Single-tree Plots Research Articles

Early selection efficiency in a progeny test of timber species Cordia trichotoma (Vell.) Arráb. ex Steud

One of the key obstacles in forest breeding routines is the time-consuming steps of selection and recombination of superior genotypes owing to the long life cycle of trees. Considering the increase in global temperature and constant climate alterations, the quick selection of genetic materials is crucial to ensure the effectiveness of genetic improvement programs. Early selection studies on other forest species are scarce, barring eucalyptus and pine, which are well-studied crops. In this context, this study aimed to understand the efficiency of early selection in a progeny test of Cordia trichotoma (Vell.) Arráb. ex Steud to evaluate age-age trends, genetic variability, and potential gains. A progeny test was conducted and measured at three, six, and eight years of age for growth traits, diameter, and volume increment. The experiment included 21 open-pollinated families of C. trichotoma arranged in a 4 × 4 m experimental design grid with a single-tree plot distributed into 10 blocks. The genetic correlations among the three measurements for genitor selection were greater than 0.90 for all the traits. For every ten progenies selected at three years of age, approximately seven were determined to be similarly top-ranked at eight years of age, taking into account an early selection assertiveness rate of approximately 0.70 for progenies. Considering the high age-age genetic correlation found in the C. trichotoma progeny test, there is a significant possibility of improving genetic gains per unit of time through early selection. The general mean of volume increment was 18 m3 ha−1 year−1, with productive genotypes showing a volume greater than 30 m3 ha−1 year−1 and representing an estimated general gain of 66 %. Superior genotypes of C. trichotoma are highly competitive in terms of volumetric yield, can generate considerable gains, and are used in the forest industry. Early selection of C. trichotoma is efficient, with a high rate of assertiveness.

Would it be possible to reduce the number of repetitions in the evaluation of clones in a single tree plot?

Would it be possible to reduce the number of repetitions in the evaluation of clones in a single tree plot?

The Environmental and Genetic Controls of Increment Suggest a Limited Adaptability of Native Populations of Norway Spruce to Weather Extremes

In the Baltics, warming is expected to burden the growth of Norway spruce Picea abies, with weather anomalies/extremes having strong triggering effects, which can be mitigated by tree breeding. Within the region, breeding programmes have been aiming for productivity, yet being conservative, their sustainability depends on the adaptability of native genotypes, which is unclear. The adaptability of genotypes can be assessed through local adaptations and phenotypic plasticity, with the sensitivity of increment depicting the conformity of genotypes and environments. To assess the adaptability of native populations to anticipated climates, local genetic adaptation and phenotypic plasticity of the weather sensitivity of the radial increment were assessed by the methods of time series analysis and quantitative genetics based on three clonal trials (low-density single-tree plot plantations of grafted clones of native plus trees) representing the local climatic gradient in Latvia. The growth of trees was sensitive to the moisture availability in summer and the thermal regime in winter, yet coinciding anomalies in both were associated with abrupt changes in tree ring width. These environmental effects differed among the clones, indicating genetic controls over the sensitivity of increment, which, however, decreased under a warmer climate, suggesting a limited adaptability of local populations to warming. Still, the weather-growth relationships showed moderate phenotypic plasticity, suggesting some mid-term adaptability. Accordingly, supplementation of breeding populations via assisted gene transfer with the genotypes that are adapted to warmer and drier climates appears crucial.

Multi-site comparison of clonal arrangements for tropical and subtropical hybrids of Eucalyptus

The definition of the ideal eucalyptus clonal arrangement directly affects the forest industrial chain, quality of products, and stand yield. The impact of eucalyptus in mono- versus multiclonal stands on plantation production and sustainability has been frequently discussed by primary stakeholders within the pulp industry, but few studies have examined this topic through direct comparison. In this study, we evaluated the differences in genotype ranking and yield of Eucalyptus spp. and clones displayed in mono- and multiclonal arrangements. In this context, the objectives addressed were: (i) to estimate genetic parameters in multi-environment and site-by-site analyses; (ii) to predict genotypic values of clones and the effects of species in mono- and multiclonal experiments, and (iii) to compare the similarity between the ranks of clones and species in the two types of clonal stands. The study was conducted in 2018 at four different sites of the CMPC Celulose Riograndense company, located in the state of Rio Grande do Sul, Brazil. Mono- and multiclonal arrangements were tested at each site, involving 33 eucalyptus clones belonging to 10 species and hybrids. Multiple-tree-plot (MTP) and single-tree-plot (STP) experiments were used to simulate monoclonal stands and multiclonal or composite stands, respectively. In each experiment, a randomized block design was set with three repetitions, 16 plants per plot for MTP, and 24 repetitions and one plant per plot for STP. Traits monitored were diameter at breast height (DBH), total height (H), tree volume (VOL), mean annual volume increment (MAI), and survival (SUV). Data were analyzed using mixed model approaches, considering a normal distribution for growth traits and a binomial family for survival. There was a strong genotype × site interaction for all traits, indicating that edaphoclimatic conditions must be considered for the successful establishment of clonal composites of differing genotypes. There was high similarity in the classification of clones in both mono- and multiclonal experiments, with genetic correlation values above 0.90. The performance of clones differed in mono- and multiclonal experiments, which correlated with their competition behavior toward each other (aggressive, suppressed, or homeostatic). Thus, clonal composites can be recommended based on clonal competition and genetic heterogeneity to maximize the yield of the stand and safeguard the plantations from biotic and abiotic disturbances. This study allowed us to identify the differences between the two types of commercial stands and provide direction for future research regarding the performance of Eucalyptus spp. in differing clonal arrangements. Novel information about competition categories for different eucalyptus tropical and subtropical species were provided.

Genetic Parameter Estimates from a Polymix Breeding Population of Pinus taeda L.

Abstract Estimation of genetic parameters from progeny testing is essential for many important decisions in forest tree breeding. In this study, we estimated heritabilities, trait-trait genetic correlations, and genotype by environment (GxE) interactions using a large multi-environmental data set of Pinus taeda L. in the southern United States. In the study, 284 parents were pollinated with a pollen mix and were field tested in four different test series. A total of twenty tests (two to seven tests per series) were established using randomized complete block design with single tree plots. Half-sib family-mean heritability estimates within individual test series varied considerably for all the traits. Pooled estimates of half-sib family-mean heritability estimates across series were 0.81 for fusiform rust incidence; they were relatively lower for tree height (0.68), diameter at breast height (DBH; 0.66), and stem straightness (0.58). Genetic correlations between pairs of traits were low except for height and diameter, which had a high genetic correlation (0.79). Additive genetic correlations between pairs of sites within test series (as a measure of GxE) varied. The pooled estimates ranged between 0.65 (DBH) to 0.80 (fusiform rust). The results suggest that polymix mating is efficient for parental selection in Pinus taeda L. and for deployment in the seed orchards. Study Implications: This study focused on genetic variation in the Piedmont breeding population of Pinus taeda L. in the United States. The Piedmont population was developed for more inland and colder regions of the species. Fusiform rust disease incidence of pine species of southeastern United States is a major threat to pine plantations. Understanding the level of genetic control on disease outcome is vital to develop sound breeding strategies and recommend deployment practices to mitigate the economic loss of landowners. The results provide valuable information to breeders to select disease-resistant genotypes to breed and put into seed orchards to mass-produce stock for planting.

Performance Based on Measurements from Individual-Tree Progeny Tests Strongly Predicts Early Stand Yield in Loblolly Pine

Abstract To facilitate the utility of genetic improvement in loblolly pine, individual-tree volume (productivity) scores estimated from single-tree plot or row-plot progeny test designs were compared with stand-level volume per unit area from block plots. A large number of families representing a wide range of progeny test scores for volume were established in growth and yield trials to generalize the results to families created by the breeding program. Individual-tree volume scores from progeny tests strongly corresponded with stand-level volume from block plots, especially after accounting for site quality and the risk of fusiform rust disease. A ten-point increase in the volume score from progeny test data was estimated to increase stand-level volume by 3.9 m3 ha-1 at age 6 years. A prediction model is presented that includes a new statistic, rust risk index, which is the expected rust incidence for a family at a new site when the hazard of rust for a checklot can be estimated from historical data. The study results through age 6 years corroborate the Performance Rating System as effective in guiding family deployment decisions. The models presented are based on pre-crown closure data at 6 years and will be updated with older measurements as the study matures. Study Implications: The Performance Rating System (PRS™) has been a successful tool for presenting genetic merit of improved loblolly pine families for landowners and forest managers in a more coherent and standardized manner. This system can be easily applied in other forest tree improvement programs, because it makes genetic improvement user-friendly for silviculturists and forest managers. Landowners can use this system to make decisions for selecting improved families suited to their specific forest management objectives. Seed orchard and nursery managers also depend on the PRS to choose the families to produce and as a third-party verification to market their genetic merit to customers. This study demonstrates that higher stand-level volume per unit area can be achieved when forest managers plant fast growing families with low fusiform rust disease risk on productive sites. The combined effect of genetic improvement for productivity and fusiform rust disease resistance is significant on stand-level volume per unit area.

RESISTÊNCIA DO SOLO E ANÁLISES MULTIVARIADAS COMO UM MÉTODO A UXILIAR PARA A SELEÇÃO DE PROGÊNIES DE Calophyllum brasiliense

ABSTRACT Precision silviculture is being developed to manage and improve Calophyllum brasiliense, a tree species associated with wet and swampy soils. This study estimated genetic parameters for growth traits in response to soil resistance as an auxiliary tool for identifying and selecting progenies adapted to water-saturated soils. This was undertaken in a progeny test of C. brasiliense in which 1,200 seedlings grown from seeds collected from a natural population were planted in a randomized complete block design for single-tree plots. Genetic statistical analysis was conducted using the REML/BLUP method. Significant differences (p<0.01) in diameter at breast height were observed among the progenies. The coefficients of genetic variation and heritability at the individual and progeny levels were low for diameter at breast height and height, indicating low genetic control for these traits, while high positive and significant genetic and phenotypic correlations were detected between diameter at breast height and height. Theoretical genetic gains and multivariate statistical analysis indicated three groups of progenies with different degrees of tolerance and adaptability to flooded soils, which could be useful in future breeding programs for this species, although further analysis at advanced ages is still required. The mean heights of tolerant and sensitive progenies were 12 and 58%, respectively, lower than the theoretical values, indicating that constant soil flooding is harmful to this species.

Strategies for the analysis of single-tree plot experiments in Eucalyptus plantations

To verify if the response by Eucalyptus clones in a single-tree plot is influenced by neighboring plants and to determine the effect of missing and/or dominated plants, seven eucalyptus trials in four Brazilian states were analyzed in a randomized complete block design with one plant/plot and 30 replications. Mean annual increment (MAI, m3 ha−1 per year) was determined for three-year-old clones. The influence of neighboring clones was estimated by a linear regression coefficient between the MAI of each clone/plot and the average of a clonal MAI and its eight neighbors. To determine the effect of missing and/or dominated trees, a correction between the MAI and the area available/plant was applied. Subsequent analysis considered unadjusted and adjusted data for missing and dominated trees. Estimate of accuracy and index of coincidence were used to compare the adjustments. In single-tree plots, clone performances were not influenced by neighboring plants. Experimental accuracy was not increased by any of the adjustments employed and the clone ranking was not altered, and therefore did not justify their use.

ACCURACY OF GENETIC PARAMETERS ESTIMATION AND PREDICTION OF GENOTYPIC VALUES IN EUCALYPTUS USING DIFFERENT PLOT TYPES

A suitable experimental design should control the environmental effect and be capable of discriminating genotypes. Two clonal tests of Eucalyptus were planted side by side in a randomized block design with the same 32 treatments under two different plot designs. The first trial was designed with five plants per plot (linear plot, LP) and six block replicates at a spacing of 3 x 2 m. The second trial was designed with one plant per plot (single-tree plot, STP) and 30 block replicates also at a spacing of 3 x 2 m. Diameter at breast height (dbh), height (h), and individual volume (vol) were measured at five years of age. The STP design presented broad-sense heritabilities values of 0.23 for h and 0.41 for vol, which were higher than those found for the LP design (0.12 for h and 0.22 for vol). The ratio between the standard error and the estimated genotypic variance (Sg^ ) was lower for the three evaluated traits in the STP trial. The correlations between the genetic values were positive and of high magnitude, ranging from 0.87 (h) to 0.91 (vol), but there were many differences between the two designs with regard to the ranking of clones. The STP presented better discriminant power according to the biplot analysis, as well as more accurate and reliable estimates.

Trends of genetic parameters and stand volume productivity of selected clones of Eucalyptus pellita observed in clonal trials in Wonogiri, Central Java

Breeding program of Eucalyptus pellita has proceeded into advanced generationswith clonal development as best way to deliver greater genetic gain. Clonal test is a prerequisite for selecting and verifying the clones productivity before deployment. Following the breeding strategy, clonal trials of E. pellita were established in Wonogiri, CentralJava. The purposes of this study are to observe trends of genetic parameters and stand volume productivity of clones tested in clonal trials of E. pellita. The trials were laid out in two experimental designs: 1) nine clones, 16 replications, single tree-plot, spacing 3 x 2m;2) 4 clones, 2-4 replications, 16 squares tree-plot, spacing 3 x 2m. Each trial also contains control (i.eseedling material). Measurements were conducted five times from six monthsto 46 months age. Results showed that trends of growth increased along the measurements with nine tested clones performed better than control seedlings. The growths were significantly different among clones along the ages with clone repeatibility ranging from 0.49 to 0.98.Three selected clones namely clone 1,2 and 3on the basis of height growth and multiplication rates showed higher stand volume productivity compared to control and consistently increased on average of0.37 m3/ha at 6 months to 73.93 m3/ha at 46 months age.

Tree breeding and silviculture: Douglas-fir volume gains with minimal wood quality loss under variable planting densities

Validating performance of genetically-selected trees under realistic planting scenarios is essential for confidence in tree breeding programs. Quantifying the relative impact of genetic selection and initial planting density on tree size and quality can further guide operational forest practices. We evaluate volume gains, survival, stem quality and wood quality traits on 20-year old trees representing three levels of genetic selection that were grown under four initial planting densities. Working in a realized gain trial for coastal Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) on five replicated sites, we ask: (1) Do predicted stand productivity levels materialize as expected under different planting densities? (2) Are single-tree plot designs, simulating progeny trials, capable of producing reliable results relative to large-block designs, simulating realistic planting scenarios? (3) If trees selected for volume gain show declines in wood and stem quality relative to wild-stand controls, can this be effectively managed by altering stocking densities? Because young progeny trials are used to estimate genetic gain in tree volume at a rotation age of 60, we use a growth and yield model calibrated to wild-stand controls to assess whether genetically-selected families meet projections at age 20. On average, observed stand volumes exceeded projections on four out of five sites, and in three out of four initial planting densities. At the level of site by planting density, the moderate genetic-gain population (mid-gain) exceeded projections 13 out of 20 times while the top genetic-gain population (top-crosses) exceeded projections 11 out of 20 times. This fits expectations for breeding values, which are designed to reflect general performance averaged across all environments. Using a different validation approach, large-block designs showed better performance relative to simulated progeny trial designs. Very high planting densities (1890+ stems/ha) may minimize wood quality losses of genetically-selected planting stock but effects are relatively minor, while good performance among all traits was observed at operational planting densities (~1189 stems/ha). Wood density and microfibril angle proxy measures in top-crosses showed relatively minor and non-significant losses (−1.1 to −4.0%) compared to major and significant gains in volume per hectare at age 20 (29.0%) when averaging values at 1189 and 1890 stems/ha. Altogether, the genetic selection systems produce reliable results across a range of site qualities.

Evaluation of genetic parameters and clonal selection of Eucalyptus in the Cerrado region

Eucalyptus plantations in Brazil are expanding toward the northern and mid-western regions of the country. The objective of the present study was to select clones adapted to the local conditions, with a focus on the Cerrado region. Three clonal experiments were conducted in the municipalities of Catalão, Corumbá-de-Goiás, and Luziânia, in Goiás State, with 109 genotypes of eucalypts. The experimental design consisted of a randomized complete block design with single-tree plots and 29 blocks. Diameter at breast height and total height of all trees were measured four years after planting, for use in the estimation of wood volume for each genotype. The genotype × environmental interaction was significant and predominantly (74%) complex. The genotypic correlation among environments was moderate (< 0.47), indicating that clones should be selected for specific sites. However, some clones performed relatively well across all environments, such as clones CCL21, CCL30, AEC144, CCL07, and CCL35.

Variation in seed and seedling traits of &lt;i&gt;Faidherbia albida&lt;/i&gt; (DEL.) A. Chev populations in the Sudano-Sahelian zone of Cameroon

The once sustainable agroforestry system in the Sudano-Sahelian zone of Cameroon has been abandoned and trees overexploited. A study on the variability in seed and seedling traits of Faidherbia albida (DEL.) A. Chev populations from different climatic zones was carried out. Six populations were selected from Sudanian (Poli, Garoua III, and Figuil) and Sahelian (Yagoua, Moulvoudaye and Maroua I) climatic zones and harvested seeds were transported to the experimental farm of IRAD Yagoua for pretreatment and growth experiment. Four pretreatments (98% sulfuric acid, hot water, scarification and soaking in water for 24 hours) were used to initiate the germination. After one month, the rate of germination (%) was recorded and seedlings were transplanted in three substrates for seedling growth evaluation. Growth traits (Survival, plant height, root collar diameter, number of leaves, root length, plant fresh weight and plant dry weight) were measured after three months. The experimental design was a single tree plot randomized complete block design with 30 blocks. Results indicated there was significant difference (p = 0.002) among pre-treatments for the germination. The highest rate of germination was recorded with seedlings from scarified seeds (78.33%), followed by those from seeds treated with sulfuric acid (76.67%). Seeds and seedling traits were significant among populations with Yagoua recording the highest in most of the traits measured. Scarification can assist in seed germination and movement of seeds between populations and climatic zones should be considered during conservation programs.© 2019 International Formulae Group. All rights reserved.Keywords: Faidherbia albida, agroforestry parklands, seed pretreatments, seedling traits, conservation, Sudano-Sahelian, Cameroon

Comparison of genetic parameters between optimal and marginal populations of oriental sweet gum on adaptive traits

Genetic parameters of 9 oriental sweetgum (Liquidambar orientalis Mill.) populations were estimated at a common garden test. Open-pollinated seeds were collected from 16-27 families for each population. The common garden test was established in 2009 using a randomized complete block design in 25 blocks with single tree plot, with each block included 223 families. Breast height diameter, height and crown diameter were measured at the age of five. The purpose of study was to compare the genetic parameters of optimal and marginal populations and to assess the findings for genetic conservation. The study revealed significant variability in all traits evaluated. In variance components, variation among populations was three times higher than that of families. Individual heritability estimates for breast height diameter, height and crown diameter pooled across the whole dataset (marginal and optimal populations) were 0.21 ± 0.04, 0.27 ± 0.04 and 0.11 ± 0.03 and additive genetic coefficients of variation were 13.4%, 9.1% and 7.1%, respectively. Individual heritability estimates for breast height diameter, height and crown diameter in marginal and optimal populations were 0.27 ± 0.10, 0.19 ± 0.08 and 019 ± 0.08 and 0.19 ± 0.04, 0.29 ± 0.05 and 0.09 ± 0.03, respectively. Additive genetic coefficients of variation for breast height diameter, height and crown diameter were 16.7%, 8.3% and 10.8% in marginal and 12.8%, 9.1% and 6.2% in optimal populations, respectively. While breast height diameter and crown diameter were more heritable for marginal populations, height was more heritable for optimal populations. These findings are discussed in terms of genetic conservation of oriental sweet gum.

Statistical strategies design based on competition classes of Eucalyptus clones

A detailed knowledge of different types of trial designs is essential to establish adequate Eucalyptus breeding strategies. This study compared clone’s development in single-tree-plot (STP) and square-plot (SP) experiments to analyze differences in estimated genetic parameters, ranking, predicted genotypic value and competition ability. Experiments were carried out in the CMPC Celulose Riograndense Company, in the state of Rio Grande do Sul, Brazil. A total of 239 clones were used, 214 of which were common to the STP and SP trials. Results showed that STP is a very promising trial design for accurately ranking the genotypes. The STP and SP tests showed high coincidence in ranking selection, but the best clone yields were overestimated in the STP trial and the yields of the worst clones were underestimated in the STP trial. Therefore, an STP design should be used in initial and intermediary clonal tests, and an SP design should be used in the final stages of a breeding program, in order to estimate the clonal yield at a semi-operational scale. The estimated yield decreasing of clones planted in SP compared to STP is 26%. This value should be used in future STP experiments in the same area and with the same germplasm evaluated in this work. In addition, this research identified classes of aggressive clones, sensitive clones, and clones that were homeostatic to the competitiveness effect. Based on this classification, the optimized multiclonal plantation were suggested aiming to maximize yield by using aggressive and homeostatic clones.

Evaluation of different selection indices combining Pilodyn penetration and growth performance in Eucalyptus clones

Abstract: The present study aimed to evaluate the selection indices efficiency for Pilodyn penetration combined with growth traits in Eucalyptus clones. It was carried out experiments in a randomized block design, with single tree plots and 30 replications. Diameter at breast height (DBH), total height (TH), and Pilodyn penetration as an indicator of basic density (BD) were measured. The volume was estimated. Based on predicted genotypic values, three indices presented the highest accuracies: I 8 (based on partial correlation), I 7 (based on the concept of multivariate BLUP) and I 3 (based on two variables as ratio, which uses a third heritability estimate associated to the ratio DBH/BD, besides the two heritabilities of DBH and BD). Thus, it is possible to optimize the selection by combining properly the variables using their genetic control, precision and the relationships between them. The best options came from using only two no redundant traits DBH and BD. Key words : Selection criteria, accuracy, wood quality, partial correlation, path analysis.

&lt;b&gt;Genetic variability and progeny selection of peach palm via mixed models (REML / BLUP)

Heart of palm harvesting and exploitation has reduced the natural reserves of acai and jucara; hence, the peach palm is an excellent option as source of heart of palm that can reduce the pressure on these two species. The peach palm has high tillering and no post-harvest oxidation. An experiment in a randomized block design with 72 progenies of peach palm, 36 replications and a single tree plot was performed for five years at the experimental field of Embrapa in the Western Amazon. Genetic parameters were estimated using two mixed models, one based on progeny means and the second on joint information from crops. A repeatability analysis, genotype selection, and progeny selection were performed; the Mulamba and Mock selection index was determined; and Tocher’s clustering method was applied. The repeatability analysis revealed the existence of genetic variability, low repeatability, which ranged from 0.3307 to 0.6698 for five years. The analysis performed through the progeny means showed a heritability that varied from 51% to 23% for in all variables; the clustering revealed two groups. The progeny selection should be the main selection strategy, and crosses of superior progenies of different groups should be emphasized.

Early Growth and Stand Volume Productivity of Selected Clones of Eucalyptus pellita

Using current technologies, several forest plantation companies in Indonesia are pursuing clonal forestry program with E. pellita to increase plantation productivity using selected clones. This paper evaluates the early growth and stand volume productivity of selected clones of E. pellita as part of a breeding program for pulpwood. Two clonal trials of E. pellita were established in Central Java with two different plot configurations: single tree-plot and multiple tree-plot. Trial evaluation was done at two years age involving tree height, diameter, stem volume and stand volume. Result show that among the clones there were significant differences for all traits assessed. All of the tested clones exceeded the control seedling of F-1 generation by 9-50% for height, 10-36% for diameter and 22-137% for stem volume, respectively. Clonal repeatability ranged from 0.7-0.9, with corresponding individual ramet repeatability ranged from 0.2-0.4. Overall stand volume productivity at given age reached 15 m³/ha.

Drosophila suzukiiControl in Tart Cherries, 2015: Table 1

This trial evaluated the efficacy of three weekly applications of 19 insecticides in cherry against Drosophila suzukii , commonly referred to as spotted wing drosophila (SWD). Single tree plots were established in a 20-year-old ‘Montmorency’ tart cherry planting (15 × 20 ft spacing) at the Trevor Nichols Research Center in Fennville, MI. Treatments were organized into an …

Nutrient use efficiency in interspecific hybrids of eucalypt

The aim of this work was to evaluate nutrient use efficiency in interspecific hybrids of eucalypt, as an aid in the development of forest breeding programs for areas with limited nutrients. To do this, five clones were evaluated at 2.25 years of age from hybrids resulting from crosses of Eucalyptus grandis x E. urophylla (C1, C2, C3, C4 and C5). The experimental design was of randomised blocks, with single-tree plots and 35 replications. For the study, four trees of average performance were cut down (replications) from each treatment (clone); the biomass, and content and efficiency of use of N, P, K, Ca and Mg were determined in the wood, bark, leaves and branches. The data were submitted to analysis of variance and the F-test, and the means compared by Tukey's test at 5% probability. It was found that the average for biomass allocation was greater (66.2%) for the wood, followed by the branches (13.2%), leaves (11.0%) and bark (9.6%). The C2 and C5 clones stood out as the most efficient in the use of P, Ca and Mg in the wood. The use of genotypes which are efficient in the use of nutrients is essential to the sustainability of forest ecosystems, reducing nutrient export in proportion to the biomass produced. Also, the recommendation of genotypes which are efficient in the use of nutrients for sites of poor soil fertility can optimise productivity in these locations.