Diseases of Vegetable, Ornamental and Spice Crops

QUESTIONS

Q.1. Fill in the blanks:

i. The symptoms of Pythium black leg are -------------------areas at the base of cuttings.
ii. Botrytis blight is caused by ------------------------.
iii. The sporulation of Botrytis cinerea is maximum at --------------but decreases with high temperature -------------.
iv. ----------------- does not form micro sclerotia while -----------------forms true microsclerotia.
v. Fungicides such as----------------, and ---------------or their combination can be used as protectants against Botrytis blight.

Answer key

i. Brown water-soaked ii. Botrytis cinerea iii. 20-25oC, 30oC iv. V. albo –atrum, V. dahlia v. Benomyl (0.05%), chlorothalonil (0.2%)

Q.2. Tick the correct option:

(i) Rust of geranium is caused by

(a) Puccinia pelargonii-zonalis (b) Uromyces pelargonii-zonalis
(c) Puccinia tritici (d) Phragmidium pelargonii-zonalis

(ii) Verticillium wilt is caused by

(a) Verticillium albo-atrum (b) V.dahliae (c) Both a and b (d) Neither a or b

(iii) The sporulation of the Botrytis blight pathogen decreases at

(a) 20-25oC (b) 30oC (c) 10 oC (d) 5oC

(iv) Puccinia pelargonii-zonalis overwinters in diseased leaves in form of

(a) Teliospores (b) Aeciospores (c) Basidiospores (d) Uredospores

(v) Conducive time for the spread of the Verticillium wilt disease is

(a) Summer months (b) Winter months (c) Rainy season (d) Spring months

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

Q.3. Write down the causal organism and characteristic symptoms of following diseases:

a. Botrytis blight of geranium
b. Rust of geranium

Q. 4. Write down the management practices for the following diseases:

a. Verticillium wilt of geranium
b. Pythium black leg