CHAPTER 5 5 Fagaceae Trees Antoine Kremerl, Manuela Casasoli2,Teresa ~arreneche~,Catherine Bod6n2s1, Paul Sisco4,Thomas ~ubisiak~,Marta Scalfi6, Stefano Leonardi6,Erica ~akker~,Joukje ~uiteveld', Jeanne ~omero-Seversong, Kathiravetpillai Arumuganathanlo, Jeremy ~eror~',Caroline scotti-~aintagne", Guy Roussell, Maria Evangelista Bertocchil, Christian kxerl2,Ilga porth13, Fred ~ebard'~,Catherine clark15, John carlson16, Christophe Plomionl, Hans-Peter Koelewijn8, and Fiorella villani17 UMR Biodiversiti Genes & Communautis, INRA, 69 Route d'Arcachon, 33612 Cestas, France, e-mail: [email protected] Dipartimento di Biologia Vegetale, Universita "La Sapienza", Piazza A. Moro 5,00185 Rome, Italy Unite de Recherche sur les Especes Fruitikres et la Vigne, INRA, 71 Avenue Edouard Bourlaux, 33883 Villenave d'Ornon, France The American Chestnut Foundation, One Oak Plaza, Suite 308 Asheville, NC 28801, USA Southern Institute of Forest Genetics, USDA-Forest Service, 23332 Highway 67, Saucier, MS 39574-9344, USA Dipartimento di Scienze Ambientali, Universitk di Parma, Parco Area delle Scienze 1lIA, 43100 Parma, Italy Department of Ecology and Evolution, University of Chicago, 5801 South Ellis Avenue, Chicago, IL 60637, USA Alterra Wageningen UR, Centre for Ecosystem Studies, P.O. Box 47,6700 AA Wageningen, The Netherlands Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA lo Flow Cytometry and Imaging Core Laboratory, Benaroya Research Institute at Virginia Mason, 1201 Ninth Avenue, Seattle, WA 98101, USA l1 UMR Ecologie des For& de Guyane, INRA, Campus agronomique BP 709, Avenue de France, 97387 Kourou, French Guyana l2 Jodrell Laboratory, Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3DS, UK l3 Austrian Research Centre, 2444 Seibersdorf, Austria l4 The American Chestnut Foundation Research Farms, 14005 Glenbrook Avenue, Meadowview, VA 24361, USA l5 Department of Forestry, North Carolina State University, Box 8008, Raleigh, NC 27695-8008, USA l6 The School of Forest Resources and Huck Institutes for Life Sciences, Pennsylvania State University, 323 Forest Resources Building, University Park, PA 16802, USA l7 Istituto per l'Agroselvicoltura, CNR, V.le G. Marconi, 2 - 05010, Porano, Italy 5.1 forestry, chestnuts are also used for their fruit pro- Introduction duction and have been partially domesticated for that purpose. Castanopsis and Lithocarpus are important ecological components of the Asian flora and have Worldwide, there are more than 1,000 species belong- recently been investigated for their biological diver- ing to the Fagaceae. All Fagaceae species are woody sity (Cannon and Manos 2003). The remaining genera plants and are spread throughout the northern hemi- comprise only a very few species and for the time being sphere, from the tropical to the boreal regions. The have been studied mainly in botany and taxonomy. family comprises seven genera (Govaerts and Frodin Genetic research in Fagaceae has been restricted 1998), and the number of species is extremely vari- to the three genera of economic importance (Cas- able among genera: Castanea (12), Castanopsis (100 tanea, Fagus, and Quercus), although activities in to 200), Chrysolepis (2),Fagus (1 1),Lithocarpus (300), phylogeny and evolutionary genetics have recently Quercus (450 to 600), Trigonobalanus (3). Oaks (Quer- encompassed the whole family (Manos and Stanford cus), chestnuts (Castanea), and beeches (Fagus) are 2001; Manos et al. 2001). Because of their long rota- widely used in forestry for wood products over the tion times, breeding activities in the three main gen- three continents (Asia, Europe, and America) and era have been limited (Kremer et al. 2004). However, are important economic species. Consequently, they population differentiation has been investigated in have received more attention in forest genetic research a very large number of species, with the main aim than other genera. In addition to their cultivation in of identifying geographic patterns or historical foot- Genome Mapping and Molecular Breeding in Plants, Volume 7 Forest Trees C. Kole (Ed.) O Springer-Verlag Berlin Heidelberg 2007 162 A. Kremer et al. prints for molecular markers and phenotypic traits similarity between Quercus, Castanea, Lithocarpus, of forestry relevance. Population genetics has driven and Castanopsis. Paleontological records suggest that most of the research activities in molecular genetics Quercus and Castanea separated 60 million years ago and also genetic mapping, in contrast to other for- (Crepet 1989). Interspecific separation within the gen- est tree species where tree improvement has been the era Quercus, Fagus, and Castanea occurred between main goal. Genetic maps have been constructed in 22 and 3 million years ago as inferred from a molecular at least one species of Quercus, Castanea, and Fagus. clock based on cpDNA divergence (Manos and Stan- Because of their low genetic divergence, it quickly ford 2001). The reduced genetic divergence among the became obvious that molecular markers could be eas- different genera was recently confirmed by the results ily transferred from Quercus to Castanea (and vice obtained in transferring molecular tools and markers versa) but less easily to Fagus. These earlier find- among genera, as it is much more difficult to transfer ings led to further activities on comparative mapping microsatellite markers from Quercus to Fagus than it across genera, especially between Quercus and Cas- is from Quercus to Castanea (Steinkellner et al. 1997; tanea. Barreneche et al. 2004). 5.1.1 5.1.2 Evolutionary Biology and Phylogeny Ploidy, Karyotype, and Genome Size in Fagaceae of the Fagaceae Reported karyotype studies in Quercus, Lithocarpus, Fossil remains indicate that the Fagaceae appeared Castanopsis, and Castanea (Mehra et al. 1972), in at the transition between the secondary and tertiary Quercus (D'Emerico et al. 1995), and Fagus (Ohri era. Remains of Dryophyllum, which is a fossil genus and Ahuja 1991) indicate that the number of chro- belonging to the Fagaceae, were discovered in lay- mosomes within the family is remarkably stable (2n ers belonging to the early Cretaceous (Jones 1986). = 24). Naturally occurring triploids have been men- Fossil remains that were unequivocally assigned to tioned occasionally in oaks (Butorina 1993; Naujoks Fagaceae and dated to the Upper Eocene and Late et al. 1995). Extra chromosomes (2n = 24+1,2 or 3) Oligocene were found in North America (Herendeen have been reported as consequences of irregular seg- et al. 1995) and Europe (Kvacek and Walther 1989). regation in mitoses (Zoldos et al. 1998). Otherwise, C- Differentiation of the various genera occurred dur- banding comparisons have shown that the morphol- ing the mid Tertiary, and reported species of Fagaceae ogy of the chromosomes of Fagus (Ohri and Ahuja at the late Tertiary resemble already extant species. 1991) and Quercus (Ohri and Ahuja 1990) are quite The oldest reported genera belonging to the Fagaceae similar. occurred in Southeast Asia, where the extant species The DNA content is variable across genera in the diversity is also the highest. The family originated Fagaceae: the 2C DNA values varying from a low from Southeast Asia and radiated toward Europe and of 1.11 pg in Fagus to a high of 2.0pg in Quercus America (Wen 1999; Xiang et al. 2000). Migration and species (Table 1). GC content on the other hand ap- major continental rearrangements contributed to dis- pears constant across genera (40%) and is similar junction and vicariance within the family, especially to most higher plants (Table 1). All values reported within Quercus (Manos and Stanford 2001). It is gener- in Table 1 were obtained by flow cytometric analy- ally accepted that most major oak groups essentially sis of interphasic nuclei and are slightly higher than evolved in the areas where they reside today (Axel- earlier assessments made with the Feulgen micro- rod 1983). densitometry method (Ohri and Ahuja 1990). The Phylogenetic investigations based on chloroplast 31 species in Table 1 represent a cross-section of or nuclear DNA data are poorly resolutive, suggest- the Fagaceae across the northern hemisphere. The ing that the differentiation into different genera was two Fagus species, Fagus grandifolia and E sylvat- extremely rapid during the mid Tertiary (Manos and ica, were quite similar in genome size (1.27 and Steele 1997; Manos et al. 2001). All genera are usually 1.11 pg per 2C, respectively) and are at the lower clustered into a "starlike" dendrogram (polytomy), range of genome sizes among the Fagaceae, sug- except Fagus, which diverged earlier from the com- gesting that Fagus has either the most rudimen- mon ancestor. However, there is a strong genomic tary genome or the most greatly reduced genome Chapter 5 Fagaceae Trees 163 Table 1. DNA content in 31 Fagaceae species determined by flow cytometric analysis Species 2C nuclear DNA 1C nuclear DNA GC content Reference pg (mean value) Mbp (%I Genus Castanea C. seguinii Arumuganathan et al.* C. sativa (1) Arumuganathan et al. C. sativa (2) Brown and Siljak-Yakovlev (pers comm) C. crenata Arumuganathan et al. C. mollissima Arumuganathan et al. C. dentata Arumuganathan et al. Genus Fagus F. grandifolia 1.27 610 - Arumuganathan et al. F. sylvatica 1.11 535 40 Gallois et al. 1999 Genus Quercus Subgen Erythrobalanus** Q. velutina Arumuganathan et al. Q. nuttallii Arumuganathan et al. Q. shumardii Arumuganathan et al. Q. nigra Arumuganathan et al. Q. rubra Arumuganathan et al. Q. palustris Arumuganathan et al. Q. coccinea Arumuganathan et d. Q. phellos Arumuganathan et al. Q. falcata Arumuganathan et al. Q. pagoda Arumuganathan et al. Q. imbricaria Arumuganathan et al. Genus Quercus Subgen Lepidobalanus** Q. bicolor 1.35 Arumuganathan et al. Q. montana 1.49 Arumuganathan et al. Q. robur 1.53 Arumuganathan et al. Q. stellata 1.55 Arumuganathan et al. Q. alba 1.59 Arumuganathan et al. Q. macrocarpa 1.62 Arumuganathan et al. Q. robur 1.84 Favre and Brown 1996 Q. pubescens 1.86 Favre and Brown 1996 Q. petraea 1.87 Favre and Brown 1996 Q. robur 1.88 Zoldos et al. 1998 Q.petraea 1.90 Zoldos et al. 1998 Q.