GiESCO 2019 banner
IVES 9 IVES Conference Series 9 GiESCO 9 GiESCO 2019 9 Late leaf removal does not consistently delay ripeningin semillon in Australia

Late leaf removal does not consistently delay ripeningin semillon in Australia


Context and purpose of the study ‐ An advancement of grapevine phenological development has been observed worldwide in the last two decades. In South Australia this phenomenon is even more accentuated since grapevine is often grown in a hot climate. The main consequences are earlier harvests at higher sugar levels which also result in more alcoholic wines. These are deemed undesirable for the Australian wine industry with consumer preferences shifting towards lower alcohol wines. Vineyard practices can be implemented to control and delay ripening. Amongst them, apical late leaf removal has been successfully applied in Europe to delay ripening by up to two weeks in Sangiovese, Aglianico and Riesling. In those studies, no negative effects were observed on grape colour, phenolics and on the carbohydrate storage capacity of the vines. To date, this technique has not been studied in Australia. In this study late leaf removal, apical to the bunch zone was applied to the variety Semillon for four seasons and compared to an untreated control.

Material and methods ‐ The study was carried out for four consecutive seasons starting in 2015 in the variety Semillon at the Waite Campus, University of Adelaide, Australia. Yield, yield components and berry chemistry (total soluble solids, titratable acidity, pH and total phenolics) were all assessed during the study.

‐ Results showed that despite the removal of up to 30% of the vine’s canopy, the technique was effective in delaying ripening only in one of the four seasons. No differences were observed in yield components and berry and wine chemistry between the treated and untreated vines. These results suggest that the technique might not be a feasible strategy to delay ripening in Semillon grown in a hot climate in Australia.


Publication date: June 19, 2020

Issue: GIESCO 2019

Type: Article


Roberta DE BEI (1), Xiaoyi WANG (1), Lukas PAPAGIANNIS (1), Massimiliano COCCO (1,3), Patrick O’BRIEN (1), Marco ZITO (1,4), Jingyun OUYANG (1), Sigfredo FUENTES (5), Matthew GILLIHAM (1,2), Steve TYERMAN (1,2) and Cassandra COLLINS (1)

(1) The University of Adelaide, School of Agriculture, Food and Wine, Waite Research Institute, PMB 1 Glen Osmond, 5064, South Australia. Australia
(2) ARC Centre of Excellence in Plant Energy Biology, Waite Research Institute, PMB 1 Glen Osmond, 5064, South Australia, Australia
(3) The University of Sassari, Department of Agriculture, Viale Italia 39, 07100, Sassari, Italy
(4) Istituto di Scienze della Vita, Sant’Anna School of Advanced Studies, Piazza dei Martiri della Libertà 33, 56127 Pisa, Italy
(5) The University of Melbourne, Faculty of Veterinary and Agricultural Sciences. Parkville, 3010. Victoria, Australia

Contact the author


Leaf removal, delayed ripening, canopy management, leaf area, Semillon


GiESCO 2019 | IVES Conference Series


Related articles…

Physiological and growth reaction of Shiraz/101-14 Mgt to row orientation and soil water status

Advanced knowledge on grapevine row orientation is required to improve establishment, management and outcomes of vineyards on terroirs with different environmental conditions (climate, soil, topography) and in view of a future change to more extreme climatic conditions. The purpose of this study was to determine the combined effect of row orientation, plant water status and ripeness level on the physiological and viticultural reaction of Shiraz/101-14 Mgt.

Effects of mechanical leafing and deficit irrigation on Cabernet Sauvignon grown in warm climate of California

San Joaquin Valley accounts for 40% of wine grape acreage and produces 70% of wine grape in California. Fruit quality is one of most important factors which impact the economical sustainability of farming wine grapes in this region. Due to the recent drought and expected labor cost increase, the wine industry is thrilled to understand how to improve fruit quality while maintaining the yield with less water and labor input. The present study aims to study the interactive effects of mechanical leafing and deficit irrigation on yield and berry compositions of Cabernet Sauvignon grown in warm climate of California.

The effects of cane girdling on berry texture properties and the concentration of some aroma compounds in three table grape cultivars

The marketability of the table grapes is highly influenced by the consumer demand; therefore the market value of the table grapes is mainly characterized by its berry size, colour, taste and texture. Girdling could cause accumulation of several components in plants above the ringing of the phloem including clusters and resulting improved maturity. The aim of the experiments was to examine the effect of girdling on berry texture characteristics and aroma concentration.

Application of a fluorescence-based method to evaluate the ripening process and quality of Pinot Blanc grape

The chemical composition of grape berries at harvest is one of the most important factors that should be considered to produce high quality wines. Among the different chemical classes which characterize the grape juice, the polyphenolic compound, such as flavonoids, contribute to the final taste and color of wines. Recently, an innovative non-destructive method, based on chlorophyll fluorescence, was developed to estimate the phenolic maturity of red grape varieties through the evaluation of anthocyanins accumulated in the berry skin. To date, only few data are available about the application of this method on white grape varieties.

Different yield regulation strategies in semi-minimal-pruned hedge (SMPH) and impact on bunch architecture

Yields in the novel viticulture training system Semi-Minimal-Pruned Hedge (SMPH) are generally higher compared to the traditional Vertical Shoot Positioning (VSP). Excessive yields have a negative impact on the vine and wine quality, which can result in substantial losses in yield in subsequent vintages (alternate bearing) or penalties in fruit quality. Therefore yield regulation is essential. The bunch architecture in SMPH differs from VSP. Generally there is a higher amount but smaller bunches with lower single berry weights in SMPH compared to VSP.