Effect of Shading on Dry Matter Prodution and Allocation of Greenhouse Tomato

The effects of shading on dry matter production and allocation of greenhouse tomato were studied.Shading was carried out between 11:00~15:00 each day from mid of April when plants had 8～10 leaves to mid of August.Shading material was black nylon with transmission rate of 28%.The results showed that after shading the temperature was remarkable reduced by 6.4℃.Shading not only could delay senescence of tomato plants,but prolong at least about 20 days of biomass quickly accumulating period.Shading had little difference on dry matter allocation to vegetative part and fruit section and had no effect on dry matter content of all organs.