The variate “cluster weight” is an important Vitis vinifera vine yield component and its main subcomponents are berry number and berry weight ( Clingeleffer et al., 2000 ). This variate's values can be affected by factors that include scion
Michael E. Tarter and Stefano Poni
Stefano Poni, Alberto Palliotti, and Fabio Bernizzoni
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, on a seasonal basis, the modelled daily CO2 balance with the diurnal net carbon exchange rate (NCER) measured using a whole-canopy enclosure method. Estimated daily total photosynthesis (Pn) 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 CO2 fixations. Daily total respiration (R) for LD treatment was 29.0% of total daily Pn, with clusters, leaves and stems accounting for 11.8%, 46.7%, and 41.5%, respectively. Daily total R was 24.2% of total daily Pn 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.
Susana Boso Alonso, Virginia Alonso-Villaverde Pilar Gago, José L. Santiago, Mariá C. Martínez, and Emilio Rodriguez
The grapevine cultivar Albariño ( Vitis vinifera L.) has long been grown in northwestern Spain and the north of Portugal. The approval of the Appellation Contrôlée (A.C) “Rías Baixas” denomination in northwestern Spain in 1988 ( Ministerio de
Cassandra M. Plank, Edward W. Hellman, and Thayne Montague
MPs are a class of aroma compounds responsible for vegetal aromas in fruit of some Vitis vinifera L. wine grape cultivars. MPs have been quantified in Grenache ( López et al., 1999 ), Merlot ( Sala et al., 2000 ), Cabernet Franc ( Allen et al
Fucheng Shan and Kevin Seaton
propagation techniques. Materials and Method Plant materials and preparation All the plant propagation materials were maintained in pots in a greenhouse at the Department of Agriculture and Food, Western Australia, South Perth. The grapevines ( Vitis vinifera
Wanmei Jin, Jing Dong, Yuanlei Hu, Zhongping Lin, Xuefeng Xu, and Zhenhai Han
a widely grown fruit crop in the world. ‘Centennial Seedless’ of Vitis vinifera L. is one of the most widely grown grape varieties in China because it is suitable for both table consumption and wine production ( Kong, 2004 ). The berries of the
D.W. Ramming, R.L. Emershad, P. Spiegel-Roy, N. Sahar, and I. Baron
Immature grape embryos from early ripening genotypes of Vitis vinifera were successfully cultured in vitro on Difco orchid agar or a modified White's agar medium. Germination was increased in vitro for five genotypes from 0%, 7%, 11%, 12%, and 16% in vivo to 15%, 24%, 23%, 34%, and 24%, respectively. Subculturing embryos onto liquid culture from seeds that failed to germinate on agar also was possible. Differences in germination rates, as affected by pollen, were significant. This method will allow accelerated development of early ripening cultivars by allowing breeders to use such genotypes as females, as well as males.
F.J. Montero, J.A. de Juan, A. Cuesta, and A. Brasa
The importance of rapid, nondestructive, and accurate measurements of leaf area (LA) in agronomic and physiological studies is well known, but a search of the literature revealed little information available for grape (Vitis vinifera L.). The results described herein include a comparison of 12 different mathematical models for estimating leaf area in `Cencibel'. The simplest, most accurate regression equations were: LAi = 0.587 LW (R 2 = 0.987) and LAi = 0.588 LW (R 2 = 0.994), where LAi is leaf area measured using image analysis and LW is leaf length × maximum width. Use of maximum width (W), leaf length (L), petiole length (Lp), and dry weight of leaves (DML) as single variables in the regression equations were not as closely associated with total leaf area, although their R 2 values were also highly significant.
Danielle Lo Giudice, Tony K. Wolf, and Richard P. Marini
Prohexadione-calcium (prohexadione-Ca) was evaluated for its ability to suppress vegetative growth of grapevines (Vitis vinifera L.) under field conditions. Two or three applications of 250 mg·L-1 prohexadione-Ca reduced primary shoot growth of `Cabernet Sauvignon', but had little effect on other canopy characteristics or cane pruning weights. The reduction of shoot growth was not persistent and shoot hedging was ultimately needed to avoid canopy shading. Similarly, three applications of either 125, 250, or 375 mg·L-1 prohexadione-Ca reduced `Cabernet franc' shoot growth, but again did not eliminate the need for shoot hedging. Cane pruning weights of `Cabernet franc' were unaffected by treatment, and canopy characteristics were generally not improved. Two prebloom and one postbloom application of 250 mg·L-1 prohexadione-Ca were evaluated on `Cabernet franc' and `Chardonnay' in separate field experiments. The prebloom treatments retarded shoot growth of `Chardonnay', but had no effects on `Cabernet franc' shoot characteristics. To retard shoot growth, prohexadione-Ca had to be applied prior to bloom; however, prebloom applications had the potential for severe reductions in crop yield.
R. Scorza, J.M. Cordts, D.J. Gray, D. Gonsalves, R.L. Emershad, and D.W. Ramming
Transgenic grape plants were regenerated from somatic embryos derived from leaves of in vitro-grown plants of `Thompson Seedless' grape (Vitis vinifera L.) plants. Somatic embryos were either exposed directly to engineered Agrobacterium tumefaciens or they were bombarded twice with 1-μm gold particles and then exposed to A. tumefaciens. Somatic embryos were transformed with either the lytic peptide Shiva-1 gene or the tomato ringspot virus (TomRSV) coat protein (CP) gene. After cocultivation, secondary embryos proliferated on Emershad/Ramming proliferation (ERP) medium for 6 weeks before selection on ERP medium containing 40 μg·mL-1 kanamycin (kan). Transgenic embryos were identified after 3 to 5 months under selection and allowed to germinate and develop into rooted plants on woody plant medium containing 1 μm 6-benzylaminopurine, 1.5% sucrose, 0.3% activated charcoal, and 0.75% agar. Integration of the foreign genes into these grapevines was verified by growth in the presence of kanamycin (kan), positive β-glucuronidase (GUS) and polymerase chain-reaction (PCR) assays, and Southern analysis.