The correct answer is: field capacity.
Field capacity is the amount of water that a soil can hold against gravity. It is the maximum amount of water that a soil can hold after excess water has drained away and the soil has been allowed to drain for a period of time. Field capacity is usually expressed as a percentage of the soil’s dry weight.
Hygroscopic water is the water that is held to the soil particles by molecular forces. It is the water that is present in the soil even when the soil is at its driest point. Hygroscopic water is not available to plants.
Equivalent moisture is the amount of water that would be required to bring a soil to its field capacity if all of the hygroscopic water were removed. Equivalent moisture is usually expressed as a percentage of the soil’s dry weight.
Soil moisture deficiency is the difference between the amount of water that a soil can hold at field capacity and the amount of water that is actually present in the soil. Soil moisture deficiency is usually expressed as a percentage of the soil’s field capacity.
Pellicular water is the water that is held to the soil particles by surface tension. It is the water that is present in the soil in thin films around the soil particles. Pellicular water is available to plants, but it is not as easily absorbed as water that is held in larger pores.