Step 1: Understanding the Question:
The question asks for the standard nursery technique used to break "endogenous dormancy," which is a type of physiological dormancy residing within the embryo or the internal tissues of a seed. Step 2: Detailed Explanation:
• Seed dormancy is classified into two main types: exogenous (due to the seed coat) and endogenous (due to the embryo). Endogenous dormancy often requires a period of specific environmental triggers to initiate the chemical changes necessary for germination.
• Cold stratification is the process of exposing seeds to cold, moist conditions for a specific duration. This mimics the natural winter conditions that many temperate seeds must undergo before they can sprout in the spring.
• During cold stratification, complex biochemical processes occur within the seed, such as the degradation of germination inhibitors (like abscisic acid) and the synthesis of growth promoters (like gibberellins).
• Hot water treatment and sandpaper piling (scarification) are typically used for exogenous dormancy, where the goal is to soften or breach a hard, impermeable seed coat. Alternate wetting and drying is often used for teak or hard-coated tropical seeds to induce physical weathering.
• For seeds with an immature or physiologically dormant embryo, cold stratification is the primary scientific recommendation to ensure uniform and rapid germination. Step 3: Final Answer:
Cold stratification is recommended for breaking down endogenous dormancy.
Was this answer helpful?
0
0
Top ICAR AIEEA Forestry Agroforestry Silviculture Questions
