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

The causative pathogen(s) for ‘Sooty blotch’ of apple is/are A. Peltaster fructicola B. Leptodontidium elatius C. Chondrostereum purpureum D. Helicobasidium mompa

  1. Only A

  2. Both A and B

  3. Both B and C

  4. Both C and D

  5. Only D
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Sooty blotch colonies appear dusty to olive green or black on mature fruit depending on the particular fungus species involved. Sooty blotch causing fungal pathogens are- Peltaster fructicola, Geastrumia polystigmatis, Leptodontidium elatius, Gloeodes pomigena. Silver leaf disease is caused by Chondrostereum purpureum in apple. Violet root rot is caused by Helicobasidium mompa.

Multiple choice

Match the Almond diseases in List - A with causing fungal pathogens in List - B.

 
List - A
List - B
A. Armillaria root rot 1. Venturia carpophila
B. Green fruit rot 2. Rhizomorpha subcorticalis
C. Hull rot 3. Rhizopus sp
D. Scab

  1. A - 2, B - 4, C - 3, D - 1

  2. A - 3, B - 1, C - 4, D - 2

  3. A - 2, B - 4, C - 1, D - 3

  4. A - 1, B - 3, C - 2, D - 4

  5. A - 2, B - 1, C - 3, D - 4
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Armillaria root rot is caused by the fungi- Armillaria mellea and Rhizomorpha subcorticalis in Almond. Green fruit rot disease of Almond is caused by Botrytis cinerea, Botryotinia fuckeliana and Monilinia fructicola. Hull rot disease of Almond is mainly caused by Rhizopus sp.Venturia carpophila and Cladosporium carpophilum cause Scab disease of Almond. Hence, the sequence of codes A-2, B-4, C-3, D-1 is correct.

Multiple choice

Brown rot in pear is caused by

  1. Bacillus amylovorous

  2. Monilinia fructicola

  3. Fusarium moniliformae

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

 Brown rot in pear is caused by Monilinia fructicola.Brown rot causes blossom blight, twig blight; twig canker and fruit rot.

Multiple choice

Which of the following is an edible ascomycete?

  1. Mushrooms

  2. Agaricus

  3. Morchella

  4. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

 Morchella is an edible ascomycete. These distinctive fungi appear honeycomb-like, with their cap composed of a network of ridges with pits.

Multiple choice

Which of the following produce aromatic antibodies?

  1. Streptomyces omiyanesis and Bacillus subtilis

  2. Penicillium patulum and Streptomyces venezuelae

  3. Bacillus polymyxa and Streptomyces venezuelae

  4. Streptomyces roseosporus and Streptomyces lincolnensis
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Penicillium patulum and Streptomyces venezuelae produce aromatic antibiotics griseofulvin and chloremphenicol, respectively.

Multiple choice

Diabetic patients and malnourished children are most susceptible to which among the following fungal diseases?

  1. Candidiasis

  2. Cryptococcosis

  3. Zygomycosis

  4. Aspergillosis

  5. Hyalohyphomycosis
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Zygomycosis in the debilitated patient is the most acute and fulminate fungal infection known. The disease typically involves the rhino-facial-cranial area, lungs, gastrointestinal tract and skin. It is often associated with acidosis, diabetes, malnourished children, severely burned patients and other diseases such as leukemia and lymphoma.

Multiple choice

Central auditory processing disorder (CAPD) is a complex problem affecting about 10% of school-aged children. These patients are more prone to be infected by which among the following fungi?

  1. Candida norvegensis

  2. Candida guilliermondii

  3. Candida parapsilosis

  4. Candida lusitaniae

  5. Candida tropicalis
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Candida norvegensis is a very rare clinical isolate that has been reported as a causative agent of peritonitis and disseminated candidiasis in a patient on CAPD.

Multiple choice

Keratin is a fibrous scleroprotein that occurs in the outer layer of the skin and in horny tissues such as hair, feathers, nails and hooves. Which among the following diseases is caused by a fungus which has the ability to utilise keratin as a nutrient source for its growth?

  1. Paronychia

  2. Pityriasis folliculitis

  3. Dermatophytosis

  4. Chronic candidal onychomycosis

  5. Candidiasis
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Dermatophytosis of the scalp, glabrous skin and nails is caused by dermatophytes which have the ability to utilise keratin as a nutrient source. No living tissue is invaded the keratinised stratum corneum is simply colonised.