The year 2010 was declared as the International Year of Biodiversity by The United Nations, under the Convention on Biological Diversity. One of the major events, in October, was the 10th Conference of the Parties to the Convention (COP 10) held in Nagoya, Japan, at which a new Strategic Plan (consisting of 20 targets) for the next ten years, aimed at reducing the current pressures on biodiversity and taking urgent action to save and restore nature, was approved. In addition, a new protocol on access and benefit sharing (ABS) was agreed and new resources were pledged to bring the agreements to life (IUCN, 2010a).
Also considered and agreed at COP 10 were proposals for a consolidated update of the Global Strategy for Plant Conservation (GSPC; http://plantsfortheplanet.files.wordpress.com/2010/11/cop-10-l-19-en-3.pdf) for the period 2011-2020. Based on the previous GSPC, the new version again includes 16 targets organized under five objectives, with a main focus on higher plants and other well described groups such as bryophytes and pteridophytes, but allowing governments and other stakeholders to consider conservation strategies for e.g. algae and fungi (IUCN, 2010b). Objectives I (Plant diversity is well understood, documented and recognized; Targets 1-3) and II (Plant diversity is urgently and effectively conserved; Targets 4-10) are the objectives most closely related to the subject matter covered by this journal, and here I present some ideas concerning Targets 1, 2, 7 and 8 and provide some examples of how botanical research is contributing to an increased understanding of the plant world and to the conservation of the species involved.
The aim of Target 1 is an online flora of all known plants. This is a major undertaking as, despite the long history of documentation and description of plants, remarkable new discoveries are still being made. Some newly described species are from relatively poorly studied groups, but some are the more surprising because they belong to well studied groups such as palms and carnivorous plants or they are minor crops or crop wild relatives. Each year the International Institute for Species Exploration announces the Top 10 New Species (of animals, plants and other organisms) for the preceding year (http://species.asu.edu/Top10) and this list provides good examples of such surprising discoveries. Two plants were included on the list for 2009 (which appeared in 2010): a spectacular new species of pitcher plant from the Philippines, Nepenthes attenboroughii A.S.Rob., S.McPherson & V.B.Heinrich (Nepenthaceae; Robinson et al., 2009) and a yam which is harvested locally in Madagascar but was previously undescribed, Dioscorea orangeana Wilkin (Dioscoreaceae; Wilkin et al., 2009). The ‘suicide palm’Tahina spectabilis J.Dransf. & Rakotoarin. (Arecaceae; Dransfield et al., 2008) and a caffeine-free coffee from Cameroon, Coffea charrieriana Stoff. & F.Anthony (Rubiaceae; Stoffelen et al., 2008) featured on the list for the previous year.
New discoveries and scientific results are also leading to the recognition of new genera and higher level taxa. Recently described genera of angiosperms include Tahina J.Dransf. & Rakotoarin. (Arecaceae; Dransfield et al., 2008), Kuhlmanniodendron Fiaschi & Groppo (Achariaceae; Fiaschi & Groppo, 2008), Killickia Bräuchler, Heubl & Doroszenko (Lamiaceae; Bräuchler et al., 2008) and Amphistemon Groeninckx and Thamnoldenlandia Groeninckx (both Rubiaceae; Groeninckx et al., 2010). These and other discoveries indicate that there is still work to be done in this area, particularly in biodiversity hotspots such as Madagascar and Brazil where several of these novelties were found.
Increased understanding of the phylogenetic relationships of angiosperms in recent years has led to a widely held consensus on the families and orders that should be recognized (APG II, 2003; APG III, 2009), but even since the publication of the latest version of the Angiosperm Phylogeny Group classification in 2009, new evidence has emerged to allow some of the taxa incertae sedis to be placed on the basis of molecular phylogenetic studies. Previously thought to be related to Rafflesia R.Br. and some other parasitic plants, Apodanthaceae, a family of parasitic plants, have been shown to belong to Cucurbitales (Filipowicz & Renner, 2010). Petenaea Lundell, an enigmatic genus from northern Central America treated as incertae sedis in APG III (2009) and previously considered to be a member of Elaeocarpaceae or Tiliaceae, has been placed in a new family Petenaeaceae (Christenhusz et al., 2010) as the fourth family of Huerteales, an order itself only relatively recently described (Doweld, 2001) and then recognized with a broader circumscription (Dipentodontaceae, Gerrardinaceae and Tapisciaceae; Worberg et al., 2009). Such higher level findings are likely to become less frequent, but many species remain to be found and described.
These types of findings are not limited to the angiosperms, and research into lichens, bryophytes, ferns and gymnosperms is also revealing new or unexpected patterns of relationships and leading to description of new taxa. For example, new genera (e.g. Lehtonen et al., 2010) and species (e.g. Kessler, 2008; Rouhan et al., 2008; Yesilyurt, 2008; Christenhusz, 2010) of ferns and new species of lichens (Aptroot, 2008), mosses (e.g. Cano & Gallego, 2008; Jiménez & Cano, 2008) and cycads (e.g. Singh & Radha, 2008; Taylor, Haynes & Holzman, 2008; Vovides et al., 2008) are still being described.
Parasitic plants pose problems in producing a stable classification as they often have reduced morphology and genomes (e.g. Fay et al., 2010). As mentioned above, Apodanthaceae have recently been placed, leaving only Cynomoriaceae, also parasitic, as a family incertae sedis in APG III. Among the parasitic plants the relationships of which are understood, Santalales still present some challenges as only seven families are recognized in APG III (2009), whereas Nickrent et al. (2010) have recently presented an alternative treatment of Santalales, with 18 families, including seven for the taxa comprising Santalaceae sensu APG III. Of these 18 families, four (Amphorogynaceae, Cervantesiaceae, Comandraceae and Nanodeaceae) were newly described by Nickrent et al. (2010). Whether these will be taken up more widely remains to be seen. At the generic level, there are also some unresolved problems relating to parasitic plants, including generic delimitation in tribe Thesieae Reichenb. (Santalaceae; Moore, Verboom & Forest, 2010).
Many other groups of plants also pose problems at the generic level. Well known genera such as Gnidia L. (Thymelaeaceae) have been shown to be paraphyletic with respect to several other long-recognized genera (Beaumont et al., 2009). Combretum Loefl. and Terminalia L. (Combretaceae) in their current circumscription have also been shown to have other genera embedded within them (Maurin et al., 2010). Difficult, sometimes politically or geographically driven, decisions will have to made in these cases. Should the paraphyletic genera be split to allow the embedded genera to be recognized or should a wider generic circumscription be used? Questions such as this will need to be answered before an agreed list of all plants can be developed as the basis for an online flora.
The aim of Target 2 is an assessment of the conservation status of all known plant species. Like Target 1, this represents a major, but laudable, undertaking. Much work has taken or is taking place around the world, and a major step was taken when the Royal Botanic Gardens, Kew, with the Natural History Museum, London and the International Union for Conservation of Nature (IUCN), recently announced the completion of a global analysis of extinction risk for plants. The project, entitled Sampled Red List Index for Plants, provides a major baseline for plant conservation and is the first time that the true extent of the threat to the estimated 380,000 plants is known (Royal Botanic Gardens, Kew, 2010). This index will also provide relevant background information for Targets 7 and 8 of the GSPC (aimed at conserving ≥75% of threatened plants in situ and ex situ, respectively). For Target 2, there is a need for a consistent approach to the application of IUCN Red List Criteria, and in some cases, this appears to be lacking. For example, Munzinger, McPherson & Lowry (2008) raised concerns about inconsistencies in the assessment of the New Caledonian flora and called for a reassessment of the ratings for this entire, highly endemic flora.
Effective conservation in situ and ex situ (Targets 7 and 8) involves a knowledge of various aspects of the biology of the species. For example, genetic data are now being widely used to inform conservation management of rare species (e.g. Bateman, Smith & Fay, 2008; Dong et al., 2008; Rich, McDonnell & Lledó, 2008; Chung et al., 2009; González-Pérez et al., 2009; Rodriguez-Gacio et al., 2009; Micheneau et al., 2010) and studies in other areas including seed germination and seed storage (e.g. Commander et al., 2009; Turner et al., 2009; Gale et al., 2010; Hay et al., 2010) and pollination/reproductive biology (e.g. Schlüter et al., 2009; Simbaña & Tye, 2009) also play an important role in conservation. Declines in pollinators have been identified as a particular concern in groups with specialized pollination syndromes. Micheneau, Johnson & Fay (2009), for example, stated:
Highly specialized pollination interactions, such as those exemplified by orchids, are highly vulnerable to changes in populations and habitats. As Darwin pointed out while the pollinating sphingid of A. sesquipedale was still undiscovered: ‘If such great moths were to become extinct in Madagascar, assuredly the Angræcum would become extinct’ (Darwin, 1862). Once again, Darwin led the way in drawing this important connection between evolutionary studies and the ‘real-world’ problem of conservation. This is especially relevant today because of the present context of pollinator decline as a result of habitat loss and climate change.
We live in worrying times, with climate change and other factors threatening the continued existence of the biodiversity that surrounds us and upon which we depend for our own survival. Many plants depend on a complex web of other organisms, including vertebrate and invertebrate pollinators (Micheneau et al., 2009), fungal symbionts (Wickett & Goffinet, 2008; Imhof & Sainge, 2008) and, in some cases [notably carnivorous plants (Chase et al., 2009) and parasites (Fay et al., 2010)], other plants and animals for their sustenance. The decisions taken at COP 10 in Japan are internationally significant and important: let us hope that they have the desired effect of halting loss of biodiversity, so that these complex webs of interactions will survive and continue to fascinate and to secure life on earth.