Genetics And Plant Breeding - Study Mode

[#251] For transferring the disease resistance gene from wild variety to the most suitable agronomically desirable variety the suitable method is
Correct Answer

(B) Back cross

Explanation

Solution: For transferring the disease resistance gene from the wild variety to the most suitable agronomically desirable variety the suitable method is Back cross. Backcrossing is the plant breeding method most widely used to incorporate one or a few genes into an elite or adapted variety. In this method, the parent used for backcrossing has a large number of desirable attributes but lacks a few characteristics.

[#252] The growth regulator that retards ageing of plant organ is
Correct Answer

(C) Cytokinin

Explanation

Solution: The growth regulator that retards ageing of plant organs is Cytokinin. cytokinins are an important regulatory factor of plant meristem activity and morphogenesis, with opposing roles in shoots and roots. It promotes cell division and increases cell expansion during the proliferation and expansion stages of leaf cell development, respectively.

[#253] Consider the following statements? The back cross method of breeding can be used for 1. Intervarietal transfer of simple inherited characters. 2. Intergeneric transfer of highly heritable characters. Which of the statements given above is/are correct?
Correct Answer

(A) Only 1

Explanation

Solution: The back cross method of breeding can be used for the Intervarietal transfer of simple inherited characters, this statement given above is correct. Backcrossing is the plant breeding method most widely used to incorporate one or a few genes into an elite or adapted variety. Backcross breeding enables breeders to transfer a desired trait such as a transgene from one variety (donor parent, DP) into the favored genetic background of another (recurrent parent, RP).

[#254] In cotton, example of durable resistance includes resistance to
Correct Answer

(D) All of these

Explanation

Solution: In cotton, an example of durable resistance includes resistance to Bacterial blight, leaf curl and jassids. Bacterial blight is a widespread soybean disease that is most common during cool, wet weather. This disease usually occurs at low levels that don't result in yield loss. Curling leaves can be caused by many problems, including insect damage, disease, abiotic disorders, or even herbicides. Several insect pests cause leaves to curl when they suck plant juices of new or young leaves that are still growing. Cotton jassids are sap-sucking pests of cotton and several other host plants.

[#255] The primary acceptor of CO 2 - in C 3 -plants is
Correct Answer

(C) RuBP

Explanation

Solution: The primary acceptor of CO 2 in C 3 plants is RuBP. Ribulose 1,5 -bisphosphate (RuBP) is an organic substance that is involved in photosynthesis, notably as the principal CO 2 acceptor in plants. It is a colourless anion, a double phosphate ester of the ketopentose (ketone-containing sugar with five carbon atoms) called ribulose. During photorespiration, RuBP combines with O 2 to become 3-PGA and phosphoglycolic acid.