Author
Abstract
Cedrela odorata is a tree of utmost importance. Thus a progeny trial was established in Veracruz, Mexico, with 168 families from 19 provenances of southeast Mexico. Significant differences among provenances and families were found at 3, 5, 7 and 11 years of age for height, diameter at breast height [dbh] and volume, and stem straightness and branch thickness at 11 years of age. Individual heritability ($\left( {{h^2}_i} \right)$) fluctuated between years from 0.16 to 0.29, improving with age. For straightness and branch thickness, ${h^2}_i$ = 0.12 and 0.10 respectively. Growth traits showed a genetic correlation (rg ≥ 0.99) among them. Genetic correlation (rg) of straightness with height, dbh, volume and branch thickness were -0.24, -0.13, -0.18 and 0.56 respectively, and rg of branch thickness with height, dbh and volume were 0.04, 0.11 and 0.13 respectively. Age-age genetic correlations were ≥ 0.93 for growth traits. A 56% gain in volume was obtained by using this variable as the selection criterion, leaving 20% of the best trees standing. Early selection at three years old, based on dbh was efficient to improve volume at 11 years with 37.3% gain, whereas at seven years the volume gain was 54%. None of the options dramatically altered form variables.
For further details log on website :
https://www.jstor.org/stable/43956811?Search=yes&resultItemClick=true&&searchUri=%2Ftopic%2Ftropical-forests%2F%3Frefreqid%3Dexcelsior%253A52d8b8c4a68e793d4e54a689dcae7465
E Hernández-Máximo, J López-Upton, V Sánchez-Monsalvo, JJ Vargas-Hernández and JG Salazar-García
Journal of Tropical Forest Science
Vol. 28, No. 4 (October 2016), pp. 446-456
Published by: Forest Research Institute Malaysia
Stable URL: http://www.jstor.org/stable/43956811
Page Count: 11
Abstract
Cedrela odorata is a tree of utmost importance. Thus a progeny trial was established in Veracruz, Mexico, with 168 families from 19 provenances of southeast Mexico. Significant differences among provenances and families were found at 3, 5, 7 and 11 years of age for height, diameter at breast height [dbh] and volume, and stem straightness and branch thickness at 11 years of age. Individual heritability ($\left( {{h^2}_i} \right)$) fluctuated between years from 0.16 to 0.29, improving with age. For straightness and branch thickness, ${h^2}_i$ = 0.12 and 0.10 respectively. Growth traits showed a genetic correlation (rg ≥ 0.99) among them. Genetic correlation (rg) of straightness with height, dbh, volume and branch thickness were -0.24, -0.13, -0.18 and 0.56 respectively, and rg of branch thickness with height, dbh and volume were 0.04, 0.11 and 0.13 respectively. Age-age genetic correlations were ≥ 0.93 for growth traits. A 56% gain in volume was obtained by using this variable as the selection criterion, leaving 20% of the best trees standing. Early selection at three years old, based on dbh was efficient to improve volume at 11 years with 37.3% gain, whereas at seven years the volume gain was 54%. None of the options dramatically altered form variables.
For further details log on website :
https://www.jstor.org/stable/43956811?Search=yes&resultItemClick=true&&searchUri=%2Ftopic%2Ftropical-forests%2F%3Frefreqid%3Dexcelsior%253A52d8b8c4a68e793d4e54a689dcae7465
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