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In 2004, abundant flowering of Norway spruce (Picea abies (L.) Karst.) was observed in two second- generation seed orchards: (1) ‘Outbreeding’, promoting crossing between clones of five geographically distant populations; and (2) ‘Kolonowskie’, restoring a population whose offspring exists only in an international experiment (IUFRO 1964/1968). In bothseed orchards, female strobili were produced by 91.3% and 91.7% of clones, represented by 64.1% and 55.5% of grafts, respectively, and statistically significant differences between clones were found in the number of mature cones. In the case of the seed orchard ‘Outbreeding’, the number of mature cones in individual clones was significantly correlated with latitude of the origin of maternal populations (r = 0.8826, p = 0.0470). The majority (95%) of cones in seed orchards ‘Outbreeding’ and ‘Kolonowskie’ were produced by only 28.2% and 38.5% of all clones, and 21.4% and 25.7% of all grafts, respectively. These data attest to a disparity between the level of genetic diversity in seed orchard progeny resulting from the observed numbers of cone-bearing clones and grafts and the genetic diversity expected from the actual participation of clones and grafts in seed orchard composition. The estimated seed production per 1 ha of seed orchard area in 2004 reached 21.05 kg for ‘Outbreeding’ and 21.72 kg for ‘Kolonowskie’.
Seed orchards are expected to produce geneticaly improved seeds while maintaining a sufficiently large genetic diversity. Field trials comparing open-pollinated Scots pine progeny from seed orchards and commercial seed stands were established at five climaticaly different sites in Poland. The paper presents first height measurements obtained on trees at age 4. Seedlots differed significantly, but there was no strong evidence of better performance of clonal seed orchards progeny over the progeny of production seed stands. There was no distinct geographical trend in the origin of the best growing seedlots, but populations from the northern part of country tend to perform better than south-eastern ones. Progeny of the local production seed stands at their native environment were not the best, except in one case. A strong site effect reflecting a fertility gradient of the planting sites was found.
The flowering and graft mortality of Norway spruce clones of Istebna origin was only slightly different from clones of other origin in the same seed orchard. The negative effect ofmoving Istebna clones from the south to the north of their origin was probably compensated by moving them from a higher altitude to lowland. There is a danger that the complete loss of several clones, observed in the seed orchard with time,may really decrease the expected level of genetic variation in the progeny. It is recommended that the mortality of grafts and the reduction in the number of clones in the seed orchard should be under permanent observation.
Field trials with open-pollinated progeny of Scots pine were established in 2004 at five climatically different sites of the Polish lowlands. This long-term experiment was aimed to compare the genetic variation and genetic value of the offspring of twenty two seedling seed orchards and two second-generation seed orchard with the offspring of the local so-called economic seed stands, which are the main source of seeds for artificial regeneration of Scots pine in Poland. The early evaluation of quantitative traits of cones, seeds and 1-year-old seedlings attests to remarkable variation between the studied populations. Significant linear correlatios were found between some of the studied traits.
The paper describes the measures adopted by the Czech State Forests for the conservation and reproduction of the Norway spruce gene pool in the Moravian-Silesian Beskid Mts. In addition to the assurance of natural regeneration in genetically valuable stands and the use of high-quality autochthonous stands as seed sources for artificial regeneration, the measures include selection of plus-trees, establishment of seed orchards, seed stands and clone archives, and identification of gene pools. Seeds of the most valuable regional populations are deposited in a seed bank.
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Picea abies in Northrhine-Westphalia

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The Sauerland region of southern Westphalia has the most economic stands of Norway spruce in the state of Northrhine-Westphalia (Germany). As shown by historical research and genetic analysis, the seeds for these stands were imported from Thuringia around the year 1880. Therefore, the two states are collaborating closely to secure the genetic variety of the spruce and develop new sources of seed supply. The survival of the Hochsauerland Norway spruce is now under threat: these stands have already been harvested or are due for harvesting shortly, in addition, many of the older stands were destroyed by the gale "Kyrill" in 2007, and only a few stands have remained. Since its foundation, the Forest Gene Bank of Northrhine-Westphalia has taken the following measures to preserve the gene pool of the Hochsauerland spruce and conserve it in the long term: storage of seed from 100 representative trees in all the most valuable stands of spruce (since 1985); establishment of seed orchards; and establishment of replacement stands. Thanks to those measures, the genetic information of the Norway spruce stands of Thuringian origin has been secured, and substantial stocks of seed are available for reforestation.
The abundant flowering, observed in 2004 in a model outbreeding seed orchard established in Kórnik, Poland, promoted crossing between clones of five geographically distant populations of Norway spruce. The clones were selected from a group of ca. 1100 provenances participating in the international IUFRO 1964/68 experiment and performing best in terms of growth traits and adaptability. In the seed orchard, 91.3% of clones and 64.1% of grafts produced female and/or male strobili. Statistically significant differences between the clones were only found in the number of mature cones produced. The mean number of mature cones in individual clones was also significantly correlated with the latitude of the place of origin of maternal populations (r = 0.88, p = 0.047). The nearly equal percentages of clones representing each of the five populations in the outbreeding seed orchard (from 23.2 to 17.5%) resulted finally in the highly unequal production of full seeds by each population (from 62.9 to 0.7%). These data provide evidence to suggest that the level of genetic diversity in the progeny, expected from the number of growing clones, diverges from the level resulting from the contribution of clones to the full seed production which is an effective measure of the genetic composition of progeny. To avoid this divergence, an outbreeding seed orchard could be established with unequal proportions of clones from different provenances, considering the knowledge of their flowering phenology, and individual variation in flowering and cone production.
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In the last decades, clone testing has become an important component of the long-term breeding and seed orchards for Norway spruce in Sweden. For more than three decades, considerable resources have been spent on testing clones intended for clonal forestry, but the Swedish forestry never saw it worth to pay the added cost involved in the added gain. The efforts, however, resulted in many clone trials and developments in the technique for clone production and propagation. Theoretically, clone testing is faster and cheaper than progeny testing and more reliable than selecting individuals forwards. Nowadays, the main line in long-term breeding is to make crosses between the best trees and test-cloned full-sibs as a recruitment population for long-term breeding and seed orchards. Since controlled crosses are a bottleneck for long-term breeding, a possibility is to rely on wind pollination (Breeding Without Breeding; BWB) in trials for testing clones. The seed parent is known, and that the pollen parent is a desirable genotype can be checked by molecular markers. BWB has the potential to eliminate the waiting time between selection and recombination, which is particularly important in a late and irregularly flowering species such as Norway spruce. Clone testing ensures that the breeding values are known from the same tests as those used for BWB. Another option for BWB is to place in seed orchards a few ramets of clones belonging to the breeding population, but normally not deserving such a use, with the hope that their presence will make it possible to rely on wind pollination to recombine the whole breeding population.
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