Plant Pathology MCQ Question and Answer | Agriculture MCQ Question

Khaira disease in rice is caused due to deficiency of Zinc.
Khaira disease Of Rice is a micro-nutritional (Zn) deficiency characterized by the presence of dusty brown patches on leaves which ultimately undergo necrosis. This is one of the most common diseases in rice.
Treatment of rice seed with 0.4% ZnSO₄ before sowing or of seedlings before transplanting gives control. Spraying with 0.4% ZnSO₄ + 2% urea on the appearance of the symptoms is useful.

Nepoviruses are Bipartite.
Nepovirus is a genus of viruses in the order Picornavirales, in the family Secoviridae, and the subfamily Comovirinae. Plants serve as natural hosts. There are 40 species in this genus.
The genus Nepovirus includes viruses that are transmitted by nematodes with polyhedral particles. Typical nepoviruses have a broad host range, a single coat protein, and a bipartite single-stranded RNA genome and are transmissible through seed.

The milky water of green coconut is a Liquid endosperm.
Coconut Endosperm is the liquid endosperm of green coconuts Cocos nucifera.
Coconut water is the clear liquid inside coconuts. In early development, it serves as a suspension for the endosperm of the coconut during the nuclear phase of development.

Katan is regarded as the father of soil solarization.
Soil solarization is a hydrothermal process of disinfecting the soil of pests, accomplished by solar power and is relatively a new soil disinfestation method, first described in extensive scientific detail by Katan in 1976.
It is a non-chemical environmentally friendly method for controlling pests using solar power to increase the soil temperature to levels at which many soil-borne plant pathogens will be killed or greatly weakened.

Mycoplasma cell membranes have Three layers.
Mycoplasmas (class Mollicutes) are the smallest and simplest self-replicating bacteria.
In Mycoplasma organisms the membrane seems to be composed of two electron-dense layers with a less dense layer in between this three-layered structure corresponds to the 'unit membrane' which covers cells and organelles of various origins.

The N in all fertilizers comes from Air.
For nitrogen-based fertilizers, the largest product group, the process starts by mixing nitrogen from the air with hydrogen from natural gas at high temperatures and pressure to create ammonia.
The Haber process produces ammonia (NH₃) from methane (CH₄) (natural gas) gas and molecular nitrogen (N₂) from the air.

Enzymes of the Krebs cycle occur in the mitochondrial matrix except one that is Succinate dehydrogenase which is attached to inner mitochondrial membrane.
Succinate dehydrogenase is an enzyme complex, found in many bacterial cells and the inner mitochondrial membrane of eukaryotes.
It is the only enzyme that participates in both the citric acid cycle and the electron transport chain. The reactions occur in the inner mitochondrial membrane by coupling the two reactions together.

4 rings are found in the flagella structure of Gram-ve bacteria.
Gram-negative organisms have four such rings: the L ring associates with the lipopolysaccharides, the P ring associates with the peptidoglycan layer, the M ring is embedded in the plasma membrane, and the S ring is directly attached to the plasma membrane.

The proportion of the plant population affected by a disease is known as Disease Intensity.
Disease intensity is a general term used to denote amount of disease, commonly expressed as either disease incidence (proportion of the total number of plants that are infected) or disease severity (proportion of total plant area that is infected).
The disease severity is estimated by a rater as a value on the interval scale and has been used to determine a disease severity index (DSI) on a percentage basis, where DSI (%) = [sum (class frequency × score of rating class)] / [(total number of plants) × (maximal disease index)] × 100.

Mitochondria are sites of Oxidative phosphorylation.
The breakdown of carbohydrates or fats is derived from oxidative phosphorylation, which takes place within mitochondria.
As the production of reactive oxygen species by these proton-pumping complexes is greatest at high membrane potentials, it has been proposed that mitochondria regulate their activity to maintain the membrane potential within a narrow range that balances ATP production against oxidant generation.