Heat stress in grapevine: the pros and cons of acclimation

Abstract

Heat stress is a major limiting factor of grapevine production and quality. Acclimation and recovery are essential to ensure plant survival, and the recovery mechanisms can be independent of the heat response mechanisms. An experimental set up with and without acclimation to heat followed by recovery [stepwise acclimation and recovery (SAR) and stepwise recovery (SR), respectively] was applied to two grapevine varieties, Touriga Nacional (TN), and Trincadeira (TR), with different tolerance to abiotic stress. Major differences were found between leaves of SAR and SR, especially after recovery; in SAR, almost all parameters returned to basal levels while in SR they remained altered. Acclimation led to a swifter and short-term antioxidative response, affecting the plant to a lesser extent than SR. Significant differences were found among varieties: upon stress, TN significantly increased ascorbate and glutathione reduction levels, boosting the cell's redox-buffering capacity, while TR needed to synthesize both metabolites, its response being insufficient to keep the redox state at working levels. TR was affected by stress for a longer period and the up-regulation pattern of antioxidative stress genes was more obvious. In TN, heat shock proteins were significantly induced, but the canonical heat-stress gene signature was not evident probably because no shutdown of the housekeeping metabolism was needed.

Differential physiological response of the grapevine varieties Touriga Nacional and Trincadeira to combined heat, drought and light stresses

“…In control conditions TN had higher levels of total ascorbate than TR, as previously reported (Carvalho et al . ), and slightly higher AsA percentage than TR. Upon the WSHS combination, redox percentage decreased in both varieties, indicating difficulty in maintaining the cellular redox state.…”

“…Control levels of total ascorbate were lower in TR than in TN, as previously described (Carvalho et al . ; Fig. A).…”

“…AsA and dehydroascorbic (DAsA) acids were assayed using a method adapted from Okamura () by Carvalho et al . (). The concentration of DAsA was calculated by subtracting the AsA concentration measured from the total ascorbate determined.…”

Validation of Reference Genes for Quantitative Real-Time PCR during Bicolor Tepal Development in Asiatic Hybrid Lilies (Lilium spp.)

“…To avoid the effect of gDNA contamination, intron-spanning primer pairs are regarded as ideal primers for qRT-PCR analysis (Kosir et al, 2010; Eildermann et al, 2012; Carvalho et al, 2015). Unfortunately, since genomic resources for Lilium spp.…”

Grapevine Biotechnology: Molecular Approaches Underlying Abiotic and Biotic Stress Responses

“…UV-B is not only potentially harmful, but it also serves as an environmental information source, though information about it is still scarce. As general abiotic stresses have been extensively reviewed [119][120][121][122][123][124][125], we will have special focus on UV-B-mediated perception and signalling responses of grapevine and photobiotechnological approaches to improve fruit quality for winemaking.…”