Soil Science MCQ Question and Answer | Agriculture MCQ Question

An inorganically formed sedimentary rock is Gypsum.
Gypsum is a soft sulphate mineral composed of calcium sulphate dihydrate. It is a common mineral, with thick and extensive evaporate beds in association with sedimentary rocks. Deposits are known to occur in strata from as far back as the Archaean eon.

IFFCO (Indian Farmers Fertilizer Cooperative) was formed on 3^rd November 1967 and is headquartered in New Delhi.
It is a multi-state cooperative society and is wholly owned by the cooperative societies of India. Society is engaged in the business of manufacturing and marketing fertilizers.

CEC is cation exchange capability and varies according to the type of soil.
Humus, the end product of decomposed organic matter, has the highest CEC value because organic matter colloids have large quantities of negative charges.
Humus has a CEC two to five times greater than montmorillonite clay and up to 30 times greater than kaolinite clay, so is very important in improving soil fertility.
CEC of humus is 250 - 350.

Potassium is the nutrient element that determines the quality of produce.
Potassium is one of the essential macronutrients for plant growth. It is an activator of dozen of enzymes, such as protein synthesis, sugar transport, N and C metabolism and photosynthesis. Potassium is associated with the movement of water, nutrients and carbohydrates in plant tissue.

The term functional or metabolic nutrient was given by D. J. Nicholas.
There are 20 mineral elements necessary or beneficial for plant growth. Carbon, hydrogen and oxygen are supplied by air and water.
The 6 macronutrients, nitrogen, phosphorus, potassium, calcium magnesium and Sulphur are required by plants in large amounts.
Iron, manganese, boron, molybdenum, copper, zinc, chlorine and cobalt as micronutrients.

Sylvite, Sylvanite, Langbeinite and Glascrite are ore of potash nutrient.
Sylvite or sylvine is potassium chloride in natural mineral form. It forms crystals in the isometric system very similar to normal rock salt.
Sylvanite is a gold: silver ratio and is a metallic mineral with a colour that ranges from a steely gray to almost white.
Langbeinite is a potassium magnesium sulphate mineral. It is a unique source of plant minerals.
Glascrite is formed as an intermediate compound and an ore of potash.

Wet digestion with concentrated acids is the most common sample pretreatment technique, carried out at atmospheric pressure in open systems or higher pressures in a closed vessel by conductive or microwave heating.
In the wet digestion procedure ratio of tri acid mixture is 9 : 3 : 1.

The angle of extinction is the measure between the cleavage direction or habit of a mineral and the extinction. To find this, simply line up the cleavage lines/long direction with one of the crosshairs in the microscope and turn the mineral until the extinction occurs.
By using the angle of extinction, we can identify all of these minerals given in the options Apatite, Muscovite, Augite etc.

Cotton is the crop among the following options that are most tolerant to salty soils.
Salt tolerance is the ability of plants to grow and complete their life cycle on a substrate that contains high concentrations of soluble salt. Plants that can survive on high concentrations of salt in the rhizosphere and grow well are called halophytes.

Chlorites are a group of phyllosilicate minerals common in low-grade metamorphic rocks and altered igneous rocks.
Chlorite belongs to the 2 : 2 type. The typical general formula for chlorite is (Mg, Fe)₃(Si, Al)₄O₁₀(OH)₂ · (Mg, Fe)₃(OH)₆. This formula emphasizes the structure of the group, which is described as TOT-O and consists of alternating TOT layers and O layers.