<abstract xmlns="http://www.w3.org/1999/xhtml"><p> Ceratocystis wilt, caused by Ceratocystis fimbriata, is one of the most damaging diseases in eucalyptus plantations worldwide. Although there are resistant genotypes, the genetic basis of resistance is still poorly understood. In this paper we studied the resistance level by a stem inoculation experiment of genotypes of Eucalyptus grandis and E. urophylla and estimated the heritability and gains of selection in families derived from controlled interspecific crosses. In both species, highly resistant as well as highly susceptible genotypes to Ceratocystis wilt were found. Out of 21 parents assessed, twelve were resistant and nine susceptible. Estimates of individual narrow (50%) and broad (59%) sense heritability suggested a high degree of genetic control and low allelic dominance of the trait. There was great genetic variation among and within families, a fact that contributes to high heritability and genetic gain. A genetic gain in lesion size of up to -74.4% was obtained from selection of the 50 best clones in the evaluated families, i.e., the mean lesion length in the progeny population can be reduced by 74,4%.</p></abstract>

Ceratocystis wilt, caused by Ceratocystis fimbriata, is one of the most damaging diseases in eucalyptus plantations worldwide. Although there are resistant genotypes, the genetic basis of resistance is still poorly understood. In this paper we studied the resistance level by a stem inoculation experiment of genotypes of Eucalyptus grandis and E. urophylla and estimated the heritability and gains of selection in families derived from controlled interspecific crosses. In both species, highly resistant as well as highly susceptible genotypes to Ceratocystis wilt were found. Out of 21 parents assessed, twelve were resistant and nine susceptible. Estimates of individual narrow (50%) and broad (59%) sense heritability suggested a high degree of genetic control and low allelic dominance of the trait. There was great genetic variation among and within families, a fact that contributes to high heritability and genetic gain. A genetic gain in lesion size of up to -74.4% was obtained from selection of the 50 best clones in the evaluated families, i.e., the mean lesion length in the progeny population can be reduced by 74,4%.

Resistance to Ceratocystis Wilt (Ceratocystis fimbriata) in Parents and Progenies of Eucalyptus grandis x E. urophylla

Silvae Genetica

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Ceratocystis wilt, caused by Ceratocystis fimbriata, is one of the most damaging diseases in eucalyptus plantations worldwide. Although there are resistant...

Resistance to Ceratocystis Wilt (Ceratocystis fimbriata) in Parents and Progenies of Eucalyptus grandis x E. urophylla

Pubblicato online: 20 ott 2017

Pagine: 99 - 106

Ricevuto: 08 mag 2010

DOI: https://doi.org/10.1515/sg-2010-0012

Parole chiave
Genetic parameters, genetic resistance, forest pathology

© 2017

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Resistance to Ceratocystis Wilt (Ceratocystis fimbriata) in Parents and Progenies of Eucalyptus grandis x E. urophylla

Pubblicato online: 20 ott 2017

Pagine: 99 - 106

Ricevuto: 08 mag 2010

DOI: https://doi.org/10.1515/sg-2010-0012

Parole chiaveGenetic parameters, genetic resistance, forest pathology

© 2017

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Parole chiave
Genetic parameters, genetic resistance, forest pathology