Sudan red 7B staining and soluble sugar quantification

In order to visualize the lipid concentration, 2‐wk‐old Arabidopsis seedlings were drenched in 0.1% (w/v) Sudan red buffer with phenol as solvent. The samples were stained for 5 h at room temperature in darkness, and then the chlorophyll was expelled by washing with 70% (v/v) ethanol for three times. The samples were quickly photographed by a stereo microscope (Olympus MVX10, Tokyo, Japan).

In order to measure the soluble sugar content in Arabidopsis, siliques at 15 DAF were collected and 10 mg of fine powder per sample was used for soluble sugar extraction based on the published method (Bezrutczyk et al., 2018) and the instruction of the Micro Plant Soluble Sugar Content Assay Kit (Solarbio, Beijing, China). The extraction subsequently was subjected to the microplate reader (Tecan infinite M200, Mannedorf, Switzerland) at the wavelength of 620 nm for soluble sugar analysis.