PT  - JOURNAL ARTICLE
AU  - G. Stanley Howell
AU  - M. Carmo Candolfi-Vasconcelos
AU  - Werner Koblet
TI  - Response of Pinot noir Grapevine Growth, Yield, and Fruit Composition to Defoliation the Previous Growing Season
AID  - 10.5344/ajev.1994.45.2.188
DP  - 1994 Jan 01
TA  - American Journal of Enology and Viticulture
PG  - 188--191
VI  - 45
IP  - 2
4099  - http://www.ajevonline.org/content/45/2/188.short
4100  - http://www.ajevonline.org/content/45/2/188.full
SO  - Am J Enol Vitic.1994 Jan 01; 45
AB  - Leaf removal has been increasingly employed to improve the cluster microclimate. Leaf loss has been suggested to reduce fruitfulness and hardiness of buds at that node. Before such a practice can be accepted in temperate zone climates, the impact on such bud and subsequent growth factors requires critical evaluation. Leaf removal at a point about half way between fruit-set and veraison (berry pea-size or 7 mm diameter) during Year 1 (1989) had minimal impact on main and lateral leaf number or area, vine yield or yield components, or fruit composition values in Year 2 (1990). No defoliation occurred in 1990. One notable exception was the increase in percentage of shootless nodes at positions where leaves had been removed. Node position influenced bud fruitfulness (nodes 1 and 2 had lowest yields) and node 4 (where the basal cluster was commonly produced) consistently was less fruitful than node 3, 5, or 6). It was also significantly more frequently shootless. Further experimentation should be undertaken to assess the impact of leaf removal on bud and cane cold hardiness and fruitfulness suggested by these data in climates where such damage is a persistent viticultural concern.