Question

Which of the following is not an inhibitory
substance governing seed dormancy?​

Answer 1

Answer:

Seed dormancy is an evolutionary adaptation that prevents seeds from germinating during unsuitable ecological conditions that would typically lead to a low probability of seedling survival.[1] Dormant seeds do not germinate in a specified period of time under a combination of environmental factors that are normally conducive to the germination of non-dormant seeds.[2]

An important function of seed dormancy is delayed germination, which allows dispersal and prevents simultaneous germination of all seeds. The staggering of germination safeguards some seeds and seedlings from suffering damage or death from short periods of bad weather or from transient herbivores; it also allows some seeds to germinate when competition from other plants for light and water might be less intense. Another form of delayed seed germination is seed quiescence, which is different from true seed dormancy and occurs when a seed fails to germinate because the external environmental conditions are too dry or warm or cold for germination.[3]

Many species of plants have seeds that delay germination for many months or years, and some seeds can remain in the soil seed bank for more than 50 years before germination. Some seeds have a very long viability period, and the oldest documented germinating seed came from a study done from tissue buried in Siberian permafrost. Seeds of silene stenophylla, was estimated to be 31,800 years old and researchers regenerated the plant successfully.[4]

Answer 2

Question - Which of the following is not an inhibitory substance governing seed dormancy?

(1) Gibberellic acid

2) Abscisic acid

(3) Phenolic acid

(4) Para-ascorbic acid

Answer - Correct option is (1) Gibberellic acid.

• Gibberellic acid or Gibberellin is one of the plant hormones that has inducing effect on plants.
• The hormone is responsible for promoting growth of cells along with its elongation.
• Gibberellin is also responsible for seed germination and formation of seedless fruits.
• Gibberellic acid helps in germination by promoting growth of embryo and inducing formation of hydrolytic enzymes.