Soil Temperature

Soil temperature is known to influence water absorption and ultimately transpiration to a considerable extent. In many plants water absorption is reduced sharply below 10°C. Water absorption also slows down above 25°C. In most instances, temperatures above 40°C in the rhizosphere do not support water absorption and plant may show signs of wilting. The following are the reasons suggested for the reduced absorption of water at low temperature:

• Decreased root growth,
• Increased viscosity of water,
• Increased resistance of water into roots due to decreased permeability (increased hydraulic resistance) of cell membranes and
• Decreased metabolic activity of root cells.