Abstract: Influences of 2 water levels and 3 nitrogen levels reciprocally application on water use efficiency (WUE_Y) and nitrogen use efficiency(NUE) were studied in tomato(cv． Skala) solar greenhouse under similar yield as compared with the conventional method．The results showed that: The increasing effect of three factors on tomato yield was in an order of N ＞ H₂ O．There were interactions between the two factors．WUE_Y was significantly affected by both irrigation and nitrogen amount．Under W1(4 541． 0 m³ /ha)，as the levels of nitrogen amount increased，the WUE_Y also increased， but no significant difference among the WUE_YS．Under W2(2 270． 5 m³ /ha)，N2(373． 77kg /ha) was not significant different from N1．Under the same amount of nitrogen，as the amount of irrigation in- creased，the WUE_Y decreased． N loss percentage was not distinctly affected by water，but strongly affected by the a- mount of nitrogen．Rational water and nitrogen can reduce N loss percentage effectively．

Key words: Water use efficiency, Nitrogen use efficiency, Solar greenhouse, Tomato

CLC Number: 

• S143.1+6

• S641.2