Agronomy MCQ Question and Answer | Agriculture MCQ Question

Anabena is the principal nitrogen-fixing algal community of blue-green algae. It is found as plankton in shallow water and on moist soil as beadlike or barrel cells and interspersed with enlarged spores.
They form symbiotic relationships with certain plants, such as mosquito fern.

An aquifer is a body of rock or sediment that holds groundwater.
Water potential at aquifers here means the total amount of permanent storage that exists in the aquifers in the form of ground water.
Water potential at the aquifer is nearly 0 bar.

For transplanting a one-hectare area of rice approximately 1000 meter square of the area is sufficient for nursery raising. It is $${\frac{1}{{10}}^{{\text{th}}}}$$ of the total area needed for conventional transplantation of rice.
There are different methods of raising rice seedlings, these are the Wet bed nursery, the Dry bed nursery, the Dapog nursery, etc.

Flocculation is a process where individual clay particles are pulled together.
Dispersion is the act of repellence of the soil particles.
Cohesion is the intermolecular attraction between the molecules of soil particles.
Soil structure is defined by the way individual particles of sand, silt and clay are assembled. Thus this was not correctly matched.

Brix value is a measure of the soluble solids content of a solution.
Brix value can be calculated by dividing the dissolved solids by the sum of the dissolved solid plus water, all multiplied by 100.
$${\text{Bx}} = \frac{{\left( {{\text{Ds}} \times {\text{100}}} \right)}}{{\left( {{\text{Ds}} + {\text{100}}} \right)}}$$
And Brix value of sugar cane is in between 16 - 18.

The Antarctic Blue whale is the largest living animal on the planet.
It weighs up to 4,00,000 pounds and is about 98 feet in length. Its long and slender body can be of various shades of greyish-blue dorsally.
The International Union for conservation of nature has listed blue whales as endangered species as they face numerous man-made threats such as ship strikes, pollution, ocean noise and climate change.

In dwarf wheat variety, sowing depth is related to the length of the coleoptile.
Coleoptile is the cylindrical organs that ensheath the first leaf and shoot apex in the wheat seedlings. It helps in the emergence of the first leaf by protecting it during its passage through the soil.

The soybean is a species of legume native to East Asia and is widely grown for its edible bean. As per the evidence, soybean domestication between 7000 and 6600 BC in China. The history of the development of soybean varieties in India is quite new. The introduction of soybean started in 1960 with trials conducted at Pantnagar and Jabalpur agricultural Universities.

Saccharum officinarum is a species of sugarcane is referred to as noble cane. Its stalks are vigorous and long with low fibre content, thick barrel-shaped internodes, large soft-rinded juicy stalks, and rich in sucrose.

Lint in the cotton seed is the long- fibres in the cotton boll. Cotton lint refers to the fibrous coat that covers the cotton seeds, it is ginned cotton.
The ratio of cotton seed to lint is 2 : 1.