Temperature

• Basic measure of heat measurement
• Enzyme activity doubles or triples with10°C rise in temperature up to optimum level then after that temperature decreases
• At lower temperature the cell freezes and all activity of plant is affected
• As a general rule, greenhouse crops are grown at a day temperature, which are 3 to6°Chigher than the night temperature on cloudy days and 8°C higher on clear days.
• The night temperature of greenhouse crops is generally in the range of 7 to 21°C.
• Primula, grow best at 7°C, carnation and cineraria at 10°C, rose at 16°C,chrysanthemum and poinsettia at 17 to18°C and African violet at 21 to 22°C.