Effect of applications of biostimulants on the productivity and the physicochemical characteristics of 'Isabel'

A.G. Turmina, A.P.F. Lima, A.F. Fagherazzi, A.E. Mario, P.I. Mudrei, M.A. Andrião, L. Rufato
The bioregulators applications provide hormones such as cytokinins, auxins and gibberellins, minimising the effects of biotic and abiotic stresses, generating productivity gains and improved physicochemical characteristics on clusters of grapes. In this sense, the objective of this study was to evaluate the effect of different doses of bioregulator Stimulate® on the physicochemical characteristics of clusters and berries of 'Isabel'. The experiment was conducted in Pinto Bandeira, Rio Grande do Sul, Brazil, during the 2011-2012 harvest. The treatments were (T1) control; (T2) 0.1%; (T3) 0.2%; (T4) 0.3% Stimulate® applied once when the sproutings reached 20 cm (Phase I); (T5) 0.1%; (T6) 0.2%; (T7) 0.3% Stimulate® applied in two seasons, Phase I and grain pellet. The experimental design was a randomised blocks with six repetitions. The variables analysed were productivity, number of berries per cluster, mass of clusters, rachis and berries, berry diameter, length and width of clusters, soluble solids, acidity and total number of green berries per cluster (NGC). The data were subjected to regression analysis using the statistical program WinStat. The variables that were not adjusted significantly to regression test were the following: clusters length with an application, productivity when applied twice, number of fruits and total soluble solids in both applications. With the increase of Stimulate® doses applied two times, a linear increase it was found for width of clusters, berries and diameter of NGC; however, to cluster length, there was a linear decrease. With only one application it was noted that the linear growth of cluster, productivity, berry diameter, bunch width, rachis mass, mass of berries and NGC, adjusted to a significantly positive polynomial quadratic regressions. We conclude that a single application (Phase I) of Stimulate® at doses between 0.2 and 0.3% is sufficient to improve the physicochemical characteristics of clusters, and to increase the productivity of 'Isabel'.
Turmina, A.G., Lima, A.P.F., Fagherazzi, A.F., Mario, A.E., Mudrei, P.I., Andrião, M.A. and Rufato, L. (2017). Effect of applications of biostimulants on the productivity and the physicochemical characteristics of 'Isabel'. Acta Hortic. 1157, 429-432
DOI: 10.17660/ActaHortic.2017.1157.61
Vitis labrusca, grape, fruit quality, productivity, wine, bioregulators

Acta Horticulturae