naa a22 4500 510730639 CHVBK 20180411082951.0 cr unu---uuuuu 180411e20130601xx s 000 0 eng 10.1007/s11295-013-0593-0 doi (NATIONALLICENCE)springer-10.1007/s11295-013-0593-0 A comparison of the effect of genetic improvement, seed source and seedling seed orchard variables on progeny growth in Eucalyptus nitens in South Africa [Elektronische Daten] [Tammy-L. Swain, Steve Verryn, Mark Laing] Eucalyptus nitens is an important forestry species grown for pulp and paper production in the temperate, summer-rainfall regions of South Africa. A tree improvement programme has been ongoing at the Institute for Commercial Forestry Research for two decades, but genetic improvement in the species has been slow due to delayed and infrequent flowering and seed production. Three trials were established, firstly, to quantify the gains that have been made in the first generation of improvement in the breeding programme and, secondly, to establish whether a number of seed source and orchard variables influence the performance of the progeny. These variables were the amount of flowering trees in the seed orchard, year of seed collection, seed orchard origin and composition of seed orchard bulks. Diameter at breast height and tree heights were measured in the trials at between 87 and 97months after establishment, and timber volumes and survival were calculated. Improved seed orchard bulks performed significantly better (p < 0.01) than unimproved controls in the field trials. Genetic gains ranging from 23.2 to 164.8m3 ha−1 were observed over the unimproved commercial seed. There were significant differences (p < 0.01) in progeny growth between the levels of seed orchard flowering, with higher levels of flowering (≥40%) producing substantially greater progeny growth than lower flowering levels (≤20%). The seed orchard had no effect on progeny growth in this trial series. This suggests that seed collected from any of the four seed orchards tested will produce trees with significant improvement in growth. Springer-Verlag Berlin Heidelberg, 2013 E. nitens nationallicence Genetic gain nationallicence Tree improvement nationallicence Breeding nationallicence Flowering levels nationallicence Seed bulk composition nationallicence Swain Tammy-L Institute for Commercial Forestry Research, Scottsville, P.O. Box 100281, 3209, Pietermaritzburg, South Africa aut Verryn Steve Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Hatfield, Private Bag X20, 0028, Pretoria, South Africa aut Laing Mark School of Agricultural Earth and Environmental Sciences (SAEES), University of KwaZulu-Natal, P.O. Box 375, 3201, Pietermaritzburg, South Africa aut Tree Genetics & Genomes Springer-Verlag 9/3(2013-06-01), 767-778 1614-2942 9:3<767 2013 9 11295 https://doi.org/10.1007/s11295-013-0593-0 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11295-013-0593-0 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Swain Tammy-L Institute for Commercial Forestry Research, Scottsville, P.O. Box 100281, 3209, Pietermaritzburg, South Africa aut NATIONALLICENCE 700 1- Verryn Steve Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Hatfield, Private Bag X20, 0028, Pretoria, South Africa aut NATIONALLICENCE 700 1- Laing Mark School of Agricultural Earth and Environmental Sciences (SAEES), University of KwaZulu-Natal, P.O. Box 375, 3201, Pietermaritzburg, South Africa aut NATIONALLICENCE 773 0- Tree Genetics & Genomes Springer-Verlag 9/3(2013-06-01), 767-778 1614-2942 9:3<767 2013 9 11295 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer