The Effect of Low Light Intensity by Dust of Greenhouses on Tomato Productivity

The light of the sun have influence on the plant growth and pest occurrence and also the productivity and quality of greenhouse crops is reduced according to the light condition in the greenhouse. The light saturation point of tomato is 70,000 lux and the production of tomatoes is directly related to solar radiation. In Korea, most tomato crop is produced in a greenhouse. In recently, shading damage on tomato cultivated main producing areas is increasing due to the civil engineering and construction dust. In this study, the dust of the construction site was performed to determine the impact of the growth and productivity of tomatoes cultivated greenhouse. The clay powder 0g/‡u, 15g/‡u, 25g/‡u diluted in water was attached to the cladding according to the shading rate of 0%, 30%, 45%. The cultivating of tomato was performed in two layer vinyl greenhouse, in order to prevent loss of dust by rain or wind. Tomato was planted in September and harvested from November. As a results, the dry weight of tomatoes decreased 15%, 23 % compared with non-treated due to the 30%, 40% reduction of sunlight and sugar content 0.4 to 0.6 °Brix low results are shown. The calculated reduction in the harvest of tomatoes due to the shading rate equation is Y = 0.9248x – 0.5857. As this appears to mean the lack of sunlight in winter, a technology is needed sunshine damage due to dust, such as development of a film not attached to dust and  supplementary lighting technology.