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In this study, the complete chloroplast genome sequence of Podocarpus imbricatus (Podocarpaceae) was determined. Like other chloroplast genomes in conifers, the Podocarpus imbricatus genome did not have typical quadripartite structure. The genome was 133,816 bp in length, containing 118 unique genes (82 protein-coding genes, 32 tRNA genes and four rRNA genes). The overall GC content of the genome is 37.23%. A phylogenetic tree based on 56 chloroplast genes showed that Podocarpaceae was clustered with Araucariaceae. In addition, all the Podocarpaceae species analyzed in this study formed a monophyletic clade.

Solfatara fields, areas surrounding fumaroles (volcanic vents) near the hot springs or volcanoes, are characterized by severe environmental conditions such as low soil pH and high aluminum contents. Fimbristylis dichotoma subsp. podocarpa is an endangered plant distributed in solfatara fields of Kyushu, western Japan. This species is known to form stands in sites closed to fumaroles where another solfatara plant Miscanthus sinensis do not colonize. We conducted field survey and culture experiments to test the hypothesis that F. dichotoma has higher tolerance to low pH and high aluminum conditions than M. sinensis, which corresponds to the distribution pattern of the two species. In the study site of Myoban Hot Spring, Oita Prefecture, rhizosphere soils of F. dichotoma showed lower pH and higher aluminum contents than those of M. sinensis. The culture experiment showed that germination of F. dichotoma was not inhibited even at pH 2, whereas significant decline in germination (%) was observed in M. sinensis. However, because of the low germination (%) of F. dichotoma, the values of the two species were similar at pH 2. In the pot culture, seedling growth of M. sinensis was suppressed at the aluminum concentrations tested (400 mg AlCl3 L−1). Conversely, no significant decline in the seedling growth was observed in F. dichotoma at the same aluminum levels. Considering soil conditions in the field, we concluded that that the difference in the tolerance to aluminum between the two species played a significant role in determining their distribution pattern. [ABSTRACT FROM AUTHOR]

Well preserved fossil wood in the form of tree stumps, logs, branches, roots and occasionally bark is common throughout the Gore Lignite Measures, southern New Zealand. The main objective of the present study is to identify the range of forest trees present using anatomical features such as: distinct growth rings; presence or absence of axial parenchyma; uniseriate to triseriate, opposite to alternate, separate or contiguous tracheid pitting; and taxodioid, cupressoid and araucarioid cross-field pitting. Specimens of silicified and lignified wood are described and illustrated from four localities within the Late Oligocene-Early Miocene Gore Lignite Measures, Southland: Newvale Coal Mine; Mataura Coal Mine; Cosy Dell Coal Pit; and Bennett’s Pit. The fossil wood specimens include examples of Araucariaceae, Cupressaceae and Podocarpaceae. Three specimens from Newvale Mine resemble Araucariaceae, while one is assigned to Cupressaceae. Cosy Dell Coal Pit preserved branches of Podocarpaceae. Large stumps and branches preserved at the Mataura Coal Mine are identified as Cupressaceae and Podocarpaceae. Wood recovered from Bennett’s Pit resembles either Cupressaceae or Podocarpaceae. Araucariaceae, in the form of Agathis Salisb. trees are today restricted to the northern North Island. Cupressaceae and Podocarpaceae are still extant in modern forests throughout New Zealand. So far, no angiosperm wood has been recognised from the lignite deposits. The forests in which these trees lived were in or near oligotrophic swamps on a deltaic plain. Identification of samples of fossil wood provides new data that can be used to reconstruct the forest vegetation of the Gore Lignite Measures. [ABSTRACT FROM AUTHOR]

A new 12,17-cyclo-labdane diterpenoid, podoimbricatin C (1), along with 15 known compounds was isolated from the twigs of Dacrycarpus imbricatus. Their structures were elucidated by means of extensive spectroscopic analysis. Compound 1 is the second example of the unusual 12,17-cyclo-labdane diterpenoids. It showed no inhibitory effects against five human tumour lines (HL-60, SMMC-7721, A-549, MCF-7 and SW-480). [ABSTRACT FROM AUTHOR]

Premise of the Study: Nuclear microsatellite markers were developed for population genetic analysis of the threatened paleoendemic conifer Pherosphaera hookeriana (Podocarpaceae). Methods and Results: Fifteen variable loci were identified showing one to 13 alleles per population, with seven loci displaying at least four alleles in all populations, and the average number of alleles per locus ranging from 4.80 to 5.93 per population. Levels of observed heterozygosity per locus varied from 0.00 to 0.91, while average heterozygosity across all loci varied from 0.54 to 0.63 between populations. All loci also amplified in the endangered congener P. fitzgeraldii, but only five of the loci had more than one allele. Conclusions: These 15 loci are the first microsatellite markers developed in the genus Pherosphaera. These loci will be useful for investigating the species' extant genetic diversity and structure, the impact of past environmental change, and the significance of asexual reproduction. [ABSTRACT FROM AUTHOR]

Pollen diagrams from three areas of the Kenai Lowland of Alaska demonstrate the pollen floras of the Clamgulchian Stage (∼8–2.5 Ma) of Late Miocene/Early Pliocene age. These sections, originally described based on their plant megafossils and pollen, are revisited for a more precise determination of their pollen stratigraphy. The floras from Clam Gulch on the west margin of the Kenai Lowland are compared with Clamgulchian sections of the same age on the east margin, in canyons at the head of Kachemak Bay. The results substantiate that in the Clamgulchian sections thermophile pollen types (exotic warmth-loving woody genera) represent about 2–10% of the count (and include 15 thermophile taxa), while in the earlier Homerian Stage (∼14.5–8 Ma) thermophiles are more important and more diverse (28 taxa), representing 5–15% of the count. A second difference between the Homerian and Clamgulchian is the increased diversity of herbaceous groups (such as Ranunculaceae, Urticaceae, Onagraceae, Primulaceae and others), which are few in the Homerian (∼4–5 taxa), but many in the Clamgulchian (≤15–18 taxa). These herb groups show increasing diversity near the top of the Neogene in the Alaskan flora. With a decrease in thermophiles, the Clamgulchian taxa show a transition towards a cooler climate. Pollen of the exotic gymnosperm family Podocarpaceae chiefly of the Southern Hemisphere are diverse minor elements during the entire Neogene of Alaska. These consistent elements may represent resident associates of the hardwood forests in southern Alaska as the likelihood of their pollen occurrences being the result of long-distance transport seems unlikely. [ABSTRACT FROM PUBLISHER]

Ten diterpenoids including three new abietanes (1–3) were isolated from the twigs and needles ofPodocarpus imbricatus, an endangered conifer growing in a Cantonese garden. The new structures were established by means of spectroscopic methods. Among the isolates, 3β-hydroxy-abieta-8,11,13-trien-7-one (5), decandrin G (6), and 7,15-pimaradien-18-oic acid (8) showed significant anti-neuroinflammatory activities by inhibiting the overproduction of nitric oxide (NO) in lipopolysaccharide (LPS)-stimulated murine BV-2 microglial cells, with IC50values of 3.7, 11.1, and 4.5 μM, respectively. [ABSTRACT FROM PUBLISHER]

The debated vegetation response to climate change can be investigated through palynological fossil records from past extreme climate conditions. In this context, the early Eocene (53.3 to 41.2 million years ago (Ma)) is often referred to as a model for a greenhouse Earth. In the Xining Basin, situated on the Northeastern Tibetan Plateau (NETP), this time interval is represented by an extensive and well-dated sedimentary sequence of evaporites and red mudstones. Here we focus on the palynological record of the Early Eocene Climatic Optimum (EECO; 53.3 to 49.1 Ma) and study the fossil gymnosperm pollen composition in these sediments. In addition, we also investigate the nearest living relatives (NLR) or botanical affinity of these genera and the paleobiogeographic implications of their occurrence in the Eocene of the NETP. To reach our objective, we complemented transmitted light microscopy with laser scanning- and electron microscopy techniques, to produce high-resolution images, and illustrate the morphological variation within fossil and extant gymnosperm pollen. Furthermore, a morphometric analysis was carried out to investigate the infra- and intrageneric variation of these and related taxa. To place the data in context we produced paleobiogeographic maps for Phyllocladidites and for other Podocarpaceae, based on data from a global fossil pollen data base, and compare these with modern records from GBIF. We also assessed the climatic envelope of the NLR. Our analyses confirm the presence of Phyllocladidites (NLR Phyllocladus, Podocarpaceae) and Podocarpidites (NLR Podocarpus , Podocarpaceae) in the EECO deposits in the Xining Basin. In addition, a comparative study based on literature suggests that Parcisporites is likely a younger synonym of Phyllocladidites. Our findings further suggest that the Phyllocladidites specimens are derived from a lineage that was much more diverse than previously thought, and which had a much larger biogeographical distribution during the EECO than at present. Based on the climatic envelope of the NLR, we suggest that the paleoclimatic conditions in the Xining Basin were warmer and more humid during the EECO. We conclude that phylloclade-type conifers typical of the southern-temperate podocarp forests, had a northward geographical expansion during the EECO, followed by extirpation. • We studied gymnosperm pollen of early Eocene sediments in NE Tibet. • Phyllocladidites (affinity Phyllocladus) and Podocarpidites were common. • Now, Phyllocladus is restricted to temperate forests in the southern hemisphere. • Their extent into Tibet can be explained by the Early Eocene Climate Optimum. • Global cooling and continental aridification likely drove paleobiogeographic change. [ABSTRACT FROM AUTHOR]

The stepwise fragmentation of Gondwana had a lasting impact on Southern Hemisphere ecosystems, but its consequences remain difficult to ascertain without detailed knowledge of the biota colonizing the supercontinent before and during breakup. This palynological study characterizes the Early Cretaceous vegetation of the southern Perth Basin, a key location during the separation of Greater India from Western Australia. The well-preserved palynological assemblages recorded here include marine and putative freshwater dinoflagellate cysts and diverse spore and pollen associations. The palynomorphs indicate lacustrine, fluvial and estuarine depositional settings in the southern Perth Basin between the Berriasian and Hauterivian. The estuarine assemblages are characterized by rare to common marine dinoflagellate cysts, which indicate the early stages of marine deposition, conditions that later prevailed across most of the basin. The Early Cretaceous vegetation of the study area, as inferred from spores and pollen, is interpreted to consist mainly of conifer forests dominated by Araucariaceae, Podocarpaceae and Cheirolepidiaceae with an understory of ferns (Osmundaceae, Schizaeaceae) and other spore-producers (clubmosses, mosses, liverworts and hornworts). Two vegetation-types are hypothesized for the region with their distribution related to substrate characteristics and water availability: a more mesic, structurally complex, riverine forest within paleovalleys and topographic lows, and a more open forest accross the hinterland. [ABSTRACT FROM AUTHOR]

There is limited knowledge on the growth responses of coexisting conifer species to water conditions in the Andean region of South America- particularly in South-Central Chile (37°−40°S) where high temperatures and drought risk is expected to increase in the future. Here, we used wood cores from living trees and cross-sections of stumps to study the secondary growth responses to hydroclimatic environmental variables in Araucaria araucana , Austrocedrus chilensis and Prumnopitys andina , three coexisting conifers in a temperate Andean forest. The standardized tree-ring chronologies are robust and have been well replicated over the past two centuries, with an expressed population signal greater than 0.90. Our findings indicate that chronologies of Austrocedrus and Prumnopitys were quite similar, while Araucaria was almost independent. The secondary growth of Araucaria was negatively related to August precipitation and river runoff, likely due to a high probability of snow cover at high elevations in winter. In contrast, the secondary growth of Austrocedrus and Prumnopitys was positively associated with precipitation and streamflow and negatively with high maximum temperatures in two seasons, summer (December to February) and autumn (April to May). Prumnopitys growth was strongly associated with streamflow during last year´s and current year´s growing seasons. In the years 1962, 1998 and 2008 there occurred severe droughts, which were associated with growth reductions in the three conifers. Araucaria growth showed the greatest resistance to drought, while Austrocedrus was the most resilient to drought and showed the greatest ability for growth recovery after a drought. Araucaria growth showed near-constant resistance, recovery and resilience to drought during the study period, while Austrocedrus growth showed high recovery and resilience after the 1962 and 2008 droughts. Our results revealed contrasting behavior of coexisting conifers with respect to hydroclimate, which could help predict future changes in the performance of temperate Andean forests in a potentially drier and warmer climate. [ABSTRACT FROM AUTHOR]

The complete chloroplast genome sequence of Podocarpus macrophyllus was determined in this study. According to the results, the genome is 134,239 bp in length. The GC content of the whole chloroplast genome is 37.0%. The complete chloroplast genome of P. macrophyllus encodes a total of 120 genes, including 34 tRNA genes, 4 rRNA genes and 82 protein-coding genes. Like other conifers chloroplast genomes, P. macrophyllus has no inverted repeat sequences. To reveal the phylogenetic relationship of P. macrophyllus, we constructed phylogenetic trees using other species of Podocarpaceae, and the phylogenetic analysis showed that P. macrophyllus is evolutionarily closest to Podocarpus longifoliolatus. [ABSTRACT FROM AUTHOR]

Nageia fleuryi (Hickel) de Laub. 1987 belongs to the genus Nageia in the family Podocarpaceae and is distributed throughout southeast Asia, including China, Vietnam, and Cambodia. It is a plant with high economic beneficial for food and construction industries. Here, we report on the complete chloroplast (cp) genome of N. fleuryi for the first time. The complete cp genome is similar to many gymnosperm plants, however, it lacks inverted repeat regions and does not possess a typical quadripartite structure. The complete cp genome is 133,870 bp in size and the overall guanine-cytosine (GC) content was found to be 37.27%. The total number of genes is 119, including 82 protein-coding genes, 33 tRNA genes, and 4 rRNA genes. Of these, 14 genes contain one intron, two genes contain two introns, and rps12 possessed a trans-splicing mechanism. Finally, the phylogenic tree demonstrated that N. fleuryi is closely related to Nageia nagi (AB830885.1 and LC572156.1) [ABSTRACT FROM AUTHOR]

Leaf cuticle micromorphology has been cited as an important set of taxonomic characters in gymnosperms, but previous studies have largely been based on small sample sizes. The premise of this study was to understand whether external factors affect cuticular micromorphology of Podocarpaceae. Two example species, Prumnopitys andina and Podocarpus salignus, were studied. Of 21 sampled characters, nine (c.43% of the total) were visually assessed as being moderately reliable or highly reliable for taxonomic discrimination for both species, with an additional six (c.29%) being moderately reliable or highly reliable for only one or other of the example species, and six characters (c.29%) unreliable for both. Seven of the most variable stomatal characters were selected for further analysis to establish whether environmental factors affect them. The relationship between these seven stomatal characters, the environment and climate was analysed using the R ‘vegan’ package and climate data gathered from WorldClim. Our results showed that both species had larger stomata in moist and shady conditions, and a higher density of (smaller) stomata in sunny and drier conditions. An additional novel finding was the presence of stomata on the adaxial leaf surface in 46% of samples of Prumnopitys andina: the first record of adaxial stomata in this species, highlighting the necessity of studying multiple samples of a given species. In conclusion, these results indicate that larger sample sizes than have hitherto been employed in cuticle micromorphological studies are necessary to fully document the amount of phenotypic variation that exists. [ABSTRACT FROM AUTHOR]

Cryofracture of living material and fracture at room temperature of herbarium material were used to obtain cross-sections of the stomatal complexes of four species of Podocarpus (Podocarpaceae) for scanning electron microscopy. Cross-sections of the stomata of one species in Podocarpus subgenus Foliolatus section Foliolatus (Podocarpus rubens), one in Podocarpus section Globulus (Podocarpus beecherae), one in Podocarpus subgenus Foliolatus section Longifoliolatus (Podocarpus insularis) and one in subgenus Podocarpus section Australis (Podocarpus nivalis) were studied. The architecture of the stomatal complex, including the wax plug, is described. It was found that the wax plug sits high in the stomatal antechamber in Podocarpus rubens, P. beecherae and Podocarpus decipiens and about halfway up the chamber in P. nivalis. A ridge, which appears to correspond to the crease where the guard cells meet, exists on the underside of the wax plug in Podocarpus beecherae, P. decipiens and P. rubens; its presence in P. nivalis requires confirmation. In addition, ridges within the stomatal antechamber were observed when viewing the cross-sections of Podocarpus decipiens and P. rubens, the internal surface of the cuticle of P. decipiens, Podocarpus teysmannii, P. insularis and Podocarpus milanjianus, and the external surface of the cuticle of Podocarpus chinensis, Podocarpus macrophyllus and Podocarpus pilgeri. These ridges may consist of wax and be a result of epitaxis. [ABSTRACT FROM AUTHOR]

A new 5(6→7)abeo-sterol, podosterol (1), together with 20 known compounds, were isolated from the leaves ofPodocarpus fleuryi. Their structures were elucidated by means of extensive spectroscopic analysis. Podosterol was assessed for its cytotoxicity against five human tumor cell lines (HL-60, SMMC-7721, A-549, MCF-7, and SW-480), and the result showed that it had no activity. [ABSTRACT FROM AUTHOR]

The present study investigates the biomarker signatures of sediments and crude oils to infer the paleovegetation from the two petroleum systems of Assam Basin, eastern India. They are classified as the Paleocene-middle Eocene and the middle Eocene-Oligocene petroleum systems. The sediments are oil and gas prone with an early catagenetic stage of thermal evolution. Here we report tricyclic diterpanes such as rimuane, pimarane, rosane and isopimarane along with tetracyclic diterpanes: ent -beyerane, phyllocladane, kaurane from Paleocene-Eocene coal-bearing sediments and crude oils. These diterpane biomarkers attest dominant contribution from conifers, possibly from Podocarpaceae and Araucariaceae. However, diterpanes are not detected in Oligocene sediments and oils. Crude oils from both Paleocene-Eocene and Oligocene reservoirs and organic rich sediments contain angiosperm biomarkers such oleanane and related triterpanes along with bicadinane, a biomarker specific for the Dipterocarpaceae family of angiosperms. The equatorial position of India during early Paleogene along with the presence of angiosperm signatures including Dipterocarpaceae and gymnosperms reflect the emergence of tropical rainforest elements in eastern India. Absence of diterpenoids in Oligocene samples and difference in angiosperm parameters from Paleocene-Eocene samples suggests a change in source vegetation and organofacies. [ABSTRACT FROM AUTHOR]

PREMISE OF THE STUDY: The flip-leaved podocarp Retrophyllum has a disjunct extant distribution in South American and Australasian tropical rainforests and a Gondwanic fossil record since the Eocene. Evolutionary, biogeographic, and paleoecological insights from previously described fossils are limited because they preserve little foliar variation and no reproductive structures. METHODS: We investigated new Retrophyllum material from the terminal Cretaceous Lefipán, the early Eocene Laguna del Hunco, and the early/middle Eocene Río Pichileufú floras of Patagonian Argentina. We also reviewed type material of historical Eocene fossils from southern Chile. KEY RESULTS: Cretaceous Retrophyllum superstes sp. nov. is described from a leafy twig, while Eocene R. spiralifolium sp. nov. includes several foliage forms and a peduncle with 13 pollen cones. Both species preserve extensive damage from sap-feeding insects associated with foliar transfusion tissue. The Eocene species exhibits a suite of characters linking it to both Neotropical and West Pacific Retrophyllum, along with several novel features. Retrophyllum araucoensis (Berry) comb. nov. stabilizes the nomenclature for the Chilean fossils. CONCLUSIONS: Retrophyllum is considerably older than previously thought and is a survivor of the end-Cretaceous extinction. Much of the characteristic foliar variation and pollen-cone morphology of the genus evolved by the early Eocene. The mixed biogeographic signal of R. spiralifolium supports vicariance and represents a rare Neotropical connection for terminal-Gondwanan Patagonia, which is predominantly linked to extant Australasian floras due to South American extinctions. The leaf morphology of the fossils suggests significant drought vulnerability as in living Retrophyllum, indicating humid paleoenvironments. [ABSTRACT FROM AUTHOR]

Abstract< Understanding the interactive effects of fragmentation and invasive species on forest dynamics requires a long-term perspective because they are difficult to assess in the medium- to long-term using observational or experimental data alone. In such settings ecological models have an important role to play. Here we describe the implementation of a spatially explicit individual-based model (SEIBM) representing the dynamics of small forest fragments in northern New Zealand based on empirical data collected in the region. In addition, we performed a baseline analysis to determine how well the model captured podocarp-tawa forest dynamics, and compared its performance with stand structure data obtained from an unfragmented forest in northern New Zealand. We used sensitivity analysis to determine how sensitive the model was to changes in the input parameters. In addition, we simulated different scenarios under diverse management conditions to explore the model’s potential as a management tool. The model captures the stand structural characteristics of the fragments reasonably well but under-predicts stand basal area, suggesting that it does not represent the long-term suppression of some canopy tree species adequately. Although some refinement is needed to improve its performance, we believe that the model presented here is a useful tool for management purposes and for the assessment of the long term viability of forest fragments. The model can help inform managers and decision-makers regarding the long-term persistence of podocarp-tawa forest patches. [ABSTRACT FROM AUTHOR]

The world's sole 'parasitic' gymnosperm Parasitaxus usta (Podocarpaceae) is endemic to the island of Grande Terre, New Caledonia. It is a threatened species because of its limited geographic range and progressing habitat fragmentation. Here, we report a novel scale insect outbreak on a Parasitaxus sub-population from Monts Dzumac in the southern part of Grande Terre. The identity of the scale insect was determined through combining morphological and molecular methods. The field collection of scale insects and their secretions from infested Parasitaxus specimens allowed morphological identification of the superfamily Coccoidea. Subsequent genetic sequencing using CO1 markers allowed phylogenetic placement of the wax scale insects to the genus Ceroplastes (Coccoidea, Coccidae), a widespread pest genus. The identified species, C. pseudoceriferus, has not been previously recorded from New Caledonia. As Parasitaxus is already vulnerable to extinction, this new threat to its long-term survival needs to be monitored. Other New Caledonian endemic plant species are potentially at risk of this new species, although it was not observed on Falcatifolium taxoides, the host of Parasitaxus. [ABSTRACT FROM AUTHOR]

The main objective of the present work is to describe the first conifer assemblage of a mixed forest from the Danian Salamanca Formation at the Estancia Las Violetas locality (San Jorge Basin, Central Patagonia, Argentina), based on detailed descriptions of secondary xylem. Also, sedimentological description of the Estancia Las Violetas outcrops are made in order to understand the paleoenvironmental conditions under which paleocommunities developed. Six conifer woods are described and assigned to one Podocarpoxylon Gothan and three Cupressinoxylon Göppert species (including a new species). This is the first record of Patagonia forest where the conifer assemblage is dominated by Cupressinoxylon, associated with Podocarpaceae and palms (recorded as fruits), conforming a mixed forest with a floristic composition similar to present-day New Caledonia forests. Las Violetas fossil forest represent a parautochtonous community developed in a forested coastal setting, a tide-dominated estuary, at ∼51–50° S paleolatitudes of South America during the early–middle Danian. [ABSTRACT FROM AUTHOR]

A new species of Podocarpoxylon Gothan is described based on samples collected from sediments of the Río Turbio Formation. The fossil-bearing strata are lower Eocene (47-46 Mya) according to recent geochronological ages. The new species has indistinct growth ring boundaries, abundant and frequently tangentially zonate axial parenchyma, uniseriate pitting on radial walls, one half-bordered pit (= oculipore) with reduced borders and vertical aperture inclination per cross-field and medium height uniseriate rays. The new material is compared with all fossil-species of Podocarpoxylon and an inventory of all Podocarpoxylon species previously described is provided. Cross-field characters of the new species indicate affinity to the Podocarpaceae. The presence of Podocarpaceae wood augments other evidence of this family from the same stratigraphic unit. [ABSTRACT FROM AUTHOR]

A new abietane mono-norditerpenoid, nagiol A (1), along with three known diterpenoids were isolated from the leaves of Podocarpus nagi. Their structures were elucidated by means of extensive spectroscopic analysis. This is the first report of abietane mono-norditerpenoid separated from plant of the genus Podocarpus. Compound 1 was assessed for its cytotoxicity against five human tumour lines (HL-60, SMMC-7721, A-549, MCF-7 and SW-480), and the result showed that it had no activity. [ABSTRACT FROM AUTHOR]

We investigated consequences of plant-soil feedbacks (PSFs) in a tropical montane forest on Mt. Kinabalu in Borneo by measurements of light and soil conditions, ecophysiological analyses of tree seedlings, a long-term adult and seedling census, and a simple simulation model. The study plot (2.74 ha) is in a mixed conifer-broadleaf forest with 24% relative basal area of conifers. First, we investigated light and soil conditions beneath two dominant species, a conifer Dacrydium gracilis (Podocarpaceae, arbuscular mycorrhizal tree) and a broadleaf Lithocaprus clementianus (Fagaceae, ectomycorrhizal tree). The relative light intensity was marginally higher beneath Dacrydium tree crown than beneath Lithocarpus tree crown. The concentrations of inorganic nitrogen and labile phosphorus, and the nitrogen mineralization rate, were lower beneath Dacrydium than beneath Lithocarpus, suggesting that soils beneath Dacrydium were more nutrient deficient. Microscopic observations confirmed that conifer seedlings (including Dacrydium) harbored arbuscular mycorrhizal fungi. In addition, a molecular analysis showed that root-associated mycorrhizal fungal communities were clearly different between conifer and broadleaf seedlings, and consequently, nutrient acquisition capacity of seedlings may be different between them. Indeed, stable isotopic evidence suggested that Dacrydium seedlings are more efficient in inorganic nitrogen acquisition than Lithocarpus seedlings. These results predicted that the conifer seedlings would out-compete broadleaf seedlings and have a greater advantage beneath the conifer canopy. To test the possible advantage of conifer seedlings in performance, we developed hierarchical Bayesian models and estimated growth and mortality rates using the seedling census data during 2006-2012. We found that conifer seedlings performed better than broadleaf seedlings beneath Dacrydium canopy. On the other hand, broadleaf seedlings performed better than conifer seedlings beneath Lithocarpus canopy. The consequences of the PSFs for the tree community composition were investigated by developing a simple simulation model, and were compared with the results of a model without PSFs. After a 10 000-year simulation, the relative abundance of conifers with PSFs converged to 22%, which was consistent with the actual abundance; the model without effects of PSFs predicted a relative abundance of only ~10%. The results suggested that PSFs contributed to the maintenance of the conifer dominance in the tropical montane forest. [ABSTRACT FROM AUTHOR]

A new cyclopeptide, neriitide A (1) and a new lignan, neriilignan (2), along with six known compounds including two diterpenoids, three sesquiterpenoids and one sterol were isolated from the leaves of Podocarpus neriifolius. Their structures were elucidated by means of extensive spectroscopic analysis including HREIMS, 1D and 2D NMR techniques. This is the first report of cyclopeptide and lignan separated from this plant. [ABSTRACT FROM AUTHOR]

A new 5(6→7)abeo-sterol with rarely reported [6–5-6–5]-fused rings, 3β,5β,6-trihydroxyl-B-norsitostane (1), along with 10 known compounds were isolated from the twigs ofPodocarpus fleuryi. Their structures were elucidated by means of extensive spectroscopic analysis. Compound1was assessed for their cytotoxicity against five human tumour cell lines (HL-60, SMMC-7721, A-549, MCF-7 and SW-480), and the result showed that it had no activity. [ABSTRACT FROM PUBLISHER]

Species belonging to the Coryneliaceae and parasitizing Podocarpaceae hosts were collected from different locations in South Africa and studied morphologically by light microscopy and molecularly by obtaining partial nrDNA (ITS-1/5.8S/ITS-2, 18S and 28S) gene sequences. The position of the Coryneliaceae within the Eurotiomycetidae was not confirmed and a new subclass, Coryneliomycetidae, was introduced. While Eurotiomycetidae usually form cleistothecia/gymnothecia with evanescent, unitunicate asci, and Chaetothyriomycetidae mostly perithecia with bitunicate/fissitunicate to evanescent asci, Coryneliomycetidae form pseudothecial mazaedial ascomata, initially with double-walled asci with the outer layer deliquescing, resulting in passive ascospore release. The Coryneliomycetidae thus occupies a unique position in the Eurotiomycetes. Furthermore, epitypes were designated for Corynelia uberata, the type species of Corynelia (type genus of the family, order and subclass), Lagenulopsis bispora, the type species of Lagenulopsis, and Tripospora tripos the type species of Tripospora, with Lagenulopsis and Tripospora confirmed as belonging to the Coryneliaceae. Corynelia uberata resolved into three clades, one on Afrocarpus (= Podocarpus) falcatus and A. gracilior, and two clades occurring on P. latifolius, herein described as C. africana and C. fructigena. Morphologically these three species are not readily distinguishable, although they differ in spore dimensions, ascomata shape, ornamentation and DNA phylogeny. It is likely that several more species from other parts of the world are currently erroneously placed in C. uberata. [ABSTRACT FROM AUTHOR]

Podocarpus is the most dominant genus of Podocarpaceae, with higher taxonomical proximity to the Taxaceae, having numerous pharmaceutical applications, however, scarce studies dealing with the physiological and metabolic criteria of Podocarpus in Egypt were reported. Thus, the objective of this work was to assess the physiological and metabolical patterns of the different species of Podocarpus ; P. gracilior, P. elongates, P. macrophyllus and P. neriifolius. The highest terpenoids contents were reported in P. neriifolius , followed by P. elongatus , and P. macrophyllus . P. gracilior had the highest antioxidants amount, followed by P. macrophyllus , P. neriifolius and P. elongatus . From the GC/MS metabolic profiling, caryophyllene, β-cadinene, β-cuvebene, vitispirane, β-cadinene and amorphene were the most dominant metabolites in P. gracilior. β-Caryophyllene was the common in P. gracilior, P. elongatus, P. macrophyllus and P. neriifolius with an obvious fluctuation. The plant methanolic extracts have an obvious activity against the multidrug resistant bacteria; E. coli , P. aeruginosa , S. pyogenes and S. aureus , and fungi; A. fumigatus , A. flavus, A. niger and C . albicans in a concentration-dependent manner. The highest Taxol yield was assessed in the extracts of P. elongatus (16.4 μg/gdw), followed by P. macrophyllus , and P. neriifolius . The chemical identity of Taxol derived from P. elongatus was resolved by LC/MS, with molecular mass 854.6  m / z , and similar structural fragmentation pattern of the authentic one. The highest antitumor activity of P. elongatus extracted Taxol was assessed towards HCT-116 (30.2 μg/ml), HepG-2 (53.7 μg/ml) and MCF-7 (71.8 μg/ml). The ITS sequence of P. elongatus "as potent Taxol producer" was deposited on Genbank with accession #ON540734.1, that is the first record of Podocarpus species on Genbank., Competing Interests: The authors declare that they have no competing of interests., (© 2023 The Authors.)

Los bosques montanos del noroccidente peruano son formaciones vegetales que presentan una alta diversidad y endemismos. Lamentablemente, en muchos lugares están sujetos a procesos acelerados de deterioro por la deforestación y colonización, aspecto que los convierte en uno de los ecosistemas más amenazados por el hombre. Lo que ahora queda de estos bosques, alguna vez extensos, son sólo fragmentos. Los bosques montanos relictos son ecosistemas ubicados por encima de los 1000 m de altitud, en la Vertiente Occidental de los Andes. Es en estos bosques, donde se pueden encontrar especies de coníferas nativas de nuestro país, pertenecientes a la familia Podocarpaceae. Estas especies juegan un rol de suma importancia en la dinámica de estos ecosistemas tan frágiles; no obstante, debido a la calidad de sus maderas, están siendo extraídas de manera alarmante. En el noroccidente peruano existen zonas de bosques homogéneos de Podocarpáceas tal es el caso del bosque de Cachil en la provincia de Contumazá, bosque de TongodQuellahorco en la provincia de San Miguel (en los cuales predomina la especie Podocarpus oleifolius) y los bosques de San Ignacio en Cajamarca, en los que reportamos cinco especies de Podocarpáceas distribuidas en tres géneros: Podocarpus (P. oleifolius, P. macrostachys, P sprucei), Prumnopitys (P. harmsiana) y Nageia (N. rospigliosii), las cuales representan el 50% del total de especies reportadas para el Perú.

El pino romerón (Nageia rospigliosii Pilger) es una conífera tropical que crece en bosques altoandinos sobre suelos deficientes en fósforo (P). Bajo tales condiciones, las micorrizas pueden desempeñar una función importante en la nutrición de las plantas. En este trabajo se evaluó la dependencia micorrizal y la concentración foliar de fósforo en plántulas de esta especie inoculadas con Glomus aggregatum bajo distintos niveles de intensidad de luz y de disponibilidad de P en la solución del suelo, mediante un diseño experimental de parcelas divididas. Las plántulas se sometieron a tres diferentes niveles de iluminación relativa (IR) en casas de sombra que replicaban las condición del sotobosque con baja iluminación relativa (2% de IR), claros medianos o bordes de bosque con iluminación relativa media (18 % de IR) y plena exposición con IR alta. El suelo estéril recibió KH2PO4 para obtener tres niveles de concentración de P en la solución del suelo (0,002, 0,02 y 0.2 mg•L-1). La categoría de dependencia micorrizal del pino romerón fue Moderadamente Dependiente. Esta categoría de dependencia no cambió significativamente en las distintas intensidades de luz en que se desarrollaron las plántulas. El contenido foliar de P aumentó con el incremento de la concentración de P en la solución del suelo. La inoculación con G. aggregatum incrementó significativamente el contenido de P foliar a 0,002 y 0,02 mg•L-1 pero no a 0,2 mg•L-1.Nageia rospigliosii Pilger is a tropical coniferous tree from highland Andean forests, which grows in phosphorous (P) deficient soils. Under such conditions micorrhizae can perform an important function in plant nutrition. This paper evaluates the mycorrhizal dependency and leaf P concentration in seedlings of this species inoculated with Glomus aggregatum under different levels of light intensity and phosphorus availability in soil solution using a split-plot experimental design. Seedlings were grown under three levels of relative illumination (RI) in shade houses which resembled light conditions of understory with low light (2% RI), medium-sized canopy gaps or forest edges with medium RI (18% RI) and full sun exposure with high RI. After sterilization, soil received KH2PO4 to obtain three levels of P concentration in soil solution (0.002, 0.02 y 0.2 mg•L-1). Results showed that this species is “Moderately Dependant” on mycorrhizal association and that this condition was similar for plants growing under different light intensities. Foliar P increased with the increase of P concentration in soil solution. Inoculation with G. aggregatum significantly increased foliar content of P under low to moderate P in soil solution (0.002 and 0.02 mg•L-1) but not under high P concentration (0.2 mg•L-1).

O presente estudo foi desenvolvido com o objetivo de avaliar a variação dimensional das traqueídes ao longo do caule de Podocarpus lambertii Klotzsch ex Endl. Discos de madeira de três indivíduos foram retirados em diferentes alturas ao longo do caule. As amostras para o estudo da variação dimensional das traqueídes foram selecionadas no limite das camadas de crescimento e no sentido câmbio-medula. A avaliação do material, assim como sua mensuração e obtenção de imagens foram realizadas utilizando microscopia fotônica (Olympus - BX-41). Os dados obtidos foram analisados estatisticamente. No sentido radial houve um aumento no comprimento das traqueídes em direção medula-câmbio, sendo significativa a diferença entre as camadas de crescimento pela análise do teste "t-student". Houve uma variação mínima no que se refere ao diâmetro das traqueídes e a análise da espessura da parede celular revelou que não houve variação. São apresentadas figuras e tabelas onde são discutidos os resultados obtidos com trabalhos que fazem à mesma abordagem e os fatores que podem influenciar a variação das traqueídes no sentido radial e ao longo da árvore.Variation in tracheid size in the stem of Podocarpus lambertii Klotzsch ex Endl. was investigated. Wood samples were taken from three individuals at three different stem heights. From these samples, subsamples were selected at the limit of the growth layers, from the vascular cambium to the medulla. The methodology followed that traditionally recommended for plant anatomy studies. Analyses of the material as well were as the measurements and images were performed by using a light microscopic (Olympus - BX41). In radial section, tracheid length showed a well-defined increase in length from medulla to cambium, which was statistically significant based on the student "t" test. There was minimal variation in tracheid diameter and no variation in cell wall thickness. Results are discussed in relation to factors that may influence variation in tracheids along the tree stem.

Podocarpus lambertii, popularmente conhecida como pinheiro-bravo é uma Podocarpaceae típica da região Sul do Brasil, família que se distingue de outras coníferas por possuir uma estrutura de suporte para o óvulo denominada "epimatium". O presente estudo teve como objetivo investigar, por meio de parâmetros morfológicos e anatômicos, os efeitos da poluição por petróleo na estrutura das folhas de Podocarpus lambertii Klotzsch ex Endl. (Podocarpaceae), popularmente conhecida por pinheiro-bravo. As folhas foram coletadas no município de Araucária, Paraná, Brasil, na Refinaria de petróleo Presidente Getúlio Vargas (REPAR) um ano após exposição à poluição provocada pelo derramamento de petróleo. Esta espécie foi selecionada, porque além de ser nativa, apresentou um comportamento diferenciado dentre as demais diante da poluição. Folhas de nove indivíduos (seis expostos ao petróleo e três controle) foram coletadas. Foram avaliadas em microscopia fotônica as dimensões foliares (comprimento, largura e área foliar), a espessura dos tecidos e a densidade estomática. Os dados obtidos foram analisados estatisticamente. Nos indivíduos expostos à poluição, a superfície foliar foi menor, a densidade estomática e espessura dos tecidos foliares foram maiores quando comparados aos indivíduos controle. Os resultados obtidos permitem concluir que P. lambertti reagiu quando de sua exposição à poluição por petróleo.Podocarpus lambertii, locally known as "pinheiro-bravo", is a typical Podocarpaceae from Southern Brazil. This family is the most diverse of conifers; it has a distinguishing characteristic, namely the presence of an ovule support structure, called an epimatium. The aim of this study was to investigate the effect of oil pollution on the leaf structure of P. lambertii through morphology and anatomy. Leaves were collected in Araucária Municipality, Paraná, Brazil, at the Presidente Getúlio Vargas Petroleum Refinery one year after they had been exposed to pollution by an oil spill. This species was studied because besides being a native species, it behaved differently from the other species when faced with pollution. Nine individuals were selected (six exposed to pollution and three controls). We analyzed the leaf surface (length, width and leaf area), tissue thickness and stomatal density using light microscopy. The data were statistically analyzed. Leaf anatomy was rather variable. The individuals that were exposed to pollution had smaller leaf surfaces, while stomatal density and thickness of leaf tissues were greater when compared to the control.

* Background and Aims Conifers dominated wet lowland tropical forests 100 million years ago (MYA). With a few exceptions in the Podocarpaceae and Araucariaceae, conifers are now absent from this biome. This shift to angiosperm dominance also coincided with a large decline in atmospheric CO2 concentration (ca). We compared growth and physiological performance of two lowland tropical angiosperms and conifers at ca levels representing pre-industrial (280 ppm), ambient (400 ppm) and Eocene (800 ppm) conditions to explore how differences in ca affect the growth and water-use efficiency (WUE) of seedlings from these groups. Methods Two conifers (Araucaria heterophylla and Podocarpus guatemalensis) and two angiosperm trees (Tabebuia rosea and Chrysophyllum cainito) were grown in climate-controlled glasshouses in Panama. Growth, photosynthetic rates, nutrient uptake, and nutrient use and water-use efficiencies were measured. * Key Results Podocarpus seedlings showed a stronger (66%) increase in relative growth rate with increasing ca relative to Araucaria (19%) and the angiosperms (no growth enhancement). The response of Podocarpus is consistent with expectations for species with conservative growth traits and low mesophyll diffusion conductance. While previous work has shown limited stomatal response of conifers to ca, we found that the two conifers had significantly greater increases in leaf and whole-plant WUE than the angiosperms, reflecting increased photosynthetic rate and reduced stomatal conductance. Foliar nitrogen isotope ratios (d15 N) and soil nitrate concentrations indicated a preference in Podocarpus for ammonium over nitrate, which may impact nitrogen uptake relative to nitrate assimilators under high ca. * Significance Podocarps colonized tropical forests after angiosperms achieved dominance and are now restricted to infertile soils. Although limited to a single species, our data suggest that higher ca may have been favourable for podocarp colonization of tropical South America 60 MYA, while plasticity in photosynthetic capacity and WUE may help account for their continued persistence under large changes in ca since the Eocene. [ABSTRACT FROM AUTHOR]