Plant Diseases

Brown leaf spot of sugarcane is caused by Cercosporidium longipes.

Downy mildew disease of African daisy plant is caused by fungus- Plasmopara majewskii. Cercospora gerberae causes Cercospora leaf spot disease in African daisy plant.
Nectria canker disease is caused by Haematonectria haematococca fungus in African daisy plant. Powdery mildew is caused by the fungal pathogen Erysiphe cichoracearum in African daisy plant.
Southern blight disease is caused by Sclerotium rolfsii in African daisy plant.
Hence, 1 and 2 are false statements.

The causing fungal pathogens responsible for bird’s eye rot are Elsinoe ampelina and Sphaceloma ampelinum.
Angular leaf spot of grapes is caused by the fungus Mycosphaerella angulata.
Hence, the correct answer is Elsinoe ampelina and Sphaceloma ampelinum.

1. Leaf streak disease is caused by the fungus Stenocarpella macrospora in maize.
2. The causing fungal pathogen for stem rot of paotato is Sclerotium rolfsii.
3. Athelia arachnoidea causes crater rot in carot.
4. Grey rot or noble rot disease is caused by Botrytis cinerea in grapes. Mycosphaerella angulata and Cercospora brachypus cause angular leaf spot in grapes.
   Hence, only statement 4 is false.

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.

The causative agent for wart disease of potato is Synchytrium endobioticum.

1. The causative agents for areolate leaf spot in citrus are- Thanatephorus cucumeris, Pellicularia filamentosa and Rhizoctonia solani. Dry fruit rot is caused by Nematospora coryli in citrus.
2. Nectria canker disease is caused by Haematonectria haematococca fungus in African daisy plant. Powdery mildew is caused by the fungal pathogen Erysiphe cichoracearum in African daisy plant.
3. Bitter rot of peanut is caused by the fungal pathogen Glomerella cingulata.
   Hence, 1 and 2 both are false statements.

Infected heads emerge as a mass of dark brown powdery spores is called loose smut. Fungus Ustilago tritici causes loose smut disease in barley.
Covered smut is caused by the fungus Ustilago segetum var. hordei in which the heads that emerge are dark in colour and smut balls take the place of the grain. Wirrega blotch of leaf is caused by the fungus Pyrenophora wirreganensis.

Gymnosporangium clavipes causes quince rust in apple.

Leaf spot of cherries and palms is caused by Blueriella sp.
Brown leaf spot of grapes is caused by Cerecosoridium viticola.
Citrus greasy leaf spot is caused by the fungus Mycosphaerella citri.
Banana leaf spot is caused by Mycosphaerella musicosa.
Taphrina deformans causes leaf curl of peach and apricot.
Hence, the correct sequence of codes is A - 3, B - 1, C - 5, D - 2.

Pseudopezicula tetraspora is a fungus and causes angular leaf scorch in grapes.

Pseudopezicula tetraspora is a fungus and causes angular leaf scorch in grapes. The causing fungus for ring spot in sugarcane is Leptosphaeria sacchari. Collar canker of tea is caused by Phomopsis theae. Cotton root rot of crucifer is caused by the fungus Phymatotrichopsis omnivore.
Hence, the correct answer using the codes is A - 3, B - 1, C - 4, D - 2.

Red blister disease of coffee is caused by Cercospora coffeicola. Dry root rot disease of coffee is caused by Fusarium solani.
Thread blight disease is caused by Corticium koleroga in coffee. Phoma costaricensis causes tip blast disease in coffee.
Tracheomycosis is caused by the fungus Gibberella xylarioides in coffee.

Cottony snow mold of wheat is caused by the fungus Coprinus psychromorbidus. White leaf spot of crucifer is caused by Pseudocercosporella capsellae. Hull rot disease of almond is mainly caused by Rhizopus sp. Southern blight of cotton is caused by the fungal pathogen Sclerotium rolfsii.
Hence, the sequence of codes A - 2, B - 4, C - 3, D - 1 is correct.

A general purpose tree fruit spray, available under a variety of trade names, is effective for control of many of the common diseases and insect pests of apple. This mixture usually contains captan as the fungicide component and methoxychlor and malathion or carbaryl as the insecticide component. Other alternative to control of fungal diseases are-

1. coppers (fixed)- early season control of scab and fire blight;
2. fenarimol- control of scab, mildew, and rust;
3. ferbam- some control of scab, rust, black rot, and the summer diseases; causes undesirable
   black residue when used late in season;
4. maneb, mancozeb- control of rust, scab, fruit rots, and summer diseases;
5. myclobutanil- control of scab, powdery mildew and cedar-apple rust;
6. sulfur- for control of mildew; some control of scab, summer diseases, and fruit rots; can be
   phytotoxic to some cultivars and may cause fruit russetting and/or yield reduction when sprayed
   after bloom;
7. thiram- some control of scab, rust, and summer diseases;
8. thiophanate-methyl- control of scab, fruit rots, and summer diseases;
9. triadimefon- very good control of powdery mildew and rust.