Tuesday, March 31, 2020

Multiple choice questions on pear diseases

Yesterday I finished objective questions on apple. Today I am posting MCQs on pear diseases. I hope this will help you in preparing for your examination

Q 1 Pear scab is caused by.
a. Podospharea leucotricha
c. Gymnosporangium libocedri
b. Fabraea maculata
d. Venturia pirina
Q 2 Sexual spores of Pear scab develop in
a. Pseudothecia on infected fallen leaves
c. Perithecia on infected fallen leaves
b. Cleistothecia on infected fallen leaves
d. Apothecia on infected fallen leaves
Q 3 Vector for pear decline disease is  
a. Pear psylla
c. Pear aphid
b. Green peach aphid
d. Woolly Apple Aphid
Q 4 Sexual fruiting body of powdery mildew causing fungi is
a. Peritheicium
c. Cleistothecium
b. Apothecium
d. Pseudotheium
Q 5 Primary source of inoculum for powdery mildew of pear is
a. ascospores borne in cleistothecium
c. dormant mycelia in infected buds
b. barrel shaped conidia
d. superficial mycelia on infected buds
Q 6 Erwinia amylovora overwinters in
a. natural openings or woulds
c. Nectrathodes
b. bark tissues along edges of cankers
d. Venturia pirina
Q 7 Primary source of inoculum for pacific coast pear rust is
a. Telial galls on cedar plants
c. Uredia on flowering pear (Pyrus calleryana)
b. Urediospores
d. Aceiospores
Q 8 Biological control agent for powdery mildew of pear is
a. Erwinia herbicola
c. Ampelomyces quisqualis
b. Pseudomonas fluorescens
d. All of these
Q 9 Fruiting body produced by Ampelomyces quisqualis is
a. Pycnidium
c. Cleistothecium
b. Apothecium
d. Pseudotheium
Q 10 Fire blight can be managed by  
a. pruning diseases parts
c. Using COC or Streptocycline
b. controlling insect vectors
d. all of these

Answer these questions in comment section. I shall be posting the answers tomorrow in the comment section.

Monday, March 30, 2020

Objective questions on apple

Yesterday I posted some objective questions on apple in the form of fill in the blanks. Today again I am going to post some more fill in the blanks with reasoning questions. This will complete important questions from apple fruit crop.

Fill in the blanks:
  1. Unlike apple scab fungus, the spores of powdery mildew do not require _____________ for germination.
  2. Black rot disease of apple is caused by                               and is also known as                         .
  3. Phytophthora cactorum  survives in the soil as                                      that are resistant to drought and relatively resistant to chemical treatment.
  4. Characteristic feature of white root rot is                                                that can be seen on roots during monsoon months and can be seen on soil level.
  5. Young trees if infested with                                                   may die quickly with necrotic leaves still on the dead plant is a characteristic symptom.
  6. Soil pH                 , soil moisture                 and Temperature                  play an important role in incidence and survival of Dematophora necatrix.
  7. Crown gall of apple is caused by                                 and hairy root is caused by                       can be managed by bio-control agent                                                   strain

Descriptive questions

  1. How excess nitrogen makes the plants more susceptible? What is the role of balanced nutrition in disease management?
  2. Why overhead irrigation be avoided during fire blight outbreak?
  3. Why control of insects with sucking type of mouth parts is important in management of fire blight of pome fruits?
You may answer the fill in the blanks in comment section. I shall be posting the answers in comment section tomorrow.

Sunday, March 29, 2020

Objective questions on apple diseases.

Yesterday I started working on objective type questions for the diseases of apple crops. In this series I am going to  post fill in the blanks. Here are few fill in the blanks for apple diseases.

Fill in the blanks

  1. Apple scab is caused by _______________ is telomorph, whereas, anamorph of the fungus is ______________.
  2. Apple scab disease perinnates in ____________and primary infection is caused by ______________.
  3. Leaf __________period and _____________plays important role in primary infection of apple scab.
  4. Secondary source of inoculum for scab development is __________.
  5. Application of _________to leaf litter during fall (when more than 80% leaves have fallen) hasten decomposition of leaves due to microbial action and reduces primary inoculum.
  6. In case of fire blight of apple, tips of young infected shoots wilt, forming a very typical ________________symptom.
  7. The fire blight bacteria ____________in bark tissues along the edges of cankers caused by infections during previous years.
  8. The Erwinina amylovora penetrate the tree through __________or ______________.
  9. Secondary infection of Erwinina amylovora arises from _______of fresh infections.
  10. Podosphaera leucotricha overwinters in the ____________that had been infected in the preceding growing season.

You may answer these questions in comment section. I shall be answering these in comment section tomorrow. 

Saturday, March 28, 2020

Question Bank for Apple Diseases

During the period of lockdown, I thought to help my students in preparation for their exams. Today I am starting with few questions on apple diseases, which may come handy for your exams in near future. Tomorrow I shall be posting some more questions.


Q 1 The disease which had endangered the very existence of delicious apples.
a. Powdery mildew
c. Fruit spots
b. Apple scab
d. Root rot

Q 2 The breeding of scab resistant varieties of apple was undertaken.
c. RFRS – Mashobra
d. RFRS – Bikaner

Q 3 The root rot of apple is caused by.
a. Phytophthora cactorum
c. Corticium salmonicolor
b. Podospharea leucotricha
d. Botryosphaeria obtusa

Q 4 Silvering of foliage appears soon after petal fall is the typical symptoms of
a. Nail head canker
c. Pink disease
b. Leaf canker
d. Fruit spots

Q 5 Hairy root is due to.
a. Agrobacterium tumefaciens
c. Podospharea leucotricha
b. Dematophora necatrix
d. Corticium salmonicolor

State True /False

Q 6 The Primary Source of Inoculum  for apple scab is zoospores of pseudothecium.
Q 7 The apple rust is a heterocious & also monocyclic disease.
Q 8 Apple crown rot. Root rot, Collar rot are the complete loss disease caused by a single organism Dematophora necatrix.
Q 9 Apple Dapple /Apple scar skin is a viroid disease.
Q 10 The two crab apples Malus floribunda & Malus toringoides are have resistance against the root rot.
Q 11 Bitter rot, Sour rot, Brown rot are not post harvest diseases.
You may answer these questions in comment box. I shall be posting the answers soon in comment section