How Pretest Temperatures Change the Cold Hardiness of Grapevine (Vitis ViniferaL. Cv. Karaerik) Dormant Buds?

Abstract

The aim of this study was to confirm the hypothesis that pretest temperature changes could alter the cold hardiness of the grapevine dormant buds and eventually the result of differential thermal analysis (DTA) test. For this reason, dormant buds of 'Karaerik' grape cultivar were collected at different times and tested using different DTA procedures. Dormant buds taken at nine different sampling temperatures (8, 6, 5, 3, −1, −3, −4, −5, and −9°C) were exposed to freezing test according to three DTA test approaches (TestA-A, TestA-4 and Test20-4, to represent ambient storage and ambient test, ambient storage and 4°C test, and 20 ± 2°C storage and 4°C test or standard DTA method, respectively) to verify our hypothesis in 2015-16 and 2016-17. The LTE (low temperature exotherm) temperatures were determined as the indicator of death of primary buds at grapevines' dormant buds, tested according to TestA-A approach, TestA-4 approach and Test20-4 approach (the standard methodology). It was found that temperature changes such as rapid cooling, warming and thawing in the TestA-4 approach, and warming-cooling and melting-cooling in the Test20-4 approach altered LTE values of dormant buds depending on the test start temperature. It was determined that the LTE values of dormant buds tested according to TestA-4 and Test20-4 approaches were higher than that of the ones tested with TestA-A approach. Compared to TestA-A approach, the LTE values of dormant buds were between 0.00 and 4.00°C in the TestA-4 approach and 0.00 and 2.77°C in the Test20-4 approach based on temperature changes. As a result, to achieve reliable, and consistent LTE results at DTA tests, it was determined that dormant buds should be brought into laboratory by keeping the temperatures at the sampling time, prepared for test at these temperatures and to start DTA test from these temperatures is a right approach.

Temperature Shift Between Vineyards Modulates Berry Phenology and Primary Metabolism in a Varietal Collection of Wine Grapevine

“…For instance, under controlled environment, heat treatment (28 • C/18 • C day/night) hastened sugar accumulation rate and significantly shortened the ripening length (Martínez-Lüscher et al, 2016b). In other studies, heat was reported to slow berry ripening in Semillon (Greer and Weedon, 2013) and in Muscat Hamburg (Carbonell-Bejerano et al, 2013). However, most of the studies investigating temperature effects on berry ripening focused on a single or very few cultivars, which may explain the unequivocal results.…”

“…The fruit-ripening phase, from véraison to harvest, determines the sugar/acid balance and engustment in the developing berry (Van Leeuwen et al, 2019;Morales-Castilla et al, 2020). Opposite to milder climates as Bordeaux, where longer and warmer growing seasons provide greater ripening potential (Jones and Davis, 2000), an extended fruit-ripening phase under the much higher temperature regime characterizing arid regions might lead to disorder in sugar accumulation, phenylpropanoid degradation, and sunburns (Greer and Weedon, 2013;Pastore et al, 2017). Under temperate climate regions, warmer seasons were associated with a shortened ripening phase (Tomasi et al, 2011;Alikadic et al, 2019).…”

Evaluation of Sample Preparation Practices Common with Differential Thermal Analysis of Grapevine Bud Cold Hardiness

“…A common criticism of studies conducting DTA involves the temperature at the time of sample collection and the time taken during processing (Kaya and Kose 2020). If sample collection and preparation is not done rapidly, and samples are not maintained at the same temperature as experienced during collection, then rapid deacclimation would shift observed cold hardiness values.…”

“…Dehydration of collected canes can also alter LTE measurements, shifting them lower as dehydration increases over time (Kovacs et al 2002). While some studies have looked at the potential for collection temperature to have a meaningful impact on DTA analysis, most focused on storage conditions that are well-above typical storage and transport temperatures (i.e., 20°C versus 0 or 4°C) and extrapolate those findings to apply to all pre-processing storage conditions (e.g., Kaya and Kose 2020). Understanding the true impact of these factors on the accuracy and precision of DTA could improve the efficiency of sample collection and might also facilitate development of DTA "centers" to process out-of-area samples.…”

Sprayed biodegradable liquid film improved the freezing tolerance of cv. Cabernet Sauvignon by up-regulating soluble protein and carbohydrate levels and alleviating oxidative damage

“…Low temperature stress is one of the most important abiotic stresses, adversely affecting plant growth and development, restricting the geographic distribution of plant species, and reducing global crop yields ( Lv et al., 2010 ; Kaya, 2020a ; Kaya and Kose, 2020 ; Kaya, 2020b ). Plants have evolved sophisticated mechanisms to withstand cold stress, such as cold acclimation, a process by which plants acquire increased freezing tolerance upon prior exposure to nonlethal low temperature ( Guy, 1990 ; Thomashow, 1999 ; Chinnusamy et al., 2007 ).…”