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2022 ◽  
Author(s):  
Flávio Henrique Silveira Rabêlo ◽  
Felipe dos Santos ◽  
José Lavres ◽  
Luís Alleoni

Abstract Although several grasses have been evaluated for cadmium (Cd) phytoextraction, there are no studies assessing how Cd is accumulated and distributed in the tissues of Panicum maximum grown in mildly polluted soils. The evaluation of tillering, nutritional status and biomass yield of this grass, mainly along successive shoot regrowths, is not well studied so far. Thus, P. maximum Jacq. cv. Massai was grown for two periods in an Oxisol presenting bioavailable Cd concentrations varying from 0.04 (control) to 10.91 mg kg−1 soil. Biomass yield of leaves and stems´ growth have decreased under the highest Cd exposure, but it did not occur in the regrowth period, indicating that Cd-induced toxicity is stronger in the early stages of development of P. maximum. The tillering was not compromised even the basal node presenting Cd concentrations higher than 100 mg kg−1 DW. We identified a restriction on Cd transport upwards from basal node, which was the main local of Cd accumulation. Apparently, P, K, Mg, S and Cu are involved in processes that restrict Cd translocation and confer high tolerance to Cd in P. maximum. The Cd-induced nutritional disorders did not negatively correlate with factors used to calculate phytoextraction efficiency. However, the nutritional adjustments of P. maximum to cope with Cd stress restricted the upward Cd transport, which decreased the phytoextraction efficiency from the available Cd concentration of 5.93 mg kg−1 soil.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sebastian Kirchhof ◽  
Mariana L. Lyra ◽  
Ariel Rodríguez ◽  
Ivan Ineich ◽  
Johannes Müller ◽  
...  

AbstractClimate has a large impact on diversity and evolution of the world’s biota. The Eocene–Oligocene transition from tropical climate to cooler, drier environments was accompanied by global species turnover. A large number of Old World lacertid lizard lineages have diversified after the Eocene–Oligocene boundary. One of the most speciose reptile genera in the arid Palearctic, Acanthodactylus, contains two sub-Saharan species with unresolved phylogenetic relationship and unknown climatic preferences. We here aim to understand how and when adaptation to arid conditions occurred in Acanthodactylus and when tropical habitats where entered. Using whole mitogenomes from fresh and archival DNA and published sequences we recovered a well-supported Acanthodactylus phylogeny and underpinned the timing of diversification with environmental niche analyses of the sub-Saharan species A. guineensis and A. boueti in comparison to all arid Acanthodactylus. We found that A. guineensis represents an old lineage that splits from a basal node in the Western clade, and A. boueti is a derived lineage and probably not its sister. Their long branches characterize them—and especially A. guineensis—as lineages that may have persisted for a long time without further diversification or have undergone multiple extinctions. Environmental niche models verified the occurrence of A. guineensis and A. boueti in hot humid environments different from the other 42 arid Acanthodactylus species. While A. guineensis probably remained in tropical habitat from periods prior to the Eocene–Oligocene boundary, A. boueti entered tropical environments independently at a later period. Our results provide an important baseline for studying adaptation and the transition from humid to arid environments in Lacertidae.


Lankesteriana ◽  
2020 ◽  
Author(s):  
Jaap J. Vermeulen ◽  
André Schuiteman ◽  
Edward F. De Vogel

Sixteen new species of Bulbophyllum section Polymeres (Orchidaceae) from New Guinea (Papua New Guinea and Papua Province of Indonesia) are described. Four informal series in this speciose section are distinguished as an aid to identification and a key for these is provided. The sixteen species belong to two series, sharing one character: new shoots arise from a node along the rhizome or from the basal node of the pseudobulb, without being fused to it any further than the node from which they arise. The first group (with ten new species: Bulbophyllum cerastes, B. dologlossum, B. ischyron, B. nannae, B. orthoraphe, B. schistopogon, B. stagmatoglossum, B. subium, B. teinodragma, B. trivenosum) comprises plants with creeping rhizomes, the second (with six new species: Bulbophyllum farciminiferum, B. gymnothema, B. lipochilum, B. nudicaule, B. radula, B. squamiplectum) comprises plants with patent rhizomes. Key Words: Bulbophyllum section Polymeres informal series, new species, Papua New Guinea


2019 ◽  
Vol 21 (1) ◽  
Author(s):  
Qing Liu ◽  
Yi Su ◽  
Yunhua Zhu ◽  
Keqin Peng ◽  
Bin Hong ◽  
...  

Abstract Background Rice (Oryza sativa L.) feeds more than half of the world’s population. Ratooning rice is an economical alternative to the second seasonal rice, thus increasing the yield of ratooning rice is highly important. Results Here we report an applicable transgenic line constructed through the manipulation of osa-MIR156f expression in rice shoot using the OsGA3ox2 (D18) promoter. In seasonal rice, the D18–11 transgenic line showed moderate height and more effective tillers with normal panicle. In ratooning rice, axillary buds outgrew from the basal node of the D18–11 transgenic line before the harvest of seasonal rice. More effective tillers produced by the outgrowth of axillary buds contributed to the plant architecture improvement and yield increase. Additionally, it was found that osa-miR156f down-regulated the expression of tillering regulators, such as TEOSINTE BRANCHED1 (TB1) and LAX PANICLE 1 (LAX1). The expression of DWARF10, DWARF27 and DWARF53, three genes being involved in the biosynthesis and signaling of strigolactone (SL), decreased in the stem of the D18–11 transgenic line. Conclusion Our results indicated that the manipulation of osa-MIR156f expression may have application significance in rice genetic breeding. This study developed a novel strategy to regulate plant architecture and grain yield potential both in the seasonal and ratooning rice.


Zoosymposia ◽  
2019 ◽  
Vol 14 (1) ◽  
pp. 193-203
Author(s):  
DANA WEAVER ◽  
JOSEPH C. SPAGNA ◽  
PATINA K. MENDEZ

Barcoding datasets can serve as a resource for species associations and delineations, but single-gene trees estimated by distance methods do not provide strong estimates of phylogeny. Using DNA data from the Barcode of Life Database (BOLD), we calculate a phylogenetic tree for Oligophlebodes (Trichoptera: Thremmatidae), a small genus of caddisfly endemic to the Western United States. Here we estimate a preliminary phylogeny for Oligophlebodes using Bayesian likelihood, and compare it to trees produced by distance and standard likelihood methods. Using the barcode region of the cytochrome oxidase 1 (COI) gene, we analyzed 44 individuals representing five species (and 2 unknowns) and a sister-genus outgroup (Neophylax) from locations ranging from Southern New Mexico northwest into British Columbia. Partitioned Bayesian likelihood analysis under the F81 (1st codon positions) and HKY80 + I + Γ (for both the 2nd and 3rd codon positions) model gave the consensus topology (Neophylax toshi, (O. sierra, (O. ruthae inc. spc. 1 & 2, O. sigma, (spc. 3 & 4, (O. ardis, O. minutus)))). Species identifications were supported by monophyly of most species-level taxa. However, confirmation of species identifications of unknowns was complicated by incomplete taxon sampling for spc. 1 & 2. Placement of spc. 3 & 4 may serve as support for taxonomic review of O. minutus. Compared with an existing published phylogeny of Oligophlebodes BOLD sequences constructed under RAxML, the Bayesian hypothesis had higher resolution at the basal node of Oligophlebodes. Because of their support values, both likelihood trees are recommended over the BOLD TaxonID tree (an unrooted neighbor joining tree using the Kimura 2-parameter model). The novel topology produced in the Bayesian tree supports further explorations by likelihood-based methods, including partitioned analyses, of our preliminary Oligophlebodes dataset that can be used as additional lines of evidence to support morphological work.


2019 ◽  
Vol 13 ◽  
pp. 04002
Author(s):  
Matteo Gatti ◽  
Tommaso Frioni ◽  
Alessandra Garavani ◽  
Arianna Biagioni ◽  
Stefano Poni

Climate change impacts viticulture with even stronger effects on sparkling wines. Innovative cultural practices represent effective short-term solutions. Among these, postponement of winter pruning later than budburst delayed both vegetative and reproductive cycles as well as technological maturity of several varieties from different wine regions. This research aims to assess the impact of delayed winter pruning on grapevine performance as a function of training system. The trial was carried out in a Pinot Noir vineyard sited at 385 m asl in Central Italy. Delayed winter pruning was performed when unpruned canes had shoots showing three unfolded leaves (BBCH 13) and compared to standard winter pruning within two separate experiments focused on: i) cane pruning, and ii) spur pruning. Grapevine phenology, vegetative growth, fruit ripening kinetics and productivity of selected vines were assessed over three years. Delayed winter pruning postponed budburst by 20 and 31 days in Guyot and spur pruned cordons, respectively; then, differences diminished over time showing a maximum delay of 17 days at bloom and 7–10 days at harvest. Despite a decrease in yield (ranging from −35 to −47% in cane and spur pruning, respectively), delayed winter pruning increased titratable acidity (40–89%) and reduced sugars (721%) as compared to control vines. Although effects of delayed pruning were stronger in spur pruned vines, delayed winter pruning was effective also on cane-pruned vines, therefore adapting to varieties marked by low basal-node fruitfulness


2016 ◽  
Vol 23 (2) ◽  
pp. 189-194
Author(s):  
Bachan Lal Bhellum ◽  
Bikarma Singh

A new herb species of Urticaceae, Laportea stolonifera B. L. Bhellum & B. Singh, is described and illustrated from a restricted habitat of subtropical forest of Northwest Himalaya, India. The new taxon is vegetatively similar to Laportea ovalifolia (Schumach. & Thonn.) Chew, an African endemic species and Laportea interrupta (L.) Chew but differs by phenotypic characters such as cordate leaves, unbranched inflorescence, stem hairs types, linear cystoliths with varying shapes, and presence of 2 to 3 stolons arising from basal node of stems. The similarity with the allied species is due to similar habitats occupancy, but isolated geographically from each other. Laportea stolonifera is assessed as Endangered, and the population data, ecological parameters and associated taxa are also presented. A key to the genus Laportea is prepared for India has been presented in the text.Bangladesh J. Plant Taxon. 23(2): 189-194, 2016 (December)


PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e1555 ◽  
Author(s):  
Neil Brocklehurst

Body size is an extremely important characteristic, impacting on a variety of ecological and life-history traits. It is therefore important to understand the factors which may affect its evolution, and diet has attracted much interest in this context. A recent study which examined the evolution of the earliest terrestrial herbivores in the Late Carboniferous and Early Permian concluded that in the four herbivorous clades examined there was a trend towards increased body size, and that this increase was more substantial than that observed in closely related carnivorous clades. However, this hypothesis was not based on quantitative examination, and phylogenetic comparative methods provide a more robust means of testing such hypotheses. Here, the evolution of body size within different dietary regimes is examined in Captorhinidae, the most diverse and longest lived of these earliest high fibre herbivores. Evolutionary models were fit to their phylogeny to test for variation in rate and mode of evolution between the carnivorous and herbivorous members of this clade, and an analysis of rate variation throughout the tree was carried out. Estimates of ancestral body sizes were calculated in order to compare the rates and direction of evolution of lineages with different dietary regimes. Support for the idea that the high fibre herbivores within captorhinids are being drawn to a higher adaptive peak in body size than the carnivorous members of this clade is weak. A shift in rates of body size evolution is identified, but this does not coincide with the evolution of high-fibre herbivory, instead occurring earlier in time and at a more basal node. Herbivorous lineages which show an increase in size are not found to evolve at a faster rate than those which show a decrease; in fact, it is those which experience a size decrease which evolve at higher rates. It is possible the shift in rates of evolution is related to the improved food processing ability of the more derived captorhinids rather than a shift in diet, but the evidence for this is circumstantial.


2016 ◽  
Vol 29 (2) ◽  
pp. 87 ◽  
Author(s):  
Todd G. B. McLay ◽  
Michael J. Bayly ◽  
Pauline Y. Ladiges

Lamont et al. (2016) concluded that the Australian sclerophyllous genus Hakea (Proteaceae) arose 18million years ago in the South West of Western Australia (SWA) and dispersed 18 times to eastern (EA) and central Australia (CA) only 12million years ago (mid-Miocene). Their explanation of the biogeographic history of Hakea was based on the following: accepting a fully resolved molecular phylogenetic tree, although ~40% of nodes had posterior probability values below 0.95; using all nodes including geographically paralogous nodes to determine ancestral area probabilities; and applying a strict clock to estimate clade divergence times. Our re-analyses of the same dataset using a relaxed clock model pushes the age of Hakea to 32.4 (21.8–43.7) million years ago relative to its nearest outgroups, and the age of the divergence of two major clades (A and B) to 24.7 (17.2–33.7) million years ago. Calibration based on a new finding of Late Cretaceous fossil Banksia pushes these dates to 48.0 (24.3–75.2) million years ago and 36.6 (18.5–55.4) million years ago respectively. We confirm that each of the two main clades includes lineages in SWA, CA and EA. At the basal node of Clade A, two eastern Australian species form the sister group to three SWA scrub–heath–Eremaean species. These two groups together are sister to a large, mostly unresolved clade of SWA, CA and EA taxa. Similarly, at the base of Clade B is a polytomy of lineages from the SWA, CA and EA, with no resolution of area relationships. There is no evidence of a centre of origin and diversification of the genus is older than the mid-Miocene, being at least Oligocene, and probably older, although calibration points for molecular dating are too far removed from the ingroup to provide any great confidence in the methodology. Consideration should be given to the possibility of vicariance of multiple, widespread ancestral lineages as an explanation for lineages now disjunct between EA and SWA.


2015 ◽  
Author(s):  
Neil Brocklehurst

Body size is an extremely important characteristic, impacting on a variety of ecological and life-history traits. It is therefore important to understand the factors which may affect its evolution, and diet has attracted much interest in this context. A recent study, examining the evolution of the earliest terrestrial herbivores in the Late Carboniferous and Early Permian, concluded that in the four herbivorous clades examined there was a trend towards increased body size, and that this increase was more substantial than that observed in closely related carnivorous clades. However, this hypothesis was not based on quantitative examination, and phylogenetic comparative methods provide a more robust means of testing such hypotheses. Here, the evolution of body size within different dietary regimes is examined in Captorhinidae, the most diverse and longest lived of these earliest high fibre herbivores. Evolutionary models were fit to their phylogeny to test for variation in rate and mode of evolution between the carnivorous and herbivorous members of this clade, and an analysis of rate variation throughout the tree was carried out. Estimates of ancestral body sizes were calculated in order to compare the rates and direction of evolution of lineages with different dietary regimes. Support for the idea that the high fibre herbivores within captorhinids are being drawn to a higher adaptive peak in body size than the carnivorous members of this clade is weak. A shift in rates of body size evolution is identified, but this does not coincide with the evolution of high-fibre herbivory, instead occurring earlier in time and at a more basal node. Herbivorous lineages which show an increase in size are not found to evolve at a faster rate than those which show a decrease; in fact it is those which experience a size decrease which evolve at significantly higher rates. The opposite is true of the carnivorous lineages, suggesting that in captorhinids it is the carnivores which show the greater trend towards increased body size. It is possible the shift in rates of evolution is related to the improved food processing ability of the more derived captorhinids rather than a shift in diet, but the evidence for this is circumstantial.


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