New chromosome counts in New Zealand species ofPlantago(Plantaginaceae)

Abstract

Polyploidy is common in the widespread genus Plantago, and might be especially important in the evolutionary history of native New Zealand species of the genus. To further understanding of native New Zealand Plantago, mitotic and meiotic chromosome counts are reported from 58 individuals representing most native species and subspecies, and one introduced species, complementing previous studies by extending the number of individuals and the geographic range of taxa counted. Previous counts were confirmed for most Plantago lanigera (2n 0 2x012), all P. raoulii, P. spathulata subsp. spathulata, P. spathulata subsp. picta, P. triandra subsp. triandra and P. triandra subsp. masoniae (2n 0 8x 0 48), most P. unibracteata (2n 0 10x 0 60), and all P. sp. 'Sylvester' (2n 0 16x 0 96). Novel counts include 2n 0 12x 0 72 for four individuals identified as P. unibracteata, and 2n 0 48 for four individuals from Sugarloaf Pass, South Island, referred to here as P. aff. spathulata. One of the eight naturalized species, P. major, was diploid with 2n 0 12. These results, together with other studies, suggest that all native New Zealand Plantago have a base chromosome number of x 0 6 and most polyploids are allopolyploids.

Testing species limits of New ZealandPlantago(Plantaginaceae) using internal transcribed spacer (ITS) DNA sequences

“…Plantago lanigera from the Eyre Mountains, in contrast, is closest to P. paradoxa and P. raoulii. It is possible that we have misidentified these individuals and they are not in fact P. lanigera or P. novae-zelandiae; four individuals from this population have been shown to be hexaploid (2n 048), which would suggest this is the case (Murray et al 2010). Their unexpected placements in the ML and neighbour-net analyses may also be a result of complex history perhaps involving hybridization.…”

“…P. sp. 'Sylvester' has a chromosome number of 2n096, whereas both P. spathulata and P. raoulii have chromosome numbers of 2n 048 (Groves & Hair 1971;Murray et al 2010). The individuals of P. sp.…”

“…The present study contributes to a revision of the New Zealand species of Plantago by complementing morphological and chromosomal analyses already undertaken (e.g. Groves & Hair 1971;Spence & Sykes 1989) and those currently in progress (HM Meudt unpublished data; Murray et al 2010). …”

“…Both forms can be found in coastal regions and at altitudes of up to 1500 m. In addition, another undescribed but tag-named entity, P. sp. 'Sylvester' (Druce 1993), may be a species of polyploid origin with 2n096 (Groves & Hair 1971;Murray et al 2010). The single individual of P. sp.…”

“…picta (endemic to the coastal North Island regions of the Poverty Bay region and East Cape). These were previously treated as two species (P. spathulata and P. picta; Table 1) and both have the same chromosome number of 2n 048 (Groves & Hair 1971;Murray et al 2010). Separation of the two entities was based on morphological characters, i.e.…”