Abstract: To understand the regulation of crop dry matter production and allocation, and to improve crop dry matter production and water, nitrogen use efficiency by applying the reasonable amount of nitrogen fertilizer and water irrigation, the pot experiment of nitrogen and water coupling was conducted and tomato cultivar Hongzungui was selected as the material. The 4 leaves seedlings were planted in the nutrition bowls(Model 30 cm×28 cm, with moss peat as media) for 6 treatments(2 nitrogen level and 3 irrigation level), each with 40 pots and replicated 4 times for total of 960 plants. The experiment was from Apr.17 to Aug.3, 2017 for 109 days. Plants samples were taken every 10 days to measuring the growth status. The results showed, compared with the treatment of low nitrogen(N1), it was increased by 21.15%, 26.57% and 35.54% of growth rate, plant total dry matter and fruit dry matter under high nitrogen level(N2), respectively, and the proportion of fruit dry matter within plant dry matter was increased by 4%. Under the N1 level, more dry matter was distributed to the root section. Compared with N1, the proportion of increased dry matter allocated to the fruit in N2 was increased by about 8.24% with each 1 g increased of cumulative nitrogen application. The more irrigation, the better for plants grew in this experiment. Compared with low water level(W1), the total dry matter was increased by 23.55% and 13.29%, fruit dry matter by 19.75% and 16.28% in high and medium water irrigation level(W3, W2), respectively. There were about 66%-70% of increased plant dry matter production allocated to the fruit with additional 1 L irrigation amount. Plant achieved the highest dry matter accumulation under the treatment N2W3. Compared with N1W1, the total dry matter of per plant and the dry matter of fruit per plant were increased by 57.24% and 61.58% with N2W3. Under the same nitrogen level, the higher the irrigation water, the higher the nitrogen use efficiency was, especially at high nitrogen level. Nitrogen use efficiency in N2W3 increased by 28.58% compared with that of N2W1. Under the same water level, the higher nitrogen application, the higher the water use efficiency was, especially under high water treatment. The water use efficiency of N2W3 was increased by 33.97% compared with that of N1W3. It was concluded that once the irrigation water was increased at high nitrogen level, or the nitrogen level was increased at high water irrigation, the production rate, the total plant dry matter and the fruit dry matter were increased. The interaction of water irrigation and nitrogen application were promoted each other, and the treatment of N2W3 was suggested the best choice in this research range.

Key words: Tomato, Dry matter production, Water and nitrogen coupling, Nitrogen use efficiency, Water use efficiency

CLC Number: 

• S626.5