Test: Plant Diseases - SSC CGL MCQ

A plant disease is defined as "anything that prevents a plant from performing to its maximum potential." Plant diseases can be caused by various factors such as pathogens like viruses, bacteria, fungi, and parasites. These diseases can affect the growth, development, and overall health of plants, leading to symptoms that indicate the presence of a disorder. Proper plant disease management is crucial for maintaining healthy crops and landscapes.

Granville wilt is a plant disease caused by Pseudomonas solanacearum, affecting plants like tobacco, tomato, potato, eggplant, pepper, and others. It is identified by symptoms such as stunting, yellowing, wilting of above-ground parts, and the decay of roots turning black or brown. This disease can have a significant impact on the affected plants' health and productivity.

Soft rot, caused by Erwinia carotovora, affects various fleshy tissue fruits like cabbage, carrot, celery, and onion. The disease results in the soft decay of these tissues, leading to a mushy and soft texture. This can have detrimental effects on the affected crops, causing significant economic losses for farmers.

Citrus stubborn disease, caused by Spiroplasma citri (MLO), affects citrus and stone fruits, resulting in symptoms like chlorosis, yellowing of leaves, shortened internodes, and wilting. This disease can impact the overall health and yield of citrus and stone fruit trees, affecting the fruit quality and production.

Tobacco mosaic, caused by Tobacco mosaic virus (TMV), affects plants like tobacco, tomato, and numerous other vegetables and weeds. It is characterized by the mottled appearance of leaves in a mosaic pattern, along with symptoms of dwarfing. This disease can have significant implications for crop health and productivity.

Fusarium wilt of tomato is a disease caused by Fusarium oxysporum affecting tomatoes. This disease leads to the bending down of leaves and stunted growth due to the appearance of dark streaks in the vascular tissue. Fusarium wilt is a significant concern for tomato growers as it can severely impact plant health and yield.

Dutch elm disease is recognized by symptoms such as wilted leaves that turn dull green to yellow or brown and eventually drop off. This disease is caused by the fungus Ceratocystis ulmi and is known for its devastating impact on elm tree populations worldwide.

Black knot is a fungal disease affecting plum and cherry trees, characterized by the development of small black knotty swellings on twigs and branches. These swellings can lead to significant damage if left untreated, impacting the health and productivity of the trees.

Citrus exocortis, caused by Citrus exocortis viroid (CEV), is identified by vertical splits in the bark of infected citrus trees. These splits, along with thin strips of partially loosened bark, are key indicators of the disease, which can have detrimental effects on the overall health and longevity of citrus plants.

Loose smut is a fungal disease affecting barley, oats, and wheat, characterized by infected heads covered with olive-green spores. This disease can lead to significant losses in crop yield if not properly managed, making it important for farmers to implement preventive measures.

Plant diseases, a symptom refers to objective evidence of disease in plants. These can be visible signs or indications of a plant's abnormality or disorder, helping in the identification and diagnosis of plant diseases. Recognizing symptoms accurately is essential for implementing appropriate treatment measures and maintaining plant health.

Granville wilt, caused by Pseudomonas solanacearum, is a bacterial disease that affects various plants like tobacco, tomato, potato, eggplant, and pepper. It results in symptoms such as stunting, yellowing, wilting of above-ground parts, and decay of roots, turning them black or brown. This disease can have detrimental effects on the affected plants' growth and overall health.

Tobacco mosaic, caused by Tobacco mosaic virus (TMV), is a viral disease that affects plants like tobacco, tomato, and various vegetables and weeds. Its symptoms include a mottled appearance of leaves in a mosaic pattern and can lead to dwarfing of the affected plants. The distinct visual patterns on the leaves make this disease easily identifiable, impacting the plants' growth and productivity.

Late blight of potato is a fungal disease caused by Phytophthora infestans. It leads to the development of water-soaked dark green to black lesions on lower leaves of the potato plant with white mildew at the edge of these lesions. This disease is notorious for its ability to spread rapidly under favorable conditions, causing significant damage to potato crops.

White-pine blister rust, caused by the organism Cronartium ribicola, is characterized by small discolored spindle-shaped cankers surrounded by a narrow band of yellow-orange bark. This disease leads to the formation of blisters that exude secretion followed by bright orange pustules. White-pine blister rust is a significant threat to white pine trees and can cause severe damage to forests where these trees are prevalent.