Question

Artificial ripening of fruits/banana is accomplished by treatment of-
a. Sodium chloride
b. IAA
c. Ethylene gas
d. Kinetin

Answer 1

Hint: A major plant hormone that influences various processes in plant growth, development, and biotic and abiotic stress response. It is also used elegantly in agricultural fields.

Complete answer:
> Option A is incorrect. As salts are dissolved in water, the sodium and chloride ions detach. The dissolved sodium and chloride ions can displace other mineral nutrients in the soil in high concentrations. Instead of required plant nutrients such as potassium and phosphorus, plants then consume chlorine and sodium, leading to deficits.

> Option B is incorrect. IAA is the predominant auxin in plants, controlling growth and developmental processes such as cell division and elongation, tissue differentiation, apical dominance, and light, gravity, and pathogen responses. Roots are most vulnerable to level IAA variations.

> Option C is correct. In most plants the plant hormone ethylene is a salinity combatant. Ethylene is used to control the growth and development of plants, and adapted to stress. Ethylene is a plant hormone sometimes called a maturing hormone, since it is responsible for fruit ripening. Ripening of the fruit is followed by an increased respiration rate. It inhibits division among cells. Used in gaseous form to accelerate the ripening process of fruits such as bananas.

> Option D is incorrect. The name kinetin because of its ability to trigger cell division, provided the medium produced auxin. Kinetin is also used to promote callus formation (in association with auxin) and to regenerate callous shooting tissues (with lower dose of auxin) in plant tissue culture.

Hence, The correct answer is option (C).

Note: The impact of ethylene gas on fruit is a resulting change in texture (softening), colour, and other processes. Thought of as an ageing hormone, ethylene gas not only affects fruit maturation but can also cause plants to die, usually when the plant gets damaged in some way.