1 College of Water Resources and Architectural Engineering， Northwest A & F University， Yangling 712100， Shaanxi，
China； 2College of Resources and Environment， Northwest A & F University， Yangling 712100， Shaanxi， China
Abstract：This study is to find out the effects of irrigation amount and fertilizer applying quantity
of nitrogen，phosphorus and potassium on tomato（ Lycopersicon esculentum Mill.）lycopene content
under alternate subarea root-zone irrigation. Regression model on water and fertilizer factors and tomato
lycopene content was established with quadratic orthogonal regressive rotation design with 4 factors by
pot experiment. The results showed that if other factors were zero codes，lycopene content in tomato
decreased linearly with the increase of irrigation amount，while increased with the increase of nitrogen
and phosphorus fertilizers applying quantity，but it would not change along with the change of potassium
fertilizer applying quantity. The interaction between irrigation amount and potassium，nitrogen and
phosphorus fertilizer applying quantity presented negative effect on the accumulation of tomato lycopene
content. Under the condition of alternate subarea root-zone irrigation, over irrigation was not favorable for
the increase of lycopene content in tomato. Rational increase of nitrogen，phosphorus fertilizers applying quantity could effectively increase lycopene content in tomato.
