Rape is an important oil-bearing crop and very sensitive to drouhgt. Ultrastructural changes occurred in the mesophyll cells of rape plants which grow in dry condition were observed. In the mesophyll cells a tubuli-vesicular Structure can be found when the drought is developed. But the Structures were never occurred in the cells of control plants. At the beginning of drought the structures appeared near to plasma membrane then on the tonoplast membrane of central vacuoles, and connected with the membrane. T...