5 . What is the percentage of photosynthetically active radiation (PAR) in the incident solar radiation?
(a) 100%
(b) 50 %
(c) 1-5%
(d) 2-10%
(b) 50%
Since a greater quantity of PAR promotes plant growth through photosynthesis, PAR is necessary for plant growth. The plant receives around half of the visible light or visible rays that the sun emits. Therefore, 50% of the incident solar radiation is photosynthetically active.