Overview

During the first half of the twentieth century, several areas of plant science or botany were particularly active fields of research. There was an increase in work on plant physiology, on how plant tissues function, and on the biochemistry of plants. There was also a great deal of research on photosynthesis, on how plants use the energy of the sun to make sugar; several plant hormones that controlled growth and development were identified; and photoperiodism, the control of plant processes by day length, was discovered.

As ecology, the study of relationships among species and between organisms and the environment, emerged as a new discipline, botanists investigated how plant communities change over time and how climate affects plant characteristics and community structure. Specialized surveys of the plants in particular geographic areas were also undertaken. In addition, older botanical fields still flourished with work continuing...