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The estimate of the photosynthetic response to temperature is important for accurate growth predictions in process-based models designed to respond to broad variation in environmental conditions. Several studies have attempted to decipher the temperature and mesophyll response functions for use in the widely used Farquhar et al. (1980) biochemically based photosynthesis model. Unfortunately, published values of Rubisco kinetic properties (Kc and Ko) differ among species. To compound the problem, the methodology used to estimate Kc and Ko has not been consistent. We compared the variation in carbon gain estimates of a whole tree by incorporating the different temperature parameter estimates of Bernacchi et al. (2001, 2003) and Medlyn et al. (2002) into a three-dimensional biological process-based model. In addition, we also investigated the contribution of mesophyll conductance by incorporating Rubisco enzyme kinetics parameters reported by Bernacchi et al. (2002). Temperature parameters substantially influenced our whole tree carbon gain estimates. The variation among model estimates of aboveground net carbon gain was ≈11% for 3-year-old red maple saplings. Variation was even greater when mesophyll conductance was incorporated. The different parameter estimates, if not validated at the whole plant scale, can introduce inaccuracies and exacerbate carbon gain estimates of single plants, stands of plants, and entire ecosystems.

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Association, Hillegom, The Netherlands, and the Jac. Th. de Vroomen Bulb Co. of Lisse, The Netherlands, for the special handling of the crowns. Use of trade names does not imply endorsement of the products named nor criticism of similar ones not named. The

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1 Professor of Vegetable Crops. Florida Agr. Expt. Sta. Journal Series no. R-00261. Rhubarb crown divisions provided by Nourse Farms, South Deerfield, Mass., and `Victoria' seedlings by Hunsader Farms, Bradenton

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prevention of electrolyte leakage may be major determinants of ice encasement resistance and recuperative ability. Ice encasement was shown to reduce total nonstructural carbohydrate levels in crown tissues of winter wheat due to 7 d of ice encasement ( Gao

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More than 10 species of Phytophthora de Bary are reported to affect cultivated Prunus L. worldwide, causing root rot, crown rot, trunk and scaffold cankers, and even fruit rots ( Browne and Doster, 2002 ; Browne and Mircetich, 1995 ; Félix

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A variety of techniques and vegetative materials are used to asexually propagate blackberry. Blackberry plants can be easily reproduced from root suckers, crown division, root cuttings, tip layering, soft stem cuttings, and tissue culture (TC

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1930s, anthracnose crown rot caused by C. fragariae and C. gloeosporioides has been a destructive disease in strawberry nurseries and fruit-production fields in the southeastern United States ( Brooks, 1931 ). In 1986, the presence of the

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block design with four replications. The whole-plot treatments were randomized and consisted of three biodegradable mulch products: BioAgri, Crown 1, and SB-PLA-11 ( Table 1 ). Two subplot soil treatments, mulched and bare ground, were applied in the

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floral primordia in eastern thornless blackberry (e.g., ‘Triple Crown’) are not visible until spring ( Takeda et al., 2002 ; Takeda and Wisniewski, 1989 ). The presence of an actively growing shoot tip is necessary during the first 3 or 4 d after the

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