Initial studies into grape berry temperatures of field-grown vines in Queensland

Abstract

In recent years the focus of much research has been into the effects of light and heat on the composition of wine grapes. Some findings of this research has shown bunch light exposure to negatively impact on accumulation of anthocyanins (Haselgrove et al. 2000; Spayd et al. 2002) and flavonols (Downey et al. 2004) Bunch exposure has also been shown to increase berry temperature above ambient (Spayd et al. 2002). Findings of such research has led to many growers altering cultural practices in order to reduce bunch exposure and bunch temperature with the aim of increasing wine grape quality. Traditionally the method for assessing fruit temperature has been to measure bunch zone temperatures often with sensors and data loggers in situ. Although providing a record of bunch zone temperature this method of temperature logging may not however represent the temperature of the berries themselves. Therefore this project aimed to compare the data recorded by bunch zone temperature data loggers with temperatures of directly exposed grape berries.