What is the stomatal density on the upper and lower epidermis of hibiscus and colacasia leaves?

Does time affect the stomata density of a leaf? e.g young leaves, old leaves.?

• We collected the leaves a month after we took the API index. It was at a rural area, near a beach. It was a beach resort actually. We collected the leaves a month later because of transport problems to the area. We would like to know if the stomata of the leaves is affected. We are doing a project with the title Stomata Density vs API Index.

• Answer:

  Stomatal index( Number of stomata per unit area of a leaf) is always constant for a given species. It differs only between upper and the lower epidermis of that leaf. The age of a leaf has no bearing on the stomatal index . The number of stomata per unit area on the leaf you are talking about will not change even if you collect them to day or a month later. If two plants of the same species exist in vastly different ecological situation only then the number may vary.