2022 journal article

Acquisition of Freezing Tolerance in Vaccinium macrocarpon Ait. Is a Multi-Factor Process Involving the Presence of an Ice Barrier at the Bud Base


co-author countries: United States of America πŸ‡ΊπŸ‡Έ
author keywords: bud anatomy; cold acclimation; cold hardiness; freeze dehydration; cranberry (Vaccinium macrocarpon Ait); fruit crop; ice propagation
Source: Web Of Science
Added: June 6, 2022

Bud freezing survival strategies have in common the presence of an ice barrier that impedes the propagation of lethally damaging ice from the stem into the internal structures of buds. Despite ice barriers' essential role in buds freezing stress survival, the nature of ice barriers in woody plants is not well understood. High-definition thermal recordings of Vaccinium macrocarpon Ait. buds explored the presence of an ice barrier at the bud base in September, January, and May. Light and confocal microscopy were used to evaluate the ice barrier region anatomy and cell wall composition related to their freezing tolerance. Buds had a temporal ice barrier at the bud base in September and January, although buds were only freezing tolerant in January. Lack of functionality of vascular tissues may contribute to the impedance of ice propagation. Pith tissue at the bud base had comparatively high levels of de-methyl-esterified homogalacturonan (HG), which may also block ice propagation. By May, the ice barrier was absent, xylogenesis had resumed, and de-methyl-esterified HG reached its lowest levels, translating into a loss of freezing tolerance. The structural components of the barrier had a constitutive nature, resulting in an asynchronous development of freezing tolerance between anatomical and metabolic adaptations.