Impact of solar irradiance on gas exchange and growth of heliconia grown in a semi-arid region

ABSTRACT Light is essential for providing energy photosynthetic reactions and has a complex not yet fully understood effect on heliconia growth yield. Thus, the objective of this study was to evaluate light intensity photosynthesis under semi-arid conditions screen potential genotypes tolerant high solar irradiation levels during vegetative stage. The experiment conducted in Petrolina, PE, Brazil, whose geographic coordinates are 09° 19’ 14” S, 40° 32’ 40” W, with an average altitude 387 m. experimental design used randomized blocks, arranged split-plot scheme, treatments were composed two intensities (full sun 50% shading) five (Heliconia psittacorum x H. spathocircinata cv. Golden Torch; Red Opal; bihai Lobster Claw Two; rauliniana rostrata). Growth gas exchange assessments 100th day after trial initiation. did influence rates (A), stomatal conductance (gs), or transpiration (E) plants. However, isolated genotype revealed that plants Opal, bihai, rauliniana, Torch had higher values A, gs, E. Overall, shading improved plant growth. We conclude exhibited greatest tolerances irradiance conditions.