Inheritance of Budbreak and Correlation with Early Height Growth in White Spruce (Picea glauca) from New England

Science.gov (United States)

Ronald C. Wilkinson

1977-01-01

Variation in budbreak date among 37 half-sib families of white spruce in a replicated one-parent progeny test plantation in southern Maine was only 5 days. Differences in the mean date of budbreak between years were greater than those between families, but the genetic correlation between date of budbreak in different years was .661. Heritability estimates ranged from ....

Evaluation of winter temperatures on apple budbreak using grafted twigs

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Fernando José Hawerroth

2013-09-01

Full Text Available Temperature is the main climate factor related to induction, maintenance and dormancy release in apple (Malus domestica Borkh.. The inadequate chilling exposure in apples causes budbreak problems, resulting in decrease in yield potential. Thus, the knowledge of physiological principles and environmental factors determining the dormancy phenomenon, especially winter temperature effects, it is necessary for the efficient selection of cultivars in a productive region. In addition, it is indispensable to adapt the orchard management aiming to decrease the problems caused by lack chilling during winter. The objective of this study was to evaluate the influence of different thermal conditions during the dormancy period on budbreak of apple cultivars. One-year-old twigs of 'Castel Gala' and 'Royal Gala' cultivars, grafted on M7 rootstock, were submitted to temperatures of 5, 10 and 15ºC for different exposure periods (168; 336; 672; 1,008 and 1,344 hours. After treatments execution, the plants were kept in a greenhouse at 25ºC. Budbreak was quantified when accumulated 3,444; 6,888; 10,332; 13,776; 17,220 and 20,664 GDHºC after temperature treatments. The cultivars responded differently to temperature effect during the winter period. The temperature of 15ºC during winter shows a greater effectiveness on 'Castel Gala' apple budbreak while in the 'Royal Gala' apples the temperatures of 5 and 10ºC show better performance. 'Castel Gala' cultivar (low chilling requirement may supply its physiological necessities, may be capable to budburst, even when subjected to higher temperatures in relation to 'Royal Gala' apples (high chilling requirement.

Biological methods for assessment of budbreak in apple trees for modeling dormancy

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Rafael Anzanello

2014-06-01

Full Text Available A biological method was developed to evaluate the dormancy state of apple buds under controlled conditions. Cuttings (20-25 cm long of ‘Castel Gala’ and ‘Royal Gala’ were sampled during the winter period, evaluating different cold and heat regimes to induce budbreak. Contrasts were tested in plant material processing (single node x intact cuttings, cold storage method to break dormancy in incubator chambers (planted in pots with floral foam x wrapped in plastic film, vertically or horizontally and budbreak method in plant growth chambers (base immersed in water x planted in floral foam. Intact cuttings stored vertically in the cold represented better the natural interactions between buds than single node cuttings. Budbreak of lateral buds was strongly influenced by apical dominance. Wrapping cuttings in plastic film optimized internal space usage in the incubators and the number of evaluated buds, compared to planting cuttings in pots. During the warm period in the growth chambers, intact cuttings on floral foam resulted in better bud preservation and survival throughout the evaluation period, compared to cuttings with bases immersed in water. The most suitable conditions to evaluate dormancy evolution in apple buds used plastic-wrapped intact cuttings stored vertically during the cold period, with budbreak evaluation in the warm period after planting the cuttings in floral foam. Standardization of methodology helps to obtain better results in the development of physiological models of dormancy.

Nut crop yield records show that budbreak-based chilling requirements may not reflect yield decline chill thresholds

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Pope, Katherine S.; Dose, Volker; Da Silva, David; Brown, Patrick H.; DeJong, Theodore M.

2015-06-01

Warming winters due to climate change may critically affect temperate tree species. Insufficiently cold winters are thought to result in fewer viable flower buds and the subsequent development of fewer fruits or nuts, decreasing the yield of an orchard or fecundity of a species. The best existing approximation for a threshold of sufficient cold accumulation, the "chilling requirement" of a species or variety, has been quantified by manipulating or modeling the conditions that result in dormant bud breaking. However, the physiological processes that affect budbreak are not the same as those that determine yield. This study sought to test whether budbreak-based chilling thresholds can reasonably approximate the thresholds that affect yield, particularly regarding the potential impacts of climate change on temperate tree crop yields. County-wide yield records for almond ( Prunus dulcis), pistachio ( Pistacia vera), and walnut ( Juglans regia) in the Central Valley of California were compared with 50 years of weather records. Bayesian nonparametric function estimation was used to model yield potentials at varying amounts of chill accumulation. In almonds, average yields occurred when chill accumulation was close to the budbreak-based chilling requirement. However, in the other two crops, pistachios and walnuts, the best previous estimate of the budbreak-based chilling requirements was 19-32 % higher than the chilling accumulations associated with average or above average yields. This research indicates that physiological processes beyond requirements for budbreak should be considered when estimating chill accumulation thresholds of yield decline and potential impacts of climate change.

Fenologia, brotação de gemas e produção de frutos de macieira em resposta à aplicação de cianamida hidrogenada e óleo mineral Phenology, budbreak and apple fruit production by hydrogen cyanamide and mineral oil application

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Fernando José Hawerroth

2009-01-01

Full Text Available A aplicação de indutores de brotação é uma das principais estratégias de manejo utilizadas para minimizar os problemas da falta de frio em frutíferas de clima temperado. Em razão da influência dos indutores de brotação sobre a resposta produtiva das plantas, a mensuração de seus efeitos ao longo do ciclo produtivo torna-se importante. Assim, o presente trabalho foi desenvolvido no ciclo 2007/2008, em Caçador/SC, objetivando avaliar diferentes combinações de cianamida hidrogenada e óleo mineral sobre a fenologia, brotação de gemas e produção de frutos em macieiras. O delineamento experimental foi em blocos casualizados, com seis repetições compostas de uma planta, seguindo arranjo fatorial (5x2, com cinco níveis de indutor de brotação (1. testemunha; 2. óleo mineral 3,2%; 3. óleo mineral 3,2% + cianamida hidrogenada 0,20%; 4. óleo mineral 3,2% + cianamida hidrogenada 0,39%; 5. óleo mineral 3,2% + cianamida hidrogenada 0,59% e duas cultivares (Imperial Gala e Fuji Suprema. A aplicação dos indutores de brotação antecipou e reduziu o período de florescimento, aumentando a coincidência de florescimento das cultivares Imperial Gala e Fuji Suprema. Os indutores de brotação uniformizaram e aumentaram a brotação de gemas axilares e terminais, obtendo-se máxima brotação na cultivar Imperial Gala com 0,44% de cianamida hidrogenada e 3,2% de óleo mineral. O aumento da concentração de cianamida hidrogenada revelou a tendência de diminuir a frutificação efetiva. Observaram-se respostas diferenciadas entre tratamentos quanto à produção e à massa média dos frutos, podendo ser atribuídas ao predomínio da produção de frutos em distintas estruturas de frutificação.The budbreak promoters application is one of main management strategies used to decrease the problems of insufficient winter chilling on temperate fruit trees. Because the influence of budbreak promoters on productive behaviour of plants

Contrasting growth phenology of native and invasive forest shrubs mediated by genome size.

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Fridley, Jason D; Craddock, Alaä

2015-08-01

Examination of the significance of genome size to plant invasions has been largely restricted to its association with growth rate. We investigated the novel hypothesis that genome size is related to forest invasions through its association with growth phenology, as a result of the ability of large-genome species to grow more effectively through cell expansion at cool temperatures. We monitored the spring leaf phenology of 54 species of eastern USA deciduous forests, including native and invasive shrubs of six common genera. We used new measurements of genome size to evaluate its association with spring budbreak, cell size, summer leaf production rate, and photosynthetic capacity. In a phylogenetic hierarchical model that differentiated native and invasive species as a function of summer growth rate and spring budbreak timing, species with smaller genomes exhibited both faster growth and delayed budbreak compared with those with larger nuclear DNA content. Growth rate, but not budbreak timing, was associated with whether a species was native or invasive. Our results support genome size as a broad indicator of the growth behavior of woody species. Surprisingly, invaders of deciduous forests show the same small-genome tendencies of invaders of more open habitats, supporting genome size as a robust indicator of invasiveness. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

How does synchrony with host plant affect the performance of an outbreaking insect defoliator?

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Fuentealba, Alvaro; Pureswaran, Deepa; Bauce, Éric; Despland, Emma

2017-08-01

Phenological mismatch has been proposed as a key mechanism by which climate change can increase the severity of insect outbreaks. Spruce budworm (Choristoneura fumiferana) is a serious defoliator of North American conifers that feeds on buds in the early spring. Black spruce (Picea mariana) has traditionally been considered a poor-quality host plant since its buds open later than those of the preferred host, balsam fir (Abies balsamea). We hypothesize that advancing black spruce budbreak phenology under a warmer climate would improve its phenological synchrony with budworm and hence increase both its suitability as a host plant and resulting defoliation damage. We evaluated the relationship between tree phenology and both budworm performance and tree defoliation by placing seven cohorts of budworm larvae on black spruce and balsam fir branches at different lags with tree budburst. Our results show that on both host plants, spruce budworm survival and pupal mass decrease sharply when budbreak occurs prior to larval emergence. By contrast, emergence before budbreak decreases survival, but does not negatively impact growth or reproductive output. We also document phytochemical changes that occur as needles mature and define a window of opportunity for the budworm. Finally, larvae that emerged in synchrony with budbreak had the greatest defoliating effect on black spruce. Our results suggest that in the event of advanced black spruce phenology due to climate warming, this host species will support better budworm survival and suffer increased defoliation.

Altitudinal variation in growth, bud break and susceptibility to balsam twig aphid damage of balsam fir from 6 Vermont seed sources

Science.gov (United States)

Ronald C. Wilkinson; Paul G. Schaberg

1992-01-01

Differences in 10-year heights, 4-year growth from 1987 through 1990, relative timing of budbreak and damage by the balsam twig aphid (Mindarus abietinus Koch.) among balsam fir (Abies balsamea (L.) Mill.) from 6 Vermont seed sources originating from different elevations were examined. Height differences among seed sources were...

Comparison of Simulated Stem Temperatures and Observed Air Temperatures with Observed Stem Growth in Forest Openings

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Brian E. Potter; Terry Strong

2002-01-01

Phenology, the study of how plant or animal developmental stages relate to the organism's surrounding climate, is a well established discipline with roots dating back more than 2000 years (Hopp and Blair, 1973). For example, correlations are often noted between budbreak or first blossom and integrated air temperature (commonly referred to as heat sums.) The...

Biology, spread, and biological control of winter moth in the eastern United States

Science.gov (United States)

Joseph Elkinton; George Boettner; Andrew Liebhold; Rodger. Gwiazdowski

2015-01-01

The winter moth (Operophtera brumata L.; Lepidoptera: Geometridae) is an inchworm caterpillar that hatches coincident with bud-break on its hosts and feeds on a wide range of deciduous trees. It is one of a group of geometrid species that feed in early spring and then pupate in the top layer of the soil or litter beginning in mid-May. As postulated...

Effects of formaldehyde-enriched mists on Pseudotsuga menziesii (Mirbel) Franco and Lobaria pulmonaria (L.) Hoffm.

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Muir, P S; Shirazi, A M

1996-01-01

The atmosphere in some areas is polluted with formaldehyde (HCHO); however, little is known about effects of HCHO on plants at concentrations resembling those in polluted areas. The effects of simulated fogwater enriched with HCHO on seedlings of Pseudotsuga menziesii (Mirbel) Franco (Douglas fir) and pendants of Lobaria pulmonaria (L.) Hoffm. were assessed. Plants were treated with HCHO-enriched fog (target concentrations of 100, 500, and 1000 microm) during five 4-night mist sessions. Growth and nitrogenase activity (acetylene reduction rate) for lichens and growth and timing of bud-break for Douglas fir were monitored. Nitrogenase activity was lowest in lichens treated at the highest HCHO concentration after all but the first mist session, and it declined significantly with increasing HCHO concentration after the final mist session (R(2) = 0.60, p = 0.02). However, differences in nitrogenase activity among treatments were generally not statistically significant (most p values from ANOVAs were >/= 0.20). Formaldehyde did not affect growth of the lichens. Budbreak of Douglas firs was slightly delayed and height growth was slightly depressed with increasing HCHO concentration, although effects were not statistically significant.

Climate Change and Crop Exposure to Adverse Weather: Changes to Frost Risk and Grapevine Flowering Conditions.

Science.gov (United States)

Mosedale, Jonathan R; Wilson, Robert J; Maclean, Ilya M D

2015-01-01

The cultivation of grapevines in the UK and many other cool climate regions is expected to benefit from the higher growing season temperatures predicted under future climate scenarios. Yet the effects of climate change on the risk of adverse weather conditions or events at key stages of crop development are not always captured by aggregated measures of seasonal or yearly climates, or by downscaling techniques that assume climate variability will remain unchanged under future scenarios. Using fine resolution projections of future climate scenarios for south-west England and grapevine phenology models we explore how risks to cool-climate vineyard harvests vary under future climate conditions. Results indicate that the risk of adverse conditions during flowering declines under all future climate scenarios. In contrast, the risk of late spring frosts increases under many future climate projections due to advancement in the timing of budbreak. Estimates of frost risk, however, were highly sensitive to the choice of phenology model, and future frost exposure declined when budbreak was calculated using models that included a winter chill requirement for dormancy break. The lack of robust phenological models is a major source of uncertainty concerning the impacts of future climate change on the development of cool-climate viticulture in historically marginal climatic regions.

Genotypic differences in architectural and physiological responses to water restriction in rose bush

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Li-Marchetti, Camille; Le Bras, Camille; Relion, Daniel; Citerne, Sylvie; Huché-Thélier, Lydie; Sakr, Soulaiman; Morel, Philippe; Crespel, Laurent

2015-01-01

The shape and, therefore, the architecture of the plant are dependent on genetic and environmental factors such as water supply. The architecture determines the visual quality, a key criterion underlying the decision to purchase an ornamental potted plant. The aim of this study was to analyze genotypic responses of eight rose bush cultivars to alternation of water restriction and re-watering periods, with soil water potential of -20 and -10 kPa respectively. Responses were evaluated at the architectural level through 3D digitalization using six architectural variables and at the physiological level by measuring stomatal conductance, water content, hormones [abscisic acid (ABA), auxin, cytokinins, jasmonic acid, and salicylic acid (SA)], sugars (sucrose, fructose, and glucose), and proline. Highly significant genotype and watering effects were revealed for all the architectural variables measured, as well as genotype × watering interaction, with three distinct genotypic architectural responses to water restriction – weak, moderate and strong – represented by Hw336, ‘Baipome’ and ‘The Fairy,’ respectively. The physiological analysis explained, at least in part, the more moderate architectural response of ‘Baipome’ compared to ‘The Fairy,’ but not that of Hw336 which is an interspecific hybrid. Such physiological responses in ‘Baipome’ could be related to: (i) the maintenance of the stimulation of budbreak and photosynthetic activity during water restriction periods due to a higher concentration in conjugated cytokinins (cCK) and to a lower concentration in SA; (ii) a better resumption of budbreak during the re-watering periods due to a lower concentration in ABA during this period. When associated with the six architectural descriptors, cCK, SA and ABA, which explained the genotypic differences in this study, could be used as selection criteria for breeding programs aimed at improving plant shape and tolerance to water restriction. PMID

The Fate of Aspen in a World with Diminishing Snowpacks

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Kavanagh, K.; Link, T. E.; Seyfried, M. S.; Kemp, K. B.

2010-12-01

Aspen (Populus tremuloides) productivity is tightly coupled with soil moisture. In the mountainous regions of the western USA, annual replenishment of soil moisture commonly occurs during snowmelt. Therefore, snow pack depth and duration can play an important role in sustaining aspen productivity. The presence of almost 50 years of detailed climate data across an elevational transect in the Reynolds Creek Experimental Watershed (RCEW) in southwestern Idaho offers a novel opportunity to better understand the role of shifting precipitation patterns on aspen productivity. Over the past 50 years, the proportion of the precipitation falling in the form of snow decreased by almost a factor of 2 at mid to low elevations in the RCEW, coupled with a roughly four week advance of snow ablation, and decline of large snow drifts that release moisture into the early summer. Results from growth ring increment, stable isotope analysis, sapflux and a process model (Biome BGC), will be used to determine the impact of shifting precipitation patterns on tree productivity along this transect over the past 50 years. Aspen trees located on moist microsites continue to transpire water and maintain high stomatal conductance 21 days later in the growing season relative to individuals on drier microsites. Predictions of net primary productivity (NPP) in aspen are very sensitive to precipitation patterns. NPP becomes negative as early as day 183 (90 days post budbreak) for years with little winter and spring precipitation whereas, in years with ample winter and spring precipitation, NPP remains positive until day 260 when leaf fall occurs. These results give unique insight into the conditions that deciduous tree species will encounter in a warming climate where snow water equivalent continues to diminish and soil moisture declines soon after budbreak occurs.

Effects of different plastic sheet coverings on microclimate and berry ripening of table grape cv "Matilde"

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Vittorino Novello

2000-06-01

Full Text Available Two types of plastic cover (LDPE + EVA and LDPE + HDPE were tested to assess their radiometric properties and the influence on the vegetative and reproductive performances of ‘Matilde’ table grape. Films showed the same transmittance to short infrared waves, but LDPE + EVA had a higher transmissivity to visible, PAR and short infrared wavelength ranges of solar radiation, especially as for the « direct » light component. In comparison to the open field, covering increased GDD accumulation and advanced budbreak by 12 days (LDPE + HDPE or 20 days (LDPE + EVA. Commercial ripening (14 °Brix was advanced by 8 and 22 days, respectively. Must acidity was higher in open field than under LDPE + EVA. Yield per vine increased under LDPE + EVA, although not at a significant level; bunch mass was higher under LDPE + EVA than in open field. Berry mass was maximum under LDPE + EVA and progressively decreased under LDPE + HDPE and in open field. Under covering, the pruning cane mass increased by 63% with LDPE + EVA and 43% with LDPE + HDPE.

Effect of grapevine latent buds (Vitis vinifera L., cv. Merlot chilling on their starch content: biochimical and cytological approachs

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Tayeb Koussa

2001-12-01

Full Text Available Biochimical analysis and photonic microscopy observations of starch were investigated in latent buds of Vitis vinifera L. (cv. Merlot collected during their dormancy phase and during their cold storage at 2°C. Biochimical analysis showed that starch levels of grapevine latent buds was high (70 mg/g DW. Microscopical observations confirmed this result and showed a gradient of starch content in different regions of bud in which the foliars primordiums and scales were the starch richer. Buds conservation at 2°C reduced their starch content but this decrease begun only after 9 days of chilling corresponding to the time necessary for budbreak and for the beginning of increase the bud burst ability. The hydrolysis of starch seems begun at the first in apex and then propaged to the other regions of bud. In the scales, the most exposed region to cold, storage at 2°C during 56 days induced an increase of cellular tannins content and cell walls polysaccharides. These results were discuted in relation to the increase of bud burst ability and to their cold acclimatation.

Adaptation of lodgepole pine and interior spruce to climate: implications for reforestation in a warming world.

Science.gov (United States)

Liepe, Katharina J; Hamann, Andreas; Smets, Pia; Fitzpatrick, Connor R; Aitken, Sally N

2016-02-01

We investigated adaptation to climate in populations of two widespread tree species across a range of contrasting environments in western Canada. In a series of common garden experiments, bud phenology, cold hardiness, and seedling growth traits were assessed for 254 populations in the interior spruce complex (Picea glauca, P. engelmannii, and their hybrids) and for 281 populations of lodgepole pine (Pinus contorta). Complex multitrait adaptations to different ecological regions such as boreal, montane, coastal, and arid environments accounted for 15-20% of the total variance. This population differentiation could be directly linked to climate variables through multivariate regression tree analysis. Our results suggest that adaptation to climate does not always correspond linearly to temperature gradients. For example, opposite trait values (e.g., early versus late budbreak) may be found in response to apparently similar cold environments (e.g., boreal and montane). Climate change adaptation strategies may therefore not always be possible through a simple shift of seed sources along environmental gradients. For the two species in this study, we identified a relatively small number of uniquely adapted populations (11 for interior spruce and nine for lodgepole pine) that may be used to manage adaptive variation under current and expected future climates.

Characterising willows for biomass and phytoremediation: growth, nitrogen and water use of 14 willow clones under different irrigation and fertilisation regimes

International Nuclear Information System (INIS)

Weih, Martin; Nordh, N.-E.

2002-01-01

Fourteen clones of willow (Salix spp.) were characterised in terms of growth, nitrogen and water-use efficiency under different irrigation and fertilisation treatments. Cuttings of willow clones, some commercially introduced and others new material, were pot-grown outdoors in Central Sweden under four experimental treatments in a full-factorial design. The experiment covered the period from bud-break until leaf abscission and the experimental conditions included two irrigation and two fertilisation regimes. The growth of the clones was evaluated in terms of relative growth rate and total biomass production of whole plants and shoots. Nitrogen (N) economy was studied by means of N productivity, N accumulation and N losses by leaf abscission. Water economy was analysed with respect to intrinsic water-use efficiency (foliar carbon isotope ratio; δ 13 C) and the capacity of leaves to retain water (relative water content). Significant differences between clones were found in nearly all parameters measured and the clones varied in the responses to the experimental treatments (clone x factor interaction effects). Thus, clone ranking often changed depending on the experimental treatment. The results are discussed with respect to clone selection for different willow applications such as biomass production and phytoremediation, and willow growth performance under different water and nutrient availabilities. The growth-physiological characterisation of young willows in the short term (several months) is regarded as a suitable approach for pre-selection of promising clones prior to extensive field evaluation

Small-scale variations of climate change in mountainous forested terrain - a regional study from H.J. Andrews Long Term Ecological Research site in Oregon, USA

Science.gov (United States)

Honzakova, Katerina; Hoffmann, Peter; Jones, Julia; Thomas, Christoph

2017-04-01

There has been conflicting evidence as to whether high elevations are experiencing more pronounced climate warming than lower elevations in mountainous regions. In this study we analyze temperature records from H.J. Andrews Long Term Ecological Research, Oregon, USA and several nearby areas, comprising together 28 stations located in Cascade Mountains. The data, starting in 1958, are first checked for quality and homogenized using the Standard Normal Homogeneity Test. As a reference, composite climate time series based on the Global Historic Climate Network is created and together with cross-referencing against station records used to correct breaks and shifts in the data. In the next step, we investigate temperature patterns of the study site from 1958 to 2016 and compare them for valley and hill stations. In particular, we explore seasonality and inter-annual variability of the records and trends of the last day of frost. Additionally, 'cold' sums (positive and negative) are calculated to obtain a link between temperature and ecosystems' responses (such as budbreaks). So far, valley stations seem to be more prone to climate change than ridge or summit stations, contrary to current thinking. Building on previous knowledge, we attempt to provide physical explanations for the temperature records, focusing on wind patterns and associated phenomena such as cold air drainage and pooling. To aid this we analyze wind speed and direction data available for some of the stations since 1996, including seasonality and inter-annual variability of the observed flows.

Effects of elevated ozone on CO2 uptake and leaf structure in sugar maple under two light environments

International Nuclear Information System (INIS)

Bäck, J.; Vanderklein, D.W.; Topa, M.A.

1999-01-01

The interactive effects of ozone and light on leaf structure, carbon dioxide uptake and short-term carbon allocation of sugar maple (Acer saccharum Marsh.) seedlings were examined using gas exchange measurements and 14 C-macroautoradiographic techniques. Two-year-old sugar maple seedlings were fumigated from budbreak for 5 months with ambient or 3 × ambient ozone in open-top chambers, receiving either 35% (high light) or 15% (low light) of full sunlight. Ozone accelerated leaf senescence, and reduced net photosynthesis, 14 CO 2 uptake and stomatal conductance, with the effects being most pronounced under low light. The proportion of intercellular space increased in leaves of seedlings grown under elevated ozone and low light, possibly enhancing the susceptibility of mesophyll cells to ozone by increasing the cumulative dose per mesophyll cell. Indeed, damage to spongy mesophyll cells in the elevated ozone × low light treatment was especially frequent. 14 C macroautoradioraphy revealed heterogeneous uptake of 14 CO 2 in well defined areole regions, suggesting patchy stomatal behaviour in all treatments. However, in seedlings grown under elevated ozone and low light, the highest 14 CO 2 uptake occurred along larger veins, while interveinal regions exhibited little or no uptake. Although visible symptoms of ozone injury were not apparent in these seedlings, the cellular damage, reduced photosynthetic rates and reduced whole-leaf chlorophyll levels corroborate the visual scaling of whole-plant senescence, suggesting that the ozone × low light treatment accelerated senescence or senescence-like injury in sugar maple. (author)