The present investigation was carried out at College of Horticulture, Anantharajupeta during 2018-19. The experiment was laid out in Randomized Block Design, with three replications and with 8 genotypes. The treated rhizomes were planted under 50 per cent shadehouse condition. All the physiological attributes and anthocyanin content varied significantly among multiple heliconia genotypes studied under shadehouse conditions. Among different genotypes tried, leaf area ( cm2 ), SPAD (SCMR) value for chlorophyll content (), stomatal conductance ( mol m-2 s -1 ), rate of photosynthesis ( µmol m-2 s -1 ), transpiration rate ( mmol m-2 s -1 ) and anthocyanin content in flowers ( mg 100 g-1 tissue) recorded were highest in genotype G6. Significantly more leaf intercellular CO2 ( µmol m-2 s -1 ) and leaf temperature ( 0C), respectively was recorded in genotype G3. While the genotype G5 had maximum number of stomata ( mm2 ). | Multiple heliconia genotypes under 50 per cent shadehouse conditions: Physiological and biochemical responses