How does soya beans and broccoli manage to cope under drought stress?

Answer 1

Soya beans and broccoli have developed certain mechanisms to cope with drought stress, which help them survive and continue their growth even in unfavorable conditions. Here are some ways in which they manage to cope under drought stress:

1. Drought escape: Soya beans and broccoli have a relatively short life cycle, so they can complete their entire growth and reproductive cycle before the onset of severe water scarcity. This allows them to produce seeds or crops before the drought stress becomes too severe.

2. Root adaptations: Both soya beans and broccoli can develop deeper and extensive root systems to maximize water uptake. Deeper roots help them access water from lower soil layers where moisture is more abundant.

3. Drought avoidance: These plants have the ability to regulate their stomata, which are tiny openings on the surfaces of leaves. By partially closing their stomata during drought stress, they reduce the water loss through evapotranspiration. This helps in conserving water and preventing excessive drying out.

4. Leaf adaptations: Soya beans and broccoli often undergo leaf rolling or curling during drought conditions. This reduces the leaf surface area exposed to direct sunlight, which in turn decreases water loss through transpiration.

5. Osmoregulation: Both plants can accumulate compatible solutes such as proline and sugars within their cells. These solutes help maintain cell turgor pressure during water scarcity and prevent cellular dehydration.

6. Antioxidant defense: Soya beans and broccoli produce antioxidants that can help scavenge harmful reactive oxygen species (ROS) produced during drought stress. This helps protect their cellular structures from oxidative damage.

7. Hormonal regulation: Drought stress triggers the production of specific hormones, such as abscisic acid (ABA), which help regulate plant responses under water scarcity. ABA promotes stomatal closure, reduces shoot growth, and enhances root growth to cope with drought stress.

Overall, through a combination of physiological, morphological, and biochemical adaptations, soya beans and broccoli have evolved mechanisms to withstand and survive drought stress to some extent. However, their productivity may still decline under severe and prolonged drought conditions.