To examine growth conditions that can increase the critical dietary mineral zinc in leaves of baby leaf red oak lettuce, we investigated zinc accumulation under various conditions, including different zinc concentrations in nutrient solution, wind speeds, and root zone temperatures. A high zinc concentration in the nutrient solution led to greatly increased leaf zinc concentration, but also decreased fresh and dry weights of shoots. In addition, necrosis was observed in leaves at a zinc concentration in the nutrient solution of ≥ 0.15 mM. By contrast, high wind speed and root zone temperature led to increases in leaf zinc concentration, but slightly decreased fresh and dry weights of shoots. In addition, under high wind speed and root zone temperature, no leaf necrosis was observed. The increase in leaf zinc concentration was attributed to increases in zinc absorption, accompanied by increased transpiration, because water absorption rates increased with wind speed and root zone temperature. Therefore, baby leaf red oak lettuce with high leaf zinc concentration can be produced by increasing wind speed and root zone temperature.

中文翻译：

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在风速和根区温度升高的人工照明下生长的水培小生菜的锌生物强化

为了检查可以增加幼叶红橡木生菜叶子中关键膳食矿物质锌的生长条件，我们研究了各种条件下的锌积累，包括营养液中不同的锌浓度、风速和根区温度。营养液中的高锌浓度导致叶片锌浓度大大增加，但也降低了枝条的鲜重和干重。此外，在锌浓度≥ 0.15 mM 的营养液中观察到叶片坏死。相比之下，高风速和根区温度导致叶片锌浓度增加，但嫩梢鲜重和干重略有下降。此外，在高风速和根区温度下，未观察到叶片坏死。叶片锌浓度的增加归因于锌吸收的增加，伴随着蒸腾作用的增加，因为吸水率随着风速和根区温度的增加而增加。因此，可以通过提高风速和根区温度来生产具有高叶锌​​浓度的幼叶红橡生菜。