Question

Usually, rain disrupts pollination in the flowers; however, in certain crops, it favors pollination. In which of the following crops, rain favors pollination?

• A. Cardamom
• B. Cinnamon
• C. Pepper
• D. Nutmeg

Hint:

Black pepper (Piper nigrum) is a classic example of a crop that exhibits hydro-pollination or rain-facilitated self-pollination, where rainwater running down the spikes transfers pollen to the stigmas.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Pollination is the transfer of pollen grains from the male anther to the receptive female stigma.
While abiotic factors like wind (anemophily) and water (hydrophily) typically facilitate pollination, heavy rainfall usually disrupts pollination in most land plants by washing away pollen grains, damaging delicate floral structures, or preventing insect vectors from flying.
However, some specific crop species have adapted to utilize rain or water droplets to facilitate the transfer of pollen within the flower, a process sometimes referred to as rain pollination or splash pollination.

Step 2: Detailed Explanation:
Black pepper (Piper nigrum), a woody climbing vine native to the humid tropics, relies significantly on rain to achieve successful pollination:
1. Floral Structure: Black pepper spikes carry numerous small, closely packed, bisexual (hermaphrodite) flowers that lack prominent petals or sepals.
2. Mechanism of Rain Pollination: Water droplets from rain run down the vertical spikes, washing the sticky pollen grains directly from the dehiscing anthers onto the receptive stigmas located immediately below or adjacent to them on the same spike.
This water-mediated transfer ensures high self-pollination rates under the humid, wet conditions of the monsoonal climates where black pepper natively thrives.
3. Contrast with other crops: In other spices like Cardamom (A), Cinnamon (B), and Nutmeg (D), pollination is heavily dependent on biotic insect vectors (like bees, thrips, or beetles).
In these crops, rain can depress pollinator activity and physically wash away pollen or nectar, leading to poor fruit set.
Therefore, pepper is the crop where rainfall acts as a positive facilitator of pollination.

Step 3: Final Answer:
Rain favors pollination in black pepper, which corresponds to option (C).