“Effect of elevated temperature on the onset and rate of mesocarp cell death in berries of Shiraz and Chardonnay and its relationship with berry shrivel”
Marcos Bondada (University of Adelaide – INTA Argentina); Victor Sadras (SARDI) and
Sigfredo Fuentes (University of Adelaide – University of Melbourne)
Australian Journal of Grape and Wine Research.
This paper show results of the effect of elevated temperature on the dynamics of berry cell death and shrivel for two varieties: Shiraz and Chardonnay.
These two varieties have contrasting dynamics of berry cell death and shrivel. The first can reach important levels of Shrivel at harvest with moderate mesocarp cell death in berries, while Chardonnay reaches high levels of cell death with minimal shrivelling symptoms.
Figure 1: Differences between Shiraz and Chardonnay in cell death and shrivel. Bright sections of the mesocarp corresponds to living tissue and dark areas to dead tissue. Images obtained using FDA stain (Fuentes et al. 2010).
Elevated temperature accelerated both mesocarp cell death and berry shrivelling in Shiraz and accelerated mesocarp cell death but had no impact on shrivel in Chardonnay. Mesocarp cell death seems necessary but not sufficient to explains berry shrivelling. Awareness of functional links between berry shrivel and mesocarp cell death, and the environmental modulation of these traits would likely contribute to management practices that could reduce the severity of shrivel in a context of warmer conditions.
Figure 2: Time-trajectory of mesocarp cell death. for Shiraz berries in the study of Tilbrook and Tyerman (2008). The bilateral model fitted to the data (eq. 2) has three biologically relevant parameters: (the onset of rapid cell death), b1 (slope before the onset) and b2 (slope after the onset).