Quality and antioxidant potential of ‘BRS Magna’ grapes harvested in the first half of the year under different training systems and rootstocks in a tropical region

Abstract

The Submedium São Francisco Valley is renowned for its particular conditions for cultivating grapes for different uses. The production of grapes for juice is relatively recent, and thus, knowledge is still limited on components of the production system. The aim of this study was to characterize the quality and antioxidant activity of ‘BRS Magna’ grapes in irrigated crops of the Submedium São Francisco River Valley under the influence of training systems and rootstocks, in production cycles of the first half of the year. The experiment was conducted in the Experimental Field of Bebedouro/Embrapa Semiárido, in Petrolina, Pernambuco, Brazil. The following were studied: overhead trellis, lyre, and vertical shoot positioning (VSP) systems and rootstocks ‘IAC 572’ and ‘IAC 766’, in the production cycles corresponding to the first halves of 2017 and 2018. Experimental design was in randomized blocks, with sub-subplots through time and four replicates. Overall, responses depended on training systems, rootstocks, and production cycles, which determined specific traits of the grapes. Production in the first half of 2018 was characterized by high anthocyanin contents, high total extractable polyphenols, and higher antioxidant activity, and responses were differentiated according to training system and rootstock. Plants trained to overhead trellis and grafted on ‘IAC 572’ had higher accumulation of total extractable polyphenols and antioxidant activity in berries. Plants trained to VSP had increased sugar, yellow flavonoid, and anthocyanin contents in berries while lyre training system led to higher bunch mass.

Impact of trellis systems and rootstocks on global phenolic composition and antioxidant activity of ‘Isabel Precoce’ grapes produced during rainy seasons in semi-arid region of Brazil

“…The adoption of this rootstock, which is widely recognized for its high vigor in tropical conditions, resulted in the highest soluble solids contents in berries. This might be explained by the higher uptake of light provided by the systems lyre and OTS systems, validating that the rootstock influences bunch quality even if responses vary according to the climatic conditions, scion cultivar, and trellis system adopted (Ferreira et al, 2019;Costa et al, 2021).…”

“…The combination of trellis systems with rootstocks influences the interception of solar radiation (Ferreira et al, 2019) and causes changes in the chemical composition of the grapes. Within certain limits, solar radiation promotes the biosynthesis of anthocyanins, an effect that might be mediated by the positive regulation between radiation and the gene MYBF1, which induces a response of the gene CHS responsible for the synthesis of phenolics (Martínez-Lüscher et al, 2016).…”

Trellis systems and rootstocks affect the quality and antioxidant potential of ‘BRS Cora’ grapes in rainy seasons under semiarid conditions

“…This inferred that 'IAC 766' associated with VSP and OTS allowed sufficient opening of the canopy to ensure enough light incidence to stimulate the synthesis of phenols. Ferreira et al (2019) reported that productive cycles with high temperatures associated with high solar radiation interception during grape ripening showed greater biosynthesis of phenolic compounds, since it is related to exposure of the fruits to stress.…”

“…The major variables affected by the trellis systems and rootstocks were the total extractable polyphenol compound contents, the total anthocyanin contents, the antioxidant activity by the DPPH • method and the color attribute b*, affected by pigments such as the anthocyanins. This response was due to the effect of canopy management on the interception of solar radiation and microclimate around the bunch (Pastore et al 2017), which, in turn, affected pigment synthesis or degradation (Leão and Lima 2018) and that of other phenolic compounds (Ferreira et al 2019). This influence was attributed to the sensitivity of PAL (which catalyzes the reaction in the first phenolic pathway step) to climatic factors such as solar radiation (Wang et al 2015).…”

“…Depending on canopy architecture, the leaves and bunches of the grapevines may develop either in the shade or totally exposed to solar radiation (Pastore et al 2017). Trellis systems influence the level of sunlight exposure on the leaves and can change the grapevine physiology as a consequence of the microclimate around the bunches, affecting the grape composition, including phenolic compound contents (Scafidi et al 2017;Ferreira et al 2019). Conversely, the rootstock may affect the grapevine physiology and phenology, yield, vigor, fertility, berry size and color, also affecting fruit quality (Jin et al 2016; Miele and Rizzon 2017).…”