A B S T R A C TThe objective of this work was to evaluate the yield components and physicochemical characteristics of bunches and berries of new grape varieties for juice elaboration, which were 'Isabel Precoce' (Vitis labrusca L.) and the hybrids 'BRS Carmem', 'BRS Cora' and IAC 138-22 'Máximo' grown onto 'IAC 572' and 'IAC 766' rootstocks under tropical conditions. The yield components (number of bunches and yield per vine, as well as productivity) and the physicochemical characteristics of the bunches and berries of the eight scion-rootstock combinations were evaluated in three seasons. All data were subjected to analysis of variance and principal components analysis. The varieties 'Isabel Precoce', 'BRS Cora' and IAC 138 22 'Máximo' produced high fruit yield, with the number of bunches and yield per vine similar to one another and superior to those of 'BRS Carmem'. Significant differences occurred among varieties in the physicochemical grape characteristics. 'Isabel Precoce' and 'BRS Carmem' grapes had balanced levels of sugar and acid content, and 'BRS Cora' presented large bunches and berries, reaching high soluble solids content despite the high acidity. IAC 138-22 'Máximo' grape also had large bunches but small berries and limited potential in the accumulation of sugars. The 'IAC 766' rootstock resulted in the best performance across all four varieties evaluated, showing maximum results in terms of fruit yield and physicochemical quality attributes of grapes.

The objective of this study is to evaluate the effect of rootstocks on grape production, quality and antioxidant capacity of ‘Niagara Rosada’ grape in two productive cycles. The work was developed in Jundiaí-SP, Brazil (26° 06’ S, 46° 55’ W and an average altitude of 745 m). The experimental design was in randomized blocks with subdivided plots, the plots being represented by the rootstocks and the subplots by the production cycles, with four replications, each consisting of 6 plants. The treatments consisted of a combination of ‘IAC 313 Tropical’, ‘IAC 572 Jales’, ‘IAC 571-6 Jundiaí’, ‘IAC 766 Campinas’ and ‘106-8 Mgt’ as rootstocks and ‘Niagara Rosada’ as graft, and the production cycles were 2013 and 2014. The number of bunches, production and productivity of the vines, the physical characteristics of bunches, berries and stalks and the physicochemical composition of the must (soluble solids content, titratable acidity, pH and the relation soluble solids/titratable acidity) were evaluated in production cycles of 2013 and 2014). The content of chlorophylls, anthocyanins, carotenoids, flavonoids and total phenolic compounds and the antioxidant activity of grapes were also evaluated in grape berries. The rootstocks did not influence the production and physical quality of ‘Niagara Rosada’ grapes. As for the chemical characteristics, rootstocks only had an effect on solids content, and ‘IAC 766’ and ‘106-8 Mgt’ rootstocks promoted higher values of this characteristic. Likewise, the total phenolic compounds and the antioxidant activity of the grapes were not influenced by the studied rootstocks. The vines in 2013 presented higher production and better physical characteristics of the grapes, however, the soluble solids content in this cycle was lower than in 2014.

The objective of this work was to evaluate the phenological characteristics and yield of 'Vênus' grapevine (Vitis labrusca) grafted onto different rootstocks, as well the physicochemical traits of its grapes during the 2013, 2014, and 2015 crop seasons. The evaluated rootstocks were 'IAC 766', 'IAC 572', 'IAC 313' and 'IAC 571-6'. The length of the main phenological stages of the grapevine and its thermal demands were assessed during two growing seasons and expressed as days after pruning and degree-day sum, respectively. Grapevine yield and berry physicochemical characteristics were assessed during three crop seasons. 'Vênus' phenological cycle and thermal demands, as well as the chemical characteristics of its grapes, varied with the climate conditions during the crop seasons. Low temperatures increased the grapevine cycle, and higher rainfall indices caused a decrease in the soluble solids of berries, as well as an increase in their titratable acidity. The 'IAC 766' and 'IAC 571-6' rootstocks promote a greater precocity to 'Venus' grapevines, and 'IAC 572' promotes a higher grapevine yield and better physicochemical characteristics of 'Vênus' grapes.

The aim of this study is to evaluate the phenology, yield and fruit physicochemical characteristics of four persimmon cultivars (Diospyros kaki L.) in São Paulo's Midwest countryside, Brazil. The persimmon cultivars studied were 'Pomelo', 'Rama Forte', 'Fuyu' and 'Rubi'. The main phenological phases of persimmons trees were evaluated. Despite significant differences between cultivars in the early and intermediate stages of the plants development such as branch development, full blossom and fruiting's onset, the time required between the fruit's pruning and harvesting was similar among the cultivars. It could be observed that only 'Pomelo' persimmon trees presented male flowers. However on 'Rubi', 'Fuyu' and 'Rama Forte' persimmons trees were found the largest number of female flowers, fruits fixation index and number of fruits per branch. Nevertheless, there were no differences among the cultivars regarding productivity, which could be due to the persimmon fruits physical characteristics. The fruits' diameter growth behavior was evaluated and it was observed that all cases were defined as double sigmoidal, defined by three single phases. Regarding the chemical characteristics, there were no differences among the cultivars' pH and soluble solids content; however, in general, the 'Pomelo' persimmon fruit presented less titratable acidity and a higher maturation index rating.

Vineyard cultural practices may influence amount of sugars, acids, phenolic compounds and antioxidant activity of grapes. Thus, the purpose of this study was to evaluate the effect of different shoot topping levels on the chemical characteristics of the grapes during its maturation, yield and the physicochemical characteristics and phenolic compounds of 'Niagara Rosada' grapevine grafted onto different rootstocks. The experiment was conducted in a 2-year-old vineyard of Niagara Rosada cultivar in Southeast of Brazil. The vines were trained on a unilateral cordon system in a vertical shoot positioning. The manual shoot topping was carried by leaving 6, 7, 8 or 9 leaves above the last cluster. Vines were topped 60 days after pruning, when the vines were in the beginning of bunch closure. All vines were grafted onto 'IAC 766' and 'IAC 572' rootstocks. Fruit maturation curve, yield and physicochemical grapes characteristics were analyzed to determine the effects of shoot topping levels and rootstocks. The rootstocks and the different shoot topping levels did not influence the yield, productivity and cycle duration of 'Niagara Rosada' grapevines. Larger and heavier clusters and berries were harvested from vines grafted on 'IAC 766' rootstock. However, grapes harvested from grapevines grafted on 'IAC 572' rootstock presented higher total anthocyanins content. The shoot topping carried out with 7 or 8 leaves above the latest cluster provided higher sugars, total polyphenols content and antioxidant activity.