Cold stress triggers premature fruit abscission through ABA-dependent signal transduction in early developing apple
Fig 2
Morphological changes of an excised Hongro/M9 apple tree subunit after ex vivo cold shock followed by 168 hr of incubation at 25 °C.
(a) Comparison of pedicel tissues containing the abscission zone (AZ) (left: normal, before the incubation; middle: treatment, cold shock followed by the incubation; right: control, after the incubation). (b) Transmission electron microscopy images of the AZ cortical cells at proximal tissues in the pedicel (top: cold treatment, 168 hr of incubation following initial 2 hr of cold shock; bottom: control, 168 hr after incubation without cold shock). Samples were observed with a LIBRA 120 transmission electron microscope at an acceleration voltage of 120 kV, magnification of 4 k (left, middle) and 6.3 k (right). Arrows indicate the development of cytoplasmic vesicles.