Agronomy MCQ Question and Answer | Agriculture MCQ Question

Arhar also known as Pigeon pea or red gram, is a very old crop in our country. It is a leguminous crop, highly proteinaceous.
Plume moth, Mod borer, and Leaf hopper are the serious insect pest of arhar.
A plume moth is a brown-colored moth with fringed or plume like wings.
Pod borer is the important insect pest of chick pea and it damages crop yield loss.
A leafhopper is the minute insects are plant feeders that suck plant sap from grass, shrub and trees.

Let's break down this question about plant growth measurements!

First, what do these abbreviations mean?
* RGR: Relative Growth Rate - How much a plant grows per unit of existing plant material per day.
* CGR: Crop Growth Rate - How much a plant community (like a field of crops) grows per unit area per day.
* LAI: Leaf Area Index - The total leaf area per unit ground area.
* LAR: Leaf Area Ratio - The leaf area per unit of total plant dry weight.

Now, let's consider realistic values:
* RGR = 5 g/g/day: This would mean a plant *doubles* its size *five times* each day! This is incredibly fast and not generally possible for most plants. So, it is not a realistic value.
* CGR = 5 g/m²/day: A crop growing 5 grams of biomass per square meter each day is quite reasonable and achievable, depending on the crop and growing conditions.
* LAI = 5: An LAI of 5 means there are 5 square meters of leaves for every square meter of ground. This is a common and realistic value for many crops at their peak growth.
* LAR = 5 cm²/g: This indicates that for every gram of plant material, there are 5 square centimeters of leaf area. This value is realistic and falls within the normal range for plants.

Therefore, the answer is A: RGR = 5 g/g/day, because it represents an unrealistically high growth rate.

Transfer of heat in soil mainly occurs by the process of conduction. It is the process by which heat energy is transmitted through collisions between neighboring atoms or molecules. As we know soil is made up of particles, atoms and molecules, closely together to transfer heat.

Castor is a species of perennial flowering plant in the spurge family. It requires a hot, dry climate with an annual rainfall of 500 - 800 mm, of which 500 - 600 mm is needed during the first 3 months of crop growth. High temperatures above 41 degree Celsius at a flowering time even for a short period result in the blasting of flowers in Castor.

Single Super phosphate SSP is the first chemical fertilizer, it contains 3 major plant nutrients namely phosphorus, Sulphur, and calcium along with traces of micro-nutrients.
It contains 14.5% of phosphorus, 12% of Sulphur and 21% of Calcium.

IRGA stands for Infra-Red Gas Analyser and measures trace gases by determining the absorption of an emitted infrared light source through a certain air sample.
The concept behind the technology is based on the amount of light absorbed by the air.

In gramineous plants, the first leaf below the inflorescence is called the flag leaf. The flag leaf is the last to emerge, which indicates the transition from the growth of the plant to grain production.
Photosynthesis in these leaves provides the maximum of carbohydrates required for grain filling. Contribution of flag leaf in photosynthesis is about 52%.

The optimum plant population or density of a crop plantation is the arrangement per unit area that allow crops to exploit resource optimally and produce high yields.
The optimum plant population per hectare for cotton has estimated as 50,000 - 80,000.
India has about 37% of the world's area under cotton cultivation and is the largest producer of cotton in the world accounting for 22% of total production.

Cadmium is the natural element found in tiny amounts in air, water, soil and food.
Dumping of sewage sludge into the soil leads to soil pollution and various heavy metals like cadmium, lead, etc present in waste water amend in soil and cause contamination of soil also to the foods and crops grown on that soil. This makes soil potentially toxic to the plants.

The optimum cardinal temperature for any plant is the temperature range within which the seeds of a particular species can germinate.
The optimum cardinal temperature for germination of rice seeds is 20°C - 25°C.