Agronomy - Study Mode

[#996] The intercropping of maize and soybean leads to maximisation returns in comparison to mono cropping of maize or soybean. Which one of the following describes the enterprise relationship leading to higher returns of maize and soyabean?
Correct Answer

(B) Complementary relation

Explanation

Solution: Intercropping is the most sustainable practice and is considered to be an environmentally sound and economically advantageous cropping system. Maize is mostly intercropped with legumes as it provides shade to legume species as they are smaller in size in comparison to maize plants. Thus intercropping of maize and soybean are complementary relations, as both complement each other.

[#997] Humus is an example of
Correct Answer

(B) Organic colloids

Explanation

Solution: Humus is dark organic matter present in fertile nutrient rich soil. It is an example of organic colloids, which means it is a mixture of tiny organic matter that cannot decay further or that are resistant to decay. Humus significantly affects the bulk density of soil and contributes to its retention of moisture and nutrients.

[#998] Top cross is produced by crossing a single cross (A × B) with an
Correct Answer

(A) Open pollinated variety

Explanation

Solution: The top cross means the first generation of the cross, a single cross (A × B) with an open pollinated variety. Whereas a single cross is crossing between two inbreds or varieties. Hence, A and B are inbred lines or simple hybrids.

[#999] Which is not a chelating compound?
Correct Answer

(B) CDMA

Explanation

Solution: A chelating agent is a chemical compound that reacts with metal ions to form stable, water soluble metal complexes. EDTA – Ethylenediamine tetraacetic acid is a chelating agent. EDDHA – Ethylenediamine-N, N'-bis (2-hydroxyphenyl acetic acid) is also a chelating agent. HEDTA – Hydroxyethylenediaminetriacetic acid. It can also chelate to form salts. Thus, CDMA is a nonchelating agent.

[#1000] High yielding dwarf varieties of wheat were developed by
Correct Answer

(C) Dr. Norman Borlaug

Explanation

Solution: Dr. Norman Borlaug, genetics, plant pathologist and Nobel prize winner, developed the dwarf variety of wheat in mid 1940 - 50 to increase wheat yields and make the country self-sufficient in food production.