Calibration and Evaluation of a STELLA Software-based Daily CO2 Balance Model in Vitis vinifera L.

Abstract

This paper describes and evaluates the reliability of a model for prediction of daily carbon balance and dry matter (DM) accumulation in vertically shoot positioned grapevine (Vitis vinifera L.) canopies based on the user-friendly STELLA simulation software. Validation of the model was produced for potted 'Cabernet Sauvignon' grapevines at both low canopy density [LD (≈10 shoots/m of row)] and high canopy density [HD (≈20 shoots/m of row)] by comparing, ona seasonal basis, the modelled daily CO 2 balance with the diurnal net carbon exchange rate (NCER) measured using a whole-canopy enclosure method. Estimated daily total photosynthesis (P n ) was linearly correlated with measured NCER for LD (r 2 = 0.87) and HD (r 2 = 0.86), thereby indicating that despite its simplicity the model led to a fairly good degree of precision, although it tended to slightly underestimate (5% to 8% less) the measured rates and scattering increased at high values of CO 2 fi xations. Daily total respiration (R) for LD treatment was 29.0% of total daily P n , with clusters, leaves and stems accounting for 11.8%, 46.7%, and 41.5%, respectively. Daily total R was 24.2% of total daily P n in HD treatment and single organs contributed 22.3% (clusters), 41.6% (leaves), and 36.1% (stems). The model estimated that 1604 and 1893 g DM per vine accumulated at harvest for LD and HD treatment, respectively, whereas destructive sampling of leaves, stems and clusters yielded 1475 ± 64 g per vine for LD treatment and 1730 ± 96 g per vine for HD treatment, respectively, corresponding to the 91% and 92% of the DM estimated with STELLA, which in its present version does not take into account root respiration.

Model-based analysis of sugar accumulation in response to source - sink ratio and water supply in grape (Vitis vinifera) berries

“…Ollat and Gaudillere (2000) reported a mean value of 1.2 mg carbon per gram dry mass per day for cv. Cabernet Sauvignon, and similar values were obtained for other cultivars (Poni et al 2006). Preliminary calculations showed that carbon depletion due to respiration (dRes/dt) is less than 2% of the carbon increment (C fl  dDW/dt), and, therefore, has minimal influence on simulated sugar concentration.…”

“…In most grape cultivars, glucose and fructose predominantly accumulate (Kliewer 1966;Liu et al 2006), although in peach, sucrose is predominant, and followed by glucose and fructose and minor amounts of sorbitol (Wu et al 2003). Based on these differences, the model parameters related to the rate of relative sugar metabolism were reduced from five in the SUGAR model to one, enabling the present model to be readily incorporated into grape models at the canopy scale (Gutierrez et al 1985;Poni et al 2006). The model's reproduction of the sugar concentration response to various conditions confirms that the conceptual framework proposed in the SUGAR model is generally applicable to fleshy fruits.…”

Epidemiology of Grape Anthracnose: Factors Associated with Defoliation of Grape Leaves Infected byElsinoë ampelina

“…Consequently, the primary management schemes consist mostly in applying fungicides weekly or biweekly depending on cultivar susceptibility, history of anthracnose, and frequency of rain. However, leaf removal in the fruiting zone during the summer season is a common cultural practice in several grape producing areas (25). The observations made during this study on the severity of grape anthracnose support other reports on the capacity of E. ampelina to seriously damage grapevines with a maximum percent leaf area diseased of 86% and a maximum percent leaf defoliation of 68% recorded in 2006 (Fig.…”

Climate change impacts and adaptive strategies: lessons from the grapevine

“…The theoretical benefits of dynamic models (Costa et al, 2015;Moriondo et al, 2015) include their ability to capture nonlinear interactions between weather and viticulture, their basis on biological, causal processes and their potential to integrate the effects of climate with other factors including soil profiles, crop management practices, and perhaps most importantly for future climate change scenarios, the effects of elevated CO 2 levels on grapevine growth and development (Bindi et al, 1996;Poni et al, 2006).…”