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Soil physical-chemical characteristics are key factors to intraspecific variability in plant functional traits. However, little is known about how wood and leaf traits can interact to ensure similar tree growth and wood quality in sites with different edaphoclimatic conditions. Here, we investigated the effect of soil on the wood features, leaf traits, and plant growth in Eucalyptus urophylla and E. urophylla x grandis trees. We evaluated the wood features, leaf traits and tree growth in 20 six-year-old trees from the same clone of each species. We applied linear models to verify the variability in these characteristics for both clones in two trial sites. Wood with larger vessels in a lower density, higher potential hydraulic conductivity, taller and wider rays, a higher fraction of vessels and parenchyma cells and a lower fraction of fibers were observed in trees from the trial site with higher availability of water and nutrients. Moreover, the trees had lower specific leaf area and higher leaf dry matter content in this trial site. Our results show that trees studied have similar wood features that ensure safety and relative efficiency in water transport. In addition, we found different leaf traits strategies to optimize carbon uptake, thus maintaining similar productivity and wood quality in sites with different soil conditions.

Made available in DSpace on 2020-12-12T02:21:19Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-09-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Intraspecific studies with populations replicated in different sites allow the effects of genotype and environment on wood features and plant growth to be distinguished. Based on climate change predictions, this distinction is important for establishing future patterns in the distribution of tree species. We quantified the effects of genotype and environment on wood features and growth of 30-year-old Balfourodendron riedelianum trees. We used three provenances planted in two common garden experiments with difference in precipitation and temperature. We applied linear models to estimate the variability in wood and growth features and transfer functions to evaluate the responses of these features to temperature, precipitation, and the standardized precipitation evapotranspiration index (SPEI). Our results showed that genotype had an effect on vessels and rays, where narrower vessels with thinner walls and larger intervessel pits, and shorter, narrower and more numerous rays were observed in provenances from drier sites. We also observed the effect of the environment on wood features and growth. Trees growing in the wetter site were taller and larger, and they had wider vessels with thicker walls and lower ray density. Transfer functions indicated that an increase in temperature results in larger vessels with thicker walls, taller and denser rays, shorter and narrower fibers with thinner walls, and lower wood density. From a functional perspective, these features make trees growing in warmer environments more prone to drought-induced embolisms and more vulnerable to mechanical damage and pathogen attacks. Tree growth varied with precipitation and SPEI, being negatively affected in the drier site. Overall, we demonstrated that both genotype and environment affect wood features, while tree growth is mainly influenced by the environment. Plastic responses in hydraulic characteristics could represent important functional traits to mitigate the consequences of ongoing climate change on the growth and survival of the species within its natural range. Laboratório de Anatomia da Madeira Departamento de Ciência Florestal Solos e Ambiente Faculdade de Ciências Agronômicas Universidade Estadual Paulista (UNESP), Câmpus de Botucatu Département des Sciences Fondamentales Université du Quebec à Chicoutimi Instituto Florestal Laboratório de Anatomia da Madeira Departamento de Ciência Florestal Solos e Ambiente Faculdade de Ciências Agronômicas Universidade Estadual Paulista (UNESP), Câmpus de Botucatu FAPESP: 2015/14954-1

Fire is common in seasonally dry areas in many parts of the world, and its effects on vegetation in these areas have been well studied. In riparian forests of the Pantanal, where fuel accumulation (dead plants) in the dry season can be a substantial driver of fire occurrence, little is known about the role of bark traits to fire protection in woody plants. Herein we evaluated some physical, chemical and anatomical bark traits to determine if they are associated with fire tolerance in tree riparian species of the Pantanal. To accomplish this, we selected three fire-sensitive species and seven fire-tolerant species in riparian forest of the Paraguay River. Bark samples were analyzed for relative total, outer and inner bark thickness, bark density, concentration of phenolic compounds and tannins, thermogravimetric behavior and their anatomical structure. We observed higher concentration of phenol and tannins and higher percentage of sclerenchyma in bark from fire-tolerant species than fire-sensitive species. Bark of fire-tolerant species also showed more sclerenchyma cells near vascular cambium and higher temperatures of thermal decomposition. In contrast, relative total, outer and inner bark thickness, and bark density did not differ between species groups. The high concentration of phenol and tannins, combined with higher percentage of sclerenchyma in secondary phloem, appear as the major bark traits that could mitigate fire damage in species from riparian forest of the Brazilian Pantanal.

Resprouting from belowground buds is an important mechanism to increase aboveground branching. This trait is particularly frequent in various members of Fabaceae. However, there are scant anatomical studies on belowground buds including information about their location in the plant body in these species. Herein we examined the anatomy of belowground buds and organs that support these buds in herbaceous and woody Fabaceae species. Adventitious buds located in the root-shoot transition zone (root crown) were the predominant type of belowground buds in herbaceous and subshrubby species. Moreover, some woody species showed lateral roots with root buds growing near the soil surface. The root structure was confirmed by the centripetal maturation of the primary xylem (exarch xylem). Anatomical analyses of Cenostigma pluviosum and Senna pilifera roots revealed numerous reparative buds that develop from calli. Reparative buds were formed only after injury to root tissues or shoot removal. On the other hand, the roots of Machaerium eriocarpum and Muellera nudiflora showed additional buds with bud traces connected to the primary xylem. Additional buds were found in uninjured young roots and in root segments that were kept in a greenhouse condition. Our findings show that the species examined of Fabaceae are able to resprout from adventitious buds located in roots and root crowns. This trait seems to be advantageous for conservation of these species in the Brazilian Chaco, which is characterised by dry seasons associated with frost and extensive cattle raising.

Made available in DSpace on 2018-12-11T17:14:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-01-01 Fundação de Amparo à Pesquisa do Estado do Amazonas Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Stems and roots are interconnected by their secondary phloem, a complex tissue that exhibits functional differences related to the anatomical structure of each organ. Here, we compared the structure of secondary phloem in mature stems and roots of Citharexylum myrianthum Cham. (Verbenaceae). We sampled the main stems at a height of 1.3 m and the roots at a depth of 0.5 m. We described both the qualitative and quantitative features of all secondary phloem cell types, and compared the quantitative features using a paired Student’s t test. The same percentage of sieve tubes in the conducting phloem between the organs indicates a similar conducting efficiency between stem and roots, even though sieve tubes have wider diameters in the stems. Overall, stems had a higher portion of nonconducting secondary phloem than the roots, with a higher number of both parenchyma and sclerenchyma bands, likely indicating a higher storage and support potential of the phloem in stems. Universidade Estadual Paulista (UNESP) Instituto de Biociências de Botucatu, Câmpus de Botucatu, Distrito de Rubião Junior Universidade Estadual Paulista (UNESP) Faculdade de Ciências Agronômicas Laboratório de Anatomia da Madeira, Câmpus de Botucatu, Rua José Barbosa de Barros, 1780 Universidade Estadual Paulista (UNESP) Instituto de Biociências de Botucatu, Câmpus de Botucatu, Distrito de Rubião Junior Universidade Estadual Paulista (UNESP) Faculdade de Ciências Agronômicas Laboratório de Anatomia da Madeira, Câmpus de Botucatu, Rua José Barbosa de Barros, 1780 Fundação de Amparo à Pesquisa do Estado do Amazonas: 04/05913-5 CNPq: 503425/2005-2