Silva, E. A.DaMatta, F. M.Ducatti, C.Regazzi, A. J.Barros, R. S.2014-05-202014-05-202004-10-08Field Crops Research. Amsterdam: Elsevier B.V., v. 89, n. 2-3, p. 349-357, 2004.0378-4290http://hdl.handle.net/11449/17589Seasonal changes in vegetative growth, leaf gas exchanges, carbon isotope discrimination (Delta) and carbohydrate status were monitored in de-fruited coffee trees (Coffea arabica L.) grown in the field, from October 1998 through September 1999, in Vicosa (20degrees45'S, 42degrees15'W, 650 m a.s.l.), southeastern Brazil. of the total growth over the 12-month study period, 78% occurred in the warm, rainy season (October-March), and 22% during the cool, dry season (April-September). Throughout the active growth period, the rate of net carbon assimilation (A) averaged 8.6 mumol m(-2) s(-1), against 3.4 mumol m(-2) s(-1) during the period of reduced growth. In the active period, growth, unlike A or Delta, was strongly negatively correlated with air temperature. In contrast, growth and A were both correlated positively, and Delta correlated negatively, with air temperature during the reduced growth period. However, the depressions of A and growth might have simply run in parallel, without any causal relationship. Changes in A appeared to be largely due to stomatal limitations in the active growing season, with non-stomatal ones prevailing in the slow growth period. Foliar carbohydrates seemed not to have contributed appreciably to changes in growth rates and photosynthesis. (C) 2004 Elsevier B.V. All rights reserved.349-357engcarbohydratecarbon isotope discriminationCoffee arabicagas exchangetemperatureArtigo10.1016/j.fcr.2004.02.010WOS:000223676600014Acesso restrito1030251743943217