How do the effects of auxins, ethene, and gibberellins benefit agricultural and horticultural practices?

SouravNovember 12, 2024

Answer

The effects of auxins, ethylene, and gibberellins significantly benefit agricultural and horticultural practices by enhancing plant growth, improving yield, and managing fruit ripening. Here’s a detailed overview of how each hormone contributes to these benefits:

1. Auxins

Auxins are crucial for regulating various growth processes in plants. Their applications in agriculture and horticulture include:

• Promoting Cell Elongation: Auxins stimulate the elongation of cells, particularly in stems and shoots. This property is utilized to promote overall plant growth and increase crop yields by enhancing height and vigor.
• Root Development: Auxins are commonly used in rooting powders to encourage root formation in cuttings, facilitating vegetative propagation. This leads to faster and more successful rooting of plants.
• Apical Dominance: Auxins produced at the apical bud inhibit the growth of lateral buds, ensuring that the main shoot grows more vigorously. This is useful for shaping plants and maximizing light capture.
• Fruit Development: Auxins are involved in parthenocarpy, which allows for the development of seedless fruits without pollination. They also help prevent premature fruit drop in crops like apples and pears.
• Weed Control: Synthetic auxins, such as 2,4-D, are used as herbicides to selectively kill broadleaf weeds while protecting cereal crops like wheat and corn.

2. Ethylene

Ethylene is a gaseous hormone that plays a vital role in fruit ripening and other growth processes:

• Fruit Ripening: Ethylene triggers the ripening process in many fruits by promoting changes such as softening, color change, and flavor development. This is essential for ensuring that fruits reach consumers at optimal ripeness.
• Controlled Ripening: In the food industry, ethylene is used to manage the timing of ripening during storage and transport. For example, applying ethylene or ethylene-releasing compounds can synchronize ripening in harvested fruits.
• Flowering Promotion: Ethylene can stimulate flowering in certain plants, enhancing productivity and yield.
• Abscission Control: Ethylene regulates the shedding of leaves and fruits (abscission), which can be manipulated to improve harvest efficiency.

3. Gibberellins

Gibberellins are essential for various aspects of plant growth and development:

• Breaking Seed Dormancy: Gibberellins play a key role in breaking dormancy in seeds, promoting germination by activating enzymes that degrade stored food reserves. This leads to uniform crop emergence.
• Increasing Fruit Size: Gibberellins are used to enhance fruit size by promoting cell division and elongation. They are particularly effective in grapes and tomatoes, where they can also induce parthenocarpy (seedless fruits).
• Promoting Flowering: Gibberellins facilitate flowering in many long-day plants, allowing for better control over flowering times and improved yields.
• Stem Elongation: Gibberellins promote stem elongation by stimulating cell division and loosening cell walls, which can be beneficial for crops that require taller growth forms.
• Delayed Senescence: Gibberellins can delay maturity and senescence in certain fruits, allowing for extended storage times and improved marketability.