Reduction of Nitrate Content in Baby-Leaf Lettuce and Cichorium endivia Through the Soilless Cultivation System, Electrical Conductivity and Management of Nutrient Solution.
Reduction of Nitrate Content in Baby-Leaf Lettuce and Cichorium endivia Through the Soilless Cultivation System, Electrical Conductivity and Management of Nutrient Solution.
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DOI：
10.3389/fpls.2021.645671
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发表时间：
2021
影响因子：
5.6
通讯作者：
Elia A
中科院分区：
文献类型：
--
作者：
Conversa G;Bonasia A;Lazzizera C;La Rotonda P;Elia A
无土栽培系统是通过管理营养液（NS）盐度和氮有效性来控制硝酸盐的有效工具，然而，这些硝酸盐降低策略需要根据物种/基因型特异性反应与气候和生长条件相互作用进行适当校准。在秋早春（莴苣）和冬春（莴苣）条件下，在两种NS盐度（EC = 2.5和3.5 dS m−1）（EC2.5和EC3.5）水平下，以落流（EF）和漂浮（FL）体系生长的莴苣和菊苣为试验材料，进行了3项试验。在秋季和冬季循环中，在EC2.5条件下测试了氮剥夺（收获前几天取氮）。ef系统导致根主要生长的基质中盐度增加，因此它模仿了EC3.5处理的效果。在冬生生菜中，EF系统或EC3.5处理均能有效降低硝酸盐水平，但不影响产量，EF幼叶的品质（颜色、干物质、叶绿素、类胡萝卜素、维生素C、酚）均有改善。在这两个季节，EF/EC3.5处理导致产量下降，尽管硝酸盐含量进一步降低，产品质量有所提高。这种反应与EC3.5/EF所施加的盐胁迫的增加密切相关，这一点在同时积累Cl−方面得到了突出体现。在早春，FL/EC3.5组合可能代表了产量、硝酸盐含量和产品质量之间的权衡。相比之下，在冬栽菊苣中，EC3.5、EF和EC3.5/EF降低了硝酸盐水平，但对产量、产品质量和Cl -吸收没有影响，因此证明它们比生菜更耐盐。晚春周期的高温促进了硝酸盐和Cl−的吸收，克服了EF系统或EC3.5充电盐对硝酸盐的控制作用。停药3 d（生菜）或6 d（卷叶菜）后硝酸盐水平下降。在紫叶莴苣和ef种植的莴苣中，它引起产量下降，但同时改善了嫩叶外观和营养品质。考虑到所使用的无土系统和物种特有的特征，需要更多的见解来微调NS移除的持续时间。
Soilless cultivation systems are efficient tools to control nitrates by managing nutrient solution (NS) salinity and nitrogen availability, however, these nitrate-lowering strategies require appropriate calibration based on species/genotype-specific responses interacting with climate and growing conditions. Three experiments were carried out on lettuce and Cichorium endivia grown in ebb-and-flow (EF) and floating (FL) systems at two levels of NS salinity (EC = 2.5 and 3.5 dS m−1) (EC2.5, EC3.5, respectively) under autumn and early-spring (lettuce) and winter and late-spring conditions (C. endivia). Nitrogen deprivation (NS withdrawal a few days before the harvest) was tested at EC2.5, in the autumn and winter cycles. The EF-system caused an increase in salinity in the substrate where roots mainly develop so it mimicked the effect of the EC3.5 treatment. In the winter-grown lettuce, the EF-system or EC3.5 treatment was effective in reducing the nitrate level without effects on yield, with the EF baby-leaf showing an improved quality (color, dry matter, chlorophylls, carotenoid, vitamin C, phenol). In both seasons, the EF/EC3.5 treatment resulted in a decline in productivity, despite a further reduction in nitrate content and a rise in product quality occurring. This response was strictly linked to the increasing salt-stress loaded by the EC3.5/EF as highlighted by the concurrent Cl− accumulation. In early-spring, the FL/EC3.5 combination may represent a trade-off between yield, nitrate content and product quality. In contrast, in winter-grown endive/escarole the EC3.5, EF and EC3.5/EF reduced the nitrate level with no effect on yield, product quality or Cl− uptake, thus proving them to be more salt-tolerant than lettuce. High temperatures during the late-spring cycle promoted nitrate and Cl− uptake, overcoming the nitrate-controlling effect of salinity charged by the EF system or EC3.5. The nitrate level decreased after 3 day-long (lettuce) or 6 day-long (C. endivia) NS withdrawal. In C. endivia and EF-grown lettuce, it provoked a decrease in yield, but a concurrent improvement in baby-leaf appearance and nutritional quality. More insights are needed to fine-tune the duration of the NS removal taking into account the soilless system used and species-specific characteristics.
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影响因子：
5.6
作者：
Bonasia A;Lazzizera C;Elia A;Conversa G
通讯作者：
Conversa G
影响因子：
4.3
作者：
Conversa, Giulia;Bonasia, Anna;Elia, Antonio
通讯作者：
Elia, Antonio
影响因子：
4.1
作者：
El-Nakhel, Christophe;Pannico, Antonio;Rouphael, Youssef
通讯作者：
Rouphael, Youssef
影响因子：
4.3
作者：
Debouba, Mohamed;Gouia, Houda;Ghorbel, Mohamed Habib
通讯作者：
Ghorbel, Mohamed Habib
影响因子：
7
作者：
Bonasia, Anna;Conversa, Giulia;Elia, Antonio
通讯作者：
Elia, Antonio