Plant Pathology MCQ Question and Answer | Agriculture MCQ Question

Micronutrient absorbed by foliage is Zinc.
Zinc is an important component of various enzymes that are responsible for driving many metabolic reactions in all crops. Growth and development would stop if specific enzymes were not present in plant tissue.
Spray the plant with kelp extract or a micro-nutrient foliar spray that contains zinc. Foliar sprays provide zinc for plants where it is needed most and the rate at which they recover is amazing.

A totipotent cell means an undifferentiated cell capable of developing into a system or entire plant.
A single cell can divide and produce all the differentiated cells in an organism, including extraembryonic tissues.
Totipotent cells formed during sexual and asexual reproduction include spores and zygotes.

In plants buckling, puckering and blistering symptoms are produced by Viruses.
Plant viruses are made up of a strand of nucleic acid (DNA or RNA) surrounded by a protein sheath.
Local symptoms are physiological or structural changes within a limited area of host tissue, such as leaf spots, galls, puckering, buckling and cankers.
Symptoms of virus infection include necrotic spots, abnormal dark green and light green mosaic and mottling of leaves, growth distortion, stunting, ring patterns or bumps on plant foliage, and abnormal flower coloration and formation.

The perfect stage of Colletotrichum falcatum (causes red rot of sugarcane) is Glomerella tucumanensis.
Sugarcane (Saccharum spp.) is a commercially important crop, vulnerable to fungal disease red rot caused by Colletotrichum falcatum.
The pathogen attacks sucrose accumulating parenchyma cells of cane stalk leading to severe losses in cane yield and sugar recovery.

Vanderplank gave the biochemical basis of Gene for Gene hypothesis.
The gene for gene hypothesis states that for each gene controlling resistance in the host, there is corresponding gene controlling pathogenicity in the pathogen.
The resistance of the host is governed by dominant genes and virulence of pathogen is by recessive genes.

Nitrogen fixation is the role of molybdenum.
The molybdenum nitrogenase is responsible for most biological nitrogen fixation, a prokaryotic metabolic process that determines the global biogeochemical cycles of nitrogen and carbon.
Molybdenum is utilized by selected enzymes to carry out redox reactions. Enzymes that require molybdenum for activity include nitrate reductase, xanthine dehydrogenase, aldehyde oxidase and sulphite oxidase.

The powdery mildew of wheat is associated with fungi Erysiphe graminis sp. tritici.
Wheat powdery mildew caused by fungus Erysiphe polygoni, f. sp. tritici is one of the most prevalent wheat diseases in the world.
Powdery mildew is a white powdery mass that appears on the leaves and twigs of the plants in the initial stage; later on, the whole plant is covered with the whitish powder.

Rust of linseed and flax (autoecious rust) is caused by Melampsora lini.
The pathogen is an obligate biotroph meaning that each stage of its cycle is dependent on having a living host. The direction between reproducing sexually or asexually is dependent on the availability of a host.
Sexually, the life cycle starts when basidiospores land on flax leaves and form pycnium during December and through January.

Victoria blight epidemic devastated Oat crops in 1946.
Cochliobolus victoriae is a fungal plant pathogen. It caused the disease called "victoria blight" affecting oats and similar grains.
Symptoms include stem weakening, seedling death, leaf damage, and premature ripening of seeds.
Victorian oat varieties have resistance to crown rust, which is considered one of the most important diseases in oats. In the 1940s, Victoria oats were very popular among American oat farmers because of this crown rust resistance.

Night soil contains 5.5% N.
Night soil is nothing but Human excreta, collected from cesspools, privies, pail closets, pit latrines, and septic tanks. It was produced as a result of a sanitation system in areas without sewer systems or septic tanks and sold as a fertilizer.
Night soil is very rich in essential plant nutrients. It contains about 5.5% Nitrogen, along with other compounds like phosphorus, potassium, etc.