Not All Shrivels Are Created Equal—Morpho-Anatomical and Compositional Characteristics Differ among Different Shrivel Types That Develop during Ripening of Grape (<i>Vitis vinifera</i> L.) Berries

Abstract

An understanding of physiological disorders associated with ripening of fruits triggered by abiotic stress relies on anatomical and physico-chemical analyses, as it provides insights into their origin and probable causes. The objective of this study was to analyze different ripening disorders of grape (Vitis vinifera L.) berries by dissecting their morphoanatomy, shriveling nature, and composition. Four well-defined disorders-sunburn, prolonged dehydration (PD), lateseason bunch stem necrosis (LBSN), and berry shrivel (BS) were analyzed in field-grown grapevines of the cultivar Cabernet Sauvignon. Early bunch stem necrosis (EBSN) that occurred before ripening was also included in the study. Unlike healthy spherical berries, the pericarp of disordered berries except for sunburn shriveled causing concomitant reductions in fresh weight and volume. The exocarp of PD berries developed well-ordered indentations as distinct from the wrinkles in LBSN berries, whereas BS berries were flaccid with numerous skin folds. The epicuticular wax occurred as upright platelets in all shrivel forms excluding the sun-exposed hemisphere of sunburned berries. A chlorophyllous inflorescence framework persisted in all shrivel forms but in LBSN, wherein the necrotic regions developed tylosis. Unlike the translucent mesocarp of healthy, sunburned, and PD berries, the mesocarp was collapsed in BS and LBSN berries, nevertheless all had well-developed seeds. The composition of healthy berries was optimal, whereas the disordered berries were compositionally distinct from each other, which as a whole differed from the healthy berries. The BS berries had the lowest sugar content, and although sugar concentration was higher in LBSN, sunburned and PD berries, sugar amount per berry was highest in the healthy berries, the same was true for hexoses. Healthy and BS berries exhibited highest amounts of tartaric acid followed by sunburn and PD berries, whereas the LBSN berries had the lowest values. Conversely, healthy and PD berries had the highest amounts of malic acid followed by LBSN, sunburn and BS berries, which collectively displayed similar amounts. The PD berries exhibited the highest calcium content followed by LBSN, healthy, and finally BS and sunburned berries. A linear relationship existed between potassium (K) and pH of the berries. The PD berries had the highest amounts of K followed by healthy, sunburn, LBSN, and BS berries. Overall, the results reported here provided combined morpho-anatomical and compositional analyses of different shrivel types that occurred during a single growing season. Such analysis is needed to make a progress on understanding these ripening disorders culminating in the development of remedial measures.

Grape berry position affects the diurnal dynamics of its metabolic profile

“…1 | INTRODUCTION Fruits exposed to excessive solar radiation and elevated air temperatures face the risk of oxidative damage, sunburn, and pericarp dehydration (Bondada & Keller, 2012;Greer & Weedon, 2013;Racsko & Schrader, 2012;Torres, Andrews, & Davies, 2006) with potential negative implications on seed dispersal (Allen & Lee, 1992;Garcia, Zamora, Gomez, & Hodar, 1999;Martin, 1985). To counter these degrading processes, fruits have complex protection mechanisms, which include the accumulation of compounds conferring potent reactive oxygen species (ROS) scavenging activity, osmotic adjustment, and ultraviolet B (UV-B) radiation screening.…”

Understanding Differential Responses of Grapevine (Vitis vinifera L.) Leaf and Fruit to Water Stress and Recovery Following Re-Watering

“…On the other hand, if the water deficit prolonged, then the ripening berries will certainly shrivel via dehydration as in that case the xylem efflux plus berry transpiration will exceed phloem influx [49]. Another scenario for grape berries to shrivel include when berries develop various physiological disorders associated with ripening [61][62][63]. Many of these disorders are characterized by cell death rendering the cell membranes non selective [62,64].…”

Using foliar applications of magnesium and potassium to improve yields and some qualitative parameters of vine grapes (Vitis vinifera L.)

“…These disorders appear as a loss of turgor and lower sugar content in the grape berries; at the same time increasing the content of acids (Bondada and Keller 2012). This causes degradation of the quality of grape production all over the world; nonetheless the cause of these disorders has not yet been fully clarified, yet (Knoll et al 2010).…”