DSpace Angular :: Browsing by Author "Rubilar, Rafael"

Browsing by Author "Rubilar, Rafael"

Now showing 1 - 15 of 15

Changes in leaf physiology for eucalyptus genotypes with increase in integral water stress and its consequence for initial growth in central Chile
(2022) Goncalves de Oliveira, Thiago Wendling; Rubilar, Rafael; Sanquetta, Carlos Roberto; Dalla Corte, Ana Paula; Bozo, Daniel; Medina, Alex; Mardones, Oscar; Emhart, Veronica; Quiroga, Juan Jose; Valenzuela, Hector
Limited information exists on how small changes in soil water affect the physiological responses of eucalyptus and their relationship with productivity. This experiment evaluated physiological traits during decreased soil water and compared them with growth and water stress integral (WSI) of 22 eucalyptus genotypes with 1.5 years old. The experiment was conducted in sandy soil with low water holding capacity in Chile. Selected genotypes were Eucalyptus globulus, E. nitens, and E. nitens x E. globulus hybrids (E. gloni). Seasonal predawn leaf water potential (psi(pd)) was evaluated under well-irrigated conditions and after 40 days without irrigation. Subsequently, two sampling instances were considered for analysis, well-irrigated conditions M-0 (470 days after planting) and 40 days without irrigation M-final (510 days after planting). During that period, we measured midday leaf water potential (psi(pd)), leaf area index (LAI), diurnal changes in photosynthesis (A(n)) and stomatal conductance (g(s)). The broad range of WSI among genotypes indicated contrasting levels of accumulated water stress during early development. In fact, E. globulus presented 30% more water stress than E. nitens, and genotypes with the highest WSI showed the lowest growth. Between M-0 and M-final, there was a reduction in A(n) and g(s) in the morning and midday with small changes in the afternoon, and consequently, values of the intrinsic water use efficiency (iWUE) increased. The psi(pd) showed small changes and we observed a large LAI increment for all genotypes. Changes in iWUE were more pronounced for genotypes with lower WSI, which suggested that these genotypes with lower accumulated water stress were more sensitive to changes in soil water, such as E. gloni genotypes allowing them to maintain high productivity.
Constitutive and inducible defense in Eucalyptus determines the feeding host of Gonipterus platensis, denoting specific plant-insect coevolution and a strategy for resistance improvement
(2022) Campos, Jasna V.; Riquelme, Sebastian; Pecio, Lukas; Guedes, Lubia; Mardones, Claudia; Alzamora, Rosa; Arteaga-Perez, Luis E.; Rubilar, Rafael; Fiehn, Oliver; Perez, Andy J.
Defoliation caused by Gonipterus platensis on Eucalyptus seriously impacts tree growth rate and forest production. The weevil's feeding preference has sometimes limited which species of Eucalyptus to plant, although the plant's metabolic features that govern such choice still need to be uncovered. We used metabolomics to reveal the chemical traits mediating this interaction, focusing on a model formed by two Eucalyptus species with markedly different susceptibility, E. globulus (susceptible), and E. nitens (resistant). Our results suggest that the insect's feeding preference strongly depends on the Eucalyptus species' constitutive metabolome, especially on the stilbenes and hydrolysable tannins accumulation. The susceptible E. globulus could not produce such classes of metabolite either constitutively or after herbivory, which indicated an apparent lack of critical enzymes for biosynthesis of these substances, such as stilbene synthase (STS) and gallate 1-beta-glucosyltransferase. On the other hand, it seems that no matter how toxic the systemic defense induced in E. globulus after herbivory could be to an insect, counteradaptations, apparently evolved by the weevil, may efficiently detoxify them. This may result from plant-insect coevolution, given their common geographical origin. Inter-specific hybridizations between E. nitens and E. globulus have adapted hybrid species better to low temperatures and frost conditions, consequently being propagated for plantations in temperate regions. Thus, this research lays the groundwork for selecting the best parent genotypes and obtained hybrids, aiming to warrant the transfer of key resistance traits to progenies as an attractive strategy for future breeding programs.
Detection of Phytophthora cinnamomi on declining Araucaria araucana forests
(2022) Sanfuentes, Eugenio; Gonzalez, Mariela; Castillo, Miguel; Rubilar, Rafael; Besoain, Ximena; Sanhueza, Claudia; Smith, Milena
Since 2016, crown death and mortality of Araucaria araucana trees have been observed at different localities of the Nahuelbuta Coastal Range, Chile. The objective of this study was to determine the presence of Phytophthora spp. in the rhizosphere of A. araucana trees that may explain its decline. Samples of soil rhizosphere were collected from trees with crown death as well as from asymptomatic trees at two visually contrasting severity areas. Phytophthora detection from soil samples was carried out using leaf bait technique, and isolates were identified by morphology and molecular methods. Recovered Phytophthora isolates were used in pathogenicity tests with A. araucana plants. From rhizosphere soil samples of 30 A. araucana trees, 56 isolates of Phytophthora cinnamomi were obtained. Isolations were more frequent in the rhizosphere of trees with severe crown symptoms and originated exclusively from the selected area showing severe crown symptoms. Plant stem inoculation with P. cinnamomi isolates caused 100% mortality; however, through root infestation, mortality was variable depending on the specific isolate. These results are the first report of the pathogenicity of P.cinnamomi A2 in natural forests of A. araucana in Chile.
Differences in rainfall interception among Eucalyptus genotypes
(2023) Valverde, Juan Carlos; Rubilar, Rafael; Barrientos, Guillermo; Medina, Alex; Pincheira, Matias; Emhart, Veronica; Zapata, Alvaro; Bozo, Daniel; Espinoza, Yosselin; Campoe, Otavio C.
Key messageHydrological indicators such as rainfall interception of Eucalyptus genotypes are essential to guarantee the water sustainability of forest plantations under climate change scenarios.Rainfall interception is a critical component of water balance in Eucalyptus plantations and may provide better water sustainability by reducing potential adverse effects under drought scenarios. This study evaluated rainfall interception of Eucalyptus globulus and E. nitens x globulus (high and low yield), E. nitens, E. badjensis, E. smithii, and E. camaldulensis x globulus. Rainfall, stemflow, throughfall, and interception (calculated as rainfall-stemflow-throughfall) were measured for 2 years (2020-2022) and correlated with plantation characteristics [diameter at breast height, total height, stem growth, and leaf area index (LAI)]. Our results showed an average rainfall of 1063.6 mm year(-1); only stemflow did not show differences among genotypes with an average value of 193.4 mm year(-1) (18.2% of annual rain). In contrast, throughfall and interception presented significant differences among genotypes, and both parameters showed a strong relationship with LAI. Therefore, three independent groups were obtained: E. badjensis and E. smithii showed the highest LAI (average 5.7 m(2) m(-2)) with 517.0 mm year(-1) of average interception and 427.6 mm year(-1) of average throughfall (48.6% and 40.2% respectively). For E. globulus (low-yield), E. nitens x globulus (low-yield), and E. nitens, that showed the lowest LAI (average 3.3 m(2) m(-2)), average throughfall reached 730.8 mm year(-1) (68.7%), and average interception reached 197.3 mm year(-1) (18.5%). Finally, E. globulus (high-yield), E. nitens x globulus (high-yield), and E. camaldulensis x globulus with an average LAI of 4.5 m(2) m(-2), average interception reached 345.2 mm year(-1) (32.5%), and average throughfall reached 602.7 mm year(-1) (56.7%). Our results suggest that understanding differences between taxas/genotypes may contribute to developing hydrological indicators that may improve estimates of plantation water sustainability under water scarcity climate change scenarios.
Drought and Wildfire Trends in Native Forests of South-Central Chile in the 21st Century
(2024) Duarte, Efrain; Rubilar, Rafael; Matus, Francisco; Garrido-Ruiz, Claudia; Merino, Carolina; Smith-Ramirez, Cecilia; Aburto, Felipe; Rojas, Claudia; Stehr, Alejandra; Dorner, Jose; Najera, Francisco; Barrientos, Guillermo; Jofre, Ignacio
Over the last decades, Chile has experienced a long-term drought with significant consequences for water availability, forest productivity, and soil degradation, ultimately dramatically increasing the surface of burned area. Here, we quantify the Palmer Drought Severity Index (PDSI) to ascertain the extent of "moisture deficiency" across the central-southern region of Chile from 2000 to 2023 to assess the drought's relationship with the frequency of wildfires focusing on the impact of native forests. Our methodology quantifies the PDSI from the burned area data using MODIS MCD64A1 satellite imagery, validated by in situ wildfire occurrence records. The findings indicate that 85.2% of fires occurred under moderate to severe drought conditions. We identified 407,561 ha showing varying degrees of degradation due to wildfires, highlighting the critical areas for targeted conservation efforts. A significant increase in both the frequency of wildfires and the extent of the affected area in native forests was observed with the intensification of drought conditions in the 21st century within mesic to humid Mediterranean climatic zones where drought explains up to 41% of the variability in the burned area (r(2) = 0.41; p < 0.05). This study highlights the relationship between drought conditions and wildfire frequency, showing the paramount need to adopt comprehensive wildfire mitigation management in native forests.
Extracted Eucalyptus globulus Bark Fiber as a Potential Substrate for Pinus radiata and Quillaja saponaria Germination
(2024) Ferrer-Villasmil, Victor; Fuentealba, Cecilia; Reyes-Contreras, Pablo; Rubilar, Rafael; Cabrera-Barjas, Gustavo; Bravo-Arrepol, Gaston; Escobar-Avello, Danilo
This study aimed to explore alternative substrates for growing forest species using eucalyptus bark. It evaluated the potential of extracted Eucalyptus globulus fiber bark as a substitute for commercial growing media such as coconut fiber, moss, peat, and compost pine. We determined the physicochemical parameters of the growing media, the germination rate, and the mean fresh and dry weights of seedlings. We used the Munoo-Liisa Vitality Index (MLVI) test to evaluate the phytotoxicity of the bark alone and when mixed with commercial substrates. Generally, the best mixture for seed growth was 75% extracted eucalyptus bark fiber and 25% commercial substrates. In particular, the 75E-25P (peat) mixture is a promising substitute for seedling growth of Pinus radiata, achieving up to 3-times higher MLVI than the control peat alone. For Quillaja saponaria, the best growth substrate was the 50E-50C (coconut fiber) mixture, which had the most significant MLVI values (127%). We added chitosan and alginate-encapsulated fulvic acid phytostimulants to improve the performance of the substrate mixtures. The fulvic acid, encapsulated or not, significantly improved MLVI values in Q. saponaria species and P. radiata in concentrations between 0.05 and 0.1% w/v. This study suggests that mixtures with higher levels of extracted fiber are suitable for growing forest species, thus promoting the application of circular economy principles in forestry.
Sirex noctilio infestation led to inevitable pine death despite activating pathways involved in tolerance
(2022) Riquelme, Sebastian; Campos, Jasna, V; Pecio, Lukasz; Alzamora, Rosa; Mardones, Claudia; Simonet, Ana M.; Arteaga-Perez, Luis E.; Rubilar, Rafael; Fiehn, Oliver; Perez, Andy J.
Defense-related metabolome traits in pine species after infestation by Sirex noctilio are largely unknown, despite, in most cases, trees being overwhelmed. Using LC-MS-based untargeted metabolomics, we revealed the systemic metabolic changes induced by this insect in 14-year-old Pinus radiata trees, the most affected species worldwide. An immediate metabolome alteration was expressed in needles after infestation, including the up-regulation of flavonols, flavan-3-ols, oxyneolignans, auxins, proline, and tryptophan, among others. The flavan-3-ols (catechin and procyanidin B1) suggested a rapidly induced photoprotection mechanism aided by diverting proline as an alternative substrate for respiration to compensate for the progressive chlorosis that degrades photosystems. Meanwhile, glutathione, glutamate, and ascorbate levels significantly dropped in needles, which may indicate the critical oxidative stress that trees had to face since the onset of the infestation. They were not fully replenished after long-term infestation, and redox homeostasis was probably not achieved, compromising tree survival. Nevertheless, a huge auxins overexpression detected in needles throughout the infestation may reflect tolerance against the premature senescence caused by the woodwasp venom. In contrast, the metabolome of wood tissues remained initially unchanged, although it seems to collapse after three months. Overall, the metabolomics strategy adopted in this work evidenced its usefulness in uncovering the fundamental roles of plants' chemical defense that govern interactions with specific stressors.
Life cycle analysis to estimate CO₂e emissions from forest harvesting systems in intensively managed Pinus radiata plantations
(2022) Alzamora, Rosa M.; Oviedo, Waldo; Rubilar, Rafael
A Life Cycle Analyses (LCA) assessment was evaluated comparing three harvesting systems on intensively managed Pinus radiata (radiata pine) plantations growing in the Biobio Region, Chile. Evaluated systems considered semi-mechanized, mechanized, and tower logging in steep slope forest operations. Our LCA study focused on CO(2)e emissions from six harvesting activities: felling, logging, processing, sorting, loading, and transportation, all under the ISO 14040 and ISO 14044 standards. The average and maximum monthly production scenarios were the highest for the semi-mechanized system with 24 and 25.2 kg CO(2)e m(-3), followed by the tower logging with 23.2 and 24.5 kg CO(2)e m(-3) and, lastly, the mechanized system with 11 and 12.1 kg CO(2)e m(-3). Similar to other studies, harvesting phases that contributed the most were logging, loading and transport. Concerning LCA stages, forest equipment operation generated the highest CO(2)e level across the three harvesting systems where fuel consumption was the activity that contributed with 76% of CO(2)e for the mechanized system, and 50% in the case of the tower logging and semi-mechanized systems. The mechanized system had the highest fuel use efficiency and the lowest CO(2)e emissions.
Morphological, physiological and carbon balance response of Eucalyptus genotypes under water stress
(2024) Garcia, Luz Yeidy; Rubilar, Rafael; Valverde, Juan Carlos; Emhart, Veronica; Bascunan, Luisa; Medina, Alex; Bozo, Daniel
Water stress is considered one of the main environmental factors that limit survival and productivity of Eucalyptus plantations. Identifying genotypes traits that provide evidence of tolerance to water stress may allow sustained productivity and secure better resilience of forest plantations under climate change in Mediterranean environments. Our study analyzed morphological, physiological, and carbon (C) balance responses of ten Eucalyptus genotypes under contrasting water regimes under nursery conditions. One-year-old cuttings of Eucalyptus nitens (En1 and En2), E. smithii (Es), E. badjensis (Eb), E. nitens x globulus (Eng1, Eng2, Eng3, and Eng4), E. globulus (Eg), and E. camaldulensis x globulus (Ecg) were evaluated under progressive drought from well-watered (soil water potential close to 0 MPa) to severe water stress (soil water potential close to - 2.5 MPa) conditions. Absolute growth rate (root collar diameter, height, shoot: root biomass ratio), net photosynthesis, stomatal conductance, transpiration, intrinsic water use efficiency (iWUE), predawn water potential (Psi(pd)) and C balance (flux and partitioning) were evaluated. As expected, water stress significantly reduced growth and physiological activity for all genotypes. Of all evaluated parameters iWUE and Psi(pd) were the key grouping physiological and growth response variables among genotypes. Genotypes En1, Eng3, and Eng4 were considered tolerant genotypes, with the smallest physiological change and larger morphological growth. Genotypes En2, Es, Eng1 and Eng2 were moderately tolerant showing intermediate responses compared to other groups. In contrast, Eg, Eb, and Ecg were considered highly sensitive, with major changes in morphology and physiological variables over time. Our results suggest that nursery stage physiological evaluation of genotypes may allow selection for sites with water resource availability risks and may allow to reduce mortality and early establishment productivity losses under drier climate change scenarios.
Nature vs. nurture: Drivers of site productivity in loblolly pine (Pinus taeda L.) forests in the southeastern US
(2024) Ribas-Costa, Vicent A.; Gaston, Aitor; Bloszies, Sean A.; Henderson, Jesse D.; Trlica, Andrew; Carter, David R.; Rubilar, Rafael; Albaugh, Timothy J.; Cook, Rachel L.
Forest productivity is one of the most important aspects of forest management, landscape planning, and climate change assessment. However, although there are multiple elements known to affect productivity, most of them rely on the "nature" of the edaphic, climatic, and geographic conditions, and only some specific aspects can be modified through forest management or "nurture". Through evaluation of site resource availability and an understanding of the main drivers of productivity, management can present solutions to overcome site resource limitations to productivity. Therefore, understanding the implications of a specific management regime requires understanding what drives productivity across large spatial extents and among different management regimes. In this study, we used data from over 1 million hectares of industrial forestland, covering over 6000 different soils and several management regimes of Pinus taeda L. plantations, as well as plot-based data from the Forest Inventory and Analysis (FIA) program, facilitating a comparison of planted and natural Pinus taeda stands. Combined with US Geological Survey LiDAR data, we computed site index and generated wall-to-wall productivity maps for planted Pinus taeda stands in the southeastern US, as well as point-based site index estimates for the FIA dataset. We modeled site index using a random forest algorithm considering edaphic, geologic, and physiographic province information based on the Forest Productivity Cooperative "SPOT" system, and also included climate and management history data. Our model predicted site index with an R2 of 0.701 and RMSE of 1.41 m on the industrial data and R2 of 0.417 and RMSE of 1.84 m for the FIA data. We found that year of establishment of the forest, physiographic province, and geology, were the most important drivers of site index. The soil classification modifier indicating root restrictions were the most important soil-specific variable. Additionally, we found an average increase in site index of 3.05 m since the 1950s for all FIA data, and an average increase of 4.73 m for all industrial data since the 1970s. For the latest period analyzed (2000-2012), average site index in planted FIA plots was 1.2 m higher than naturally regenerated FIA plots, and site index in all industrial forestland had a site index almost 3 m greater than planted FIA plots. Overall, we believe this work sets the foundation for better understanding of forest productivity and highlights the importance of intensive silviculture to improve productivity, and as an additional tool to achieve the economic, environmental, and social objectives.
Rotation-age effects of subsoiling, fertilization, and weed control on radiata pine growth at sites with contrasting soil physical, nutrient, and water limitations
(2023) Rubilar, Rafael; Bozo, Daniel; Albaugh, Timothy; Cook, Rachel; Campoe, Otavio; Carter, David; Allen, H. Lee; Alvarez, Jose; Pincheira, Matias; Zapata, Alvaro
Although short- and medium-term responses to early silvicultural treatments have been documented, few studies show productivity gains or losses throughout a rotation across a range of soil types and resource availability. We evaluated the rotation length productivity responses of radiata pine to subsoiling, fertilization, and weed control in dry sand (DS), red clay (RC), and recent volcanic ash (RV) soils representing a gradient of physical, nutrient, and water limitations. Stands were planted in 2000 in a split-plot factorial design, with soil preparation (subsoiling vs. shovel planting) as the main plot and fertilization at planting (B only vs. NPKB) and weed control (none vs. 2-year banded application) as factorial randomized treatment plots within the main plots. Annual diameter at breast height, height, survival, and cumulative volume responses were measured. The rotation-age results for cumulative volume showed that early gains from weed control were maintained through at least 15 years of age. At rotation age, weed control increased the cumulative volume at the DS site (56 m3/ha, 20% gain), and the response over time was maintained at the RC site (28 m3/ha, 8% gain), whereas the volume was reduced at the RV site (-36 m3/ha, 7% loss). Fertilization resulted in the greatest response at the RC site (29 m3/ha, 8% gain); there were small responses at the DS site (5 m3/ha, 2% gain) and negative responses at the RV site (-18 m3/ ha, 4% loss). Interestingly, subsoiling resulted in null or negative responses at all sites, and negative effects increased over time, with volume responses ranging from -4 m3/ha (1% loss) and -27 m3/ha (7% loss) at the DS and RC sites, respectively, to -116 m3/ha (21% loss) at the RV site. Carrying capacity was reached at midrotation at the RV site and resulted in negative treatment effects at rotation age, suggesting the need for thinning or a younger harvest age at this site. Given the negative or null effects of soil preparation, a better understanding is needed for how this silvicultural treatment is affected by soil type and soil strength.
Runoff variation and progressive aridity during drought in catchments in southern-central Chile
(2023) Barrientos, Guillermo; Rubilar, Rafael; Duarte, Efrain; Paredes, Alberto
Persistent drought events frequently intensify the aridity of ecosystems and cause catchment runoff depletion. Here, using large and long-term data sets of meteorological and hydrologic variables (precipitation, runoff, temperature, and potential evapotranspiration) investigated the major causes that modulated catchment runoff depletion between years 1980 and 2020 in southern-central Chile. We identify the hydrological years where aridity index intensified and analyzed its relationship with annual runoff, and evaluated the effect of the annual evaporation index and annual aridity index on water balance of 44 catchments with different precipitation regimes located between 35 degrees and 40 degrees S. Our results showed that observed precipitation and runoff significantly decreased between 1980 and 2020 in 64% of the catchments in the study area. Potential evapotranspiration increased significantly in 39% of the catchments. Hydrological years in which precipitation decreased, showed a decreased runoff trend. This result suggests that meteorological droughts tend to significantly decrease observed runoff. The runoff value decreased as the aridity index increased from 0.3 to 6.7, and the Budyko curve captured 98.5% of the annual variability of all catchments.
Sodium alginate-g-polyacrylamide hydrogel for water retention and plant growth promotion in water-deficient soils
(2024) Pettinelli, Natalia; Sabando, Constanza; Rodriguez-Llamazares, Saddys; Bouza, Rebeca; Castano, Johanna; Valverde, Juan Carlos; Rubilar, Rafael; Frizzo, Marcela; Recio-Sanchez, Gonzalo
Natural polymer-based hydrogels are preferred as soil water retention agents due to their inherent biocompatibility and biodegradability. Generally, these natural polymers are chemically modified by graft polymerization of vinyl monomers to improve their water absorption and retention properties. Among the polysaccharides used to prepare natural hydrogels, those based on sodium alginate (Alg) stand out for their high-water absorption and retention capacity, as well as for their ability to promote plant growth. The main objective of this study was to develop a biodegradable alginate-based hydrogel as a water retainer to promote plant growth under water deficit conditions. The synthesis was achieved by grafting poly(acrylamide) (PAM) onto Alg backbone, using bisacrylamide as chemical crosslinker and different ratios of alginate:acrylamide (Ac). In addition, Eucalyptus nitens seedlings were used as a model plant to evaluate the effect of alginate-g-polyacrylamide (Alg:PAM) hydrogel application to the growing medium on plant survival, growth, and physiological responses under both wellwatered and water-deficient soil conditions. The maximum degree of swelling (65 g/g) was obtained for the hydrogel prepared. The pseudo-second order model described the water uptake kinetics of the hydrogel. The degradability of Alg:PAM hydrogel reached up to 85 % in 5 weeks in soil and occurs by breaking the glycosidic bonds of the alginate. The E. nitens seedlings cultivated with different doses of Alg:PAM hydrogel (4:1 Alg:Ac) showed higher values of height and root diameter relative growth, survival and photosynthetic responses in comparison to non-treated plants. The results indicate that Alg:PAM hydrogel (4:1 Alg:Ac) has promising applications in forestry as a water retention and seedling growth promoter under water deficient conditions.
Taper and individual tree volume equations of Eucalyptus varieties under contrasting irrigation regimes
(2022) Valverde, Juan Carlos; Rubilar, Rafael; Medina, Alex; Mardones, Oscar; Emhart, Veronica; Bozo, Daniel; Espinoza, Yosselin; Campoe, Otavio
Background: Compatible taper and volume equations are key for traditional growth and yield and current process-based or hybrid models. However, most equations do not consider variables such as genotype, water regime and their interaction, limiting the development of general equations for species or regions. Our research investigated taper and individual tree volume equations for eight Eucalyptus genotypes (E. nitens, E. badjensis, E. smithii, E. camaldulensis x globulus and two varieties of low and high productivity of E. globulus and E. nitens x globulus), all materials are growing under summer irrigated vs. no irrigated conditions.
Wood Basic Density Assessment of Eucalyptus Genotypes Growing under Contrasting Water Availability Conditions
(2024) Elissetche, Juan Pedro; Alzamora, Rosa M.; Espinoza, Yosselin; Emhart, Veronica; Pincheira, Matias; Medina, Alex; Rubilar, Rafael
Limited research exists on wood properties in E. nitens x E. globulus hybrid genotypes grown in water-limited conditions generated by the climate change influence in Mediterranean areas. The EUCAHYDRO project aimed to assess environmental stress impacts on eucalyptus genotypes, including responses to reduced water availability, and to evaluate wood density and resistance using the non-destructive drill resistance technique. This study focused on 10-year-old E. nitens x E. globulus hybrids and Eucalyptus badjensis Beuzev. & Welch, revealing that low irrigation led to a 13% (p < 0.05) decrease in diameter and a 6.5% (p > 0.05) increase in wood density for the hybrids. On the contrary, E. badjensis demonstrated a noteworthy 22% increase in wood density (p < 0.05), while showing a corresponding 0.6% growth increase (p > 0.05), as measured by the diameter at breast height. Drill resistance measurement results indicated that E. nitens x E. globulus' amplitude ranged from 20.1% to 26.6%, while E. badjensis' ranged from 20.8% to 27.2%. The study revealed a high correlation between resistance amplitude and wood density, with coefficients of 0.97 observed for E. nitens x E. globulus and 0.84 for E. badjensis (p < 0.05). These findings fall within the range reported in similar studies involving Eucalyptus spp. The primary focus of the research was to assess the growth potential and wood quality of novel Eucalyptus spp. under conditions of water limitation. The study also explored the utility of drill resistance as a predictive measure for evaluating wood density as an indicator of wood quality.

Browsing by Author "Rubilar, Rafael"

Results Per Page

Sort Options