Phylogeny of Rubus (Rosaceae): Integrating molecular and morphological evidence into an infrageneric revision

Abstract

Rubus (Rosaceae), one of the most complicated angiosperm genera, contains about 863 species, and is notorious for its taxonomic difficulty. The most recent (1910–1914) global taxonomic treatment of the genus was conducted by Focke, who defined 12 subgenera. Phylogenetic results over the past 25 years suggest that Focke's subdivisions of Rubus are not monophyletic, and large‐scale taxonomic revisions are necessary. Our objective was to provide a comprehensive phylogenetic analysis of the genus based on an integrative evidence approach. Morphological characters, obtained from our own investigation of living plants and examination of herbarium specimens are combined with chloroplast genomic data. Our dataset comprised 196 accessions representing 145 Rubus species (including cultivars and hybrids) and all of Focke's subgenera, including 60 endemic Chinese species. Maximum likelihood analyses inferred phylogenetic relationships. Our analyses concur with previous molecular studies, but with modifications. Our data strongly support the reclassification of several subgenera within Rubus. Our molecular analyses agree with others that only R. subg. Anoplobatus forms a monophyletic group. Other subgenera are para‐ or polyphyletic. We suggest a revised subgeneric framework to accommodate monophyletic groups. Character evolution is reconstructed, and diagnostic morphological characters for different clades are identified and discussed. Based on morphological and molecular evidence, we propose a new classification system with 10 subgenera: R. subg. Anoplobatus, R. subg. Batothamnus, R. subg. Chamaerubus, R. subg. Cylactis, R. subg. Dalibarda, R. subg. Idaeobatus, R. subg. Lineati, R. subg. Malachobatus, R. subg. Melanobatus, and R. subg. Rubus. The revised infrageneric nomenclature inferred from our analyses is provided along with synonymy and type citations. Our new taxonomic backbone is the first systematic and complete global revision of Rubus since Focke's treatment. It offers new insights into deep phylogenetic relationships of Rubus and has important theoretical and practical significance for the development and utilization of these important agronomic crops.

Palynomorphological study of Azerbaijanian Rubus species in comparison with the morphology of pollen of the whole genus

“…Signi cant distinguishing features in our specimen R. saxatilis were not identi ed. This species was placed in subgenus Cylactis by Fokke (1910Fokke ( -1911Fokke ( , 1914), the last system (Huang et al 2023) dispose it in Melanobathus. Cyclatis is more diverse on the basis of exine sculpture (Xiong et al 2019), R. pungens is only one described pollen species, redisponed in Melanobathus, it has pollen and exine structure like R. saxatilis.…”

“…The genus Rubus belongs to the subfamily Rosoideae Fokke and consists of 10 to 16 subgenera (Fokke 1910(Fokke -1911(Fokke , 1914 Huang et al 2023). Two large subgenera of raspberries (Idaeobatus (Focke) Focke) and blackberries (Rubus) establish two evolutionary lines, where isolation is con rmed by molecular genetic studies, as well as morphological features, the most important of which is the fruit structure (Alice et al 1999;Krasovskaya 2001;Kalkman 2004;Potter et al 2007; Kamnev et al 2020;Dunaeva et al 2022).…”

Rediscovery of Rubus pendulus Rusby (Rosaceae) and a new record for the flora of Ecuador and Peru

“… Rubus L. presents ca 836 species classified in 10 subgenera; thus, being one of the most diverse genera of the Rosaceae family ( Huang et al 2023 ). Despite the cosmopolitan distribution of the genus, it is more abundant in Asia, where at least 208 species (139 endemic) were reported in China alone ( Lingdi and Boufford 2003 ).…”

Rubus dhauladharensis (Rosaceae), a New Species from Himachal Pradesh, India

“…According to Huang et al . (2023), there are 863 species, but POWO (https://powo.science.kew.org/results?f=species_f%2Caccepted_names&q=rubus) lists over 1500 accepted species mostly distributed in temperate regions as well as on subtropical and tropical mountains. The species were previously classified into 12–15 subgenera (Focke 1910–1911, 1914, Jennings 1988, Daubeny 1996), but only ten monophyletic clades were established in the phylogenetic analyses of Rubus by Huang et al .…”

“…The species were previously classified into 12–15 subgenera (Focke 1910–1911, 1914, Jennings 1988, Daubeny 1996), but only ten monophyletic clades were established in the phylogenetic analyses of Rubus by Huang et al . (2023).…”