotic association, which is generally mutualistic and rarely pathogenic.

Thus, the correct answer is option A.  

Multiple choice biology breeding and biotechnology method of plant breeding for crop improvement plant breeding for food production biotechnology

Which of the following is incorrectly matched?                         

  1. Disease - Black rot of crucifers; Causative Organism - Bacteria

  2. Disease - Brown rust of wheat; Causative Organism - Fungi

  3. Disease - Late blight of potato; Causative Organism - Virus

  4. Disease - Red rot of sugarcane; Causative Organism - Fungi
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Late blight of potato is caused by Phytophthora infestans a oomycetae (fungi). Cool climate and wet weather help infection and spread, responsible for the irish famines in the nineties.

So, the correct answer is 'Disease - Late blight of potato; Causative Organism - Virus'