PHYTOREGULATORS ON BUD FERTILITY AND CLUSTER QUALITY OF ‘THOMPSON SEEDLESS’ GRAPES GRAFTED ONTO ‘RAMSEY’ ROOTSTOCK

The objective of this work was to evaluate the influence of Trinexapaque-ethyl (TrixE) and benzyladenine (BA) on the fertility of buds and the quality of bunches of „Thompson Seedless‟ grapes grafted onto „Ramsey‟ rootstock, in the Vale São do Francisco. The experimental design consisted of randomized blocks with 16 treatments (doses and number of applications of the plant regulators TrixE and BA), with four replications, each composed of three plants, with one plant per plot. The variables analyzed were: overall potential bud fertility, potential of the basal, median and apical branches of the plant; fertility of potential buds from the basal region of the basal and median branches; fertility of overall real buds, and of the median and apical branches; diameter of the basal, median and apical branches; Falker chlorophyll index a, b and total; sprouting buds, number of clusters per branch, clusters per plant, branches per plant; berry diameter, length, volume; fresh material mass; soluble solids content (SS), titratable acidity (AT) and SS/AT relationship; diameter, length, mass of fresh material from the clusters; shatter, fresh material mass of the rachis and rachis diameter . It was shown that the TrixE applied in isolation , one, two or three times in doses of 20 mg L-1, or associated with BA in a single application of 120 or 240 mg L-1, increased the rate of real fertility, but did notaffect the length of the clusters or the vegetative vigor of the plants

EVALUATION OF NITROGEN MONITORING, BUD FERTILITYAND ‘THOMPSON SEEDLESS’ GRAPEVINE PRODUCTION ON DIFFERENT ROOTSTOCKS

<div><p>ABSTRACT Methods of nitrogen analysis were adopted in leaf tissues in the laboratory, nitrate content in the sap of petioles and chlorophyll relative index (CRI, in SPAD unit), as well as the evaluation of the buds fertility rates, production and qualitative aspects of cluster and berries of ‘Thompson Seedless’ vine, grafted on rootstocks ‘Harmony’, ‘Jales’ ‘Paulsen 1103’ and ‘SO4’. The applied dose of N was 80 kg ha-1, and the experiment was installed in the Submédio do Vale do São Francisco, Brazil. The experiment was performed in a randomized blocks design, with four treatments and five replicates, with the experimental plot represented by five plants. In addition to the analysis of N, cluster length and width (cm) and fresh mass (g), berries length, diameter (mm), volume (mL), mass of fresh matter of berries, soluble solids (SS), titratable acidity (TA), SS/TA ratio, potential bud fertility (productive, vegetative, dead and dark buds in %) and real bud fertility (%). There were differences in nitrogen content in the leaves, nitrate in sap and CRI of ‘Thompson Seedless’ in relation to rootstocks. ‘Thompson Seedless’ expressed better potential for the development of clusters and berries when grafted on ‘Harmony’.</p></div