Effects of Different Colored Light-quality Selective Plastic Films on Growth, Photosynthetic Abilities, and Fruit Qualities of Strawberry

Light quality regulates plant growth and photosynthesis, the drivers of fruit quality, and light quality can be controlled by colored light-quality selective plastic films in field production. To identify the optimal color of plastic film for high-quality strawberry (Fragaria x ananassa) fruit production, plant growth, photosynthetic abilities, and fruit qualities were investigated under transparent (T), red (R), yellow (Y), green (G), blue (B), and purple (P) films The R film showed the maximum promoting effects on leaf area, petiole length, leaf biomass, and shoot biomass. The R film improved photosynthetic abilities by increasing photosynthetic pigment content, quantum yield (phi Po), electron transfer (Psi o and phi Eo), the density of reaction centers (RC/CSm), and the photosynthetic performance index (Plabs), and by decreasing the dissipation of absorbed solar energy as heat (phi Do), while varied reverse effects were detected under other films For fruit qualities, the R film also improved fruit weight and the content of total sugar, anthocyanin, and soluble protein. Therefore, the R light-quality selective plastic film should be suitable for strawberry production due to the promoting effects on plant growth, photosynthetic abilities, and fruit weight and quality.