TY - JOUR
T1 - Early defoliation (hand vs mechanical) for improved crop control and grape composition in Sangiovese (Vitis vinifera L.)
AU - Intrieri, C.
AU - Filippetti, I.
AU - Allegro, G.
AU - Centinari, M.
AU - Poni, S.
PY - 2008/4/1
Y1 - 2008/4/1
N2 - Background and Aims: The number of pre-bloom source leaves is a primary determinant of subsequent fruitset. Accordingly, we tested whether pre- and post-bloom hand (HD) and mechanical (MD) defoliation are effective in limiting the yield of a high-cropping cultivar such as Sangiovese in a 3-year field study. Methods and Results: The first six basal leaves and any laterals were removed by hand, and the same area was subjected to MD, the latter removing 48.3% of the leaf area removed manually. Both treatments significantly reduced fruitset, yield per shoot, bunch weight, berries per bunch and bunch compactness. Yield/ha declined from 32.8 tons in control vines to 24.4 and 19.0 tons for MD and HD (pre- and post-bloom treatment means), respectively. Leaf-to-fruit ratios were unaffected by defoliation as source loss was fully offset by yield decline. Soluble solid concentration and total anthocyanins on a fresh-weight basis increased by 2.4°Brix and 0.2 mg/g in HD and by 2.2°Brix and 0.08 mg/g in MD as compared with that in non-defoliated control. Conclusions: Although results from HD reinforce the physiological basis of the technique's effectiveness, MD proved likewise effective in reducing yield and improving grape quality. Significance of the Study: Early MD has the potential to regulate yield in a timely and cost-effective fashion.
AB - Background and Aims: The number of pre-bloom source leaves is a primary determinant of subsequent fruitset. Accordingly, we tested whether pre- and post-bloom hand (HD) and mechanical (MD) defoliation are effective in limiting the yield of a high-cropping cultivar such as Sangiovese in a 3-year field study. Methods and Results: The first six basal leaves and any laterals were removed by hand, and the same area was subjected to MD, the latter removing 48.3% of the leaf area removed manually. Both treatments significantly reduced fruitset, yield per shoot, bunch weight, berries per bunch and bunch compactness. Yield/ha declined from 32.8 tons in control vines to 24.4 and 19.0 tons for MD and HD (pre- and post-bloom treatment means), respectively. Leaf-to-fruit ratios were unaffected by defoliation as source loss was fully offset by yield decline. Soluble solid concentration and total anthocyanins on a fresh-weight basis increased by 2.4°Brix and 0.2 mg/g in HD and by 2.2°Brix and 0.08 mg/g in MD as compared with that in non-defoliated control. Conclusions: Although results from HD reinforce the physiological basis of the technique's effectiveness, MD proved likewise effective in reducing yield and improving grape quality. Significance of the Study: Early MD has the potential to regulate yield in a timely and cost-effective fashion.
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U2 - 10.1111/j.1755-0238.2008.00004.x
DO - 10.1111/j.1755-0238.2008.00004.x
M3 - Article
AN - SCOPUS:41849104588
SN - 1322-7130
VL - 14
SP - 25
EP - 32
JO - Australian Journal of Grape and Wine Research
JF - Australian Journal of Grape and Wine Research
IS - 1
ER -