In seed biology, vivipary is best defined as germination of the seed or embryo under which of the following conditions?

Introduction:
Seeds usually undergo a period of dormancy and germinate only after they are dispersed and find suitable conditions in the soil. However, in some plants, seeds begin to germinate while they are still attached to the parent plant and enclosed within the fruit. This unusual type of germination is described by a specific term in seed biology. This question asks you to select the definition that correctly matches the term vivipary.

Given Data / Assumptions:
- The term to define is vivipary. - Options describe different germination situations: during storage, within the fruit, above soil and below soil. - We assume common textbook examples such as mangrove plants, where vivipary is clearly visible. - The focus is on the location and timing of germination relative to the parent plant.

Concept / Approach:
Vivipary is derived from Latin words meaning live birth. In plants, it refers to the phenomenon where seeds germinate while still attached to the parent plant, usually inside the fruit. The embryo continues to grow and develops into a seedling or propagule that eventually detaches. This is clearly seen in mangroves like Rhizophora, where long propagules hang from the parent tree. Epigeal and hypogeal germination (cotyledons above or below soil) are different classifications that do not describe vivipary. Germination during dry storage is called preharvest sprouting or seed spoilage, not vivipary.

Step-by-Step Solution:
Step 1: Recall that vivipary in plants is most famously observed in mangrove species. Step 2: In these plants, the seed germinates while still inside the fruit attached to the parent tree, forming a visible seedling. Step 3: Recognise that epigeal and hypogeal germination refer only to whether cotyledons emerge above or stay below soil after sowing. Step 4: Note that germination during storage is usually considered undesirable preharvest sprouting and not classical vivipary. Step 5: Select the option that mentions germination within the fruit on the parent plant as the correct definition of vivipary.

Verification / Alternative check:
Botany and seed technology texts define viviparous germination as a condition in which the embryo grows and breaks out of the seed coat while still attached to the parent plant. The fruits of mangrove species often show long, pencil like seedlings attached to branches, which are called viviparous propagules. These explanations consistently match the option describing germination within the fruit on the parent plant, confirming that as the correct definition.

Why Other Options Are Wrong:
Germination during storage in dry conditions: Usually referred to as preharvest sprouting or deterioration in stored grains; it is not the classical definition of vivipary. Germination with cotyledons emerging above the soil surface: This describes epigeal germination, not specifically vivipary. Germination with cotyledons remaining below the soil surface: This describes hypogeal germination, again different from vivipary.

Common Pitfalls:
Learners sometimes confuse vivipary with epigeal or hypogeal types because all involve germination stages. Another pitfall is to associate vivipary with any early or unusual germination, including storage sprouting. To avoid confusion, always connect vivipary with live birth like germination on the parent plant and remember mangrove examples where seedlings are visibly attached to branches above water before dropping to the mud below.

Final Answer:
Vivipary is defined as Germination while still within the fruit on the parent plant.