Baker & Baker's Indole-3-acetic acid (IAA) is a crucial plant hormone with various applications in agriculture. It plays a vital role in regulating plant growth, development, and responses to environmental stimuli. Here's a description of its uses in agriculture:

1. Root Development: IAA promotes root growth and development in plants. It helps in the formation of new roots and lateral root branching, leading to better nutrient uptake and water absorption. This is particularly important during the early stages of plant growth and establishment.

2. Cell Elongation and Differentiation: IAA regulates cell elongation and differentiation, influencing the overall growth and development of plants. It promotes elongation of cells in stems and leaves, contributing to the growth of plant tissues and structures.

3. Tissue Culture: IAA is widely used in tissue culture techniques for the propagation of plants. It stimulates the growth of callus and induces the formation of roots and shoots from explants, facilitating the mass production of plants in a controlled environment.

4. Fruit Development: IAA plays a role in fruit development and ripening. It helps in the formation and enlargement of fruit tissues, seed development, and fruit ripening processes. Proper application of IAA can improve fruit size, quality, and yield.

5. Apical Dominance: IAA regulates apical dominance in plants, controlling the growth of the main shoot and the inhibition of lateral bud growth. By modulating the levels of IAA, growers can manipulate plant architecture and branching patterns to optimize yield and shape.

6. Seed Germination: IAA is involved in the regulation of seed germination processes. It promotes the breakdown of dormancy and stimulates the initiation of germination, ensuring uniform and timely seedling emergence in crops.

7. Stress Response: IAA helps plants cope with various environmental stresses such as drought, salinity, and temperature extremes. It regulates stress-responsive genes and pathways, enhancing the plant's ability to withstand adverse conditions and maintain productivity.

Overall, indole-3-acetic acid is a versatile hormone with wide-ranging effects on plant growth, development, and responses to environmental cues. Its applications in agriculture contribute significantly to improving crop productivity, quality, and resilience in diverse farming systems.