| SS Description
|
Seeds of lettuce “Grand Rapids (Leaf Lettu … Seeds of lettuce “Grand Rapids (Leaf Lettuce Green)” (Lactuca sativa L. var crispa) and “King Crown” (Lactuca sativa L. var capitata) were purchased from SAKATA SEED CORPORATION (Kanagawa, Japan). The seeds were germinated on vermiculite as a support medium in pots. The plants were grown in a growth chamber (12 h light/12 hr dark, 22 C) for 33 days and then on a cultivation shelf (16 hr light/ 8 hr dark, 20-28 C). The leaves were harvested 77 and 83 days after germination for Leaf Lettuce Green and King Crown, respectively. The plants were fertilized using a solution containing 3 mM KNO3, 1 mM Ca(NO3)2, 0.5 mM MgSO4, 0.5 mM NH4H2PO4, 0.05 mM Fe(III)-ethylenediamine-N,N,N’,N’-tetraacetic acid (EDTA), 49 uM H3BO3, 9 uM MnSO4, 0.8 uM ZnSO4, 0.3 uM CuSO4, and 0.1 uM Na2MoO4. For the stable isotope labeling, KNO3, Ca(NO3)2, and NH4H2PO4 were replaced with their 15N labeled chemicals (99.2-99.8 Atom%) and MgSO4 was replaced with its 34S labeled chemical (98 Atom%). labeled chemicals were purchased from Shoko Science Co., Ltd. (Yokohama, Japan). The plants were fertilized properly using the same amount of the solution in one time for control, 15N-labeled, and 34S-labeled plants. In total, 2,530 and 3,040 mL of the solution was used for growing three individuals of Leaf Lettuce Green and King Crown, respectively. The shoot of three individuals for each treatment was harvested, mixed, weighed, and homogenated using mortar and pestle under liquid nitrogen into a fine powder. The sample was stored at -80 C until use. A part of the powdered sample was freeze-dried and stored at room temperature. eeze-dried and stored at room temperature.
|
