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Journal articles on the topic 'Tree Growth Phenology'
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1
Schöngart, Jochen, Maria Teresa F. Piedade, Sabine Ludwigshausen, Viviana Horna, and Martin Worbes. "Phenology and stem-growth periodicity of tree species in Amazonian floodplain forests." Journal of Tropical Ecology 18, no. 4 (2002): 581–97. http://dx.doi.org/10.1017/s0266467402002389.
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To study the impact of the annual long-term flooding (flood-pulse) on seasonal tree development in Amazonian floodplains, the phenology and growth in stem diameter of various tree species with different leaf-change patterns were observed over a period of 2 y. The trees of the functional ecotypes, evergreen, brevi-deciduous, deciduous and stem-succulent showed a periodic behaviour mainly triggered by the flood-pulse. Trees have high increment during the terrestrial phase. Flooding causes a shedding of some or all leaves leading to a cambial dormancy of about 2 mo and the formation of an annual ring. Studies carried out in tropical dry forests verify a strong relationship between the phenological development and the water status of the trees, strongly affected by seasonal drought. The comparison of the phenology and the diameter growth of the corresponding ecotypes in floodplain forest and a semi-deciduous forest in Venezuela shows a displacement of at least 2 mo in the periodicity, except for stem-succulent tree species. For stem-succulent trees it remains unclear which factors influence phenology and stem diameter growth.
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Dion, Pierre-Paul, Julie Bussières, and Line Lapointe. "Late canopy closure delays senescence and promotes growth of the spring ephemeral wild leek (Allium tricoccum)." Botany 95, no. 5 (2017): 457–67. http://dx.doi.org/10.1139/cjb-2016-0317.
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Spring ephemerals take advantage of the high light conditions in spring to accumulate carbon reserves through photosynthesis before tree leaves unfold. Recent work has reported delayed leaf senescence under constant light availability in some spring ephemerals, such as wild leek (Allium tricoccum). This paper aims to establish whether tree canopy composition and phenology can influence the growth of spring ephemerals through changes in their phenology. Wild leek bulbs were planted in 31 plots in southern Quebec, Canada, under canopies varying in composition and densities. Light availability and tree phenology were measured, along with other environmental conditions, and their effect on the growth of wild leeks was assessed with a redundancy analysis. Higher light availability resulted in better growth of wild leeks. The plants postponed their senescence under trees with late bud-burst, and thus better bulb growth and seed production were achieved. The tree litter and temperature and moisture levels of the soil also influenced the growth and survival of wild leeks. Thus, tree leaf phenology appears to have a strong impact on the growth of spring ephemerals by modulating the length of their growing season and their photosynthetic capacity. This underlines the importance of considering the variation of light availability throughout the growing season in the study of spring ephemerals.
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Marenco, Ricardo Antonio, Francinete de Freitas Sousa, and Marcilia Freitas de Oliveira. "Leaf phenology, growth and photosynthesis in Pseudobombax munguba (Malvaceae)." Revista Ceres 66, no. 1 (2019): 1–10. http://dx.doi.org/10.1590/0034-737x201966010001.
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ABSTRACT Munguba (Pseudobombax munguba) is a tree often found in low-land forests of the Amazon region, and there is a paucity of data regarding its ecophysiology. The aim of this work was to determine photosynthetic rates and growth of munguba saplings and to describe leaf phenology of a munguba tree. In greenhouse-grown saplings, diameter growth, leaf expansion, photosynthesis and stomatal conductance were determined. To describe the relationship between photosynthesis and leaf expansion, regression analysis was used. It was also described the leaf phenology of an adult tree by observing foliage changes at one-week intervals for two years. The leaves completed their expansion in 18 days, and leaf greening was completed in 40 days. Photosynthesis positively correlated with leaf expansion, but there was no correlation between stomatal conductance and leaf growth. Growth in diameter was 1.8 mm month‒1. Relative growth rate was low, 0.010 g g-1 day-1. In the adult tree, leaf shedding was concentrated in July-August and by the second week of September the tree had already produced new leaves. Leaf longevity of munguba is about 11 months. It is hypothesized that leaf phenology of munguba is associated with the increased solar radiation of the dry season.
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Borchert, Rolf. "Climatic Periodicity, Phenology, and Cambium Activity in Tropical Dry Forest Trees." IAWA Journal 20, no. 3 (1999): 239–47. http://dx.doi.org/10.1163/22941932-90000687.
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The seasonal time course of vegetative phenology and cambium growth is compared for tree species from Central America and Asia growing in tropical climates with a long, severe dry season. Although the inhibition of plant growth by water stress is weH established, responses to seasonal drought vary widely among such trees, and their annual development is not weH synchronized by climatic seasonality. In deciduous trees growing at microsites with low soil moisture storage, phenology and cambium growth are weH correlated with each other and with seasonal rainfall, and most trees have distinct annual rings. Phenology and cambium growth are progressively uncoupled from climatic seasonality in brevideciduous and evergreen trees growing at microsites with large soil water reserves which buffer trees against seasonal drought and thus may prevent the formation of distinct annual rings. There is some experimental evidence conceming the control of growth initiation in apical meristems and the cambium, but little is known about the mechanisms which arrest growth and deterrnine qualitative changes in organ development and cambium cell differentiation.
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Mura, Claudio, Christian Bianchi Strømme, and Tommaso Anfodillo. "Stable Allometric Trajectories in Picea abies (L.) Karst. Trees along an Elevational Gradient." Forests 11, no. 11 (2020): 1231. http://dx.doi.org/10.3390/f11111231.
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The effect of temperature on tree phenology and growth has gained particular attention in relation to climate change. While a number of reports indicate that warming can extend the length of the growing season and enhance tree growth rates, it is still debated whether temperature also affects biomass partitioning. Addressing the question of whether trees grown at different elevations invest similarly in various organs, we established four sites along an elevational gradient (320 to 595 m a.s.l.) in managed Norway spruce (Picea abies (L.) Karts) stands regenerating after clearcuts in central Norway. There, differences in temperature, bud break, tree growth, and allometric scaling were measured in small spruce trees (up to 3 m height). The results showed that bud break and shoot growth are affected by temperature, as lower sites completed the bud break process 5 days earlier than the higher sites did. There was some evidence indicating that the summer drought of 2018 affected tree growth during the season, and the implications of this are discussed. The allometric scaling coefficients did not change for the crown volume (slope value range 2.66–2.84), crown radius (0.77–0.89), and tree diameter (0.89–0.96) against tree height. A slight difference was found in the scaling coefficients of crown length against tree height (slope value range 1.04–1.12), but this did not affect the general scaling of the crown volume with tree height. Our results showed that different local environmental conditions affect both the growth rate and phenology in Norway spruce trees but, on the contrary, that the biomass partitioning among different parts of the tree remains essentially unchanged. This demonstrates that the allometric approach is an important tool for unraveling true vs. apparent plant plasticity, which in turn is an essential awareness for predicting plant responses to environmental changes.
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da Costa, Warlen Silva, Maura Da Cunha, Tahysa Mota Macedo, et al. "Cambium phenology and dendrochronology of the endangered tropical tree Ocotea catharinensis Mez." IAWA Journal 42, no. 2 (2021): 111–20. http://dx.doi.org/10.1163/22941932-bja10023.
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Abstract Ocotea catharinensis occurs mainly in the Brazilian Atlantic Forest and is highly threatened by timber logging, forest fragmentation, and habitat loss. The remnant populations of this species are genetically rich, which may be related to the presence of long-lived trees, and so it is imperative to understand their growth and age. In this study, we analyzed trees of O. catharinensis from dense ombrophylous forest, its dendrochronological potential, the period of cambial activity and dormancy, and the influence of climate on annual growth. The species showed distinct annually-formed tree-rings, with cambial activity during summer and autumn, and cambial dormancy during winter and spring. A tree-ring width chronology was built from 1852–2015. The estimated age of the sampled trees varied from 40 to 164 years. O. catharinensis in our study site does not show a strong age–diameter relationship, hence similar diameters at breast height resulted in differences in ages by as much as 50 years. The resulting tree-ring width chronology is positively correlated with March precipitation, the transition month between rainy and dry seasons. This study brings valuable contributions to the understanding of the growth of O. catharinensis, which is a novelty for this species and important to the maintenance of these long-lived trees in natural forests.
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De Mil, Tom, Wannes Hubau, Bhély Angoboy Ilondea, et al. "Asynchronous leaf and cambial phenology in a tree species of the Congo Basin requires space–time conversion of wood traits." Annals of Botany 124, no. 2 (2019): 245–53. http://dx.doi.org/10.1093/aob/mcz069.
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Abstract Background and Aims Wood traits are increasingly being used to document tree performance. In the Congo Basin, however, weaker seasonality causes asynchrony of wood traits between trees. Here, we monitor growth and phenology data to date the formation of traits. Methods For two seasons, leaf and cambial phenology were monitored on four Terminalia superba trees (Mayombe) using cameras, cambial pinning and dendrometers. Subsequently, vessel lumen and parenchyma fractions as well as high-resolution isotopes (δ13C/δ18O) were quantified on the formed rings. All traits were dated and related to weather data. Key Results We observed between-tree differences in green-up of 45 d, with trees flushing before and after the rainy season. The lag between green-up and onset of xylem formation was 59 ± 21 d. The xylem growing season lasted 159 ± 17 d with between-tree differences of up to 53 d. Synchronized vessel, parenchyma and δ13C profiles were related to each other. Only parenchyma fraction and δ13C were correlated to weather variables, whereas the δ18O pattern showed no trend. Conclusions Asynchrony of leaf and cambial phenology complicates correct interpretation of environmental information recorded in wood. An integrated approach including high-resolution measurements of growth, stable isotopes and anatomical features allows exact dating of the formation of traits. This methodology offers a means to explore the asynchrony of growth in a rainforest and contribute to understanding this aspect of forest resilience.
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Harris, Roger, Nina L. Bassuk, and Thomas H. Whitlow. "A Window Into Below-ground Growth of Landscape Trees: Implications for Transplant Success." HortTechnology 4, no. 4 (1994): 368–71. http://dx.doi.org/10.21273/horttech.4.4.368.
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Root and shoot phenology were observed, and root length within rootballs were calculated for Fraxinus pennsylvanica Marsh. (green ash), Quecus coccinea Muenchh. (scarlet oak), Corylus colurna L. (Turkish hazelnut), and Syringa reticulata (Blume) Hara `Ivory Silk' (tree lilac) trees established in a rhizotron. Easy-to-transplant species (green ash and tree lilac) had more root length within rootballs than difficult-to-transplant species (Turkish hazelnut and scarlet oak). Shoot growth began before root growth on all species except scarlet oak, which began root and shoot growth simultaneously. Fall root growth ceased for all species just after leaf drop. Implications for tree transplanting are discussed.
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De Alvarenga, Allan Maurício Sanches Baptista, Paulo César Botosso, and Patrícia Soffiatti. "Stem growth and phenology of three subtropical mangrove tree species." Brazilian Journal of Botany 40, no. 4 (2017): 907–14. http://dx.doi.org/10.1007/s40415-017-0397-9.
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Richards, Thomas J., Almir Karacic, Rami-Petteri Apuli, Martin Weih, Pär K. Ingvarsson, and Ann Christin Rönnberg-Wästljung. "Quantitative genetic architecture of adaptive phenology traits in the deciduous tree, Populus trichocarpa (Torr. and Gray)." Heredity 125, no. 6 (2020): 449–58. http://dx.doi.org/10.1038/s41437-020-00363-z.
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Abstract In a warming climate, the ability to accurately predict and track shifting environmental conditions will be fundamental for plant survival. Environmental cues define the transitions between growth and dormancy as plants synchronise development with favourable environmental conditions, however these cues are predicted to change under future climate projections which may have profound impacts on tree survival and growth. Here, we use a quantitative genetic approach to estimate the genetic basis of spring and autumn phenology in Populus trichocarpa to determine this species capacity for climate adaptation. We measured bud burst, leaf coloration, and leaf senescence traits across two years (2017–2018) and combine these observations with measures of lifetime growth to determine how genetic correlations between phenology and growth may facilitate or constrain adaptation. Timing of transitions differed between years, although we found strong cross year genetic correlations in all traits, suggesting that genotypes respond in consistent ways to seasonal cues. Spring and autumn phenology were correlated with lifetime growth, where genotypes that burst leaves early and shed them late had the highest lifetime growth. We also identified substantial heritable variation in the timing of all phenological transitions (h2 = 0.5–0.8) and in lifetime growth (h2 = 0.8). The combination of additive variation and favourable genetic correlations in phenology traits suggests that populations of cultivated varieties of P. Trichocarpa may have the capability to adapt their phenology to climatic changes without negative impacts on growth.
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Seiwa, Kenji, and Kihachiro Kikuzawa. "Phenology of tree seedlings in relation to seed size." Canadian Journal of Botany 69, no. 3 (1991): 532–38. http://dx.doi.org/10.1139/b91-072.
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Vertical growth patterns and leaf dynamics of seedlings of 31 deciduous broad-leaved tree species with different seed sizes were examined under either open or shaded conditions. Seed size positively affected initial seedling height and leaf longevity, and negatively affected duration of leaf emergence and leaf-turnover rate. Large-seeded species completed shoot elongation and almost all of their annual leaf production in a short period, irrespective of shading. Small-seeded species attained maximum heights similar to those of large-seeded species under open conditions by having a longer duration of leaf emergence, higher resource allocation to leaf production, and rapid leaf turnover. However, leaf-production and leaf-turnover rates were reduced by shading for small-seeded species, a trait that resulted in lower final seedling heights for small- versus large-seeded species. In small-seeded species, maximum seedling growth was attained only under open conditions through changes in the phenology of leaf dynamics. In contrast, growth of large-seeded species was independent of the effect of light limitation. The importance of seed size in determining seedling establishment success depends on the relationships between seasonal change of environmental light conditions and characteristics of seedling phenology, which are related to seed size. Key words: seed size, tree seedlings, leaf dynamics, phenology, establishment strategies.
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Vitasse, Yann, Sylvain Delzon, Caroline C. Bresson, Richard Michalet, and Antoine Kremer. "Altitudinal differentiation in growth and phenology among populations of temperate-zone tree species growing in a common garden." Canadian Journal of Forest Research 39, no. 7 (2009): 1259–69. http://dx.doi.org/10.1139/x09-054.
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The aim of the study was to determine whether there are genetic variations in growth and leaf phenology (flushing and senescence) among populations of six woody species ( Abies alba Mill., Acer pseudoplatanus L., Fagus sylvatica L., Fraxinus excelsior L., Ilex aquifolium L., and Quercus petraea (Matt.) Liebl.) along altitudinal gradients, using a common-garden experiment. We found (i) significant differences in phenology and growth among provenances for most species and (ii) evidence that these among-population differences in phenology were related to the annual temperature at the provenance sites for ash, beech, and oak. It is noteworthy that along the same climatic gradient, species can exhibit opposing genetic clines: beech populations from high elevations flushed earlier than those from low elevations, whereas we observed the opposite trend for ash and oak. For most species, significant altitudinal clines for growth were also revealed. Finally, we highlighted the fact that both phenology timing and growth rate were highly consistent from year to year. The results demonstrated that despite the proximity of the populations in their natural area, differences in altitude led to genetic differentiation in their phenology and growth. These adaptive capacities acting along a natural climatic gradient could allow populations to cope with current climate change.
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Lisi, Claudio S., Mário Tomazello Fo, Paulo C. Botosso, et al. "Tree-Ring Formation, Radial Increment Periodicity, and Phenology of Tree Species from a Seasonal Semi-Deciduous Forest in Southeast Brazil." IAWA Journal 29, no. 2 (2008): 189–207. http://dx.doi.org/10.1163/22941932-90000179.
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Many tropical tree species produce growth rings in response to seasonal environmental factors that influence the activity of the vascular cambium. We applied the following methods to analyze the annual nature of treering formation of 24 tree species from a seasonal semi-deciduous forest of southeast Brazil: describing wood anatomy and phenology, counting tree rings after cambium markings, and using permanent dendrometer bands. After 7 years of systematic observations and measurements, we found the following: the trees lost their leaves during the dry season and grew new leaves at the end of the same season; trunk increment dynamics corresponded to seasonal changes in precipitation, with higher increment (active period) during the rainy season (October–April) and lower increment (dormant period) during the dry season (May–September); the number of tree rings formed after injuries to the cambium coincided with the number of years since the extraction of the wood samples. As a result of these observations, it was concluded that most study trees formed one growth ring per year. This suggests that tree species from the seasonal semi-deciduous forests of Brazil have an annual cycle of wood formation. Therefore, these trees have potential for use in future studies of tree age and radial growth rates, as well as to infer ecological and regional climatic conditions. These future studies can provide important information for the management and conservation of these endangered forests.
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Mil, Tom De. "Intra-annual to multi-decadal xylem traits in a tropical moist semi-deciduous forest of Central Africa." Afrika Focus 30, no. 1 (2017): 136–40. http://dx.doi.org/10.1163/2031356x-03001010.
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A witness of a tree’s past conditions is the wood itself. The main research question of this dissertation is how to assess and reveal the driving forces of the patterns of wood traits on pith-to-bark cross-sections in tropical trees. Cambial and leaf phenology was monitored in the Luki Reserve (Mayombe forest, D.R. Congo). Furthermore, X-ray CT densitometry was explored to assess traits in a reliable way, for multiple species. Variability in phenology is observed for T. superba, which requires traits of individual trees to be fixed on a time axis. Furthermore, X-ray CT is a suitable method for assessing traits in a fast way. Cambial activity of understory trees has shown to be species-specific, whilst many trees show zero xylem growth. Finally, 66 years of tree growth was analysed, while trait analysis revealed a median ring count of only 32, thus implying many non-periodical rings. This work presents methodological improvements to measure traits as continuous variables from pith to bark, but also acknowledges that phenology still remains a key aspect in order to fix traits on a time axis.
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Gričar, Jožica, Andreja Vedenik, Gregor Skoberne, Polona Hafner, and Peter Prislan. "Timeline of Leaf and Cambial Phenology in Relation to Development of Initial Conduits in Xylem and Phloem in Three Coexisting Sub-Mediterranean Deciduous Tree Species." Forests 11, no. 10 (2020): 1104. http://dx.doi.org/10.3390/f11101104.
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It is unclear how the anticipated climate change will affect the timing of phenology of different tree organs/tissues and thus the whole-tree functioning. We examined the timing of leaf phenology and secondary growth in three coexisting deciduous tree species (Quercus pubescens Willd., Fraxinus ornus L. and Ostrya carpinifolia Scop) from a sub-Mediterranean region in 2019. In addition, we investigated the relationship between leaf and cambial phenology and the onset of the potential functioning of initial conduits, as determined by the completed differentiation process (vessels) or final size (sieve tubes). For this purpose, leaf development was monitored and the microcores of cambium and the youngest phloem and xylem increments were repeatedly collected at 7–10-day intervals during the growing season. The results revealed differences in the timing of leaf development and seasonal radial growth patterns in spring among the studied tree species, depending on wood porosity. We found that cambial cell production started in all cases in the first half of March. However, in ring-porous Q. pubescens and F. ornus, radial growth in the stem occurred more than a month before buds were swollen, whereas in diffuse-porous O. carpinifolia, these two events were detected at almost the same time. The end of cambial cell production occurred earliest in F. ornus (mid-July) and two weeks later also in the other two species. The widest initial earlywood vessels and early phloem sieve tubes were found in Q. pubescens, the narrowest initial earlywood vessels in O. carpinifolia and the narrowest early phloem sieve tubes in F. ornus. This indicates differences in the efficiency of conducting systems among the studied species. This novel approach of studying phloem phenology and anatomy in relation to leaf and xylem development contributes to a better understanding of how different tree species adapt their structure of secondary vascular tissues in response to environmental change.
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Host, George E., Harlan W. Stech, Kathryn E. Lenz, Kyle Roskoski, and Richard Mather. "Forest patch modeling: using high performance computing to simulate aboveground interactions among individual trees." Functional Plant Biology 35, no. 10 (2008): 976. http://dx.doi.org/10.1071/fp08075.
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Functional–structural plant models (FSPMs) typically integrate suites of detailed physiological and phenological processes to simulate the growth of individual plants. Recent advances in high-performance computing have allowed FSPMs to be extended to patches of interacting trees. Here, we describe a parallel modelling strategy to run simultaneous individual tree models across an 8 × 8 patch of trees. The 64 ‘core’ trees are surrounded by multiple rings of neighbour trees to remove edge effects. A sensitivity analysis of the patch model demonstrates that computational factors such as the number of independently simulated trees (9 v. 36) or number of neighbour rings (3 v. 6) did not significantly influence model estimates of tree volume growth. Updated submodels for phenology and redistribution of overwinter carbohydrate storage allow the simulation to be more responsive to above ground competition among trees in a patch over multiple growing seasons. An 8-year patch-scale simulation of aspen clones 216 and 259 was conducted using high-resolution environmental data from the Aspen FACE Experiment, a long-term free-air carbon dioxide enrichment (FACE) study. Tree heights and volumes were comparable to 8-year growth measurements made at the Aspen FACE site.
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Chilcote, Charley A., John A. Witter, Michael E. Montgomery, and Jennifer L. Stoyenoff. "Intra- and inter-clonal variation in gypsy moth larval performance on bigtooth and trembling aspen." Canadian Journal of Forest Research 22, no. 11 (1992): 1676–83. http://dx.doi.org/10.1139/x92-221.
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A field study on the effects of interclonal and intraclonal variations of aspens on the performance of gypsy moth, Lymantriadispar (L.), was conducted in Michigan during 1988 and 1989. Study species were trembling aspen, Populustremuloides Michx., and bigtooth aspen, Populusgrandidentata Michx. Larvae were caged on intact host trees in the field in fine mesh bags. We examined the leaf phenological development of aspen clones and its relationship to a number of insect parameters: larval weight, relative growth rates, survival, and pupal weights. Interclonal variations in larval growth on trembling aspen clones and bigtooth aspen clones were high in 1988 and 1989. Leaf phenological differences between clones also were highly significant. These differences in leaf phenology led to a window of vulnerability existing for each clone. While insects that initiated feeding on phenologically delayed clones had poorer survival and lower growth rates than did larvae on more phenologically advanced clones, later in the season these larvae were able to catch up as the phenology of delayed clones caught up to that of more advanced clones. Because of this, pupal weights did not show significant effects of clones. Intraclonal variation in larval growth was extremely low for all growth periods. While there were significant differences in phenology between ramets within clones, the variation was much less than the variation seen in phenological differences between clones. Phenology of caged branches within a tree did not vary significantly for either species.
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Stanley, Celina H., Carola Helletsgruber, and Angela Hof. "Mutual Influences of Urban Microclimate and Urban Trees: An Investigation of Phenology and Cooling Capacity." Forests 10, no. 7 (2019): 533. http://dx.doi.org/10.3390/f10070533.
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This paper presents an empirical study on urban tree growth and regulating ecosystem services along an urban heat island (UHI) intensity gradient. The UHI effect on the length of the growing season and the association of cooling and shading with species, age, and size of trees was studied in Salzburg, Austria. Results show that areas with a low UHI intensity differed from areas with a medium or high UHI intensity significantly in three points: their bud break began later, the leaf discoloration took longer, and the growing season was shorter. After leaves have developed, trees cool the surface throughout the whole growing season by casting shadows. On average, the surfaces in the crown shade were 12.2 °C cooler than those in the sun. The tree characteristics had different effects on the cooling performance. In addition to tree height and trunk circumference, age was especially closely related to surface cooling. If a tree’s cooling capacity is to be estimated, tree age is the most suitable measure, also with respect to its assessment effort. Practitioners are advised to consider the different UHI intensities when maintaining or enhancing public greenery. The cooling capacity of tall, old trees is needed especially in areas with a high UHI intensity. In the future, species differences should be examined to determine the best adapted species for the different UHI intensities. The present results can be the basis for modeling future mutual influences of microclimate and urban trees.
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Zhang, Wangfei, Yongxin Zhang, Yue Yang, and Erxue Chen. "Oilseed Rape (Brassica napus L.) Phenology Estimation by Averaged Stokes-Related Parameters." Remote Sensing 13, no. 14 (2021): 2652. http://dx.doi.org/10.3390/rs13142652.
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Accurate and timely knowledge of crop phenology assists in planning and/or triggering appropriate farming activities. The multiple Polarimetric Synthetic Aperture Radar (PolSAR) technique shows great potential in crop phenology retrieval for its characterizations, such as short revisit time, all-weather monitoring and sensitivity to vegetation structure. This study aims to explore the potential of averaged Stokes-related parameters derived from multiple PolSAR data in oilseed rape phenology identification. In this study, the averaged Stokes-related parameters were first computed by two different wave polarimetric states. Then, the two groups of averaged Stokes-related parameters were generated and applied for analyzing averaged Stokes-related parameter sensitivity to oilseed rape phenology changes. At last, decision tree (DT) algorithms trained using 60% of the data were used for oilseed rape phenological stage classification. Four Stokes parameters (g0, g1, g2 and g3) and eight sub parameters (degree of polarization m, entropy H, ellipticity angle χ, orientation angle φ, degree of linear polarization Dolp, degree of circular polarization Docp, linear polarization ratio Lpr and circular polarization ratio Cpr) were extracted from a multi-temporal RADARSAT-2 dataset acquired during the whole oilseed rape growth cycle in 2013. Their sensitivities to oilseed rape phenology were analyzed versus five main rape phenology stages. In two groups (two different wave polarimetric states) of this study, g0, g1, g2, g3, m, H, Dolp and Lpr showed high sensitivity to oilseed rape growth stages while χ, φ, Docp and Cpr showed good performance for phenology classification in previous studies, which were quite noisy during the whole oilseed rape growth circle and showed unobvious sensitivity to the crop’s phenology change. The DT algorithms performed well in oilseed rape phenological stage identification. The results were verified at the parcel level with left 40% of the point dataset. Five phenology intervals of oilseed rape were identified with no more than three parameters by simple but robust decision tree algorithm groups. The identified phenology stages agree well with the ground measurements; the overall identification accuracies were 71.18% and 79.71%, respectively. For each growth stage, the best performance occurred at stage S1 with the accuracy of 95.65% for Group 1 and 94.23% for Group 2, and the worst performance occurred at stage S3 and S5 with the values around 60%. Most of the classification errors may resulted from the indistinguishability of S3 and S5 using Stokes-related parameters.
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Dox, Inge, Jožica Gričar, Lorène J. Marchand, et al. "Timeline of autumn phenology in temperate deciduous trees." Tree Physiology 40, no. 8 (2020): 1001–13. http://dx.doi.org/10.1093/treephys/tpaa058.
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Abstract Cessation of xylem formation or wood growth (CWG) and onset of foliar senescence (OFS) are key autumn phenological events in temperate deciduous trees. Their timing is fundamental for the development and survival of trees, ecosystem nutrient cycling and the seasonal exchange of matter and energy between the biosphere and atmosphere, and affects the impact and feedback of forests to global change. A large-scale experimental effort and improved observational methods have allowed us to compare the timing of CWG and OFS for different deciduous tree species in Western Europe, particularly in silver birch, a pioneer species, and European beech, a late-succession species, at stands of different latitudes, of different levels of site fertility, for 2 years with contrasting meteorological and drought conditions, i.e., the low moderately dry 2017 and the extremely dry 2018. Specifically, we tested whether foliar senescence started before, after or concurrently with CWG. Onset of foliar senescence and CWG occurred generally between late September and early November, with larger differences across species and sites for OFS. Foliar senescence started concurrently with CWG in most cases, except for the drier 2018 and, for beech, at the coldest site, where OFS occurred significantly later than CWG. The behavior of beech in Spain, the southern edge of its European distribution, was unclear, with no CWG, but very low wood growth at the time of OFS. Our study suggests that OFS is generally triggered by the same drivers of CWG or when wood growth decreases in late summer, indicating an overarching mechanism of sink limitation as a possible regulator of the timing of foliar senescence.
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Pérez-Romero, L. F., F. T. Arroyo, C. Santamaría, J. F. Herencia, and A. Daza. "Growth, phenology and fruit set of Prunus armeniaca L. (cv. Ninfa) grafted on two rootstocks in organic and conventional management." Horticultural Science 41, No. 3 (2014): 101–6. http://dx.doi.org/10.17221/46/2014-hortsci.
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Tree growth, flowering, yield and fruit quality of Prunus armeniaca L. cv. Ninfa grafted on peach cv. Nemaguard [Prunus persica (L.) Batsch] and cv. Real Fino apricot (Prunus armeniaca L.) as rootstocks were analysed in experimental orchard under organic and conventional management systems. The study was performed during 2012–2013 in the province of Seville (SW Spain). Cv. Nemaguard rootstock had larger cross-sectional areas of the trunk (TCSA), higher yields, began flowering earlier and lasted 2–4 days more. The organic management resulted in lower values of TCSA and yield, and flowering was delayed and shortened. Overall, cv. Nemaguard rootstock produced slightly larger fruit in size and heavier weight. In contrast, apricots from cv. Real Fino had slightly higher soluble solid concentration. Acidity and maturity index were similar, while colour and firmness showed high variability. In general, the organic system produced fruit with soluble solid concentration somewhat higher. In summary, in both types of management cv. Nemaguard worked better than cv. Real Fino in terms of tree vigour, fruit yield and bloom period.    
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Kilpeläinen, Jouni, Timo Domisch, Tarja Lehto, et al. "Root and shoot phenology and root longevity of Norway spruce saplings grown at different soil temperatures." Canadian Journal of Forest Research 49, no. 11 (2019): 1441–52. http://dx.doi.org/10.1139/cjfr-2019-0190.
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Tree roots comprise a huge carbon pool. Their dynamics are driven by environmental factors and thereby affected by climate change. We studied the effects of soil temperature on root and shoot phenology and their linkages in Norway spruce (Picea abies (L.) Karst.). Saplings were grown in controlled-environment rooms for three simulated growing seasons (GS1, GS2, and GS3). Soil-temperature treatments of 9, 13, 18, and 21 °C were applied during GS2. Root growth was monitored with minirhizotrons and commenced in all treatments simultaneously. Temporal growth patterns of short and long roots were usually bimodal. Root growth was very low during the coldest treatment of GS2 but increased during GS3 as an aftereffect. During GS3, growth of short roots continued later after colder treatments than warmer treatments. Reduced sink strength of roots and increased carbohydrate accumulation into needles at 9 °C during GS2 probably enabled compensatory root growth under restored temperatures during GS3. Soil temperature did not affect shoot phenology, and root and shoot phenology varied between growing seasons; thus, the linkage of root and shoot phenology was inconsistent. In warmer soil, root longevity was shorter and turnover rate was higher than in colder soil. This can further affect soil carbon dynamics and ecosystem carbon cycling in boreal forest ecosystems.
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Malik, Rayees, Sergio Rossi, and Raman Sukumar. "Cambial phenology in Abies pindrow (Pinaceae) along an altitudinal gradient in northwestern Himalaya." IAWA Journal 41, no. 2 (2020): 186–201. http://dx.doi.org/10.1163/22941932-bja10007.
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Abstract Climate change is expected to be heterogeneous across the world, with high impacts on the Himalayan ecosystems. There is a need to precisely document cambial phenology and wood formation in these regions to better understand climate-growth relationships and how trees face a warming climate. This study describes the dynamics of cambial phenology in pindrow fir (Abies pindrow) along its altitudinal gradient in the Himalaya. The stages of xylem phenology, and the duration and rate of wood formation were assessed from anatomical observations during the growing season from samples collected weekly from three sites at various altitudes (2392–2965 m a.s.l.) over two years. There were significant differences in the duration and rate of cell formation along the altitudinal gradient, which decreased at increasing altitudes. The growing season duration decreased by 5.2 and 3.7 days every 100 m of increase in altitude in 2014 and 2015, respectively, while the rate of cell formation decreased from 0.38 and 0.44 cells /day to 0.29 and 0.34 cells/day in 2014 and 2015, respectively. Cell production decreased from 63.3 and 67.0 cells to 38.3 and 45.2 cells with a decrease of 4.3 and 3.8 cells per 100 m increase in altitude in 2014 and 2015, respectively. The higher precipitation in 2015 increased the growth rate and resulted in a higher xylem production. Our findings give new insights into the dynamics of cambial phenology and help in better understanding of the potential impacts of climate change on tree growth and forest productivity of Himalayan forests.
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Yang, Bao, Minhui He, Vladimir Shishov, et al. "New perspective on spring vegetation phenology and global climate change based on Tibetan Plateau tree-ring data." Proceedings of the National Academy of Sciences 114, no. 27 (2017): 6966–71. http://dx.doi.org/10.1073/pnas.1616608114.
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Phenological responses of vegetation to climate, in particular to the ongoing warming trend, have received much attention. However, divergent results from the analyses of remote sensing data have been obtained for the Tibetan Plateau (TP), the world’s largest high-elevation region. This study provides a perspective on vegetation phenology shifts during 1960–2014, gained using an innovative approach based on a well-validated, process-based, tree-ring growth model that is independent of temporal changes in technical properties and image quality of remote sensing products. Twenty composite site chronologies were analyzed, comprising about 3,000 trees from forested areas across the TP. We found that the start of the growing season (SOS) has advanced, on average, by 0.28 d/y over the period 1960–2014. The end of the growing season (EOS) has been delayed, by an estimated 0.33 d/y during 1982–2014. No significant changes in SOS or EOS were observed during 1960–1981. April–June and August–September minimum temperatures are the main climatic drivers for SOS and EOS, respectively. An increase of 1 °C in April–June minimum temperature shifted the dates of xylem phenology by 6 to 7 d, lengthening the period of tree-ring formation. This study extends the chronology of TP phenology farther back in time and reconciles the disparate views on SOS derived from remote sensing data. Scaling up this analysis may improve understanding of climate change effects and related phenological and plant productivity on a global scale.
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Haverd, V., B. Smith, M. Raupach, et al. "Coupling carbon allocation with leaf and root phenology predicts tree–grass partitioning along a savanna rainfall gradient." Biogeosciences 13, no. 3 (2016): 761–79. http://dx.doi.org/10.5194/bg-13-761-2016.
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Abstract. The relative complexity of the mechanisms underlying savanna ecosystem dynamics, in comparison to other biomes such as temperate and tropical forests, challenges the representation of such dynamics in ecosystem and Earth system models. A realistic representation of processes governing carbon allocation and phenology for the two defining elements of savanna vegetation (namely trees and grasses) may be a key to understanding variations in tree–grass partitioning in time and space across the savanna biome worldwide. Here we present a new approach for modelling coupled phenology and carbon allocation, applied to competing tree and grass plant functional types. The approach accounts for a temporal shift between assimilation and growth, mediated by a labile carbohydrate store. This is combined with a method to maximize long-term net primary production (NPP) by optimally partitioning plant growth between fine roots and (leaves + stem). The computational efficiency of the analytic method used here allows it to be uniquely and readily applied at regional scale, as required, for example, within the framework of a global biogeochemical model.We demonstrate the approach by encoding it in a new simple carbon–water cycle model that we call HAVANA (Hydrology and Vegetation-dynamics Algorithm for Northern Australia), coupled to the existing POP (Population Orders Physiology) model for tree demography and disturbance-mediated heterogeneity. HAVANA-POP is calibrated using monthly remotely sensed fraction of absorbed photosynthetically active radiation (fPAR) and eddy-covariance-based estimates of carbon and water fluxes at five tower sites along the North Australian Tropical Transect (NATT), which is characterized by large gradients in rainfall and wildfire disturbance. The calibrated model replicates observed gradients of fPAR, tree leaf area index, basal area, and foliage projective cover along the NATT. The model behaviour emerges from complex feedbacks between the plant physiology and vegetation dynamics, mediated by shifting above- versus below-ground resources, and not from imposed hypotheses about the controls on tree–grass co-existence. Results support the hypothesis that resource limitation is a stronger determinant of tree cover than disturbance in Australian savannas.
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Haverd, V., B. Smith, M. Raupach, et al. "Coupling carbon allocation with leaf and root phenology predicts tree-grass partitioning along a savanna rainfall gradient." Biogeosciences Discussions 12, no. 19 (2015): 16313–57. http://dx.doi.org/10.5194/bgd-12-16313-2015.
Full textAbstract:
Abstract. The relative complexity of the mechanisms underlying savanna ecosystem dynamics, in comparison to other biomes such as temperate and tropical forests, challenges the representation of such dynamics in ecosystem and Earth system models. A realistic representation of processes governing carbon allocation and phenology for the two defining elements of savanna vegetation (namely trees and grasses) may be a key to understanding variations in tree/grass partitioning in time and space across the savanna biome worldwide. Here we present a new approach for modelling coupled phenology and carbon allocation, applied to competing tree and grass plant functional types. The approach accounts for a temporal shift between assimilation and growth, mediated by a labile carbohydrate store. This is combined with a method to maximise long-term net primary production (NPP) by optimally partitioning plant growth between fine roots and (leaves + stem). The computational efficiency of the analytic method used here allows it to be uniquely and readily applied at regional scale, as required, for example, within the framework of a global biogeochemical model. We demonstrate the approach by encoding it in a new simple carbon/water cycle model that we call HAVANA (Hydrology and Vegetation-dynamics Algorithm for Northern Australia), coupled to the existing POP (Population Orders Physiology) model for tree demography and disturbance-mediated heterogeneity. HAVANA-POP is calibrated using monthly remotely-sensed fraction of absorbed photosynthetically active radiation (fPAR) and eddy-covariance-based estimates of carbon and water fluxes at 5 tower sites along the Northern Australian Tropical Transect (NATT), which is characterized by large gradients in rainfall and wildfire disturbance. The calibrated model replicates observed gradients of fPAR, tree leaf area index, basal area and foliage projective cover along the NATT. The model behaviour emerges from complex feed-backs between the plant physiology and vegetation dynamics, mediated by shifting above- vs. below-ground resources, and not from imposed hypotheses about the controls on tree/grass co-existence. Results support the hypothesis that resource limitation is a stronger determinant of tree cover than disturbance in Australian savannas.
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Yuri, Jose A., Claudia Moggia, Carolina A. Torres, Alvaro Sepulveda, Valeria Lepe, and Jose L. Vasquez. "Performance of Apple (Malus ×domestica Borkh.) Cultivars Grown in Different Chilean Regions on a Six-year Trial, Part I: Vegetative Growth, Yield, and Phenology." HortScience 46, no. 3 (2011): 365–70. http://dx.doi.org/10.21273/hortsci.46.3.365.
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Performance of seven apple (Malus ×domestica Borkh.) cultivars (‘Brookfield®Gala’, ‘Galaxy’, ‘Super Chief’, ‘Granny Smith’, ‘Fuji Raku Raku’, ‘Cripp's Pink’, and ‘Braeburn’) on M.M.106 and M.9 EMLA rootstocks during their first 6 years was evaluated on a multisite trial in Chile. Second-leaf trees were planted in experimental blocks inside commercial orchards located in five major apple-producing areas in Chile (Graneros, San Clemente, Chillan, Angol, and Temuco). Tree height and volume, trunk cross-sectional area (TCA), fruit yield and size distribution, crop load, and tree phenology were assessed annually. In general, tree growth rates by the end of the third year, when they reached the desired height, were similar in all block locations. M.9 EMLA rootstock reduced tree height by ≈20% in ‘Brookfield® Gala’, ‘Fuji’, ‘Galaxy’, and ‘Granny Smith’. This rootstock also had 50% smaller TCAs than M.M.106’s at Year 6 in most cultivars. The highest productions in ‘Brookfield®Gala’, ‘Galaxy’, ‘Granny Smith’, ‘Cripp's Pink’, and ‘Super Chief’, regardless of rootstock, were obtained in San Clemente and Chillan's blocks. Although M.M. 106 trees delivered higher yields per plant, M.9 EMLA yield efficiency (no. fruit/cm2 TCA) was significantly higher. In general, the higher the latitude (toward south), the later budbreak, full bloom, and harvest occurred.
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Doherty, Jean-François, Jean-Frédéric Guay, and Conrad Cloutier. "Temperature-manipulated dynamics and phenology ofMindarus abietinus(Hemiptera: Aphididae) in commercial Christmas tree plantations in Québec, Canada." Canadian Entomologist 149, no. 6 (2017): 801–12. http://dx.doi.org/10.4039/tce.2017.41.
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AbstractThe balsam twig aphidMindarus abietinusKoch (Hemiptera: Aphididae) is a major pest of economic importance for the Christmas tree industry. Global warming during the 21st century could potentially increase local population densities and reinforce the pest status of this aphid in commercial fir (AbiesMiller; Pinaceae) plantations in Québec, Canada. During this study, we tested the effects of a warmer environment on colony growth rates ofM. abietinusand aphid morph composition during the second generation of its cycle, which is key to colony size growth and potential damage to Christmas trees. We monitoredM. abietinuspopulations on two host fir species and one host fir variety, in order to understand the early season dynamics of this aphid and its host tree. It was possible to distinguish the two overlapping generations of winged aphids leaving colonies, which led to observing a much higher proportion of wingless daughters, produced by the stem mother, than what had previously been reported. Colony growth rates were significantly higher in a warmer environment than in the nearby plantation, suggesting that warmer temperatures in late spring and early summer may provide the suitable conditions required forM. abietinuscolonies of greater density.
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Stratópoulos, Zhang, Häberle, et al. "Effects of Drought on the Phenology, Growth, and Morphological Development of Three Urban Tree Species and Cultivars." Sustainability 11, no. 18 (2019): 5117. http://dx.doi.org/10.3390/su11185117.
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: Under changing climatic conditions, drought may become a critical constraint for trees in urban areas, particularly at roadsides and highly paved squares. As healthy urban trees have proven to be an important mitigation and adaptation tool for climate change as well as a significant provider of ecosystem services, there is a need for planting species and cultivars capable of coping with the limited water supply. However, data on species’ and cultivars’ response to drought, particularly their water supplying root systems remains rare. To consider the whole plant responses to drought situations, we studied the growth and phenology of three frequently planted tree species and cultivars with a diameter of 5–6 cm during a one-year rainfall exclusion experiment conducted in a nursery field as well as the dry biomass of the compartments branch, stem, and root after excavation. Our results revealed that species’ and cultivars’ performance were linked to their within-plant carbon partitioning. A high tolerance to drought was noted for Acer campestre, with a particularly high ratio of root:shoot ratio, which made it presumably less susceptible to droughts. Tilia cordata ‘Greenspire’ was highly affected by the reduced water availability visible through prematurely leaf senescence, while Carpinus betulus ‘Fastigiata’ suffered from losing a considerable part of its root biomass, which resulted in the lowest root:shoot ratio of all species and cultivars. This study demonstrated the need for investigating the reaction patterns of species and cultivars by considering both the above-and the below-ground plant parts. We recommend that, for future tree plantings at harsh and challenging urban sites, an important selection criterion should be species’ and cultivars’ capability to develop and retain strong and dense root systems even under limited water supply, as that is believed to be an important trait for drought tolerance.
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Davenport, Thomas L. "658 Processes Influencing Floral Initiation and Bloom: The Role of Phytohormones in a Conceptual Flowering Model." HortScience 34, no. 3 (1999): 561D—561. http://dx.doi.org/10.21273/hortsci.34.3.561d.
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The reproductive phenology of temperate tree fruit species, such as apple and peach, will be briefly introduced and compared to the reproductive phenologies of several tropical and subtropical tree fruit species. Conceptual models of citrus and mango flowering will be described which help to understand the physiological mechanisms of flowering and vegetative flushes in trees growing in subtropical and tropical environments. Possible roles for auxin and cytokinins in shoot initiation and for gibberellins and a putative florigenic promoter in induction will be discussed as they relate to the physiology of flowering and vegetative flushes of tropical species. Successful application of these conceptual flowering models in controlling flowering of citrus, mango, lychee, and longan through the use of growth regulators and other horticultural management techniques will be described.
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Balduman, L. M., S. N. Aitken, M. Harmon, and W. T. Adams. "Genetic variation in cold hardiness of Douglas-fir in relation to parent tree environment." Canadian Journal of Forest Research 29, no. 1 (1999): 62–72. http://dx.doi.org/10.1139/x98-180.
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The extent to which parent trees within breeding zones of coastal Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) are locally adapted to their native environments was evaluated. Forty families from each of one Coastal and one Cascade breeding population in Oregon were assessed for cold hardiness and growth phenology, and family means for traits were summarized using principal components analysis (PCA). Composition of the first two principal components (PCs) was consistent between breeding zones, years, and test sites. PC-1, describing 39-46% of trait variation, represents a suite of traits related to spring phenology and spring cold hardiness. PC-2, describing 20-22% of trait variation, consists of cold-hardiness traits not associated with phenology. The first two PCs from each population, as well as univariate traits, were regressed on parent tree location variables and modeled climatic indices separately. In the Coastal zone, PC-1 was weakly but significantly related to temperature and moisture regimes (0.176 [Formula: see text] r2 [Formula: see text] 0.235), varying with elevation and distance from the ocean. PC-2 was related to temperature and moisture regimes in both populations (0.087 [Formula: see text] r2 [Formula: see text] 0.249). These relatively weak geographic patterns for adaptive traits within breeding zones suggest that current zone size is not excessive and could likely be increased north or south.
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Campisi-Pinto, Salvatore, Yusheng Zheng, Philippe E. Rolshausen, et al. "Optimal Nutrient Concentration Ranges of ‘Hass’ Avocado Cauliflower Stage Inflorescences—Potential Diagnostic Tool to Optimize Tree Nutrient Status and Increase Yield." HortScience 52, no. 12 (2017): 1707–15. http://dx.doi.org/10.21273/hortsci12437-17.
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Optimizing ‘Hass’ avocado (Persea americana Mill.) tree nutrient status is essential for maximizing productivity. Leaf nutrient analysis is used to guide avocado fertilization to maintain tree nutrition. The goal of this research was to identify a ‘Hass’ avocado tissue with nutrient concentrations predictive of yields greater than 40 kg of fruit per tree. This threshold was specified to assist the California avocado industry to increase yields to ≈11,200 kg·ha−1. Nutrient concentrations of cauliflower stage inflorescences (CSI) collected in March proved better predictors of yield than inflorescences collected at full bloom (FBI) in April, fruit pedicels (FP) collected at five different stages of avocado tree phenology from the end of fruit set in June through April the following spring when mature fruit enter a second period of exponential growth, or 6-month-old spring flush leaves (LF) from nonbearing vegetative shoots collected in September (California avocado industry standard). For CSI tissue, concentrations of seven nutrients, nitrogen (N), phosphorus (P), potassium (K), magnesium (Mg), sulfur (S), zinc (Zn), and copper (Cu) were predictive of trees producing greater than 40 kg of fruit annually. Conditional quantile sampling and frequency analysis were used to identify optimum nutrient concentration ranges (ONCR) for each nutrient. Optimum ratios between nutrient concentrations and yields greater than 40 kg per tree were also derived. The high nutrient concentrations characterizing CSI tissue suggest current fertilization practices (timing or amounts) might be causing nutrient imbalances at this stage of avocado tree phenology that are limiting productivity, a possibility that warrants further investigation. Because CSI samples can be collected 4–6 weeks before full bloom, nutritional problems can be addressed before they affect flower retention and fruit set to increase current crop yield, fruit size, and quality. Thus, CSI nutrient analysis warrants further research as a potential supplemental or alternative tool for diagnosing ‘Hass’ avocado tree nutrient status and increasing yield.
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Nerd, Avinoam, Vered Irijimovich, and Yosef Mizrahi. "Phenology, Breeding System, and Fruit Development of Cultivated Argan [Argania spinosa (L.) Skeels]." HortScience 32, no. 3 (1997): 474E—474. http://dx.doi.org/10.21273/hortsci.32.3.474e.
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Argan is a wild tree native to southwestern Morocco, appreciated for its edible, high nutritional oil, extracted from the kernels of the drupe-like fruit. Aspects of its reproductive biology were studied with the aim to domesticate argan as an oil crop. Flowering of fertigated trees cultivated in the Negev Highlands of Israel was confined to the spring months. The flowers were found to be protogynous, the stigma protruding from the flower before anthesis. Stigma receptivity at the pre-anthesis phase was a third of that at anthesis. Results of different pollination treatments showed that a pollen vector was necessary for pollination and that fruit set was significantly higher in cross and open pollination (7% to 9%) than in self pollination (0.5%). Since in-vivo pollen germination and pollen tube growth in the pistil were similar for foreign and self pollen, the lower fruit set obtained in self pollination may have been related to postzygotic discrimination. Pollen transfer by wind was restricted to short distances, and flies (family Calliphoridae), were proven to be involved in pollination. In contrast with stands in argan's native habitat, where fruit growth is inhibited in summer, fruits of the cultivated trees grew continuously throughout the summer. The pattern of growth of fruit fresh weight was similar to that shown for typical fleshy drupaceous fruits, with an initial and a final phase of rapid growth interrupted by a phase of slow growth.
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Danner, Moeses Andrigo, Idemir Citadin, Simone Aparecida Zolet Sasso, Marcos Robson Sachet, and Sérgio Miguel Mazaro. "Germplasm characterization of three jabuticaba tree species." Revista Brasileira de Fruticultura 33, no. 3 (2011): 839–47. http://dx.doi.org/10.1590/s0100-29452011005000095.
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The purpose of this study was to characterize cultivated genotypes of three jabuticaba species (Plinia cauliflora, P. trunciflora, and P. jaboticaba). Phenology and fruit growth, as well as leaf, flower and fruit traits were evaluated. Variability in all traits was observed among genotypes of the three jabuticaba species. The trait peduncle size is indicated for differentiation of the three species under study. The leaf and fruit sizes of the genotypes P. trunciflora 3, P. trunciflora 4, P. trunciflora 5 and P. jaboticaba 1 differ from those described in the literature for these species, indicating the formation of ecotypes. Jabuticaba fruit skin contains high anthocyanin and flavonoid concentrations, with potential use in food and pharmaceutical industries.
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Silva, Marlon Jocimar Rodrigues da, Marco Antonio Tecchio, Sofia Domiciano, Sarita Leonel, and Rodrigo Issa Balestrero. "Phenology, yield and fruit quality of 'Paluma' guava tree at different pruning times." Ciência e Agrotecnologia 40, no. 3 (2016): 317–25. http://dx.doi.org/10.1590/1413-70542016403033315.
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ABSTRACT Pruning guava trees at different times is an important management tool that allows year-long staggering of fruit production. In this context, this study aimed to evaluate the phenological characteristics, yield and fruit quality of the 'Paluma' guava tree at different pruning times in Botucatu, SP. The study used a completely randomized design with four treatments, four replicates and a useful experimental plot plant. The treatments consisted of four different pruning times, August 27, September 11, September 26 and October 11. The following phenological phases were evaluated: branch establishment, flowering, early fruiting, fruit ripening and harvesting. It was determined the number of flower buds, fixed fruits and fixation index fruit were determined. The fruit growth curve was obtained by measuring the transverse and longitudinal diameter. At the time of harvest, the number of fruits per plant, yield and productivity were measured. In the harvested fruits, the fresh mass, the transverse and longitudinal diameter, the flesh and core thickness, the flesh and core mass, soluble solids, titratable acidity and pH were determined. The 'Paluma' guava trees pruned in August showed higher phenological stage durations than the other pruning times; however, those pruned in early September showed higher fixation index fruit, fruit yield and better physical characteristics. The guava trees pruned in August showed lower titratable acidity values and higher soluble solids/titratable acidity ratio.
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Callado, Cátia Henriques, Sebastião José da Silva Neto, Fábio Rubio Scarano, and Cecília Gonçalves Costa. "RADIAL GROWTH DYNAMICS OF TABEBUIA UMBELLATA (BIGNONIACEAE), A FLOOD-TOLERANT TREE FROM THE ATLANTIC FOREST SWAMPS IN BRAZIL." IAWA Journal 25, no. 2 (2004): 175–83. http://dx.doi.org/10.1163/22941932-90000359.
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We studied the annual radial growth of Tabebuia umbellata (Sond.) Sandwith (Bignoniaceae) and its relationship to rainfall, temperature, photoperiod, flooding and phenology. This species showed cyclic annual growth. Growth was the greatest during the rainy season and flooding. Growth was associated with the presence of mature leaves on the trees. No increase in girth was observed during the dry season or during defoliation or flowering. The mean rate of radial growth was c. 6 mm/year. This flood-tolerant species maintained and increased radial growth during flooding.
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Girard, Marie-Josée, Sergio Rossi, and Hubert Morin. "MAPPING EVENTS: CAMBIUM PHENOLOGY ACROSS THE LATITUDINAL DISTRIBUTION OF BLACK SPRUCE." IAWA Journal 36, no. 3 (2015): 270–85. http://dx.doi.org/10.1163/22941932-20150091.
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This study used statistical models for describing the spatial patterns of variation in cambium phenology and xylem cell production across the entire latitudinal distribution of a species. The studied area extends over 600 km from the 48th to the 53rd parallel in the boreal forest of Quebec, Canada. Microcores were collected weekly from April to October 2012 from 50 Black spruce [Picea mariana (Mill.) BSP] trees in five stands. The dates of occurrence of the phases of cambium phenology were identified on histological sections and correlated to the latitude and altitude of the sites by means of linear and non-linear functions. The results were used to estimate the timings of xylem growth and cell production across the sampled region. Phenology was mostly represented by linear functions. The increase in latitude and altitude produced a proportional variation in the beginning and ending of xylem differentiation, thus leading to a shorter length of the period of wood formation. The phase of cell enlargement and cell production changed according to a non-linear pattern represented by a negative exponential curve. Latitude was the factor with the greatest impact on xylem phenology, while altitude had a slight or no effect, especially for nonlinear relationships. Xylem formation is a complex process composed of several phenological phases that change across a species distribution area according to either linear or non-linear patterns. Knowledge and quantification of these patterns are important for modelling the dynamics of tree growth across wide geographical areas and for predicting productivity of forest ecosystems under climate change scenarios.
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Orduz-Rodríguez, Javier Orlando, and Diana Lucia Garzón C. "Alternancia de la producción y comportamiento fenológico de la naranja ‘Valencia’ (Citrus sinensis [L.] Osbeck) en el trópico bajo húmedo de Colombia." Corpoica Ciencia y Tecnología Agropecuaria 13, no. 2 (2013): 136. http://dx.doi.org/10.21930/rcta.vol13_num2_art:248.
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<p>En condiciones tropicales cerca de la línea ecuatorial, la precipitación es el principal factor climático que influye sobre el crecimiento y desarrollo de las plantas de cítricos. En un cultivo de naranja ‘Valencia’ de 11 años de edad ubicado en suelos de la terraza alta del piedemonte llanero en Corpoica, Centro de Investigación La Libertad, en Villavicencio, Meta, Colombia, se llevaron los registros de producción por árbol en los años 2008 a 2010. A diez árboles marcados se le tomó información quincenal de la fenología de la planta en los cuatro puntos cardinales utilizando la metodología de Garrán <em>et al</em>. (1993) durante los años 2009 y 2010. Para estos mismos años se calculó el balance hídrico para el cultivo. La información se analizó con estadística descriptiva para la mayoría de las variables, prueba de comparación de medias para la fenología por puntos cardinales y correlación entre la precipitación anual y la fenología. Se presentó una correlación positiva de 0,6 entre precipitación y crecimiento vegetativo en el año 2009 y negativa de -0,18 en el año 2010. No se presentaron diferencias en la fenología por puntos cardinales. En el año 2008 las plantas obtuvieron 168,8 kg/planta, lo que ocasionó que en el año 2009 estas presentaran una fuerte brotación vegetativa y baja cosecha (42,4 kg/árbol); mientras que en el año 2010 aumentaron los brotes reproductivos, disminuyeron los brotes vegetativos y la cosecha fue de 147,8 kg/árbol. Se presentó una alternancia en el uso de carbohidratos entre el rendimiento de la planta y la brotación vegetativa. </p><p> </p><p><strong>Alternate bearing and phenology of ‘Valencia’ orange (<em>Citrus sinensis </em>[L.] Osbeck) in the lowland wet tropics of Colombia </strong></p><p>In tropical conditions near the equatorial, precipitation is the main climatic factor that influences the growth and development of citrus plants. In a ‘Valencia’ orange orchard planted with 11-year-old trees located in the higher portion of the foothills of Corpoica, La Libertad Research Center in Villavicencio, Meta, Colombia, we recorded tree production data between the years 2008- 2010. Information on the phenology of ten marked trees was gathered fortnightly from four cardinal directions using the methodology of Garrán <em>et al</em>. (1993) during the years 2009 and 2010. For this same period, the water balance was calculated for this orchard. The data were analyzed with descriptive statistics for most variables, and a mean-comparison test was carried out for the phenology observed at the cardinal points and for the correlation between annual precipitation and phenology. There was a positive correlation of 0.6 between rainfall and vegetative growth in 2009 and a negative correlation of -0.18 in 2010. There were no differences in phenology at the cardinal points. In 2008, the plants produced 168.8 kg/plant, causing the plants to present a strong vegetative growth and low yield (42.4 kg/tree) in 2009, whereas in 2010 there was an increase in the number of reproductive shoots, a decrease in the number of vegetative shoots and the harvest was 147.8 kg/tree. An alternation in the use of carbohydrates was observed between plant yield and vegetative growth. </p>
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Brundrett, Mark C., and Bryce Kendrick. "The mycorrhizal status, root anatomy, and phenology of plants in a sugar maple forest." Canadian Journal of Botany 66, no. 6 (1988): 1153–73. http://dx.doi.org/10.1139/b88-166.
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The phenology, root anatomy, and mycorrhizal colonization of vascular plant species occurring in a hardwood forest site were studied. Sugar maple (Acer saccharum), the dominant tree, ash (Fraxinus americana), another important tree, and the most abundant herbaceous plants were examined periodically. Most of the herbaceous species present were highly colonized by vesicular–arbuscular mycorrhizae (VAM), but some consistently had low levels of VAM, or were nonmycorrhizal, and several had orchid mycorrhizae. Most trees were associated with VAM, although several ectomycorrhizal species occurred in low numbers. Herbaceous plants could be divided into four phenological categories of shoot activity, spring, spring–summer, summer, and fall, but many species had periods of root growth that did not parallel their aboveground activity. Almost all species that produced new roots in summer were well colonized by VAM, while those active mainly in late fall or early spring tended to be nonmycorrhizal. Roots of the woodland plants typically had a well-developed exodermis and also tended to be long-lived and coarse. Possible relationships among these root system characteristics, phenological categories, and levels of mycorrhizal colonization of woodland plants are discussed.
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FISCHER, ERICH, and FLAVIO A. M. DOS SANTOS. "Demography, phenology and sex of Calophyllum brasiliense (Clusiaceae) trees in the Atlantic forest." Journal of Tropical Ecology 17, no. 6 (2001): 903–9. http://dx.doi.org/10.1017/s0266467401001675.
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Further studies on growth and reproduction of many tree species are needed to know the regeneration patterns of tropical forests (Clark & Clark 1987, Heideman 1989). Thus, the need for studies on the c. 3% of Atlantic forest that remains in Brazil is acute, particularly in the rarely studied swamp habitats (Scarano et al. 1997). We studied the canopy tree species Calophyllum brasiliense Camb. (Clusiaceae) in flooded and unflooded habitats of a coastal lowland rain forest, in order to describe demography, sexual expression, phenology and flower and fruit production. We report the differences of such traits among three contiguous habitats found in the lowlands - unflooded forest, freshwater-flooded forest and mangrove.
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Paine, T. D., F. M. Stephen, and R. G. Cates. "Phenology of an induced response in loblolly pine following inoculation of fungi associated with the southern pine beetle." Canadian Journal of Forest Research 18, no. 12 (1988): 1556–62. http://dx.doi.org/10.1139/x88-238.
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Loblolly pines (Pinustaeda L.) growing in two plantations were inoculated with fungi that are associated with the southern pine beetle, Dendroctonusfrontalis Zimm. Trees were sampled at 12-h intervals to determine the rate of formation of induced lesions. After an initial lag of 60 h, trees responded to infection by the blue-staining Ceratocystisminor (Hedgcock) Hunt with rapid lesion growth during the next 24 h. Trees inoculated with either of two mycangial fungi, C. minor var. barrasii Barras & Taylor or the basidiomycete, showed only limited lesion growth. Inoculations of combinations of fungi produced similar temporal patterns of lesion growth, but only combinations that included C. minor induced lesions that were significantly longer after 3 weeks than after 12 h. The data from this study suggest that the highly specialized mycangial fungi do not trigger the hypersensitive response in host trees when compared with sterile wounding, whereas the less adapted or less specialized nonmycangial C. minor does induce lesion formation. The delay in lesion formation also suggests that there is an initial period of increased vulnerability, when the tree may be killed before the induced response is manifested.
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Memmi, Houssem, Jose F. Couceiro, Carmen Gijón, and David Pérez-López. "Impacts of water stress, environment and rootstock on the diurnal behaviour of stem water potential and leaf conductance in pistachio (Pistacia vera L.)." Spanish Journal of Agricultural Research 14, no. 2 (2016): e0804. http://dx.doi.org/10.5424/sjar/2016142-8207.
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Little information is available on the diurnal behaviour of water potential and leaf conductance on pistachio trees despite their relevance to fine tune irrigation strategies. Mature pistachio trees were subject to simultaneous measurements of stem water potential (Ψx) and leaf conductance (gl) during the day, at three important periods of the irrigation season. Trees were grown on three different rootstocks and water regimes. An initial baseline relating Ψx to air vapor pressure deficit (VPD) is presented for irrigation scheduling in pistachio. Ψx was closely correlated with VPD but with a different fit according to the degree of water stress. No evidence of the variation of Ψx in relation to the phenology of the tree was observed. Furthermore, midday Ψx showed more accuracy to indicate a situation of water stress than predawn water potential. Under well irrigated conditions, gl was positively correlated with VPD during stage II of growth reaching its peak when VPD reached its maximum value (around 4 kPa). This behaviour changed during stage III of fruit growth suggesting a reliance of stomatal behaviour to the phenological stage independently to the tree water status. The levels of water stress reached were translated in a slow recovery of tree water status and leaf conductance (more than 40 days). Regarding rootstocks, P. integerrima showed little adaptation to water shortage compared to the two other rootstocks under the studied conditions.
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van der Maaten, Ernst, Jonas Pape, Marieke van der Maaten-Theunissen, et al. "Distinct growth phenology but similar daily stem dynamics in three co-occurring broadleaved tree species." Tree Physiology 38, no. 12 (2018): 1820–28. http://dx.doi.org/10.1093/treephys/tpy042.
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Grimm, Christoph. "Seed predators and the fruiting phenology of Pithecellobium pallens (Leguminosae) in thornscrub, north-eastern Mexico." Journal of Tropical Ecology 11, no. 3 (1995): 321–32. http://dx.doi.org/10.1017/s0266467400008804.
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ABSTRACTLife table studies were conducted on the flowers, pods and seeds of the tree Pithecellobium pallens to assess the extent of damage by the seed predators Stator limbatus and Merobruchus insolitus (Coleoptera: Bruchidae). Brachyacma palpigera (Lepidoptera: Gelechiidae) was also found to feed on the seeds of this tree. Seed predation and herbivore damage destroyed 41% of the seeds. Pods were taken to the laboratory and seed predators within were reared and identified. B. palpigera and M. insolitus were major causes of mortality, whereas damage by S. limbatus was slight. The growth ratio of pods to seeds did not indicate a rapid development of seeds as an evasive strategy against bruchid attack. Experiments showed no successful attack by bruchids on seeds exposed on the ground after dispersal from the tree.
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Picchioni, G. A., P. H. Brown, S. A. Weinbaum, and T. T. Muraoka. "Macronutrient Allocation to Leaves and Fruit of Mature, Alternate-bearing Pistachio Trees: Magnitude and Seasonal Patterns at the Whole-canopy Level." Journal of the American Society for Horticultural Science 122, no. 2 (1997): 267–74. http://dx.doi.org/10.21273/jashs.122.2.267.
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Estimates of leaflet and fruit macronutrient (N, P, K, Ca, and Mg) accumulation and resorption were developed in six (three heavily cropping, on-year and three noncropping, off-year) mature pistachio (Pistacia vera L. `Kerman') trees over three growing seasons during three stages of phenology [the spring growth flush (April to June); seed fill (late June to September); and leaf senescence (September to November)]. Crop load influenced total nutrient content per tree in annual organs (leaves and fruit), the relative allocation of nutrients between leaves and fruit, temporal patterns of nutrient accumulation in annual organs, and the magnitude of net leaf nutrient resorption per tree prior to leaf fall. In off-year trees, macronutrient accumulation in annual organs (leaves) was concentrated during the spring flush of growth. In contrast, significant macronutrient accumulation in annual organs of on-year trees (leaves plus fruit) occurred not only during the spring flush of growth but also during seed fill. Duration and magnitude of macronutrient accumulation were greater in on-year vs. off-year trees. Fruit N and P demand during seed fill was partially met by a net decrease in the N and P contents of the pericarp. These decreases in pericarp nutrient content during seed fill were equivalent to 32% and 26% of embryo accumulation of N and P, respectively. Fruit demand for N, P, and K during the spring flush of “on” years was accompanied by reduced leaf N, P, and K contents per tree. Net leaf N, Ca, and Mg resorption per tree during leaf senescence differed with crop load. Net leaf N resorption was significantly greater in off-year trees than on-year trees. Leaf N resorption presumably represents an important component of the N pool stored in perennial tree parts during dormancy. The greater leaf N resorption following “off” years was a function of greater leaf N concentration and greater leaf biomass per tree. In contrast, net leaf resorption of Ca and Mg was greater in on-year vs. off-year trees. Experimental validation of the magnitude and periodicity of nutrient uptake by mature pistachio trees is needed during the alternate-bearing cycle, especially in light of the potential contribution of current fertilization practices to groundwater contamination.
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Conlin, Timothy S. S., and Victor J. Lieffers. "Seasonal growth of black spruce and tamarack roots in an Alberta peatland." Canadian Journal of Botany 71, no. 2 (1993): 359–60. http://dx.doi.org/10.1139/b93-039.
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Seasonal growth of black spruce (Picea mariana Mill. BSP) and tamarack (Larix laricina (Du Roi) K. Koch) roots in an Alberta peatland were assessed by measuring growth into emplaced soil cores that did not contain plant roots. Five cores were positioned 1 m from the base of each tree and 10 replicates of this treatment were used for each species. Sequential lifting of these cores during the growing season showed that root growth by these species did not begin until midsummer. Tamarack root growth was restricted to August and September, while black spruce root growth continued into October. Key words: flooding, Larix laricina, peatland, phenology, Picea mariana, temperature, root growth.
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de-Dios-García, Javier, Rubén Manso, Rafael Calama, Mathieu Fortin, and Marta Pardos. "A new multifactorial approach for studying intra-annual secondary growth dynamics in Mediterranean mixed forests: integrating biotic and abiotic interactions." Canadian Journal of Forest Research 48, no. 4 (2018): 333–44. http://dx.doi.org/10.1139/cjfr-2017-0139.
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Studying intra-annual growth dynamics through a modelling approach has proved useful for characterizing differences in wood phenology between species and deviations from the expected tree growth due to climate change. The aim of this paper was to determine the climatic factors and the inter- and intra-specific competition traits that drive intra-annual secondary growth dynamics in three Mediterranean tree species that naturally co-exist in the Spanish Northern Plateau (Pinus pinea L., Juniperus thurifera L., and Quercus ilex subsp. ballota (Desf.) Samp.). For this purpose, we obtained girth increment data from band dendrometers installed on 58 trees from May 2012 to April 2015. Half of them were located in a high-density plot and half were in a low-density plot. These data were analysed through a nonlinear multifactorial model considering daily and cumulative climatic effects together with inter- and intra-specific competition indices. Our results provide evidence of a spatiotemporal niche separation between species. Compared with other species, Q. ilex subsp. ballota showed a wider thermal amplitude, a higher mean optimum temperature for growth, and a milder effect of drought on its secondary growth. Under current climate change projections, simulations based on our model predict a secondary growth reduction for P. pinea and a growth enhancement for Q. ilex subsp. ballota in these Mediterranean mixtures.
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YESHITELA, T., P. J. ROBBERTSE, and J. FIVAS. "EFFECTS OF FRUIT THINNING ON ‘SENSATION’ MANGO (MANGIFERA INDICA) TREES WITH RESPECT TO FRUIT QUANTITY, QUALITY AND TREE PHENOLOGY." Experimental Agriculture 40, no. 4 (2004): 433–44. http://dx.doi.org/10.1017/s0014479704002091.
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Different fruit thinning methods were tested on ‘Sensation’ mango trees over two seasons in a trial conducted in Northern Province, South Africa. The objective of the study was to select the best thinning intensity and method based on different parameters. Thinning was carried out in October prior to the occurrence of excessive natural fruit drop. When fruits were thinned to one and two fruits per panicle, fruit number, weight and yield per tree at harvest were all increased. When 50% of the panicles were thinned there was an increase in the fruit retention potential of the trees as well as in the size and quality of the fruit produced. Large fruits were, however, prone to certain physiological problems. Chemical thinning with Corasil.E produced very small fruits with an increased percentage of ‘mules’ (fruit without seed). Trees subjected to severe thinning intensities showed earlier recovery of starch reserves and better vegetative growth than the control.
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de Wergifosse, Louis, Frédéric André, Nicolas Beudez, et al. "HETEROFOR 1.0: a spatially explicit model for exploring the response of structurally complex forests to uncertain future conditions – Part 2: Phenology and water cycle." Geoscientific Model Development 13, no. 3 (2020): 1459–98. http://dx.doi.org/10.5194/gmd-13-1459-2020.
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Abstract. Climate change affects forest growth in numerous and sometimes opposite ways, and the resulting trend is often difficult to predict for a given site. Integrating and structuring the knowledge gained from the monitoring and experimental studies into process-based models is an interesting approach to predict the response of forest ecosystems to climate change. While the first generation of models operates at stand level, one now needs spatially explicit individual-based approaches in order to account for individual variability, local environment modification and tree adaptive behaviour in mixed and uneven-aged forests that are supposed to be more resilient under stressful conditions. The local environment of a tree is strongly influenced by the neighbouring trees, which modify the resource level through positive and negative interactions with the target tree. Among other things, drought stress and vegetation period length vary with tree size and crown position within the canopy. In this paper, we describe the phenology and water balance modules integrated in the tree growth model HETEROFOR (HETEROgenous FORest) and evaluate them on six heterogeneous sessile oak and European beech stands with different levels of mixing and development stages and installed on various soil types. More precisely, we assess the ability of the model to reproduce key phenological processes (budburst, leaf development, yellowing and fall) as well as water fluxes. Two two-phase models differing regarding their response function to temperature during the chilling period (optimum and sigmoid functions) and a simplified one-phase model are used to predict budburst date. The two-phase model with the optimum function is the least biased (overestimation of 2.46 d), while the one-phase model best accounts for the interannual variability (Pearson's r=0.68). For the leaf development, yellowing and fall, predictions and observations are in accordance. Regarding the water balance module, the predicted throughfall is also in close agreement with the measurements (Pearson's r=0.856; bias =-1.3 %), and the soil water dynamics across the year are well reproduced for all the study sites (Pearson's r was between 0.893 and 0.950, and bias was between −1.81 and −9.33 %). The model also reproduced well the individual transpiration for sessile oak and European beech, with similar performances at the tree and stand scale (Pearson's r of 0.84–0.85 for sessile oak and 0.88–0.89 for European beech). The good results of the model assessment will allow us to use it reliably in projection studies to evaluate the impact of climate change on tree growth in structurally complex stands and test various management strategies to improve forest resilience.
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Clarke, PJ, and PJ Myerscough. "Floral Biology and Reproductive Phenology of Avicennia marina in South-Eastern Australia." Australian Journal of Botany 39, no. 3 (1991): 283. http://dx.doi.org/10.1071/bt9910283.
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Flowering, pollination and reproductive phenology of the tree, Avicennia marina (Grey mangrove), were examined on the south-east coast of Australia in New South Wales. Individual flowers are protandrous and open for 2-5 days, while a flower cluster has open flowers for 2-4 weeks. About 16000 pollen grains and four ovules are produced per flower. Self-pollination of an individual flower is unlikely because of protandry, but the sequence and synchrony of flowering, together with pollinator behaviour, favour geitonogamy. Some fruit is set when cross-pollination is restricted by bagging flowers, which indicates partial self-compatibility. Subsequently, fruit abortion is higher in the bagged treatment than in those open-pollinated; this may reflect some pre-dispersal inbreeding depression. Between 4 and 41% of open-pollinated flower buds set fruit, most of which had one or rarely two seeds. Phenologically, each reproductive stage is unimodal and the whole process from bud initiation to abscission of mature fruit is completed within a year. Initiation of floral buds, flowering, growth and abscission of fruits are almost synchronous among fecund trees at a particular latitude each year. Latitudinal differences occur consistently among populations that are separated by less than 2° of latitude; those at lower latitudes flower earlier. Flowering of individual trees varies greatly between years and many trees fail to reproduce each year, although the populations remain fecund from year to year. A flexible breeding system and regular population fecundity ensure annual propagule supply in the populations studied.