Abstract
【目的】探究膜下滴灌水氮耦合对温室番茄水氮生产函数的影响,寻求影响温室番茄的关键需水阶段,为番茄节水高效生产提供理论依据。【方法】设置4因素3水平水氮耦合正交试验,对温室水氮耦合下番茄的产量进行研究,基于Jensen模型建立了番茄水氮生产函数,并建立其水分敏感指数累积曲线,利用塑料大棚番茄水氮耦合产量结果对水氮生产函数进行验证。【结果】通过模型计算的番茄产量与实测产量的变化趋势一致,模型拟合残差平方和(SSE)为0.010,决定系数R2达到0.793,验证计算值和实测值之间的均方根误差、平均相对误差、平均绝对误差分别为2.98t/hm2、2.53%、2.39t/hm2,各生育期水分敏感指数表现为"开花期(λ2=0.200)>苗期(λ1=0.096)>成熟期( λ3=0.059)",通过水分敏感指数累积曲线计算得到的水分敏感指数与Jensen模型的水分敏感指数具有较好的拟合效果,各因素对番茄产量的影响表现为"开花期灌水>苗期灌水>施氮量>成熟期灌水",开花期灌水量对产量的影响达到显著水平(P<0.05)。T1处理产量最高,达到72.92 t/hm2。番茄的氮肥偏生产力随施氮量的增加而降低。施氮量为250kg/hm2,继续增加氮肥对番茄增产效果不明显,且降低了水分利用效率。试验建立的水氮生产函数具有较高的模拟精度,水分敏感指数累积曲线对水分敏感指数的计算较为准确。在整个生育阶段开花期的水分敏感指数最大。【结论】综合考虑番茄产量及水氮利用效率,设施番茄膜下滴灌水氮优化方案为:苗期采用充分灌水、开花期采用75%充分灌水、成熟期采用75%充分灌水和施氮量250 kg/hm2的组合。
Background: Tomato is an important economic crop planted widely in both north and south of China. In addition to its effect in antioxidant and anti-cancer, tomato is also nutritious and rich in VC, lycopene and other nutrients. Water and nutrients are two abiotic factors determining tomato growth. Irrational irrigation and fertilization, especially when they are used excessively, not only waste resources and contaminate groundwater, but could also compromise crop yield and quality. Understanding how water and nutrients combine to modulate tomato growth is hence critical to its sustainable production.Objective: The overall objective of this paper is to determine the production functions of water and nitrogen of greenhouse tomato in response to water-nitrogen coupling under mulched drip irrigation. We can therefore find its key water-demand stages and provide guidelines for efficient use of water and nitrogen fertilizer in tomato production.Method: The experiment considered four factors and three levels, with all designed using the orthogonal test to study how yield of the tomato responds to change in water and nitrogen coupling. The Jensen model was used to describe the change in tomato yield with water and nitrogen applications.Result:The tomato yield calculated by the model was consistent with the measurements, with the squared sum of the model fitting residuals being 0.01 and the determination coefficient being 0.793. The root mean square error, average relative error and average absolute error between the calculated and the measured yield were 2.98 t/hm2, 2.53% and 2.39 t/hm2, respectively. The water sensitive index at each growth stage was ranked in the descending order as flowering stage (λ2=0.200) > seedling stage (λ1=0.096) > ripening stage (λ3=0.059). The water sensitive index calculated from the cumulative curve of the water sensitive index agreed well with the estimate from the Jensen model. The factors that impacted tomato yield was ranked in the following descending order based on their significance: irrigation at flowering stage>irrigation at seedling stage>nitrogen application>irrigation at maturity stage, with the effect of irrigation at flowering stage being significant (P<0.05). The highest yield was 72.92 t/hm2, achieved by triple irrigations coupled with 350 kg/hm2 of nitrogen application. The partial nitrogen production decreased as nitrogen application increased, and when the nitrogen application exceeded 250 kg/hm2, a further increase in its application did not result in a noticeable yield increase but reduced the water use efficiency. The water-nitrogen production function was accurate and can be used to predict yield of the tomato fertigated by film-mulched drip irrigation. The cumulative curve of the water sensitive index was adequate for calculating water sensitive index, with the water sensitive index at flowering stage being the highest.Conclusion: Considering the yield and water and nitrogen use efficiency, the optimal fertigation under film-mulched drip irrigation was: sufficient irrigation at seedling stage, 75% of the sufficient irrigation at flowering stage and ripening stage respectively, coupled with 250 kg/hm2 of nitrogen application.
Translated title of the contribution | The Effect of Water-nitrogen Coupling on Water-nitrogen Production Functions of Greenhouse Tomato under Mulched Drip Irrigation |
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Original language | Chinese (Simplified) |
Pages (from-to) | 47-54 |
Number of pages | 8 |
Journal | Journal of Irrigation and Drainage |
Volume | 40 |
Issue number | 1 |
DOIs | |
Publication status | Published - Jan 2021 |
Scopus Subject Areas
- Soil Science
- Agronomy and Crop Science
- Water Science and Technology
- Ecology
- Environmental Engineering
User-Defined Keywords
- Tomato
- Water-nitrogen coupling
- Water-nitrogen production function
- Yield