Question

You have heard about several insectivorous plants that feed on insects. Nepenthes or the pitcher plant is one such example, which usually grows in shallow water or in marsh lands. What part of the plant is modified into a ‘pitcher’? How does this modification help the plant for food even though it can photosynthesize like any other green plant?

Answer 1

Leaf modification

The following are the adaptations:-

*The leaf base is winged.

* Petiole is tendrillar.

* The leaf lamina is modified into the pitcher and it produces digestive juices. The leaf tip is modified into the lid of the pitcher which is colored to attract insects.


Role of modification

*The pitcher plant usually grows in soils with poor nitrogen and phosphorus content.

* Therefore, these plants tend to be insectivorous receiving their nitrogen requirement from the insects that they digest.

* Insects and other prey are attracted to the mouth of the pitcher by the nectar-secreting glands lining the lip of the pitcher.

* The body of the pitcher is very slippery making the insect tumble into the digestive juices that are present inside the pitcher.

* The insects are thus digested by enzymes secreted within the leaf.

Therefore, although the plant can photosynthesise, however, it captures insects for satisfying its nitrogen requirement