JA | Jasmonic acid

Immunodetection of JA (green fluorescence) and red autofluorescence of chloroplasts in leaves during senescence. (A–C) Leaves control (LC); (D–F) The first stage of leaf senescence (LS1); (G–I), The second stage of leaf senescence (LS2). Abbreviations: VB, vascular bundle; PM, palisade mesophyll; SM, spongy mesophyll; E, epidermis. Scale bars = 50 µm.

Immunolocalization of JA (green fluorescence) in fine, absorptive roots during senescence. (A,B), Root control (RC); (C,D) The first stage of root senescence (RS1); (E,F) The second stage of root senescence (RS2). Autofluorescence (red) of the cell wall was recorded to visualize the cell and/or organ shape. Abbreviations: R, rhizodermis; C, parenchyma cortex cells; Ph, phloem; X, xylem. Scale bars = 50 µm.

Drought upregulates the level of jasmonic acid (JA) in the abscission zone (AZ) of yellow lupine flowers. AZ fragments were collected for these analyses from 48 day-old plants subjected to drought (25% water holding capacity, WHC) or lupines cultivated in the soil of optimal moisture (70% WHC, control). Details in the Material and Methods section. The level of JA was examined using GC-MS (A). A significant difference is ** p < 0.01. Immunolocalization of JA in the AZ of control (B) or stressed (C,D) plants. Green fluorescence is related to JA localization (indicated by red arrows), whereas blue color corresponds to DAPI-stained nuclei. AZ area is marked by white dotted lines (B,C). (D) image is magnified AZ area presented on C. Abbreviations: AZ—abscission zone; D—distal region of AZ; P—proximal region of AZ. Bars = 40 µM.