QUESTIONS

QUESTIONS

Q.1. Fill in the blanks:
i. Sclerotinia crown rot causes --------------- of seedlings or ------------of older plants.
ii. Sclerotinia sclerotiorum survives as ----------------in the soil.
iii. Xanthomonas campestris pv. pelergonii is an-----------, ------------, non-spore forming round rods, motile with--------------- flagellum.
iv. Geranium Leaf curl virus is transmitted by -----------vector, plant parts, -------------and----------.
v. Bacterial fasciation is caused by ------------------.

Answer key
i damping-off, crown –rot ii sclerotia iii aerobic, gram-negative, polar iv white fly, grafting, sap v Corynebacterium fascians

Q.2. Tick the correct option:
(i) Crown rot of geranium is caused by
(a) Rhizoctonia solani (b) Sclerotinia sclerotiorum (c) Fusarium solani
(d) Verticillium
(ii) Bacterail blight of geranium is caused by
(a) Xanthomonas campestris pv. pelargonii (b) Pseodomonas campestris pv. pelargonii (c) Clavibactor pelargonii (d) Pseodomonas syringae pv. pelargonii
(iii) The optimum for the growth of Bacterial blight pathogen is
(a) 25-27oC (b) 20-25oC (c) 15-20oC (d) 30-35oC
(iv) The crown rot pathogen survive in the form of
(a) Chlymadospore (b) Sclerotia (c) Conidia (d) Oospores
(v) Xanthomonas campestris pv. pelargonii is an
(a) aerobic, gram-negative (b) aerobic, gram-positive
(c) anaerobic, gram-negative (d) anaerobic, gram-positive

Answers: (i) b, (ii) a, (iii) a, (iv) b (v) a

Q.3. Write down the causal organism and characteristic symptoms of following diseases:
a. Alternaria leaf spot of geranium
b. Bacterial blight of geranium
c. Geranium leaf curl

Q.4. Write down the management practices for the following diseases:
a. Sclerotinia crown rot of geranium
b. Alternaria leaf spot of geranium
Last modified: Wednesday, 7 December 2011, 9:23 AM