Systematics of the Rubus fruticosus aggregate (Rosaceae) and other exotic Rubus taxa in Australia

Abstract

Exotic Rubus taxa in Australia have been revised following consultation with European and North American experts in Rubus, allied with studies of variation in patterns of DNA restriction fragments and morphology. Many of these taxa have names that are applied for the first time in Australia (prefaced with a †). The major focus of the work was the Rubus fruticosus L. aggregate and taxa of this aggregate covered here are R. anglocandicans A. Newton, R. cissburiensis W.C. Barton & Ridd., †R. echinatus Lindl., †R. erythrops Edees & A. Newton, R. laciniatus Willd., R. leightonii Lees ex Leight. †R. leucostachys Schleich. ex Sm., †R. phaeocarpus W.C.R. Watson, R. polyanthemus Lindeb., †R. riddelsdellii Rilstone, †R. rubritinctus W.C.R. Watson, R. ulmifolius Schott (including R. ulmifolius var. ulmifolius and †R. ulmifolius var. anoplothyrsus Sudre), and R. vestitus Weihe, along with two undescribed taxa, Rubus sp. Scott Creek (D.E. Symon 16504) and Rubus sp. Tasmania (J.R. Hosking 1551). Other naturalised taxa are R. alceifolius Poir., R. ellipticus Sm., R. idaeus L., †R. laudatus A. Berger, †R. loganobaccus L.H. Bailey, †R. philadelphicus Blanch., R. roribaccus (L.H. Bailey) Rydb. and R. rugosus Sm. Patterns of morphological and molecular variation among individuals of the R. fruticosus agg. in Australia were examined. In phenetic analyses based on examination of 137 herbarium specimens and 27 morphological characters, taxa showed varying degrees of separation. Some taxa, for example R. anglocandicans and the two varieties of R. ulmifolius, formed distinct groups in these analyses whereas there was considerable overlap among individuals of other species. Fifty M13/HaeIII DNA-banding patterns (phenotypes) were identified among 198 collections from the R. fruticosus agg. across Australia. Thirty-five DNA phenotypes were correlated with 15 taxa of the R. fruticosus agg.; the remaining 15 DNA types correlated poorly or were determined with only a moderate level of confidence. R. anglocandicans, R. echinatus, R. leightonii, R. leucostachys, R. sp. Tasmania, R. ulmifolius and R. vestitus had two or more DNA phenotypes whereas only one DNA phenotype was observed for the remaining eight taxa. Taxa that were more distinct with respect to their DNA phenotypes also tended to be more distinct with respect to morphology based on a Mantel matrix correlation test. Within taxa that were difficult to tell apart morphologically, those sharing the same DNA phenotype were considered members of the same Rubus taxon. These results are discussed in the context of the evolution and ecology of the R. fruticosus agg. in Australia and in relation to the incomplete taxonomy of Rubus in Europe and North America.

The Biology of Canadian Weeds. 154. Himalayan blackberry

“…The introduction of Himalayan blackberry to North America was part of a larger initiative in the 19th century to intentionally introduce clones of the R. fruticosus aggregate outside of their native range for fruit production (Hall 1990). Areas of introduction included North and South America, Australia, New Zealand, and South Africa (Evans et al 2007; USDA-ARS National Genetic Resources Program 2011). It was introduced to the Pacific Northwest region for cultivation in 1885 (Jennings 1988;Soll 2001;Murphy 2006) by Luther Burbank (Ceska 1999;Murphy 2006), a botanist, as Himalayan Giant (Hummer 1996).…”

Use of a trap garden to find additional genetically distinct isolates of the rust fungus Phragmidium violaceum to enhance biological control of European blackberry in Australia

“…Pathogenicity of isolates from the trap garden in France was classified as high (H) when>60% of inoculated (detached) leaflets or at least one of the inoculated leaves on whole shoots in each of the replicates were given a disease score of 3 or 4 (Table 4). Pathogenicity was classified as low (L) for all other isolateclone combinations, or non-pathogenic (N) if no uredinia whatsoever were produced on any of the leaflets inoculated in either bioassays (disease score of 0 or 1; Evans et al (2005) c Based on DNA phenotypes published in Evans et al (2007) d Detached-leaflet bioassays were performed in Montpellier (for isolates 6-4, 21-1, 28-2 and 32-2) or Canberra (for remaining isolates), while all whole-shoot bioassays were performed in Canberra only. Bold letters correspond to final ratings obtained in whole-shoot bioassays, except those for isolates on clones KE1 and EB22, which are based on results from both the detached-leaflet and whole-shoot bioassays unless indicated otherwise.…”

“…We now know that blackberry in Australia comprises at least 15 polyploid agamospecies, each with one or more genotypes, and one diploid, sexual species (Evans et al 1998(Evans et al , 2007, with Rubus anglocandicans the most widespread of these agamospecies (Evans and Weber 2003). Evans et al (2011) identified at least one Australian isolate capable of infecting the range of blackberry genotypes that have been characterised so far.…”

Dynamics of Introduced Populations of Phragmidium violaceum and Implications for Biological Control of European Blackberry in Australia

“…The distributions of various taxa of the R. fruticosus agg. can be found in a recent taxonomic update on exotic Rubus in Australia (17). Blackberry infestations in Australia may be discontinuous or continuous and of various sizes and shapes.…”

“…There are at least 15 taxa of European blackberry (Rubus fruticosus L. aggregate) in Australia, where this plant is regarded as an invasive species, infesting nearly 9 million hectares of land (17,41). Taxa of the R. fruticosus agg.…”