 |
| Insectivorous Leaves |
|
| |
| A few plants capture insects and absorb nitrogenous food from their bodies. Such plants are described as insectivorous plants or carnivorous plants. In these plants the leaves are modified for the purpose of capturing insects. |
| |
| In Nepenthes, (pitcher plant) the entire leaf is modified for the purpose of capturing insects. The leaf base is modified into an expanded structure, the petiole is modified into a tendril which holds the lamina in vertical position, the lamina is modified into a pitcher to capture and digest insects and the leaf apex is modified into a lid to attract the insects. |
| |
| In Utricularia (bladder wort), an aquatic plant, the leaf is segmented. Some of the segments are modified to form bladders. Each such bladder is provided with a trap door entrance, which allows small organisms to enter but does not let them go out. |
| |
 |
| |
| fig. 27.39 - Insectivorous Leaves |
| |
| In Drosera (sundew), many hair-like tentacles arise from the circular lamina. These tentacles secrete a sticky juice, which glows in sunlight like dew drops. When an insect alights on the lamina mistaking this juice for honey, all the tentacles bend over the insect and the insect is captured. Ultimately the insect body is digested and absorbed. |
| |
|
| This is a phenomenon where the plant has two types of leaves. This condition is seen in many aquatic plants, such as Limnophylla. In Eucalyptus and Artocarpus, leaves of an immature plant and an adult tree are different .In water plants, the submerged leaves are very much dissected while those above the water level are entire. |
| |
|
| Leaf buds are structures specially meant for vegetative reproduction. These are seen in plants like Bryophyllum or Begonia. In Bryophullum, the leaf buds are seen in the margin. They produce adventitious roots below and shoot system above. As a result many plants may be obtained from one leaf which is planted on the soil surface. |
| |
