Viviparous germination of seeds occurs in

Question

Accepted Answer

Viviparous germination is a phenomenon where the seed germinates while still attached to the parent plant and nourished by it. This is a specialized adaptation found in certain plants, particularly those growing in challenging environments.

Here's a detailed explanation:

**Justification for Option 1 (Rhizophora):**
Rhizophora, commonly known as a mangrove plant, is a classic example of a species that exhibits viviparous germination. Mangroves grow in intertidal zones, characterized by saline water, anoxic (oxygen-deficient) soil, and tidal fluctuations. In such an environment, if seeds were to drop and germinate on the ground immediately, they would likely be washed away by tides or struggle to establish in the harsh conditions.

To overcome these challenges, Rhizophora seeds germinate while still on the parent tree. The embryo develops, and the radicle and hypocotyl elongate significantly, forming a long, spear-like structure called a propagule. This propagule remains attached to the parent plant, drawing nutrients, until it reaches a certain size and maturity. Once mature, the propagule detaches from the parent plant and, due to its elongated and heavy structure, can either stick into the soft mud below the parent plant or float horizontally for some time before eventually rooting in a suitable location. This pre-germination on the parent plant gives the seedling a head start, increasing its chances of survival and establishment in the harsh mangrove environment.

**Why other options are incorrect:**

*   **Option 2 (Mango):** Mango (Mangifera indica) exhibits typical seed germination, which occurs *after* the seed has been dispersed from the parent plant and provided with suitable conditions (moisture, temperature, light). The embryo develops within the seed coat, and germination begins once the seed is planted in the soil, not while it's still attached to the fruit on the tree.

*   **Option 3 (Potato):** Potato (Solanum tuberosum) primarily reproduces vegetatively through tubers (modified stems). While potatoes do produce flowers and can form true seeds, these seeds are not viviparous. If viable seeds are produced, they would germinate in the soil after dispersal, similar to most other angiosperms, and not while still attached to the parent plant.

*   **Option 4 (Sugarcane):** Sugarcane (Saccharum officinarum) is also primarily propagated vegetatively using stem cuttings (setts). Although sugarcane can produce seeds, they are often sterile or have low viability. When viable seeds are produced, they germinate in the soil after dispersal, not while still attached to the parent plant. Vivipary is not a characteristic of sugarcane seed germination.