Martin Rogge’s research while affiliated with Landesbetrieb Wald und Holz NRW and other places

Nach der Novelle des Bundesnaturschutzgesetzes dürfen bei Pflanzungen in der freien Natur nur noch gebietseigene Gehölze verwendet werden. Die Übergangsregelung endete im März 2020 und Experten sehen große Lücken bei der Versorgung mit gesetzeskonformen Gehölzen.

Die aktuellen Kalamitäten stellen Forstbetriebe vor große Herausforderungen. Zurzeit überbieten sich die Akteure aus den verschiedenen Bereichen der Forstwirtschaft mit Vorschlägen und Ideen zur Bewältigung dieser Krise – mal mehr, mal weniger sachlich fundiert. Im vorliegenden Artikel soll deshalb aufgezeigt werden, wie die Probleme insbesondere der Verjüngung und Wiederaufforstung von Schadflächen fachkundig analysiert und zukünftige Entscheidungen auf forstwissenschaftlich fundierter Grundlage gefällt werden können. Darüber hinaus soll der Beitrag Hilfestellungen geben, um die Situation für Forstbetriebe zu entschärfen und das Miteinander von Waldbesitz und Forstbaumschulen zu verbessern.

Der Artikel schildert die Situation am Markt für gebietseigene Gehölze im Jahr 2019 und setzt sich kritisch mit dem Maßnahmen des BMU und der Naturschutzbehörden der Länder auseinander. Deutsche Baumschule 06/2019

With the end of the transition period formulated in Article 40 (4) of Germany's Federal Nature Conservation Act, producers of propagation material of indigenous woody species are challenged to identify suitable seed sources. Production of seed in orchards presents an important alternative to natural seed sources. Neither the Act nor the 'Guidelines for deployment of indigenous woody species' stipulate explicit standards for seed orchards. Thus the Federal/Länder Working Group 'Forest Genetic Resources and Legislation on Forest Reproductive Material' elaborated standards based on population genetic considerations and on regulations already existing in some Länder and neighbouring countries. Recommendations on the composition and location of seed orchards, including isolation from conspecific sources, and harvesting operations are presented.

Crataegus laevigata und Crataegus monogyna eindeutig zu unterscheiden, ist für den Handel mit Saat- und Pflanzgut unbedingt notwendig, denn der Kunde, der später Pflanzen bestellt, erwartet artreine Ware. In der Praxis ist eine Unterscheidung aber oft schwierig. Bereits beim Beernten sollten hier Fehler vermieden werden.

Sloe (Prunus spinosa L.) is a shrub native to Europe. In Germany, 50–80 % of all planted sloe is imported. Little is known about the genetic diversity patterns within and between German sloe populations. Thus, a debate arose how to avoid risks for nature and landscape by planting potentially maladapted material. The main objectives of our study are to analyse the genetic differentiation pattern of sloe populations in Germany, to identify geographic/genetic structures and to evaluate their potential for tracing reproductive material. 17 natural populations from Germany and 1 from Italy and Hungary were investigated by Amplified Fragment Length Polymorphisms (AFLP) and PCR–RFLP techniques. The AMOVA analyses based on AFLPs for all populations and for the German populations only result in equally high differentiation values of ΦPT = 15 % of molecular variance between populations. The analysis of cpDNA PCR–RFLPs resulted in 24 haplotypes with 30 % showing genetic variation between populations. Overall values of genetic variability over all loci and populations are: Na = 0.832, Ne = 1.114 and He = 0.072. Mantel tests for AFLPs and cpDNA haplotypes reveal no association between geographic and genetic distances between populations as a result of a lack of differentiation between German populations and those from southern and southeastern Europe. Weak geographic/genetic patterns were observed on a large scale. However, these concern the German populations only. Our results indicate that vegetative regeneration in combination with founder effects may influence the level of differentiation between populations. Populations with a large amount of vegetative propagation are more differentiated from other populations than those populations which exhibit less vegetative regeneration. The assignment of reproductive material (i.e. plant material) to potential source populations resulted in high values of correct allocations. Hence, such methods can be applied to trace reproductive material of unknown origin.

New regulations in landscaping using trees and shrubs of regional origin (§ 40 BNatSchG) require me thods for the identification of the geographical origin of its reproductive material. In this case study on pedunculate oak (Quercus robur L.) we present a DNA based procedure that enables the assign ment of seeds and young plant material to its origin stands of harvest. However, this method is not based on logistically complex and expensive systems of retaining samples that have to be taken and stored at each step of the chain-of-custody. For checking the origin of tree and shrub reproductive material, one inventory of the genetic structure of a seed production stand should be representative over a longer period of time as long as no distinct changes have been carried out in the structure of the populations.

Genetic diversity strongly influences populations' adaptability to changing environments and therefore survival. Sustainable forest management practices have multiple roles including conservation of genetic resources and timber production. In this study, we aimed at better understanding the variation in genetic diversity among adult and offspring individuals, and the effects of mating system on offspring survival and growth in wild cherry, Prunus avium. We analysed adult trees and open pollinated seed-families from three stands in Germany at eight microsatellite loci and one incompatibility system locus and conducted paternity analyses. Seed viability testing and seed sowing in a nursery allowed further testing for the effects of pollen donor diversity and genetic similarity between mates on the offspring performance at the seed and seedling stages. Our results were contrasting across stands. Loss of genetic diversity from adult to seedling stages and positive effect of mate diversity on offspring performance occurred in one stand only, whereas biparental inbreeding depression and significant decrease in fixation index from adults to seedlings was detected in two stands. We discussed the effects of stand genetic diversity on the magnitude of biparental inbreeding depression at several life-stages and its consequences on the management of genetic resources in P. avium.Heredity advance online publication, 5 December 2012; doi:10.1038/hdy.2012.103.

Well-adapted, high quality reproductive material is key to the success of forest plantations. Consequently in many countries the collection and trade of forest reproductive material is regulated. Paper documents are usu-ally the only evidence for the origin of forest reproductive material. Certification schemes already established in Germany use genetic inventories to compare reference samples collected at different steps of the chain-ofcustody. A new approach using DNA-fingerprints efficiently controls the origin of seed sources without these multiple reference samples. Only a sample of adult trees within the seed stands is needed. The control is directly made for each suspicious plant or a group of suspicious plants by use of multilocus genotype assignment. We made a field test with samples of adults and seedling from 5 registered seed stands of Quercus robur in Western Germany. Eight highly variable nuclear microsatellites were used to genotype each individual. We found in total 255 different alleles at all loci in the adult populations. The observed levels of genetic variation (A e= 9.18), genetic differentiation (delta = 0.187) and population fixation (F ST = 0.01) were slightly higher than results of similar studies. Individual and group assignment tests were performed with the Bayesian multi-locus approach. The proportion of correctly assigned seedlings was 65% for individuals with completely scored genotypes. In all 5 cases the groups of seedlings were assigned to the correct seed stand and an additional sample of seedlings from another stand could be successfully excluded with a probability test. The conclusion of the field study is that a large scale application of this new approach to control of the origin of forest reproductive material is feasible.

Chloroplast DNA markers give valuable information about the geographic origin of oaks and other angiosperms due to their maternal inheritance and the absence of recombination, thus reflecting patterns of seed dispersal. Since the dispersal by seeds is restricted as compared to pollen dispersal, cpDNA markers show low variation within populations but strong differentiation among populations. Because differentiation patterns are strongly associated with the postglacial recolonization history of oaks, the identification of the chloroplast variants (haplotypes) gives valuable information about the geographic origin of populations. We identified chloroplast haplotypes in a total of 24 Quercus robur populations from four regions in North Rhine-Westphalia established between the early 18 th to the middle of the 19 th century before extensive seed trade with the expansion of railway connections started. Additionally, 63 very old trees (between 250 and 700 year old) from one region were analysed at the same cpDNA markers. A similar haplotype composition was found in the old solitary trees and in the old oak stands from the same region. H1 as the most frequent variant in western Germany is also the most frequent type in the present study (71.5%) followed by H12 (21.5%), H10 (4.9%), H11 (about 1%) with a centre of distribution in South Western and Western Europe (Petit et al., 2002b), and H7-26 (about 1 %) as the most frequent type in South Eastern Germany. There was considerable genetic variation among populations (58.9%) and geographic regions generally allowing for the identification of stands that had been established with introduced nonindigenous plant material. By analysing very old oak stands that had been established before extensive human seed transfer began, we can gain insights in the cpDNA haplotype composition in the past of that region. In combination with the knowledge on the haplotype distribution in more than 2600 populations in Europe we have very good reference data to distinguish between natural patterns of postglacial recolonization of the species and human interference due to long distance seed transfer.