Available water for plant indicates water held in

Correct option is A

The correct answer is (A) 0.33 – 15 bar

Explanation:
• Not all water in the soil is available to plants. Available Water Capacity (AWC) is the range of soil moisture that plants can actually extract.
• The upper limit is Field Capacity (FC), which is the amount of water held in the soil after excess water has drained away due to gravity. This occurs at a tension of $0.33 bar$ (or $1/3 atm$).
• The lower limit is the Permanent Wilting Point (PWP), where the soil holds water so tightly that plant roots cannot exert enough suction to pull it out. This occurs at $15 bar$ tension.
• Therefore, water held between $0.33$ and $15 bar$ is considered the available water.

Information Booster:
• In sandy soils, Field Capacity is often reached at lower tensions, around $0.1 bar$.
• Hygroscopic water is held at tensions above $31 bar$ and is completely unavailable.
• Gravitational water is held at tensions below $0.33 bar$ and drains out too quickly for plants to use.

Additional Knowledge:
• Above 15 bar (Option C): This is called unavailable water (hygroscopic and some capillary water).
• Below 0.1 bar (Option D): This is mostly gravitational water found in large macropores immediately after rain or irrigation.