Which one of the following will not directly affect transpiration?
1.  Temperature

2.  Light

3.  Wind speed

4.  Chlorophyll content of leaves

(d) Chlorophyll content will not affect the rate of transpiration.
Options (a), (b) and (c) all affect the rate of transpiration.
(a) Temperature increases the rate of transpiration.
(b) Light quality and intensity also affect the rate of this phenomenon.
(c) Wind speed higher the wind speed, more will be the rate of transpiration.
Page 187, XI NCERT