Transpiration

• Water loss is a main cause of deterioration because it results not only in direct quantitative losses (loss of salable weight), but also in appearance (wilting and shriveling), textural quality (softening, flaccidity, limpness, loss of crispness and juiciness) and nutritional quality.
• The main sites of water loss in harvested organs are stomata, cuticle, lenticels, trichomes and detached sites.
• Stomata are the main passageway for the loss of water and exchange of air for respiration.
• The leaves have more number of stomata than other parts.
• Some of the leaves have more than 10,000-stomata/square centimeter.
• More number is present in lower surface of leaves.
• Immature leaves, fruits and stem have more number of stomata as compared to matured ones, which partially explains why immature organ deteriorate faster.
• As the plant organ matures the deposition of cuticular layer covers some of the stomata. The number of stomata also varies with the type of plant leaves, its location etc.