滴灌施肥水肥耦合对温室番茄产量、品质和水氮利用的影响

【关键词】:番茄;;滴灌施肥;;产量;;品质;;水氮利用;;硝态氮
【摘要】:【目的】水肥是限制作物增产的两大因子,不合理的灌溉与施氮不仅难于增加产量,还会增加土壤剖面硝态氮累积、降低作物品质及水氮利用效率。针对西北半干旱地区温室蔬菜灌水和施肥存在的问题,通过滴灌施肥水肥耦合对温室番茄产量品质和水氮利用的影响,研究滴灌施肥条件下温室番茄高产优质高效的灌水施肥制度。【方法】通过温室番茄小区试验,设常规沟灌施肥(100%ET0,N240-P2O5120-K2O150 kg·hm-2)以及3个滴灌水量(高水W1:100%ET0、中水W2:75%ET0、低水W3:50%ET0)和3个施肥水平(高肥F1:N240-P2O5120-K2O150 kg·hm-2、中肥F2:N180-P2O590-K2O112.5 kg·hm-2、低肥F3:N120-P2O560-K2O75 kg·hm-2),共10个处理,分析番茄生长产量、品质、土壤硝态氮分布以及水氮吸收利用对不同灌水量和施肥量的响应规律。【结果】与常规沟灌施肥相比,滴灌施肥增加番茄产量31.04 t·hm-2、干物质量3 208 kg·hm-2和总氮吸收量73.13 kg·hm-2,增幅分别为46.9%、54.0%和82.4%,同时增加果实中维生素C(Vc)含量61.8%;降低土壤中硝态氮含量;水分利用效率(WUE)和氮肥利用率(NUE)分别增加46.4%和76.5%。滴灌施肥条件下,W1F2处理总干物质量最大(9 248 kg·hm-2),产量和植株氮素吸收量均与灌水量和施肥量正相关,增加施肥量带来的增产效应大于灌水,且W1F2处理产量和氮素吸收量增加幅度最大。增加灌水量,降低施肥量,WUE逐渐下降,NUE逐渐上升,W3F1处理WUE最大(47.7 kg·m-3),W1F3处理NUE最大(65.6%),且W3F2处理的WUE和W1F2处理的NUE增加幅度明显大于其他处理。土壤中硝态氮含量受灌水、施肥以及水肥交互效应影响显著,随灌水量的增加呈先增大后降低的趋势,随施肥量的增加逐渐增大,在滴头正下方没有明显累积,在湿润土体的横向边缘产生累积,W1F2处理土壤中硝态氮含量较小,分布更均匀。增大灌水量显著降低番茄Vc、番茄红素和可溶性糖含量以及营养累积量;增大施肥量,品质含量以及营养累积量呈先增大后降低的趋势;W3F2处理获得最大的Vc和番茄红素含量及营养累积量,最大的可溶性糖含量及较大的营养累积量。【结论】温室番茄滴灌施肥技术能够达到高产优质和高效的目的,当追求产量和氮肥利用率时,高水中肥(W1F2:100%ET0,N180-P2O590-K2O112.5 kg·hm-2)处理能获得较高的产量和NUE以及较低的土壤硝态氮含量;当追求品质和水分利用效率时,低水中肥(W3F2:50%ET0,N180-P2O590-K2O112.5 kg·hm-2)处理获得最大的维生素C、可溶性糖和番茄红素含量以及较高的水分利用效率。
【Objective】Water and fertilizer are two major factors for limiting crop yield increase.Unreasonable application of irrigation and nitrogen can hinder yield increase,but increase the soil nitrate accumulation,and reduce the crop quality,water and nitrogen use efficiency.The study was aiming at dealing with the problems of irrigation and fertilization on greenhouse vegetables in semi-arid northwest areas,which through the effects of irrigation and fertilizer coupling on greenhouse tomato yields,quality,and water and nitrogen use efficiency under fertigation.The purpose of this study was to research a high-yield,good-quality and high-efficiency fertigation system for drip-irrigated greenhouse tomato.【Method】Greenhouse tomato plot experiments were conducted to analyze the responsive rules of irrigation amount and fertilizer rate on tomato growth,yield,quality,distribution of soil NO3--N,water and nitrogen absorption and utilization.The experiments consisted of a furrow fertigation treatment(control treatment,100% ET0,N240-P2O5120-K2O150 kg·hm-2),three drip irrigation levels(high irrigation,W1,100% ET0; medium irrigation,W2,75% ET0; low irrigation,W3,50% ET0) and three fertilizer levels(high fertilizer,F1,N240-P2O5120-K2O150 kg·hm-2; medium fertilizer,F2,N180-P2O590-K2O112.5 kg·hm-2; low fertilizer,F3,N120-P2O560-K2O75 kg·hm-2),and total of 10 treatments.【Result】The results showed that tomato yield,dry matter accumulation and total nitrogen absorption in drip fertigation treatments were 31.04 t·hm-2,3 208 kg·hm-2 and 73.13 kg·hm-2 higher than that in the furrow fertigation treatment,increased by 46.9%,54.0% and 82.4%,respectively.In addition,the fruit Vc content,water use efficiency(WUE) and nitrogen use efficiency(NUE) increased by 61.8%,46.4% and 76.5%,respectively,but the NO3--N content in the soil decreased.In drip fertigation treatments,the highest total dry matter accumulation of W1F2 treatment was 9 248 kg·hm-2,both yield and plant nitrogen uptake were positively related to the amount of irrigation and fertilizer.The fertilization was found to exert more impact on the yield compared with irrigation.The treatment W1F2 had the largest range of yield increase and nitrogen uptake.The WUE decreased and the NUE raised gradually with the increase of irrigation amount and decrease of fertilizer rate.The treatment W3F1 produced the largest WUE(47.7 kg·m-3) and the W1F3 treatment of the largest NUE(65.6 %),respectively.The WUE of W3F2 and the NUE of W1F2 had much more greater increasing scale than the other treatments.The nitrate nitrogen content in soil was significantly affected by irrigation,fertigation and irrigation-fertigation interactive effects.Nitrate nitrogen content in the soil increased first but then decreased with the increase of irrigation water.Nitrate nitrogen content consistently increased as the increase of fertilizer.Significant nitrate nitrogen accumulation was identified at the lateral boundary of the wetted volume rather than under the dripper.The treatment W1F2 with high irrigation water and medium fertilizer produced lower nitrate nitrogen content and more uniform distribution of nitrate nitrogen in the soil than other treatments.Increases in irrigation water significantly reduced fruit Vc,lycopene and soluble sugar contents and their nutrition accumulation,but the quality indicators' content and nutrition accumulation were increased first then decreased with the increase of fertilizer.The treatment W3F2 had the largest Vc and lycopene content as well as nutrition accumulation,and the largest soluble sugar contents as well as larger nutrition accumulation.【Conclusion】The results indicated that the drip fertigation technology could achieve the goal of high yield,good quality and high efficiency for greenhouse tomatoes.The treatment W1F2 with high water and medium fertilizer(100%ET0,N180-P2O590-K2O112.5 kg·hm-2) was preferable for higher yield and NUE interest,as well as lower nitrate nitrogen content in soil; but the treatment W3F2 with low water and medium fertilizer(50%ET0,N180-P2O590-K2O112.5 kg·hm-2) was more appropriate in terms of higher WUE and the largest Vc,lycopene and soluble sugar contents.