ETHEPHON SPRAYS AS A DEFOLIANT IN ‘NIAGARA ROSADA’ VINE SUBJECTED TO TWO CROP PRODUCTION PER YEAR

Thiago Vieira Da Costa,Rafaela Vieira Façanha,João Alexio Scarpare Filho

doi:10.1590/0100-29452016297

Thiago Vieira Da Costa, Rafaela Vieira Façanha + Show 1 more

Open Access

https://doi.org/10.1590/0100-29452016297

Copy DOI

Abstract

ABSTRACT In climate region Cwa of the State of São Paulo the technique of double cropping the grapevine is possible, however, when it is time for the second pruning of the crop, most of the vine’s leaves are still in the plant, posing the problem that the use of ethephon as a defoliant could increase leaf senescence and improve the vine management. The objective of this study was to evaluate the effects of ethephon spray as a defoliant in the development and production of the ‘Niagara Rosada’ vine when subjected to double cropping, and the influence this bioactivator may have on carbohydrate reserves in the branch. The experiments were conducted in a commercial, non-irrigated area in agricultural years of 2011/2012 and 2012/2013. The length, diameter and total carbohydrate reserves of the branches, as well as bud break, number of clusters, crop production, length, width and mass of cluster, berry diameter, soluble solids and titratable acidity were evaluated. Ethephon treatments were applied at a concentration of 1,440 mg L-1 and 2,160 mg L-1 at 20 and 15 days before pruning. As a control, the vines were defoliated by hand at the time of pruning. A randomized block experimental design was used. Data was subjected to analysis of variance and means were compared by the Tukey test at 5% significance level. In conclusion, we propose that ethephon sprays promoted vine defoliation and improved the bud break, altered plant development and crop production. This was not due to increases in concentration of carbohydrate reserves in the branches, but due to a higher induction stimulus of bud break, which allowed the vines to express their higher yield capacity.

Highlights

The State of São Paulo produces about 147,000 tons of grapes, standing out as one of the largest table grape growers of Brazil
In Cwa climate conditions, production pruning of ‘Niagara Rosada’ grape is traditionally held in the winter and the harvest occurs between the months of December and January
Winter pruning is known as dry pruning as plants are defoliated and the pruning is performed in the phase of reserve mobilization with a short pruning (SCARPARE et al, 2011)

Summary

Introduction

The State of São Paulo produces about 147,000 tons of grapes, standing out as one of the largest table grape growers of Brazil. In this context, the ‘Niagara Rosada’ vines correspond to 51% of total State production (IEA, 2014), and is mainly grown in Aw climates (Jales region) and Cwa (Jundiaí). Winter pruning is known as dry pruning as plants are defoliated and the pruning is performed in the phase of reserve mobilization with a short pruning (with one or two buds) (SCARPARE et al, 2011) The producers from this region adopted the summer production pruning, known as green pruning because the plants are leafy. This pruning is carried out in the summer, during the phase of reserve accumulation and is considered long, because the branches are pruned in the fourth or fifth bud (SCARPARE et al, 2011)

Objectives

Methods

Results

Conclusion