EFFECTS OF NUTRIENT SOLUTION EC, PLANT MICROCLIMATE AND CULTIVARS ON FRUIT QUALITY AND YIELD OF HYDROPONIC TOMATOES (LYCOPERSICON ESCULENTUM)
EFFECTS OF NUTRIENT SOLUTION EC, PLANT MICROCLIMATE AND CULTIVARS ON FRUIT QUALITY AND YIELD OF HYDROPONIC TOMATOES (LYCOPERSICON ESCULENTUM)
复制标题
营养液EC、植物小气候和栽培品种对水培番茄（LYCOPERSICON ESCULENTUM）果实品质和产量的影响
DOI：
10.17660/actahortic.2004.659.70
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发表时间：
2004
期刊：
影响因子：
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通讯作者：
C. Kubota
中科院分区：
文献类型：
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作者：
Min Wu;J. Buck;C. Kubota
在温室（Tucson，AZ）内的两个小气候（东、西）下，在两种营养液电导率（EC）水平（2.6或4.5dSm-1）下，通过在第一个果实桁架形成后添加NaCl和CaCl 2来调节，在岩棉上水培生长4个番茄品种（Blitz，Mariachi，Quest和Rapsodie）。在所有品种中，果实的可溶性固形物（TSS，20 ° C时的%Brix）和番茄红素含量分别增加了12- 23%和34- 85%。温室东侧收获的果实比西侧收获的果实具有更高的TSS，这是由于不同植物小气候因每日PPF（光合光子通量）和VPD（蒸汽压赤字）而变化。然而，番茄红素含量在果实中没有显着的影响，无论是品种或EC的植物小气候。在所研究的品种中，马里亚奇的品种对营养液EC水平的影响最大。7周累积产量在营养液EC和地点之间没有显着差异，无论品种。结果表明，在不减产的前提下，通过调控温室EC和植物小气候，可以生产出高附加值的番茄果实。番茄是世界各地新鲜蔬菜市场上的重要作物。近年来，通过引进更好的栽培方法来提高果实品质引起了种植者的极大兴趣。番茄果实的总可溶性固形物浓度（TSS，测量为%Brix）是决定果实风味和品质的重要变量之一，因为TSS是与果汁中的糖和有机酸浓度直接相关的最常见的指标（Stevens等人，1977; Young等人，1993年）。操纵营养液电导率（EC，dS m-1）是一种众所周知的种植风味增强的番茄的技术，因为营养液中升高的盐度限制了水向果实的运输，从而增加了TSS（亚当斯，1991;米切尔等人，1991;康沃尔语，1992; Lin和Glass，1999）。然而，高EC营养液造成的严重水分胁迫可能导致产量显著降低（亚当斯，1991）。空气环境因子影响果实的生长和品质，并与营养液EC对植株的影响相互作用。据报道，增加光合光子通量（PPF）显著增加番茄植物的叶净光合速率和总碳固定（施瓦茨et al.，2002年）。当PPF低于200 μ mol m-2 s-1时，对植物生长没有影响，直到营养液EC为8 dS m-1;然而，当植物生长在较高的光照强度（1000 μ mol m-2 s-1）时，番茄植物生长被相同的EC处理降低（Xu et al.，1995年）。
Four cultivars (Blitz, Mariachi, Quest and Rapsodie) of tomato were grown hydroponically on rockwool in two microclimates (east and west) inside the greenhouse (Tucson, AZ) under two nutrient solution electrical conductivity (EC) levels (2.6 or 4.5 dS m -1 ), adjusted by adding NaCl and CaCl2 after the setting of first fruit truss. In all cultivars, total soluble solid (TSS, %Brix at 20 o C) and lycopene concentration of fruits increased by 12-23 % and 34-85 %, respectively, with increasing EC level. Fruits harvested from the east side of the greenhouse had higher TSS than those from the west side, due to the different plant microclimate varying by daily PPF (photosynthetic photon flux) and VPD (vapor pressure deficit). However, lycopene concentration in fruits was not significantly affected by plant microclimate regardless of cultivars or EC. The cultivar of Mariachi showed the strongest effect in response to nutrient solution EC levels regarding both TSS and lycopene concentration among the cultivars examined. The cumulative yield at 7 weeks showed no significant differences between nutrient solution EC and locations, regardless of cultivars. The results indicated that value added tomato fruits could be produced by manipulating EC and plant microclimate in the greenhouse without causing yield reduction. INTRODUCTION Tomato is an important crop in fresh vegetable market around the world. Recently, there is great interest for growers to improve the fruit quality by introducing better cultivation methods. Total soluble solid concentration (TSS, measured as %Brix) of tomato fruits is one of the important variables that determines the fruit flavor and quality because TSS is the most common index associated directly with sugars and organic acids concentrations in the juice (Stevens et al., 1977; Young et al., 1993). Manipulation of nutrient solution electrical conductivity (EC, dS m -1 ) is a well known technique to grow flavor-enhanced tomato because the elevated salinity in nutrient solution restricts the water transport to fruits and thus increase the TSS (Adams, 1991; Mitchell et al., 1991; Cornish, 1992; Lin and Glass, 1999). However, too severe water stress from high EC nutrient solution may cause a significant yield reduction (Adams, 1991). The aerial environmental factors influence fruit growth and quality, and they also interact with the nutrient solution EC effects on the plant. It was reported that increasing photosynthetic photon flux (PPF) significantly increased the leaf net photosynthetic rate and total carbon fixed by tomato plants (Schwarz et al., 2002). When the PPF was lower than 200 mol m -2 s -1 , there was no effect on plant growth up to a nutrient solution EC of 8 dS m -1 ; however, when the plants were grown at a higher light intensity (1000 mol m -2 s -1 ), the tomato plant growth was reduced by the same EC treatments (Xu et al., 1995).