Systematics and Genetics: Medicinal effects of rosehips are attributed mainly to dogroses, i.e. species in Rosa sect. Caninae. These are mostly pentaploid and have a unique meiosis with asymmetrical chromosome distribution. Offspring in reciprocal crosses differ widely since seedlings resemble the seed parent more than the pollen parent. Keywords: Antioxidant, functional food, medicinal plant, phytotherapy, plant breeding, plant taxonomy.

The genus Harpagophytum has two species: H. procumbens which is an important medicinal plant in southern Africa, and H. zeyheri. Genetic diversity in 96 samples, obtained by germinating seeds collected from Botswana, was assessed using six inter-simple sequence repeat (ISSR) and 10 random amplified polymorphic DNA (RAPD) primers. These DNA markers yielded a total of 138 polymorphic bands. Polymorphism information content (PIC) ranged from 0.06 to 0.39 for ISSR primers, and from 0.09 to 0.43 for RAPD primers. Jaccard's similarity coefficients were highest when seedlings derived from the same fruit capsule were compared, while seedlings from different fruits on the same plant had intermediate values. The lowest values were recorded among seedlings from different plants. These results were consistent with an outcrossing breeding system in Harpagophytum. Analysis of molecular variance revealed significant differentiation (P<0.01) between taxonomic units within Harpagophytum. About 39% of the variability occurred between the two species, H. procumbens and H. zeyheri. Plants with an intermediate morphology, i.e. putative hybrids (PH), showed 21% differentiation when compared with H. procumbens ssp. procumbens (PP), and 19% when compared with H. procumbens ssp. transvaalense (PT) or with H. zeyheri (ZZ). In addition, a deviating variant of PT was identified, here termed 'procumbens new variety' (PN). PN showed only 9% differentiation when compared with PT, 22% when compared with PP or with PH, and 41% when compared with ZZ. Considerable differentiation between the two Harpagophytum species was revealed also by a cluster analysis. Introgression was, however, suggested by the intermediate position of the putative hybrid plants in a principal component analysis while inter-specific gene flow was shown by a Bayesian genetic structure analysis.

All dogroses (Rosa sect. Caninae) are characterized by the peculiar canina meiosis in which genetic material is unevenly distributed between female and male gametes. The pan-canina rDNA family (termed beta) appears to be conserved in all dogroses analyzed so far. Here, we have studied rDNAs in experimental hybrids obtained from open pollination of F1 plants derived from 2 independent intersectional crosses between the pentaploid dogrose species (2n = 5x = 35) Rosa rubiginosa as female parent (producing 4x egg cells due to the unique asymmetrical canina meiosis) and the tetraploid (2n = 4x = 28) garden rose R. hybrida ‘André Brichet' as male parent (producing 2x pollen after normal meiosis). We analyzed the structure of rDNA units by molecular methods [CAPS and extensive sequencing of internal transcribed spacers (ITS)] and determined the number of loci on chromosomes by FISH. FISH showed that R. rubiginosa and ‘André Brichet' harbored 5 and 4 highly heteromorphic rDNA loci, respectively. In the second generation of hybrid lines, we observed a reduced number of loci (4 and 5 instead of the expected 6). In R. rubiginosa and ‘André Brichet', 2-3 major ITS types were found which is consistent with a weak homogenization pressure maintaining high diversity of ITS types in this genus. In contrast to expectation (the null hypothesis of Mendelian inheritance of ITS families), we observed reduced ITS diversity in some individuals of the second generation which might derive from self-fertilization or from a backcross to R. rubiginosa. In these individuals, the pan-canina beta family appeared to be markedly enriched, while the paternal families were lost or diminished in copies. Although the mechanism of biased meiotic transmission of certain rDNA types is currently unknown, we speculate that the bivalent-forming chromosomes carrying the beta rDNA family exhibit extraordinary pairing efficiency and/or are subjected to strong selection in Caninae polyploids.

The purpose of the study was to support the selection process of the most valuable currant and gooseberry accessions cultivated in Northern Europe, in order to establish a decentralized core collection and, following the selection, to ensure sufficient genetic diversity in the selected collection. Molecular analyses of the material from nine project partners were run at seven different laboratories. The results were first analysed for each partner separately, and then combined to ensure sufficient genetic diversity in the core collection.

in Undetermined Rubus sordirosanthus (sect. Corylifolii Lindl.) was published, although invalidly, by Hylander 1958 from the province of Halland, south-western Sweden. A holotype is here provided to make the name validly published. Recent field studies have shown that it occurs at almost 100 localities in a restricted area of c. 6 km around Steninge in central Halland. In addition, it is found on a former refuse tip in the city of Halmstad, 23 km to the south. A morpho- logically similar form has been found in three places at roadsides around the city of Varberg, 33 km to the north. We have used genetic methods to investigate the relation between these forms and the related species R. wahlbergii Arrh. The chromosome num- ber of R. sordirosanthus from Steninge and Halmstad, as well as the Varberg form is 2n=28, in contrast to 2n=35 for R. wahlbergii. Moreover, RAPD DNA analysis shows that the two species are genetically separated. Rubus sordirosanthus from Steninge and Halmstad is homogeneous, whereas the Varberg form differs, although not in the direction towards R. wahlbergii. The latter species is genetically quite diverse. Thus, R. sordirosanthus is a well-defined and locally abundant species in Halland. On the other hand, the Varberg form gives the impression of being introduced in Varberg and therefore probably occurs also in other areas. Typification: Rubus sordirosanthus H. Hyl. ex Ryde nov. spec. Descr. orig.: H. Hylander, Botaniska Notiser 111, p. 521 (1958). Icon. (holotypus): Ibid. p. 522, fig. 3. Holotypus: Halland, Steninge bruk, O om Bracketorp, ”angen”, 13/7 1951. leg. H. Hylander (LD). (Less)

Intersectional crosses were performed between pentaploid dogrose species (Rosa sect. Caninae) as seed parents and different tetraploid garden roses as pollen parents. From 2810 crossings and with approximately 10% germination, 298 seedlings were obtained. Of these, more than 75% came from crosses with 10 different plants of R. rubiginosa as seed parents and either double flowering Rosa hybrida ‘André Brichet’ (cross 1) or the single flowering Canadian germplasm L83 (cross 2) as pollen parents. Selected seedlings from these two cross combinations together with their parents were used for a study with microsatellite markers. All studied seedlings obtained all alleles from their seed parents with two minor exceptions. In cross 1, 49% of the seedlings were hexaploid, and 51% were pentaploid, whereas in cross 2, 92% were hexaploid and only 8% were pentaploid. The pentaploid seedlings had not received any alleles from the pollen donor and were regarded as being of apomictic origin. The hexaploid seedlings had received two alleles from their pollen donor and were regarded as true hybrids. The alleles of the pollen donors appeared to segregate randomly to the seedlings, both the specific and the ones in common with the seed parents. As the 10 R. rubiginosa plants used as seed parents were extremely homogenous, the differences in rate of true, hexaploid hybrids versus pentaploid apomicts appears to be governed mainly by the pollen donor. Approximately half of the cross 1 hybrid seedlings had flowers with more than 5 petals, consistent with ‘André Brichet’ being simplex for the gene governing double flowers, but none of the plants from any cross combination showed recurrent flowering. All seedlings were more susceptible to leafspot caused by the fungi Sphaceloma rosarum and/or Septoria rosae compared to their seed parents, but there was no increase in infection of blackspot caused by Diplocarpon rosae and even a slight decrease in powdery mildew in cross 1. There were three times more rosehip fly larvae in rosehips from cross 2 vs. cross 1, probably due to differences in chemical composition of hips. _____________________________________________________________________________________________________________

Sesame (Sesamum indicum L.) is a traditional oil crop cultivated throughout South East Asia. To estimate the genetic diversity of this crop in parts at the region, 22 sesame accessions collected in Vietnam and Cambodia were analyzed using 10 RAPD markers. The 10 primers generated 107 amplification products of which 88 were polymorphic fragments (83%). Genetic diversity of all populations was Ht = 0.34 when estimated by Nei’s genetic diversity and species diversity was H′sp = 0.513 when estimated by Shannon diversity index. Genetic distance ranged from 0.03 to 0.43, with a mean genetic distance of 0.23. The unweighted pair group method with arithmetic averages (UPGMA) cluster analysis for the 22 accessions divided the material in four groups. The dendrogram revealed a clear division among the sesame accessions based on their geographical region. Interestingly, some geographically distant accessions clustered in the same group, which might indicate the human factor involved in the spreading of sesame varieties. The high level of polymorphism shown suggests that RAPD techniques can also be useful for the selection of parents in sesame (Sesamum indicum L.) breeding program and for cultivar differentiation.

This chapter contains sections titled: Introduction Taxonomy Utilization Production Genetics and Breeding Summary Literature Cited

The genus Rosa has a complex evolutionary history caused by several factors, often in conjunction: extensive hybridization, recent radiation, incomplete lineage sorting, and multiple events of polyploidy. We examined the applicability of AFLP markers for reconstructing (species) relationships in Rosa, using UPGMA clustering, Wagner parsimony, and Bayesian inference. All trees were well resolved, but many of the deeper branches were weakly supported. The cluster analysis showed that the rose cultivars can be separated into a European and an Oriental cluster, each being related to different wild species. The phylogenetic analyses showed that (1) two of the four subgenera (Hulthemia and Platyrhodon) do not deserve subgeneric status; (2) section Carolinae should be merged with sect. Cinnamomeae; (3) subsection Rubigineae is a monophyletic group within sect. Caninae, making sect. Caninae paraphyletic; and (4) there is little support for the distinction of the five other subsections within sect. Caninae. Comparison of the trees with morphological classifications and with previous molecular studies showed that all methods yielded reliable trees. Bayesian inference proved to be a useful alternative to parsimony analysis of AFLP data. Because of their genome-wide sampling, AFLPs are the markers of choice to reconstruct (species) relationships in evolutionary complex groups.

Introduction of germplasm from wild species is a prerequisite for the enlargement of the relatively small gene pool in roses. In the present study testcrosses between different European wild species and selected tetraploid cultivated roses were made to evaluate crossing efficiencies. Significant differences were observed among the tested combinations. Interspecific crosses frequently generate F1 plants with odd chromosome numbers (mostly triploids). These triploids produce both monoploid and diploid pollen fractions. Pollen sorting could increase the percentage of diploid pollen before it is used for pollination. To evaluate the genetic transfer between wild and cultivated roses a protocol for making DNA microsatellites profiles of a single pollen was developed.

Blackberries growing in forests regenerate mainly in a vegetative way; however, detailed studies have shown substantial variability in performance of Rubus individuals. The main problem is if the differences among plants are genetically based, or are due to site heterogeneity? This study was aimed at determining 1) how large are the differences in performance of individual plants and how persistent they are during consecutive years, 2) how much of that variability can be explained by the local environmental conditions, especially the intensity of competition among plants, and whether the performance of individual plants is related to their genetic characteristics. In a partially cut mature beech forest in Western Carpathians 35 randomly chosen individuals of Rubus hirtus (Waldst. & Kitt) were tagged and measured each year for 9 years. Ten largest and ten smallest individuals were selected for genetic analysis. Mean size of individual plants differed between consecutive growing seasons, but the overall size ranking was quite consistent throughout the entire period of study. Analysis of environmental variables: relative light intensity and local abundance of potential competitors explained about 24% of the differences in individual plant performance. In the genetic analysis the five primers were applied to analyse all 20 samples. The five primers produced 10 polymorphic bands, showing a high variability. Only a few samples displayed identical band patterns, indicating either vegetative propagation or apomictic origin. Distribution of the results of Spearman's rank correlation of plant size among genetically related individuals did not differ significantly from the distribution of rank correlation coefficients in the entire sample. In the analysed population genetical affinity did not seem to correlate with the performance of Rubus hirtus.

A series of intra- and interspecific crosses in Rubus was evaluated with DNA markers to assess the proportion of apomictically vs. sexually derived progeny plants. The species were well separated from each other with these markers and the interspecific hybrids were easy to ascertain. Ten plants each were derived by selfing of R. hartmanni, R. polyanthemus and R. vestitus, and evaluated with RFLP. Of these plants, only one R. hartmanni plant appeared to be sexually derived, whereas the remainder appeared to have arisen by apomixis. Between 10 and 19 progeny plants, derived by open pollination of R. Hartmanni, R. infestus, R. laciniatus and R. vestitus, respectively (total of 63plants), were evaluated with RFLP. Of these, 6 plants (approx. 10%) showed as lightly deviating band pattern, which may indicate sexual seed set but could also result from experimental artefacts. The three species combinations 1) R. hartmanni and R. sprengelii, 2) R. infestus and R. vestitus, and 3)R. laciniatus and R. polyanthemus were cross-pollinated reciprocally and the resulting progenies evaluated with RAPD (combinations 1 and 2)and leaf shape (combination 3). Combination1 produced 20% (3 out of 15 progenies)sexually derived progenies, combination 2produced 100% (26 progenies) and combination 3 produced 64% (16 out of 26progenies), respectively. The hybrid progenies appeared to have been derived through pollination of unreduced as well as reduced egg cells. The ability to produce interspecific hybrid progenies is most probably dependent upon the species combination.

Werlemark, G. 2000. Genetic variability and reproductive strategies in Nordic dogroses, Rosa section Caninae. ISSN 1401-6249, ISBN 91-576-5775-0 In the present thesis, I investigate the morphological variation among and within Nordic dogrose species (Rosa section Carzirzae), and the transmittal of morphological characters and molecular markers to interspecific progeny plants. The occurrence of apomixis within the section is also investigated. All species within section Caninae are polyploid and characterised by their unique meiosis with unequal distribution of maternal and paternal chromosomes to their progeny. The pollen parent contributes only seven chromosomes, whereas the seed parent contributes 21, 28 or 35 chromosomes depending on ploidy level. The dogrose species are morphologically rather distinct. Both reproductive and vegetative morphological characters could differentiate among the investigated taxa, with the exception of the two subspecies of R. dumalis, subsp. corifoliia and subsp. dumalis. Rosa rubiginosa appeared to be the most homogeneous of the species, both within and among populations, and R. dumalis the most heterogeneous, both within and among populations. Rosa villosa was heterogeneous among populations but showed high within-population homogeneity. Morphological characters could also separate interspecific hybrids from progeny groups representing the parental species and the influence from the seed parent was apparent as expected from the skewed distribution of chromosomes. The matroclinal inheritance of molecular markers is also very pronounced, since all but two maternal markers were transmitted to all the interspecific progeny plants. In contrast, only approximately half of the paternal markers were transmitted to the progenies. The degree of homology between the constituent genomes in the parents decide to what extent the genetic contribution of the pollen parent will be recognizable in the progeny plant, both in morphological characters and in molecular markers. The genomes could be separated by size polymorphism in their respective NOR sites. Apparently two of the five consituent genomes in one pentaploid plant were never involved in the bivalent formation. Apomixis appears to occur to a limited extent within the dogroses, indicated by elevated pollen viability compared to the experimentally derived hybrid plants, and a complete lack of paternal parent-specific molecular markers.

Difficulties in delimiting well-defined entities in the dogroses (Rosa sect.Caninae) has resulted in very variable taxonomic treatments. The present study was undertaken to provide a background for taxonomy as well as plant breeding. Morphometric diversity was analysed on seedlings obtained from field collections in South Sweden of three species,Rosa dumalis, R. rubiginosa andR. villosa. A canonical variates analysis showed that the three species are relatively distinct whereas two subspecies ofR. dumalis were less well discriminated. Analyses of variance demonstrated that intraspecific variation is pronounced inR. dumalis and, to a lesser extent, inR. villosa.

We have analysed samples from Sweden, Denmark, and Germany of six facultatively apomictic blackberry species to investigate the accordance between a taxonomy based on morphological characters on the one hand, and distribution of genetic variation estimated by DNA fingerprinting on the other hand. DNA fingerprint variation was found to be quite restricted in all species investigated. The first taxonomic group included three species related toRubus nessensis, two being characterized by one very widespread DNA fingerprint in all three countries and a few rare ones, whereas the third species differed between Sweden and Germany. The second taxonomic group included species related toR. gracilis. Two of these species exhibited very similar DNA fingerprints, whereas the third species deviated clearly. The utilization of DNA fingerprinting as a tool in taxonomy is discussed; most likely this method could become a useful complement to morphology, especially in plant groups with reduced levels of genetic recombination.