HORTICULTURE

Detailed explanation-1: -As the relative humidity of the air surrounding the plant rises the transpiration rate decreases. It is easier for water to evaporate into dryer air than into more saturated air. Increased movement of the air around a plant will result in a higher transpiration rate.

Detailed explanation-2: -At high atmospheric humidity, transpiration is low. This is because the rate of transpiration is directly proportional to the saturation deficit. It is dependent on the gradient of vapor pressure. Thus, the higher the humidity, the lower the rate of transpiration.

Detailed explanation-3: -When the relative humidity is high, the atmosphere contains more moisture. This lowers the driving force for transpiration. Lower relative humidity levels correspond to less moisture in the atmosphere and thus a higher driving factor for transpiration.

Detailed explanation-4: -Increased humidity has a reduces transpiration. The lower the humidity the easier it is for the plant to release water.

Detailed explanation-5: -Transpiration is reduced if the air outside is humid. High humidity in the air reduces the rate of outward diffusion of the internal water vapour across stomata, thereby reducing the rate of transpiration.