A model to determine quantitative effects of light and temperature on organic tomato seedlings

The present study was conducted to determine the quantitative effects of light and temperature on growth and development of organic tomato (Solanum lycopersicum L.) seedlings in a glasshouse under ecological conditions of Samsun Province of Turkey. Seedlings were grown in four different periods (seeds sown on 29 September for 1st period; 2 December for 2nd period; 18 March for 3rd period and 6 July for 4th period). In order to create different light intensities, shading material having a shading capacity of 50% in 1, 2 and 3 layers was used in each period after seeding. The effects of light and temperature on plant growth and development (leaf area, stomatal conductivity, leaf chlorophyll content, plant height, stem diameter and total plant vegetative dry weight) and the number of days from sowing to plantation of seedlings, were investigated. Obtained results revealed decreasing number of days from sowing to seedling plantation with increasing light intensities. Finally, the number of days from sowing to seedling plantation to be used in organic tomato seedling production was modeled based on the variations in temperature and light intensity (r2 = 0.92).