Herbarium specimens are an important source of DNA for plant research but current sampling methods require the removal of material for DNA extraction. This is undesirable for irreplaceable specimens such as rare species or type material. Here I present the first non-destructive sampling method for extracting DNA from herbarium specimens. DNA was successfully retrieved from robust leaves and/or stems of herbarium specimens up to 73 years old.

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Two species of Coprosma (Rubiaceae) J.R.Forst. & G.Forst. are described from the island of Maui of the Hawaiian Archipelago. A newly described taxon, Coprosma cordicarpa J.Cantley, Sporck-Koehler, & M.Chau, sp. nov. is locally common in medium to high elevation dry forests and shrublands of leeward East Maui. The second taxon is resurrected from the synonymy of Coprosma foliosa A.Gray as Coprosma stephanocarpa Hillebr. and occurs in mesic to wet rainforests of both East and West Maui. Both taxa are segregated from Coprosma foliosa, with which they share similar morphological characters. A conspicuous and persistent calyx of the fruit and various floral characters most easily differentiate both taxa from other Hawaiian taxa. The newly described Coprosma cordicarpa is further distinguished from Coprosma stephanocarpa by a central constriction of the fruit with a depressed apex, which gives it a characteristic heart shape. Furthermore, the taxa are largely separated phenologically, ecologically, and geographically. Descriptions, conservation status, and specimens examined for the new species are included.

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Alien plants are a pervasive environmental problem, particularly on islands where they can rapidly transform unique indigenous ecosystems. However, often it is difficult to confidently determine whether a species is native or alien, especially if establishment occurred before historical records. This can present a management challenge: for example, should such taxa be eradicated or left alone until their region of origin and status are clarified? Here we show how combining palaeoecological and historical records can help resolve such dilemmas, using the tree daisy Olearia lyallii on the remote New Zealand subantarctic Auckland Islands as a case study. The status of this tree as native or introduced has remained uncertain for the 175 years since it was first discovered on the Auckland Islands, and its appropriate management is debated. Elsewhere, O. lyallii has a highly restricted distribution on small sea bird-rich islands within a 2° latitudinal band south of mainland New Zealand. Analysis of palaeoecological and historical records from the Auckland Islands suggest that O. lyallii established there c. 1807 when these islands were first exploited by European sealers. Establishment was facilitated by anthropogenic burning and clearing and its subsequent spread has been slow, limited in distribution and probably human-assisted. Olearia lyallii has succeeded mostly in highly disturbed sites which are also nutrient enriched from nesting sea birds, seals and sea spray. This marine subsidy has fuelled the rapid growth of O. lyallii and allowed this tree to be competitive against the maritime communities it has replaced. Although endemic to the New Zealand region, our evidence suggests that O. lyallii is alien to the Auckland Islands. Although such 'native' aliens can pose unique management challenges on islands, in this instance we suggest that ongoing monitoring with no control is an appropriate management action, as O. lyallii appears to pose minimal risk to ecological integrity.

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Fruit phenotypes are often hypothesised to be affected by selection by frugivores. Here, we tested two hypotheses concerning frugivore-fruit interactions from the perspective of fruit colours. We measured the spectral properties of 26 fruits and the associated leaves of plants from 2 islands in New Zealand. Visual observations were also performed to record the birds that fed on the fruits. First, we tested the fruit-foliage hypothesis, where fruit colours are assumed to be evolutionarily constrained by their own leaf colour to maximise colour contrast and fruit conspicuousness. We ran a null model analysis comparing fruit colour contrast using an avian eye model. Second, we tested the frugivore specificity hypothesis, where specific fruit colours are thought to be connected with a specific bird frugivore. We performed a regression on the number of bird visits against the fruit colour in tetrahedral colour space based on an avian eye calculation using Mantel's test. The results show that fruit colours are not constrained by their own leaf colours. There is also no relationship or pattern suggesting a link between a specific fruit colour and specific bird visitors. We suggest that although fruit colour is one of the most highly discussed components, it is not the most important single deciding factor in frugivore fruit selection.

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Background and aims Badnaviruses and their host-integrated DNA occur in tropical crops and a few northern temperate species. Following the discovery of a badnavirus on a subantarctic island with floristic links to New Zealand, we postulated that badnaviruses exist in the New Zealand flora. Badnavirus reverse transcriptase (RT) sequences consist of variable regions flanked by highly conserved regions. This study used RT sequences to detect and characterize badnavirus sequences in the New Zealand flora and to investigate their utility for the study of broader aspects of plant biology. Methodology Molecular diversity of RT sequences was analysed using polymerase chain reaction and denaturing gradient gel electrophoresis (DGGE). In a study of the genus Melicytus, internal transcribed spacer (ITS) sequences were compared with the RT data. Principal results No freely replicating badnaviruses were detected but more than half of the species (37/60) contained RT sequences. Phylogenetic analysis of 21 RT sequences formed monophyletic groups distinct from other species and from badnaviruses. No frameshift mutations occurred in any of the sequences translated in silico. More detailed study of the genus Melicytus indicated broader applications for our approach. Analysis of RT sequences revealed the presence of a previously unrecognized species (confirmed using ITS). Inheritance of DGGE profiles by Melicytus ramiflorus seedlings suggested that this species may undergo apomixis. Conclusions The presence of integrated badnavirus sequences in a wide range of taxa from this Southern Hemisphere flora indicates that these sequences may be common in many temperate regions. Potential to activate viruses from these sequences should be considered when placing these species in tissue culture or under other forms of abiotic or genomic stress. Analysis of endogenous RT sequences shows potential for the study of systematics, phylogenetics and plant reproductive biology.

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