Pressure flow theory was formulated by

Explanation

The pressure-flow hypothesis was formulated by Ernst Münch in 1930.The pressure flow hypothesis, also known as the mass flow hypothesis, is the best-supported theory to explain the movement of sap through the phloem. Glucose generated by photosynthesis at the source is converted to sucrose which is moved to the phloem sieve tube cells through the companion cell by active transport. The remaining transport in the phloem is carried out by the differences in the osmotic pressure, which facilitates the transport from higher pressure to lower pressure regions of the sink. Again by active transport, the sucrose is transported from phloem to the cells of the sink where it will be stored for a long.