Diseases of Vegetable, Ornamental and Spice Crops

QUESTIONS

Q.No. 1. Tick the correct answer:
1. Stalk rot of cauliflower is caused by :

a) Macrophomina phaseolina b) Rhizoctonia solani c) Sclerotium rolfsii d) Sclerotinia sclerotiorum

2. Stalk rot pathogen overwinter in:

a) Seed b) Soil c) Plant debris d) None

3. Sclerotinia sclerotiorum survives in soil in the form of:

a) Sclerotia b) Oospore c) Chlamydospore d) Perethecia

4. Stalk rot of cauliflower can be effectively managed by crop rotation with:

a) Tomato b) Peas c) Paddy d) Beans

5. Stalk rot can be managed effectively by sprays of :

a) Carbendazim b) Copper oxychloride c) Bordeaux mixture d) Wettable sulphur

6. Optimum temperature for stalk rot development is:
a) 10-15o C b) 15-20o C c) 20-25o C d) 25-30o C
7. Stag head is the characteristic symptom of :

a) Stalk rot b) Downy mildew c) White rust d) Black rot

8. Albugo candida is:

a) Saprophyte b) Obligate c) Necrotroph d) None

9. Albugo candida survives in the form of:

a) Chlamydospore b) Oospore c) Sclerotia d) Hyphae

Answers: 1. d 2. b 3. a 4. c 5. a 6. b 7. c 8. b 9. b

2. Fill in the Blanks:

1. Stalk rot is an important disease of ------------------------ crop of crucifers.
2. Sclerotinia sclerotiorum overwinters in the form of ----------------------------.
3. In the presence of proper----------------- and -------------------, sclerotia of Sclerotinia sclerotiorum germinate by forming apothecia.
4. Application of ------------------ aggravates stalk rot of cauliflower.
5. White rust or blister infection occur in ------------------ phase and ------------------ phase.
6. White rust of crucifers is caused by ------------------.
7. Albugo candida survives in soil in the form of ----------------------.

Answers

1.Seed 2. Sclerotia 3. Humidity, Light 4. Nitrogen 5. Local or leaf, Systemic or stag 6. Albugo candida 7. Oospores

Subjective type questions

1. Write down the causal organism and characteristic symptoms of following diseases:

a. Club root of crucifers
b. Stalk rot of crucifers
c. Downy mildew of crucifers

2. Write down the management practices for the following diseases:

a. Stalk rot of cabbage
b. Black rot of cabbage and cauliflower
c. White rust of crucifers

3. Write down the disease cycle and epidemiology of following disease:

a. White rust of crucifers
b. Downy mildew of crucifers