A greenhouse of semi-circular shape was employed to study the effect of spe
ctral light response on the stem-cutting propagation of horticultural plant
s. The number of days taken for the root formation were noted and it was ob
served that the stem cuttings showed earlier root formation under a red-tin
ged greenhouse followed by a blue-tinged greenhouse. The UV-stabilised shee
t prolonged the formation of well-formed roots by an additional three days
over that for the control system. The study shows that the temperature grad
ient is not only a minimum at canopy level but also negative throughout in
blue cladded greenhouse and a maximum vertical heat flux of zero is noticed
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