(a) Cloudy days
(b) No rainfall in the area
(c) Good manuring in the area
(d) Stomata get blocked due to dust
- Due to the lack of sunlight, the rate of photosynthesis will slow down.
- Rainfall has no effect on photosynthesis rates.
- Manuring has no effect on photosynthesis rates.
- Stomata obstruction reduces the rate of photosynthesis because it reduces the availability of pf. Carbon-di-oxide.