This option is correct beause violet root rot is caused by Helicobasidium mompa.

Pepper leaf spot is caused by the fungus Leptosphaerulina briosiana in Alfalfa.

Penicillium digitatum causes Green fruit mold in citrus. Mucor fruit rot is caused by Mucor sp. (Mucor paronychia, Mucor racemosus).

Tropical cotton rust is caused by the fungus, Phakopsora gossypii. The disease-causing agent for powdery mildew in pea is Erysiphe pisi. Wood rot of pear is caused by the fungus, Trametes versicolor. Helminthosporium solani causes silver scurf disease in potato. Hence, the correct answer using the codes is P - 1, Q - 4, R - 2, S - 3.

Leaf spot of cherries and palms is caused by Blueriella sp. The causative agent for ergot disease in Barley is Claviceps purpurea. Citrus greasy leaf spot is caused by the fungus Mycosphaerella citri. Banana leaf spot is caused by Mycosphaerella musicosa.

Tracheomycosis is caused by the fungus Gibberella xylarioides in coffee.

In Barley, white to tan, small, semi-rectangular spots or blotches with a dark brown edge aligned along the veins of the leaf blade is known as Halo spot disease. The causative fungus of the said disease is Pseudoseptoria stomaticola.

The causing fungal pathogens responsible for bird’s eye rot are Elsinoe ampelina and Sphaceloma ampelinum.

P. Leaf streak disease is caused by the fungus, Stenocarpella macrospora in maize. Q. The causing fungal pathogen for stem rot of potato is Sclerotium rolfsii. R. Athelia arachnoidea causes crater rot in carrot. S. 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 S is false.

In raspberry, Elsinoe veneta causes anthacnose disease.

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.

Stem rot of rice is caused by Magnaporthe salvini and Sclerotium oryzae. False eye spot disease of wheat is caused by the fungus, Gibellina cerealis. Gray spot of tea is caused by Phyllosticta dusana. The causing agent for target blotch in sugarcane is Helminthosporium sp. Hence, the correct answer using the codes is P - 2, Q - 4, R - 3, S - 1.

Green fruit rot of almond is caused by Sclerotinia sclerotiorum. The causative agent for twig blight of apricot is Monilinia sp. like M. fructicola and M. laxa. Clitocybe root rot of apple is caused by the fungus Armillaria tabescens. Collar rot of cacao is caused by the fungus Ustulina deusta. Hence, the correct sequence of codes is P - 5, Q - 1, R - 4, S - 2.

Black stripe disease in sugarcane is caused by Cercospora atrofiliformis. Peronosclerospora sacchari fungus causes Downy mildew disease in sugarcane.

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 is P - 3, Q - 1, R - 4, S - 2.