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The literature describes the belowground and aboveground phenology of potato to be linearly related. Bud formation is synchronous with tuber initiation and flowering with tuber filling. Many agronomic and breeding studies on potato use non‐destructive aboveground phenology to assess belowground development. No information is currently available on the influence of water deficit on the synchrony of above‐ and belowground development in potato. Five contrasting potato genotypes were subjected to four irrigation treatments on two different soil types. The irrigation treatments were as follows: fully watered, early drought, intermediate drought, and late drought. In 5‐day intervals after withholding water, detailed belowground and aboveground development was recorded. Results showed that the synchrony between aboveground and belowground development is strongly influenced by both water deficit and development stage at drought initiation. Under early drought, the aboveground development was hastened and belowground development was delayed. The opposite was found in later development stages. The earlier the drought was initiated, the longer the tuber filling phase was, while the bulking phase was shortened. We concluded that under terminal drought conditions aboveground development and belowground development need to be evaluated separately and cannot follow the standard evaluation system that uses aboveground phenology as a proxy for tuber formation belowground development rates. [ABSTRACT FROM AUTHOR]

In the present study, the fluctuations in fatty acids, tocopherols, organic acids, and free sugars content of cardoon blades collected at sixteen harvest dates (samples B1–B16, corresponding to principal growth stages (PGS) between 1 and 9) were evaluated. A total of 26 fatty acids were identified, with palmitic (C16:0, 19.9–40.13%), α-linolenic (C18:3n3, 6.39–33.2%), and linoleic (C18:2n6c, 9–34.8%) acids being present in higher relative abundances in most of the samples, while lipid content was the highest in samples of late (B15) and intermediate (B8–B10) stages of maturity. The α- and γ-tocopherols were the only detected vitamin E isoforms, while α-isoform presented the highest concentration (80–8567 µg/100 g dw) in all the studied samples, except for samples B9–B11, for which the γ-tocopherol was detected in higher concentrations. Moreover, samples B1 and B14 showed the highest content of total tocopherols (8352 and 10,197 µg/100 g dw, respectively). The identified organic acids were oxalic, quinic, malic, citric, and fumaric. Malic acid was present in higher concentrations in almost all the samples analyzed, except for samples B3 and B15, in which the presence of oxalic acid stood out. Regarding the free sugar's composition, fructose, glucose, sucrose, trehalose, and raffinose were the only detected compounds, with sucrose being present in higher concentrations in almost all the samples (1.662–10.8 g/100 g dw), while samples at younger maturation stages, namely samples B4 and B5, presented the highest concentrations of total sugars. In conclusion, the obtained results demonstrate the influence that the growth cycle may have on the chemical composition of this tissue (blades) of the species. Moreover, having a more complete knowledge regarding its composition and identifying the stage of maturation which is most appropriate for obtaining a greater amount of certain bioactive compounds will help to increase the added value of this multi-purpose crop. [ABSTRACT FROM AUTHOR]

In the present study, the fluctuations in fatty acids, tocopherols, organic acids, and free sugars content of cardoon blades collected at sixteen harvest dates (samples B1–B16, corresponding to principal growth stages (PGS) between 1 and 9) were evaluated. A total of 26 fatty acids were identified, with palmitic (C16:0, 19.9–40.13%), α-linolenic (C18:3n3, 6.39–33.2%), and linoleic (C18:2n6c, 9–34.8%) acids being present in higher relative abundances in most of the samples, while lipid content was the highest in samples of late (B15) and intermediate (B8–B10) stages of maturity. The α- and γ-tocopherols were the only detected vitamin E isoforms, while α-isoform presented the highest concentration (80–8567 µg/100 g dw) in all the studied samples, except for samples B9–B11, for which the γ-tocopherol was detected in higher concentrations. Moreover, samples B1 and B14 showed the highest content of total tocopherols (8352 and 10,197 µg/100 g dw, respectively). The identified organic acids were oxalic, quinic, malic, citric, and fumaric. Malic acid was present in higher concentrations in almost all the samples analyzed, except for samples B3 and B15, in which the presence of oxalic acid stood out. Regarding the free sugar’s composition, fructose, glucose, sucrose, trehalose, and raffinose were the only detected compounds, with sucrose being present in higher concentrations in almost all the samples (1.662–10.8 g/100 g dw), while samples at younger maturation stages, namely samples B4 and B5, presented the highest concentrations of total sugars. In conclusion, the obtained results demonstrate the influence that the growth cycle may have on the chemical composition of this tissue (blades) of the species. Moreover, having a more complete knowledge regarding its composition and identifying the stage of maturation which is most appropriate for obtaining a greater amount of certain bioactive compounds will help to increase the added value of this multi-purpose crop.