Plant Pathology MCQ Question and Answer | Agriculture MCQ Question

a. Hot water is the extractant of Boron.
Boron is extracted with near-boiling deionized water on a heating block. Boron in the extract is reacted with curcumin to form an orange-coloured complex. The concentration of B is determined colorimetrically or by UV-Vis spectrophotometry. Each chemical compound should be treated as a potential health hazard.
b. Alkaline KMnO₄ is the extractant of Nitrogen.
The easily hydrolyzable and oxidisable fractions of organic nitrogen present in a soil sample can be extracted using alkaline KMnO₄ - a mild oxidizing agent.
c. 0.15% Cacl₂ solution is the extractant of Sulphur.
0.15% CaCl₂ extracted S in the range of 13.00 to 26.50 mg kg^-1, with a mean value of 19.26 mg kg^-1. The lowest amount of S (mean value of 8.21 mg kg^-1) has been extracted by 0.001 M HCl with a range of 3.75 to 14.25 mg kg^-1.

A. tritici is the seed gall nematode.
Anguina tritici commonly referred to as wheat seed gall nematode, is the cause of ear-cockle disease.
It was the first plant-parasitic nematode to be described in the scientific literature in 1743. Its host range includes wheat, triticale, rye, and related grasses; the primary host is wheat.

MLO was first discovered by Doi.
Mycoplasma-like organisms (MLO), pathogens of the plant yellows diseases, as a model of coevolution between prokaryotes, insects and plants.
Phytoplasmas, a large group of plant-pathogenic, phloem-inhabiting bacteria were discovered by Japanese scientist Doi in 1967.
They are transmitted from plant to plant by phloem-feeding insect hosts and cause a variety of symptoms and considerable damage in more than 1,000 plant species.

Blood meal contains 13 - 20% N.
A blood meal is extremely rich in Nitrogen. It contains about 13 - 20% Nitrogen, 1% phosphorous, and 0.6% of potassium. It is a dry, inert powder made from blood, used as a high-nitrogen organic fertilizer, non-synthetic, and high protein animal feed.
A blood meal is composed of protein mostly, small amounts of fats, and ash. It usually comes from cattle or hogs as a slaughterhouse by-product.

The most widely used fungicide for smut fungi is Vitavax.
Vitavax Power (Carboxin 37.5% + Thiram 37.5% DS) is a broad spectrum, dual-action (systemic and contact) fungicide which controls seed and soil-borne diseases, and also acts as a plant growth stimulant.
It is used as a seed treatment and is effective against damping-off diseases caused by Rhizoctonia and against the various smuts of grain crops.

IFFCO was formed in the year of 1967.
Indian Farmers Fertiliser Cooperative Limited, also known as IFFCO, is a multi-state cooperative society. IFFCO is wholly owned by the Cooperative Societies of India. Society is engaged in the business of manufacturing and marketing fertilizers.
IFFCO is headquartered in New Delhi, India. Starting in 1967 with 57 member cooperatives, it is today the biggest co-op in the world by turnover on GDP.
With the introduction of a multi-agency approach by the Government of India in the distribution of fertilizers in 1967, the private trade also entered the field of fertilizer distribution.

Urea has a chemical composition of Co(NH₂)₂.
Urea, also known as carbamide, is an organic compound with the chemical formula CO(NH₂)₂. This amide has two amino groups (–NH₂) joined by a carbonyl functional group (–C(=O)–). It is thus the simplest amide of carbamic acid.
It is a colorless, odorless solid, highly soluble in water, and practically non-toxic. A nitrogen-containing organic compound found in urine and other body fluids. Urea is synthesized from ammonia and carbon dioxide. Urea can be used as fertilizer.

The ascus is a sexual fruit of ascomycetes having a globose shape but no ostile (opening) and is known as Chleistothecia.
An ascus is the sexual spore-bearing cell produced in ascomycete fungi. Each ascus usually contains eight ascospores (or octad), produced by meiosis followed, in most species, by mitotic cell division.
Ascospores are nonmotile, usually single-celled, but not infrequently may be coenocytic (lacking a septum), and in some cases coenocytic in multiple planes.

The phosphorus content as P is the plough layer of one hectare of soil containing 0.1% P₂O₅ is 860 kg.

Most plants obtain nitrogen from the soil in the form of Nitrate.
Nitrate is the form of nitrogen most used by plants for growth and development. Nitrate is the form that can most easily be lost to groundwater.
Ammonium taken in by plants is used directly in proteins. This form is not lost as easily from the soil.