Immunohistochemical dynamics of cell wall matrix polymers during tomato autograft healing

Abstract

A large part of the production of tomato plants is grafted. Although it has recently been described that cell walls play an important role in tomato graft healing, the spatiotemporal dynamics of cell wall changes in this critical process remains largely unknown. The aim of this work was to immunolocalize changes in the major cell wall matrix components of autograft union tissues throughout the course of healing, from 1 to 20 days after grafting (DAG). Homogalacturonan was de novo synthetized and deposited in the cut edges, displaying the low methyl-esterified homogalacturonan a stronger labelling. Labelling of galactan side chains of rhamnogalacturonan increased until 8 DAG, although remarkably a set of cells at the graft union did not show labelling for this epitope. Changes in xylan immunolocalization were associated to the xylem vasculature development throughout, while those of xyloglucan revealed early synthesis at the cut edges. Arabinogalactan proteins increased up to 8 DAG and showed scion-rootstock asymmetry, with a higher extent in the scion. The combination of these changes appears to be related with the success of the autograft, specifically facilitating the adhesion phase between scion-rootstock tissues. This knowledge paves the way for improved grafting using methods that facilitate appropriate changes in the time and space dynamics of these cell wall compounds.

Cell wall anisotropy plays a key role in Zea mays stomatal complex movement: the possible role of the cell wall matrix

“…Immunolocalization of HG epitopes: LM20 (Verhertbruggen et al 2009 ; Frey et al 2023 ); JIM7 (Knox et al 1990 ); JIM5 (Knox et al 1990 ; Frey et al 2023 ); 2F4 (Liners et al 1989 ) and xyloglucans (LM15) (Marcus et al 2008 ) was carried out in hand-made paradermal sections of fresh leaf tissue, which were initially fixed in 4% (w/v) paraformaldehyde (PFA) in PEM buffer (50 mm PIPES [piperazine-N,N′-bis(2-ethanesulphonic acid)], 5 mm EGTA, 5 mm MgSO4, pH 6.8) for 45 min. Following fixation, the sections were washed three times with PEM for 15 min and treated with 2% (w/v) cellulase (Onozuka R-10 [Yakult Honsha Co. L, Tokyo, Japan]) in PEM, pH 5.6, for 60 min.…”

Non‐invasive monitoring of tomato graft dynamics using thermography and fluorescence quantum yields measurements

“…The formation of the graft union is a dynamic and continuous phenomenon involving a complex series of events at the physiological, cellular and molecular levels that are necessary to ensure the successful union between rootstock and scion (Fernández-García et al, 2004;Frey et al, 2022Frey et al, , 2023Melnyk et al, 2015). In addition, grafting is an important research tool for understanding how different physiological mechanisms are coordinated in a wide range of plants (Notaguchi et al, 2020;Reeves et al, 2022).…”