Fig. 4. Spatial-based detection of ethylene in sections of Asian pears induced with either an ethylene-stimulating or ethylene-inhibiting additive.

a Scheme of the ethylene biosynthetic pathway in plants. Addition of ACC, the metabolite directly preceding ethylene biosynthesis, will stimulate ethylene production. Addition of PZA, a known inhibitor of ACC oxidase, will decrease ethylene production. b Cotton balls soaked in specific solutions (water, ACC, or PZA) are gently applied to sections of Asian pears. To minimize diffusion, five cotton balls are applied with equal spacing to the surface of pear sections. Four of them contain water, while one of them has been soaked in either 10 mM ACC or 10 mM PZA. c Fluorescent imaging of an Asian pear section where the inner area has been exposed to 10 mM PZA. d Fluorescent imaging of an Asian pear section where the inner area has been exposed to 10 mM ACC. e Summary of measured fluorescence between the outer and inner areas of Asian pear sections that have been supplemented with either ACC or PZA. Multiple images were obtained at ×4 magnification and were joined together via image stitching. Statistical analysis was performed using a one-way ANOVA with Tukey’s multiple comparisons test. *P < 0.03, **P < 0.002, ***P < 0.0002, ****P < 0.0001, ns = not significant. Error is represented as s.d. of three independent experiments. Source data are provided as a Source Data file.