Growth and development of plants are influenced by several environmental factors including light. However, light causes several responses other than photosynthesis. These responses greatly influence the course of plant development and the final plant appearance. They are photomorphogenetic responses. For example, the seeds of many plants do not germinate unless they are exposed to light. Germination of seeds in light [...]
The following points highlight the three main types of plants that respond to photoperiodism. The types are: 1. Short Day Plants 2. Long Day Plants 3. Day Neutral Plants. Type # 1. Short Day Plants: For flowering of short day plants, the day length must not exceed a certain critical value, the day length required is less than a certain [...]
The following points highlight the five main types of plant growth regulators. The types are: 1. Auxins 2. Gibberellins 3. Cytokinins 4. Ethylene 5. Abscissic Acid. Plant Growth Regulators: Type # 1. Auxins: Auxins (GK Auxein = to grow), isolated initially from human urine were the first plant PGR to be discovered. However, IAA also occurs in human urine, especially [...]