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Pedicularis

Pedicularis

Pedicularis

Pedicularis is a genus of perennial green root parasite plants currently placed in the family Orobanchaceae (the genus previously having been placed in Scrophulariaceae sensu latoFrom the limited available data,the species of Pedicularis in China are pollinated by bumblebees gathering nectar and/or pollen on nectariferous non-beaked species, and pollen only,by scraping or vibrating,on beaked species including those with long corolla tubes (Macior, L. W. 1988. Plant Species Biol. 3: 61--66.; Macior, L. W. & S. K. Sood. 1991. Plant Species Biol. 6: 75--81.; Macior, L. W., pers. comm.).The rank of series has been traditionally used in Pedicularis since the time of Prain's work (Ann. Bot. Gard. (Calcutta) 3: 1--196. 1890). Sections (and subgenera) have also been used (e.g., by Bunge in Walpers, Repert. Bot. Syst. 3: 409--433. 1844; Li, H. L. Proc. Acad. Nat. Sci. Philadelphia 101: 1--214. 1949; Yamazaki, T. 1988. A revision of the genus Pedicularis in Nepal. in: Ohba, H. & Malla, S.B. (eds.), The Himalayan Plants 1: 91--161, and others). Because series names have been used widely (e.g., Tsoong, P. C., 1955, Acta Phytotax. Sin. 4: 103--147; Tsoong, P.C., 1963, Fl. Reipubl. Popularis Sin. 68) but sectional names only in revisions covering limited areas (e.g., Yamazaki, T. 1988) and since not all species have been assigned to sections yet, the rank of series is used here.In medieval times, many plants were given names based on their uses or properties, both real and imagined. Lousewort (Pedicularis) got its name because of the belief that livestock grazing on the plant would get lice (and possibly transmit them to humans). There seems to be little evidence to support this claim, but it did not prevent Linnaeus from using the Latin word Pediculus (louse) for the plant’s genus name. Traditionally, Pedicularis has been included in the figwort family (Scrophulariaceae). Louseworts have green leaves and produce their own food through normal photosynthesis but also have roots capable of capturing nutrients and water from adjacent plants making them partially parasitic (or hemiparasites). Recent genetic studies have shown that Pedicularis and other hemiparasitic genera in the Scrophulariaceae (including the Indian paintbrushes, Castilleja) are better placed in the broomrape family (Orobanchaceae) with species that are true parasites that lack green chlorophyllFIGURE 1. Plant abundance (A), canopy cover (B) and above-ground biomass (AGB; C) of Pedicularis kansuensis under various fertilization regimes before (2013) and after (2014 and 2015) fertilization. Different letters indicate significant differences between treatments within the same year at P < 0.05, n = 4. Values are presented as means ± SE. Fertilization regimes: CK, unfertilized control; LN, fertilized with lower nitrogen level; HN, fertilized with higher nitrogen level; P, fertilized with phosphorus.Mardoian, B. C., and Borowicz, V. A. (2016). Impact of light limitation on mortality and early growth of the root hemiparasite Pedicularis canadensis L. J. Torrey Bot. Soc. 143, 1–7. doi: 10.3159/TORREY-D-15-00012.1Thirteen major clades are resolved with strong support, although the backbone of the tree is poorly resolved. There is little consensus between the phylogenetic tree and Tsoong’s classification of Pedicularis. Only two of the 13 groups (15.4 %), and 19 of the 56 series (33.9 %) with more than one sampled species were found to be strictly monophyletic. Most opposite-/whorled-leaved species fall into a single clade, i.e. clade 1, while alternate leaves species occur in the remaining 12 clades. Excluding the widespread P. verticillata in clade 1, species from Europe and North America fall into clades 6–8Our results suggest that combinations of morphological and geographic characters associated with strongly supported clades are needed to elucidate a comprehensive global phylogeny of Pedicularis. Alternate leaves are inferred to be plesiomorphic in Pedicularis, with multiple transitions to opposite/whorled phyllotaxy. Alternate-leaved species show high diversity in plant habit and floral forms. In the Himalaya-Hengduan Mountains, geographical barriers may have facilitated diversification of species with long corolla tubes, and the reproductive advantages of beakless galeas in opposite-/whorled-leaved species may boost speciation at high altitude.

Thirteen major clades, labeled 1–13, are addressed below in ascending order as they appear in the tree (Fig. 1). Support values are specified in the following text as BI PP/ML BS, e.g. 1.00/92 (PP/BS value). Phylogenies of the plastid (1.00/92) and total datasets (1.00/100) strongly supported clade 6 as the sister clade to the rest of Pedicularis (1.00/99). However, clade 6 was resolved as paraphyletic in the nrITS tree (Additional file 2). Within clade 6, 14 alternate-leaved species were from the informal groups Sceptrum (1) and Neosceptrum (2) in Tsoong’s system, with only three species of series Aloenses from the informal group Cyclocladus (3) with opposite leaves. Series Aloenses (excluding P. petelotii, 1.00/100), Recurvae (1.00/100), and Sceptra (0.68/51) in clade 6 were more or less supported as monophyleticSubclade 1C (1.00/62) included 50 species (65 samples), with two long-tubed species, i.e. P. urceolata (series Urceolatae) and P. oxyrhyncha (series Flexuosae). The monophyletic series Rigidae and Tatsienenses, and paraphyletic series Lyratae were included in this subclade. It is noteworthy that Pedicularis debilis, with six sampled individuals, tended to be resolved as at least three species. In addition, P. kansuensis (series Verticillatae) and P. lutescens (series Lyratae) were paraphyletic.Clade 2 was resolved by all analyses (Table 2). Pedicularis pantlingii (series Furfuraceae) was resolved at the base of this clade. The remaining species corresponded to series Megalanthae, endemic to the Himalaya region. Morphologically, two samples from Xizang were identified in series Megalanthae, while they were different from two inland Chinese species P. megalantha and P. megalochilaAmong eight unresolved species, P. axillaris tended to be close to clade 3, P. batangensis to clade 1 or 4, while the systematic positions of the remaining six species (P. flexuosa, P. lachnoglossa, P. mollis, P. moupinensis, P. petelotii and P. salviiflora) are isolated (Fig. 1). Conservatively, these eight unresolved species are not treated as independent clades in this study. All eight are endemic to the Himalaya-Hengduan Mountains. Comparing them with the large clades 1, 3, 5 and 7, we suggest that the MRCAs of these eight species might not have experienced rapid radiation in the Himalaya-Hengduan Mountains, or else their relatives may have become extinct during the recent radiation, or be not yet sampled. Five unresolved species (P. batangensis, P. lachnoglossa, P. mollis, P. moupinensis, and P. salviiflora) belong to monotypic series [33], suggesting that the recently derived relatives might be extinct, or recent speciation might not have happened. Excluding P. axillaris and P. lachnoglossa with short (stem) branch lengths, the long (stem) branch lengths of the remaining six opposite-/whorled-leaved species indicate that they may have been derived at an early stage of the rapid radiation of Pedicularis. Due to the backbone of the tree being weakly supported, molecular dating may misinterpret their evolutionary histories. To improve phylogenetic resolution of the backbone, more DNA markers or next generation sequencing data should be applied. (Source: bmcplantbiol.biomedcentral.com)

 

 

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