PT  - JOURNAL ARTICLE
AU  - Brittany L. Komm
AU  - Michelle M. Moyer
TI  - Effect of Early Fruit-Zone Leaf Removal on Canopy Development and Fruit Quality in Riesling and Sauvignon blanc
AID  - 10.5344/ajev.2015.15007
DP  - 2015 Sep 03
TA  - American Journal of Enology and Viticulture
PG  - ajev.2015.15007
4099  - http://www.ajevonline.org/content/early/2015/08/31/ajev.2015.15007.short
4100  - http://www.ajevonline.org/content/early/2015/08/31/ajev.2015.15007.full
AB  - Canopy management is vital for quality wine grape (Vitis vinifera) production. During the 2012 and 2013 growing seasons, the timing of fruit-zone leaf removal (FZLR) was evaluated in two commercial vineyard blocks (V. vinifera ‘Riesling’ and ‘Sauvignon blanc’) located north of Prosser, WA. Three different timings of manual FZLR were evaluated relative to a no removal control. Leaf removal consisted of complete removal of all leaves and lateral shoots in the fruiting-zone on both sides of the canopy at the specified times of pre-bloom, bloom and 4 weeks post-bloom. Each vine received the same treatment for both years of the study. No negative implications were observed in total fruit set in either year of the study. When leaf removal was performed, regardless of timing the fruit-zone of the canopy had less lateral shoot development and canopy refill than the control. Leaf removal also improved spray coverage in the fruit-zone in Riesling, but the effect was related to the timing of when leaf removal had occurred relative to the timing of the spray. In 2013, pre-bloom leaf removal resulted in significantly reduced Botrytis bunch rot severity in Sauvignon blanc relative to the control (p = 0.01) and the 4 weeks post-bloom leaf removal treatments. In 2013, pre-bloom leaf removal in Riesling increased terpene concentrations in the harvest juice relative to the control (p = 0.03). While in 2012, post-bloom leaf removal in Riesling reduced concentration of acids relative to pre-bloom (p = 0.04) in the harvest juice.