The breakdown of the primary cell wall and degradation of pectic polysaccharides in the middle lamella regions of abscission zone cells are the main events during plant organ abscission. This protocol provides an efficient procedure for detecting the contents of different pectin epitopes by antibodies including LM5 (immunolocalization of (1–4)-β-D-galactan epitopes), LM6 (immunolocalization of (1–5)-α-L-arabinan epitopes), JIM5 (immunolocalization of homogalacturonan (HG) with a low degree of methylesterification epitopes), and JIM7 (immunolocalization of HG with a high degree of methylesterification epitopes).