Effects of nitrogen and light intensity on tomato (Lycopersicon esculentum Mill) production under soil water control

Abstract

Light, water and nitrogen supply are important factors affecting crops production and growth. To evaluate the effect of different light intensities and nitrogen supply levels with different soil water content on the production of tomatoes, a pot experiment was conducted on the Zijingang campus of Zhejiang University in Hangzhou, China, during the tomato-growing season in 2009. Results showed that the higher the light intensity, the higher the production of fruits under the same nitrogen treatment and the best conditions for optimal yield were: 60% of the traditional nitrogen application, high light intensity and 70-75% soil water content. Under 70 - 75% soil water, nitrate reductase (NR) decreased along with the increased NO3-N supply level, and the contents of soluble sugar and ascorbic acid increased with increased light intensity. This suggested that modulating the relationship between soil water content, light intensity and nitrogen supply level could increase the production and promote fruit quality. Key words: Tomato, light intensity, nitrogen supply, soil water content, biomass.