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1. Introduced mangroves escape damage from marine and terrestrial enemies

   https://doi.org/10.1002/ecy.3604  

   Davidson, Timothy M. ; Smith, Celia M. ; Torchin, Mark E. ( January 2022 , Ecology)

   The enemy release hypothesis (ERH) posits that introduced species often leave their enemies behind when introduced to a new range. This release from enemies may allow introduced species to achieve higher growth and reproduction and may explain why some invaders flourish in new locations. Red mangroves (Rhizophora mangle) were introduced to Hawaiʻi from Florida over a century ago. Because Hawaiʻi has no native mangroves, the arrival ofR. manglefundamentally changed the structure and function of estuarine shorelines. While numerous enemies affect red mangroves in their native range (tropical America), in Hawaiʻi, mangroves apparently experience little herbivory, which may explain why introduced mangroves are so productive, fecund, and continue to spread. In this study, we compared the effects of enemies in native and introduced populations of brackish red mangroves (R. mangle) in 8–10 sites in the native range (Florida, Belize, and Panama) and introduced range of mangroves (Hawaiʻi). At each site, we measured the (1) occurrence of enemies using timed visual surveys, (2) occurrence of damage to different mangrove structures (leaves, apical buds, dead twigs, roots, propagules, and seedlings), and (3) rate of propagule herbivory using tethering experiments. Consistent with the ERH, we found an order of magnitude less damage and fewer enemies in introduced than native mangrove sites. While introduced mangroves harbored few enemies and minimal damage, native mangroves were affected by numerous enemies, including leaf‐eating crabs, specialist bud moths, wood‐boring insects and isopods, and propagule predators. These patterns were consistent across all plant structures (roots to leaves), among marine and terrestrial enemies, and across functional groups (browsers, borers, pathogens, etc.), which demonstrates enemy escape occurs consistently among different functional groups and via trophic (e.g., herbivores) and non‐trophic (e.g., root borers) interactions. Our study is among the first biogeographical enemy release studies to take a comprehensive approach to quantifying the occurrence of damage from a broad suite of marine and terrestrial taxa across an array of wetland plant structures. Understanding how natural enemies alter this key foundation species will become increasingly relevant globally as mangroves continue to invade new regions through intentional plantings or range expansion driven by climate change.

    

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2. Exceptionally well-preserved Early Cretaceous leaves of Nilssoniopteris from central Mongolia

   https://doi.org/10.2478/acpa-2018-0016  

   Herrera, Fabiany ; Shi, Gongle ; Tsolmon, Gombosuren ; Ichinnorov, Niiden ; Takahashi, Masamichi ; Crane, Peter R. ; Herendeen, Patrick S. ( December 2018 , Acta Palaeobotanica)

   Abstract Two new Early Cretaceous (Aptian-Albian) species of fossil bennettitalean leaves are described from central Mongolia and assigned to the genus Nilssoniopteris . Nilssoniopteris tomentosa F.Herrera, G.Shi, Tsolmon, Ichinnorov, Takahashi, P.R.Crane, et Herend. sp. nov., isolated from bulk sediment samples collected for mesofossils in the Tevshiingovi Formation at the Tevshiin Govi opencast coal mine, is distinctive in having a dense, well-developed indumentum composed of branched, flattened multicellular trichomes on the abaxial leaf surface. This species provides the first direct evidence of complex multicellular trichomes in Bennettitales and adds to the evidence of leaf anatomical features in the group that were probably advantageous in increasing water use efficiency and/or perhaps had other functions such as deterring insect herbivory. Comparison with other well-preserved leaves of Bennettitales, including Nilssoniopteris shiveeovoensis F.Herrera, G.Shi, Tsolmon, Ichinnorov, Takahashi, P.R.Crane, et Herend. sp. nov., collected as hand specimens from the Khukhteeg Formation at the Shivee Ovoo locality, suggests that the trichome bases seen commonly on the abaxial cuticle of bennettitalean leaves bore trichomes with very low fossilization potential. In some cases these trichomes may have been shed as the leaves matured, but in other cases they probably decayed during diagenesis or were destroyed during the standard processes by which fossil leaf cuticles are prepared. 

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3. Differential alternative polyadenylation contributes to the developmental divergence between two rice subspecies, japonica and indica

   https://doi.org/10.1111/tpj.14209  

   Zhou, Qian ; Fu, Haihui ; Yang, Dewei ; Ye, Congting ; Zhu, Sheng ; Lin, Juncheng ; Ye, Wenbin ; Ji, Guoli ; Ye, Xinfu ; Wu, Xiaohui ; et al ( February 2019 , The Plant Journal)

   Alternative polyadenylation (APA) is a widespread post‐transcriptional mechanism that regulates gene expression throughmRNAmetabolism, playing a pivotal role in modulating phenotypic traits in rice (Oryza sativaL.). However, little is known about theAPA‐mediated regulation underlying the distinct characteristics between two major rice subspecies,indicaandjaponica. Using a poly(A)‐tag sequencing approach, polyadenylation (poly(A)) site profiles were investigated and compared pairwise from germination to the mature stage betweenindicaandjaponica, and extensive differentiation inAPAprofiles was detected genome‐wide. Genes with subspecies‐specific poly(A) sites were found to contribute to subspecies characteristics, particularly in disease resistance ofindicaand cold‐stress tolerance ofjaponica. In most tissues, differential usage ofAPAsites exhibited an apparent impact on the gene expression profiles between subspecies, and genes with those APA sites were significantly enriched in quantitative trait loci (QTL) related to yield traits, such as spikelet number and 1000‐seed weight. In leaves of the booting stage,APAsite‐switching genes displayed global shortening of 3′ untranslated regions with increased expression inindicacompared withjaponica, and they were overrepresented in the porphyrin and chlorophyll metabolism pathways. This phenomenon may lead to a higher chlorophyll content and photosynthesis inindicathan injaponica, being associated with their differential growth rates and yield potentials. We further constructed an online resource for querying and visualizing the poly(A) atlas in these two rice subspecies. Our results suggest thatAPAmay be largely involved in developmental differentiations between two rice subspecies, especially in leaf characteristics and the stress response, broadening our knowledge of the post‐transcriptional genetic basis underlying the divergence of rice traits.

    

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4. Two new species of Phaeohelotium ( Leotiomycetes : Helotiaceae ) from Chile and their putative ectomycorrhizal status

   https://doi.org/10.3114/fuse.2022.10.10  

   Grupe, A.C. ; Smith, M.E. ; Weier, A. ; Healy, R. ; Caiafa, M.V. ; Pfister, D.H. ; Haelewaters, D. ; Quandt, C.A. ( December 2022 , Fungal Systematics and Evolution)

   Species of the genus Phaeohelotium ( Leotiomycetes : Helotiaceae ) are cup fungi that grow on decaying wood, leaves, litter, and directly on soil. Northern Hemisphere species are primarily found on litter and wood, whereas in the Southern Hemisphere the genus includes a mix of saprotrophs as well as taxa that grow on soil in association with ectomycorrhizal trees. The diversity of this genus has not been fully explored in southern South America. Here we describe two species from Chile, Phaeohelotium maiusaurantium sp. nov . and Ph. pallidum sp. nov ., found on soil in Patagonian Nothofagaceae -dominated forests. We present macro- and micromorphological descriptions, illustrations, and molecular phylogenetic analyses. The two new species are placed in Phaeohelotium with high support in our 15-locus phylogeny as well as phylogenetic reconstructions based on the internal transcribed spacer (ITS) region of the nuclear ribosomal RNA gene. Our ITS phylogeny places both Ph. maiusaurantium and Ph. pallidum in a well-supported subclade that includes ectomycorrhizal root tip samples from Australasia. Similar species can be separated from these new taxa based on morphological characteristics, biogeography, substrate, and sequence data. In addition, two unnamed species from Chilean Nothofagaceae forests ( Phaeohelotium sp. 1 and Phaeohelotium sp. 2) are documented from scant collections and sequence data and await description until more material becomes available. 

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5. Late Cretaceous angiosperm woods from the McRae Formation, south-central New Mexico, USA: Part 2

   https://doi.org/DOI: 10.1086/695503  

   Estrada-Ruiz, E. ; Wheeler, E.A. ; Upchurch, G.R. ; Mack, G.H. ( January 2018 , International Journal of Plant Sciences)

   Premise of research. Over the past 3 decades, angiosperm woods have been reported from the Campanian to the Maastrichtian of southern Laramidia, including Coahuila and Chihuahua, Mexico; Big Bend National Park, Texas; and the San Juan Basin, New Mexico. Recent investigations of the upper Campanian (76.5 to >72.5 Ma) Jose Creek Member of the McRae Formation, south-central New Mexico, indicate an abundance of well-preserved silicified woods, representing one of the most diverse Cretaceous wood floras in the world. In this report, we describe four new angiosperm wood types. Methodology. The fossil woods described here were collected from the upper Campanian of south-central New Mexico, along the northeastern flank of the Caballo Mountains and in the adjacent Cutter Sag, and were studied using thin sections. The potential affinities of these McRae woods were determined by comparison with fossil and extant woods. Pivotal results. The woods reported here comprise one magnoliid and three eudicots with varying levels of comparability to extant taxa. Laurinoxylon rennerae sp. nov. belongs to Lauraceae and has a combination of features found in multiple extant genera variously referred to as Cinnamomeae Nees, Laureae Maout & Decaisne, or Lauroideae Burnett/core Lauraceae. Turneroxylon newmexicoense gen. et sp. nov. is a eudicot with many similarities to Dilleniaceae but differs in having narrower rays. Mcraeoxylon waddellii gen. et sp. nov. has a suite of features seen in several families of Malpighiales, Myrtales, and Oxalidales. McRae angiosperm wood type 1 has a suite of features found in genera of Dilleniales, Ericales, and Malpighiales. Conclusions. All wood types, with the exception of M. waddellii, have minimum axis diameters of 110 cm (12–50 cm), indicating that they represent trees. This reinforces previous evidence for the presence of small to large angiosperm trees in the Jose Creek Member and underscores the importance of woody angiosperms in vegetation of the southern Western Interior during the Campanian-Maastrichtian. 

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