Effects Of Fertigation On Yield, Water And Nitrogen Use Efficiency Of Tomato Under Chinese Greenhouse Condition

In China, it became more seriously in water resource waste, environment pollution and the declineof the quality of vegetables. By using block experiment and indoor analysis, the experiment was to studythe tomato yield, quality and water-fertilizer use efficiency among the different fertigation methods. Thepurpose was to provide certain theoretical basis for high quality vegetable and the integratedmanagement of water﹠nitrogen.The study was conducted in the greenhouses at 'Jinliuhuan' agricultural garden, Changping district,Beijing. During the autumn-winter season (2010.8-2011.1), the study conducted four treatments(included two fertigation methods and two lower irrigation limits) which were D80%, D60%, G80%, andG60%. During the winter-spring season(2011.2-7), we conducted the two different frequencies using dripand furrow irrigation methods, which included drip irrigation weekly treatment (D7), drip irrigationbiweekly treatment (D14), conventional furrow irrigation weekly treatment (G7) and conventional furrowirrigation biweekly treatment (G14).The two season experiments were to compare the drip irrigation andfurrow irrigation from aspects of the tomato yield, quality, water﹠nitrogen use efficiency, and to studythe response mechanism of dry matter accumulation of tomato, photosynthetic characteristics ofphysiological characteristics. The main conclusions are as follows:1. Compared with furrow fertigation technology, the drip fertigation treatments could significantlyimprove the tomato yield. The tomato yields of drip fertigation methods with lower irrigation limits of60%FC and80%FC could increase26.3%and31.2%compared with the same lower irrigation limit.And the drip fertigation frequency of7d and14d could increase yield15%and23.1%compared with thesame frequency furrow method. Using the same irrigation method, the tomato yield of drip fertigationmethod with lower irrigation limit of80%FC was higher than60%FC treatment, and the drip fertigationwith irrigation frequency of7d had also higher tomato yield than14d fertigation treatment, but the yieldswere no significant difference. The results showed that different fertigation methods had significantdifference on tomato yield, the drip fertigation technology had significant advantages in yield and theoptimal irrigation parameters could give full play to improve yield.2. The results of water use efficiency among the two experiments showed that the drip fertigationwere significantly higher than the furrow fertigation, which were the results of superposition of dripirrigation water use efficiency and yield. The drip fertigation treatments could not only reduce thetomato water consumption, but also improve the tomato yield because of the accurately supply to meetthe water-fertilizer needs of crops, which caused high water use efficiency. The high frequency dripfertigation treatment reduced tomato water consumption, improved water use efficiency and tomato yieldcompared to the low frequency drip fertigation treatment. And the furrow fertigation treatments had nosignificant difference in yield, water consumption and water use efficiency.3. The results of nitrogen use efficiency with drip fertigation were significantly higher than thefurrow fertigation. And the results in crop uptake of nitrogen among the different organs were fruits>leaf>stem and the content of nitrogen in fruits were significant higher than other organs. Thecontents of N uptake in fruits among the drip fertigation treatments were higher than the furrowtreatments, which showed that the drip fertigation could improve the ability of N uptake and nutrientsresulting in economic yield. While the nitrogen utility efficiency in furrow fertigation under the sandyland was obviously reduced. The results showed that the furrow fertigation should not be used for thesandy soil because of the furrow fertigation intensity and easy to produce deep infiltration resulting inthe lower utilization of N.4. The distributions of soil volumetric water and NO3ˉamong the different irrigation methods wereobvious difference. At the root zone, the soil water content of drip irrigation was higher than the furrowirrigation treatment and the result of furrow irrigation was higher than drip irrigation at the deeper soillayer. The differences in soil water distribution were mainly determined by the technical characteristics.The results showed that the content of0-60cm NO3ˉin the drip treatments was higher than the furrowtreatments and the content of60-90cm NO3ˉin the drip treatments was significantly lower than thefurrow irrigation.5. Compared with the furrow treatments, the drip irrigation treatment could significantly improvethe tomato plant height, stem diameter, leaf area index, fruit diameter and above-ground dry matter. Theroot length and root dry biomass in the drip fertigation treatments were lower than in the furrowtreatments, but the root activity was significantly higher than the furrow irrigation treatments. The driptreatments had the high daily maximum Pn and Tr values than the furrow irrigation. During the wholegrowth period, the average rate of photosynthesis and transpiration rate of drip irrigation treatment werehigher than that of furrow irrigation treatment. The yield component showed that the number of fruits perplant had no difference among the treatments, but the fruit weight of drip irrigation treatments wassignificant higher than furrow treatments. The comprehensive analysis of these results could be inferredthat compared with the furrow treatments, the drip fertigation treatments could accurately apply thewater and fertilizer and meet the needs. The roots were mainly in the surface and the root activity topromote nutrition absorption of water and N resulting in increasing the aboveground biomass.Meanwhile, the excellent water and fertilizer supplied conditions made the net photosynthetic rate andtranspiration rate high level and promoted the conversion of nutrient,dry matter accumulation, fruitquality and ultimately lead to increase the yield.6. There was no significance difference of greenhouse temperature in different irrigation andfertilization treatments, while existed remarkable difference (9.1%-10.2%) of the greenhouse air relativehumidity between autumn-winter and winter-spring experiments.