Plant Pathology MCQ Question and Answer | Agriculture MCQ Question

For the first time, T. J. Burrill reported that a plant disease (fire blight of pear) was caused by a bacterium (Erwinia amylovora) in 1882.
The first studies on bacteria as plant disease agents were carried out by T. J. Burril in 1878 and concerned the fire blight disease of apples and pears, caused by Erwinia amylovora.
Fire blight is a contagious disease affecting apples, pears, and some other members of the family Rosaceae. It is a serious concern to apple and pear producers.
The causal pathogen is Erwinia amylovora, a Gram-negative bacterium. It is a short rod with rounded ends and many peritrichous flagella.

Rock phosphate is a suitable fertilizer for Acidic soils.
Rock phosphate (RP) is an important natural source of P and is used as raw material for the production of chemical phosphatic fertilizers.
The direct application of RP has been found suitable for acidic soils as low pH helps to solubilize the RP and increases the available form of P to the plants.
Use of phosphate rock is not usually recommended when the soil pH exceeds 5.5.

Perisperm is remains of nucellus.
Perisperm is a nutritive tissue of a seed derived from the nucellus and deposited externally to the embryo sac.
The nucellus is the central and chief part of a plant ovule that encloses the female gametophyte.

Basidiospores of wheat black rust germinate on Barbery.
A basidiospore is a reproductive spore produced by Basidiomycete fungi, a grouping that includes mushrooms, shelf fungi, rusts and smuts.
Basidiospores typically each contain one haploid nucleus that is the product of meiosis, and they are produced by specialized fungal cells called basidia.
Basidiospores infect young leaves of common barberry (Berberis vulgaris) or other susceptible Berberis, Mahonia, or Mahoberberis species or cultivars.

Fructose 1 : 6 biphosphate splits into two triose phosphates by enzyme Aldolase.
Aldolase, is an enzyme catalyzing a reversible reaction that splits the aldol, fructose 1,6-bisphosphate, into the triose phosphates dihydroxyacetone phosphate (DHAP) and glyceraldehyde 3-phosphate (G3P).

Absence of sequence homology does not hold well for virusoids.
Sequence homology is the biological homology between DNA, RNA, or protein sequences, defined in terms of shared ancestry in the evolutionary history of life.
Inference of homology from protein sequences provides an essential tool for analyzing protein structure, function and evolution.
Virusoids are circular single-stranded RNA. These are essentially viroids that have been encapsulated by a helper virus coat protein, also they are dependent on viruses for replication and encapsidation.

Tyndallization consists of heating the substance at 100°C.
Tyndallization is a process from the nineteenth century for sterilizing substances, usually food, named after its inventor John Tyndall, that can be used to kill heat-resistant endospores.
Tyndallization essentially consists of heating the substance to boiling point (or just a little below boiling point) and holding it there for 15 minutes, three days in succession.

A 5-carbon compound of Krebs cycle is a key compound in nitrogen metabolism. It is α-Ketoglutaric acid.
The Krebs cycle is present in every cell that uses oxygen to produce energy. This metabolic pathway is used as an anabolic cellular principle but also in the presence of catabolism.
α-Ketoglutaric acid (2-oxoglutaric acid) is one of two ketone derivatives of glutaric acid. It is the keto acid produced by deamination of glutamate, and is an intermediate in the Krebs cycle.

The pore size of HEPA filters of LAI (in μ) is 0.3.
HEPA filter, also known as high-efficiency particulate absorbing filter and high-efficiency particulate arrestance filter, is an efficiency standard of air filters.
HEPA filters are composed of a mat of randomly arranged fibers. The fibers are typically composed of polypropylene or fiberglass with diameters between 0.5 and 2.0 micrometers.
HEPA air filter must remove from the air that passes through 99.97% of particles whose diameter is equal to 0.3 μm, with the filtration efficiency increasing for particle diameters both less than and greater than 0.3 μm.

The technique used for maintenance and preservation of Trichoderma is Soil preservation.
Fungi belonging to the genus Trichoderma are used as successful plant growth enhancers, biostimulants, biofertilizers, and as effective biocontrol agents against various pathogens.
Trichoderma is stored by a long term storage method in envelopes kept in the container with a small amount of desiccant at -20°C.