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Improving biodiversity conservation in fragmented agricultural landscapes has become an important global issue. Vegetation at the patch and landscape-scale is important for species occupancy and diversity, yet few previous studies have explored multi-scale associations between vegetation and community assemblages. Here, we investigated how patch and landscape-scale vegetation cover structure woodland bird communities. We asked: (1) How is the bird community associated with the vegetation structure of woodland patches and the amount of vegetation cover in the surrounding landscape? (2) Do species of conservation concern respond to woodland vegetation structure and surrounding vegetation cover differently to other species in the community? And (3) Can the relationships between the bird community and the woodland vegetation structure and surrounding vegetation cover be explained by the ecological traits of the species comprising the bird community? We studied 103 woodland patches (0.5 - 53.8 ha) over two time periods across a large (6,800 km2) agricultural region in southeastern Australia. We found that both patch vegetation and surrounding woody vegetation cover were important for structuring the bird community, and that these relationships were consistent over time. In particular, the occurrence of mistletoe within the patches and high values of woody vegetation cover within 1,000 ha and 10,000 ha were important, especially for bird species of conservation concern. We found that the majority of these species displayed similar, positive responses to patch and landscape vegetation attributes. We also found that these relationships were related to the foraging and nesting traits of the bird community. Our findings suggest that management strategies to increase both remnant vegetation quality and the cover of surrounding woody vegetation in fragmented agricultural landscapes may lead to improved conservation of bird communities.

Angiosperms that morphologically and physiologically attach to other flowering plants by means of a haustorium have evolved 12 times independently resulting in 292 genera and ca. 4750 species. Although hemiparasites predominate, holoparasitism has evolved in all but two clades, Cassytha (Lauraceae) and Krameria (Krameriaceae). Santalales contains the largest number of genera (179) and species (2428) among the 12 parasitic plant lineageswhereas Orobanchaceae is the largest single family with 102 genera and over 2100 species. This review presents the current state of knowledge on the molecular phylogenetic relationships among all clades of parasitic angiosperms. These methods have been particularly important in revealing the closest non-parasitic relatives of holoparasites, plants that exhibit reduced morphologies, increased substitution rates, and frequent horizontal gene transfers, all of which confound phylogenetics. Although comprehensive molecular phylogenies are still lacking for many of the large genera, nearly complete generic level sampling exists, thus allowing unprecedented understanding of the evolutionary relationships within and among these fascinating plants.

The mitochondrial genomes of flowering plants are characterized by an extreme and often perplexing diversity in size, organization, and mutation rate, but their primary genetic function, in respiration, is extremely well conserved. Here we present the mitochondrial genome of an aerobic parasitic plant, the mistletoe Viscum scurruloideum . This genome is miniaturized, shows clear signs of rapid and degenerative evolution, and lacks all genes for complex I of the respiratory electron-transfer chain. To our knowledge, this is the first report of the loss of this key respiratory complex in any multicellular eukaryote. The Viscum mitochondrial genome has taken a unique overall tack in evolution that, to some extent, likely reflects the progression of a specialized parasitic lifestyle. Despite the enormous diversity among parasitic angiosperms in form and structure, life-history strategies, and plastid genomes, little is known about the diversity of their mitogenomes. We report the sequence of the wonderfully bizarre mitogenome of the hemiparasitic aerial mistletoe Viscum scurruloideum . This genome is only 66 kb in size, making it the smallest known angiosperm mitogenome by a factor of more than three and the smallest land plant mitogenome. Accompanying this size reduction is exceptional reduction of gene content. Much of this reduction arises from the unexpected loss of respiratory complex I (NADH dehydrogenase), universally present in all 300+ other angiosperms examined, where it is encoded by nine mitochondrial and many nuclear nad genes. Loss of complex I in a multicellular organism is unprecedented. We explore the potential relationship between this loss in Viscum and its parasitic lifestyle. Despite its small size, the Viscum mitogenome is unusually rich in recombinationally active repeats, possessing unparalleled levels of predicted sublimons resulting from recombination across short repeats. Many mitochondrial gene products exhibit extraordinary levels of divergence in Viscum , indicative of highly relaxed if not positive selection. In addition, all Viscum mitochondrial protein genes have experienced a dramatic acceleration in synonymous substitution rates, consistent with the hypothesis of genomic streamlining in response to a high mutation rate but completely opposite to the pattern seen for the high-rate but enormous mitogenomes of Silene . In sum, the Viscum mitogenome possesses a unique constellation of extremely unusual features, a subset of which may be related to its parasitic lifestyle.

Explosive diversification is widespread in eukaryotes, making it difficult to resolve phylogenetic relationships. Eudicots contain c. 75% of extant flowering plants, are important for human livelihood and terrestrial ecosystems, and have probably experienced explosive diversifications. The eudicot phylogenetic relationships, especially among those of the Pentapetalae, remain unresolved. Here, we present a highly supported eudicot phylogeny and diversification rate shifts using 31 newly generated transcriptomes and 88 other datasets covering 70% of eudicot orders. A highly supported eudicot phylogeny divided Pentapetalae into two groups: one with rosids, Saxifragales, Vitales and Santalales; the other containing asterids, Caryophyllales and Dilleniaceae, with uncertainty for Berberidopsidales. Molecular clock analysis estimated that crown eudicots originated c. 146 Ma, considerably earlier than earliest tricolpate pollen fossils and most other molecular clock estimates, and Pentapetalae sequentially diverged into eight major lineages within c. 15 Myr. Two identified increases of diversification rate are located in the stems leading to Pentapetalae and asterids, and lagged behind the gamma hexaploidization. The nuclear genes from newly generated transcriptomes revealed a well-resolved eudicot phylogeny, sequential separation of major core eudicot lineages and temporal mode of diversifications, providing new insights into the evolutionary trend of morphologies and contributions to the diversification of eudicots.

Background - Parasitic plants are functionally specialized to acquire at least some essential resources from other plants via specialized organs called haustoria. Parasitism evolved 12 times independently in the evolution of angiosperms of which approximately 1% (4500 species) are parasitic. Not only are parasitic plants diverse in terms of evolutionary origins but also in terms of their physiological functioning and ecological behaviour. Methods - Here, I review the importance of principal functional traits which underlie the physiology and ecology of individual parasitic plants. These include the ability to perform photosynthesis, anatomical details of the vascular connection to the host determining the quality of resources acquired from the host, location of the haustoria on the host, which is closely connected with the parasite life form, and the mode of germination (either triggered by environmental condition or induced by presence of host roots). Results and conclusions - Based on the distribution of all these traits in parasitic plants, I introduce their functional classification into root hemiparasites, root holoparasites, stem parasites and endophytic parasites. In addition to the classification, I also present an evolutionary hypothesis explaining the evolution of advanced parasitic plant forms from root hemiparasites. This hypothesis is based on ecological constraints from which the parasites are released with increasing ability to acquire resources from the host. This evolutionary process also implies increasing host specificity which imposes new constraints on the ability to establish host connection. This explains the evolutionary stability of photosynthetic hemiparasites and their species richness which is one order of magnitude higher than that of holoparasites.

Premise of the study. Recent analyses employing up to five genes have provided numerous insights into angiosperm phylogeny, but many relationships have remained unresolved or poorly supported. In the hope of improving our understanding of angiosperm phylogeny, we expanded sampling of taxa and genes beyond previous analyses. Methods: We conducted two primary analyses based on 640 species representing 330 families. The first included 25260 aligned base pairs (bp) from 17 genes (representing all three plant genomes, i. e., nucleus, plastid, and mitochondrion). The second included 19846 aligned bp from 13 genes (representing only the nucleus and plastid). Key results: Many important questions of deep-level relationships in the nonmonocot angiosperms have now been resolved with strong support. Amborellaceae, Nymphaeales, and Austrobaileyales are successive sisters to the remaining angiosperms (Mesangiospermae), which are resolved into Chloranthales + Magnoliidae as sister to Monocotyledoneae + [Ceratophyllaceae + Eudicotyledoneae]. Eudicotyledoneae contains a basal grade subtending Gunneridae. Within Gunneridae, Gunnerales are sister to the remainder (Pentapetalae), which comprises (1) Superrosidae, consisting of Rosidae (including Vitaceae) and Saxifragales; and (2) Superasteridae, comprising Berberidopsidales, Santalales, CaryophyHales, Asteridae, and, based on this study, Dilleniaceae (although other recent analyses disagree with this placement). Within the major subclades of Pentapetalae, most deep-level relationships are resolved with strong support. Conclusions: Our analyses confirm that with large amounts of sequence data, most deep-level relationships within the angiosperms can be resolved. We anticipate that this well-resolved angiosperm tree will be of broad utility for many areas of biology, including physiology, ecology, paleobiology, and genomics.

To date molecular data have not revealed the exact phylogenetic position of Balanophoraceae in relation to hemiparasitic Santalales. To elucidate the phylogeny of Santalales and the position of Balanophoraceae, three plastid genes (matK, rbcL, accD), three nuclear genes (SSU and LSU rDNA and RPB2) and one mitochondrial gene (matR) from 197 Santalales samples (including 11 Balanophoraceae species) were analyzed with parsimony, maximum likelihood and Bayesian inference methods. Our results demonstrate that Balanophoraceae is composed of two well-supported clades: a relatively slow-evolving one including Dactylantus, Hachettea, and Mystropetalon (Mystropetalaceae) and an extremely fast-evolving one composed of the remaining Balanophoraceae s.str. Support for monophyly of the two clades was low, thus it appears holoparasitism has arisen twice independently in Santalales. These two clades appeared during a time of great change in the order (ca. 100 Ma) when several major evolutionary innovations emerged, e.g., the root hemiparasites of Santalaceae s.l., the first aerial parasites (Misodendraceae), herbaceous root parasites (Schoepfiaceae), root parasitic Loranthaceae (the ancestors of aerial parasitic mistletoes), as well as the holoparasites in Balanophoraceae and Mystropetalaceae.

Horizontal gene transfer (HGT) is frequent in parasitic plant mitochondria as a result of vascular connections established in host-parasite relationships. Recent studies of the holoparasitic plant Lophophytum mirabile (Balanophoraceae) revealed the unprecedented acquisition of a large amount of mitochondrial sequences from its legume host. We focused on a close relative, the generalist holoparasite Ombrophytum subterraneum, to examine the incidence of HGT events in the mitochondrial genome (mtDNA). The mtDNA of O. subterraneum assembles into 54 circular chromosomes, only 34 of which contain the 51 full-length coding regions. Numerous foreign tracts (totaling almost 100 kb, ~ 14% of the mtDNA), including 12 intact genes, were acquired by HGT from the Asteraceae hosts. Nine chromosomes concentrate most of those regions and eight are almost entirely foreign. Native homologs of each foreign gene coexist in the mtDNA and are potentially functional. A large proportion of shorter regions were related to the Fabaceae (a total of ~ 110 kb, 15.4%), some of which were shared with L. mirabile. We also found evidence of foreign sequences donated by angiosperm lineages not reported as hosts (Apocynaceae, Euphorbiaceae, Lamiaceae, and Malvales). We propose an evolutionary hypothesis that involves ancient transfers from legume hosts in the common ancestor of Ombrophytum and Lophophytum followed by more recent transfer events in L. mirabile. Besides, the O. subterraneum mtDNA was also subjected to additional HGT events from diverse angiosperm lineages, including large and recent transfers from the Asteraceae, and also from Lamiaceae.Key messageThe O. subterraneum mtDNA harbors foreign mitochondrial regions from diverse angiosperms, including 14 and 15% acquired from host lineages Asteraceae and Fabaceae. Twelve intact foreign genes coexist with native homologs.

Purpose Endemic to Noongar Country of southwestern Australia, the charismatic and much-loved mistletoe, Nuytsia floribunda (Labill.) R.Br. ex G.Don ( Munjee / Moodjar in Noongar language), was the subject of a 2010 review which explored aspects of its cultural importance and botanical attributes based largely on early colonial accounts and scientific findings. Our purpose was to apply cross-cultural methods to review and update findings reported by Hopper ( 2010 ). Methods We have recently explored this iconic species through a collaborative Elder-led, cross-cultural process, largely through oral accounts of contemporary Merningar Noongar knowledge holders. Results We record previously unpublished insights relating to Nuytsia floribunda , and longheld Noongar custom relating to its conservation, use and multi-faceted relationships with southwestern Australia’s First Nations peoples. We present Noongar- and Western science-derived knowledge relating to the physiology, ecology and evolution of this species. Conclusion The unique biology, ingenuity and physical prominence of Nuytsia floribunda has been recognised in Noongar lore for millennia. We suggest it as a valuable teacher and exemplar of prosperous survival in old, climatically-buffered, infertile landscapes and to this end, should be widely celebrated.

Premise of the Study The sandalwood order (Santalales) includes members that present a diverse array of inflorescence types, some of which are unique among angiosperms. This diversity presents not only interpretational challenges but also opportunities to test fundamental concepts in plant morphology. Here we used modern phylogenetic approaches to address the evolution of inflorescences in the sandalwood order. Methods Phylogenetic analyses of two nuclear and three chloroplast genes were conducted on representatives of 146 of the 163 genera in the order. A matrix was constructed that scored nine characters dealing with inflorescences. One character, “trios”, that encompasses any grouping of three flowers (i.e., both dichasia and triads) was optimized on samples of the posterior distribution of trees from the Bayesian analysis using BayesTraits. Three nodes were examined: the most recent common ancestors of (A) all ingroup members, (B) Loranthaceae, and (C) Opiliaceae, Santalaceae s.l., and Viscaceae. Key Results The phylogenetic analysis resulted in many fully resolved nodes across Santalales with strong support for 18 clades previously named as families. The trios character was not supported for nodes A and C, whereas it was supported for node B where this partial inflorescence type is best described as a triad. Conclusions Essentially every major inflorescence type can be found in Santalales; however, the dichasium, a type of partial inflorescence, is rarely seen and is not plesiomorphic for the order. In the family Erythropalaceae, inflorescences are mostly in small, axillary fascicles or cymes. Successive families show both cymose and racemose types and compound systems (e.g., thyrses). Inflorescences in Amphorogynaceae and Viscaceae are not dichasial and in general are difficult to compare to “standard” inflorescences.