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Stem breakage and forking in low and high elevation Pinus tecunumanii

Scheme R.4346. Oxford Forestry Institute, University of Oxford. Final Report. 136 pp. D vorak , W. S., C. E. B alocchi and R. H. R aymond (1989): Performance and stability of provenances and families of Pinus tecunumanii in the tropics and subtropics. In: Proc. Of an IUFRO conference on Breeding Tropical Trees: Population Structure and Genetic Improvement Strategies in Clonal and seedling forestry. Pattaya, Thailand, 28 November – 3 December, 1988, pp 187–196. D vorak , W. S., C. C. L ambeth and B. L i (1993): Genetic and site effects on stem

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An Evaluation of Selection for Volume Growth in Loblolly Pine

South Carolina piedmont. Forest Research Series No. 7. Clemson University. Clemson, South Carolina. ISIK, F., K. ISIK and S. J. LEE (1999): Genetic variation in Pinus brutia in Turkey: I. Growth, Biomass and Stem Quality Traits. For. Gene. 6: 89-99. LARSON, P. R. (1963): Stem form development of forest trees. Vol. 5. Society of American Foresters. Washington, DC. 42 p. LOEHLE, C. and G. NAMKOONG (1987): Constraints on tree breeding: Growth tradeoffs, growth strategies, and defense investments. For. Sci. 33: 1089

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Genetic control of silvicultural traits in Balfourodendron riedelianum (ENGL.) ENGL.

Abstract

The Atlantic Forest has very high levels of biodiversity and is considered one of the most important and threatened biomes in the world. Balfourodendron riedelianum is one of the forest’s characteristic tree species that is currently under considered endangered due to timber extraction and forest fragmentation. With the goal of generating information that may contribute to the genetic conservation of B. riedelianum, genetic parameters are estimated for quantitative traits important for silviculture in a provenance and progeny test located in the Experimental Station of Luiz Antônio, São Paulo State, Brazil. The test was established in 1986 and consists of three provenances, from which open-pollinated seeds from 19 seed trees were collected. The following traits were evaluated at 32 years of age: diameter at breast height (DBH), total height (H), stem height (SH), stem straightness (SS), and forking (FOR). The estimates were carried out using the REML/BLUP method. Significant genetic variation among progenies was detected for all traits (except SH) and between provenances for DBH. The coefficient of individual genetic variation (CV gi) ranged from 2.5 to 9.5 %. The mean heritability among progeny (hf2) was substantial for DBH (0.44) and FOR (0.36), enabling the selection of families with the highest DBH and lowest FOR for population improvement. Genotypic and phenotypic correlations among traits were also found. We conclude that there is genetic variability in the population that can be exploited in future breeding programs and for the genetic conservation of the species.

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Variance components and parent–offspring cor- relations of growth traits vary among the initial planting spacings in Zelkova serrata

Abstract

Variance components of tree height (HT) and stem diameter at 1.3 m above the ground (DBH) were investigated for the eight open-pollinated families of Zelkova serrata (Thumb.) Makino planted with three different initial planting spacings in a progeny test site, Chiba, Japan. Parent–offspring correlations were also evaluated by using these families and their mother trees. The smallest values of HT and DBH were observed in the narrowest initial planting spacing (1.10 x 1.10 m) compared to those in medium (1.30 x 1.36 m) and wide (2.00 x 1.80 m) spacings, suggesting that adverse effects of competition with neighboring trees occurred on both height and radial growth. Similar to HT and DBH, the initial planting spacings also affected the genetic parameter estimates: the ratio of family variance component to total phenotypic variance showed the highest value in narrow initial planting spacing for both HT and DBH. Thus, family variance component might include competition effects, leading to biased genetic parameter estimates. In contrast, parent–offspring correlation coefficients showed the highest value in wide initial planting spacing where competition effect might be smaller. Therefore, the growth traits of Z. serrata might be inherited from the parent to the offspring when competition effect was small.

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Forward, backward selection and variation analysis of growth traits in half-sib Larix kaempferi families

, Wolliams JA, Kanowski PJ, Bridgwater FE (2001) Interactions of geno­type with site for height and stem straightness in Pinus taeda in Zimbabwe. Silvae Genet 50:135-140 Haapanen M (2001) Time trends in genetic parameter estimates and selection efficiency for Scots pine in relation to field testing method. Forest Genetics 8: 129-144 Hannrup B, Elberg I, Persson A (2000) Genetic correlations among wood, growth capacity and stem traits in Pinus sylvetris. Scand. J. For. Res 15: 161-170 https://doi.org/10

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Impact of fertility variation on genetic diversity and phenotypic traits in second generation seed production areas and clonal seed orchards of Eucalyptus camaldulensis

for a seedling seed orchard design based on trait selection index and genomic analysis by molecular markers: a case study for Eucalyptus dunnii. Tree Physiol 25:1457–1467. https://doi.org/10.1093/treephys/25.11.1457 Zhu Y, Wu S, Xu J, Lu Z, Li G, Hu Y, Yang X, Bush D (2017) Genetic parameters for growth traits and stem-straightness in Eucalyptus urophylla x E. camaldulensis hybrids from a reciprocal mating design. Euphytica (2017) 213:142. https://doi.org/10.1007/s10681-017-1923-3

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Density and wood biomass development in whole-tree analyses of Scots pine, and aspects on heritability estimates

-felling. For. Ecol. Manage. 177 : 65–74. E liasson , N. (2003): Effects of pre-commercial thinning time and stem density on the amount of juvenile wood in Scots pine. Swedish University of Agricultural Sciences, Department of Silviculture, Umeå, Sweden, Examensarbeten 2003:10, MSc-thesis. F ries , A. and T. E ricsson (2006): Estimating genetic parameters for wood density of Scots pine ( Pinus sylvestris L.). Silvae Genet. 55 : 84–92. F ries , A. and T. E ricsson (2009): Genetic parameters for earlywood and latewood densities and development by

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Low Cost Improvement of Coastal Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) By Application of The Breeding Seed Orchard Approach in Denmark

. LINDGREN (1998): Predicting Genetic Gain of Backward and Forward Selection in Forest Tree Breeding. Silvae Genet. 47: 42-50. SAS Inst. Inc. (1999): SAS OnlineDoc® version eight, SAS Institute Inc., Cary, NC, USA, http://v8doc.sas.com/sashtml. SCHERMANN, N., W. T. ADAMS, S. N. AITKEN and J. CH. BASTIEN (1997): Genetic Parameters of Stem Form Traits in a 9-Year-Old Coastal Douglas-fir Progeny Test in Washington. Silvae Genet. 46: 166-170. SILEN R. R., D. L. OLSON and J. C. WEBER (1993): Genetic variation in susceptibility to

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Variation and Correlations Among Stem Growth and Wood Traits of Calycophyllum spruceanum Benth. from the Peruvian Amazon

, Lima, Peru. 73 p. SOTELO MONTES, C., H. VIDAURRE and J. C. WEBER (2003): Variation in stem-growth and branch-wood traits among provenances of Calycophyllum spruceanum Benth. from the Peruvian Amazon. New Forests 26: 1-16. STEARNS, S. C. (1989): The evolutionary significance of phenotypic plasticity. Biological Science 39: 436-45. STERN, R. D., R. COE, E. F. ALLAN and I. C. DALE (Eds.) (2004): Good Statistical Practice for Natural Resources Research. CABI Publishing, CAB International, Wallingford, U.K. 388 p

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Resistance of Castanea Clones to Phytophthora Cinnamomi: Testing and Genetic Control

. CRANE and F. C. S. TAY (1994): Invasion of Phloem and Xylem of Woody Stems and Roots of Eucalyptus marginata and Pinus radiata by Phytophthora cinnamomi. Phytophatology 84 (4): 335-340. DIXON, K.W. and K. THINLAY SIVASITHAMPARAM (1984): Technique for rapid assessment of tolerance of Banksia spp. to root rot caused by Phytophthora cinnamomi. Plant Disease 68, 1077-80. EGEL, D. S. (1999): Preventing seedling diseases in the greenhouse. Purdue University Cooperative Extensio service. http

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