AP BIOLOGY

Detailed explanation-1: -When loss of water is more than the rate of absorption or uptake of water by the roots, it leads to wilting because of water stress.

Detailed explanation-2: -When transpiration exceeds water absorption by the roots, the plant dehydrates. This usually happens each day with the plant rehydrating again each night. As the soil dries out this rehydration is not complete, resulting in the plant becoming water stressed (Figure 3).

Detailed explanation-3: -On a hot, dry day (or after several days with no rain or watering), transpiration causes more water to be lost than is coming in, and the water balance within the plant can get thrown off. The dehydrated collapsing cells in the leaves and stems can no longer remain erect, and the plant begins to wilt.

Detailed explanation-4: -If there is excess water loss from plant during transpiration, than is available in soil, the leaf cells lose turgidity and leaves droop down. This is called as wilting of plant. Thus, excessive transpiration causes plants to wilt.

Detailed explanation-5: -Wilting diminishes the plant’s ability to transpire and grow. Permanent wilting leads to plant death. Symptoms of wilting and blights resemble one another. The plants may recover during the night when evaporation is reduced as the stomata closes.