Effect of Polyolefin Film and Light Transition Film on the Growth of Lettuce

In this study, effects of polyolefin(PO) film and light transition film on the growth of lettuce were investigated compared with ethylene-vinylacetate (EVA, antifogging, no drops and longevity type) film covering. Results showed that the temperature and humidity in greenhouse covered with PO film and light transition film were significantly increased. The average temperature in the greenhouse was 4 oC higher than outdoor temperature. The average illumination intensity in the greenhouse covered with PO film was 293.22 umol m-2 s-1, light transmittance was 80.37%, the average illumination intensity in the greenhouse covered with EVA film was 193.04 umol m-2 s-1, light transmittance was 52.91%. Compared with the common film, light transmittance of the PO film was significantly increased. Light transition film increased the chlorophyll content of lettuce by changing the element of the sunlight and increased production of vegetables. PO film and light transition film display a good application prospective in the production of vegetables.