bluuebunny/crossref_metadata_2025_split huggingface dataset:
First Report of New Phytoplasma Diseases Associated with Soybean, Sweet Pepper, and Passion Fruit in Costa Rica
Authors: Villalobos W. , Moreira L. , Rivera C. , Lee I.-M. 
Published: January 2009

A new soybean disease outbreak occurred in 2002 in a soybean (Glycine max) plantation in Alajuela Province, Costa Rica. Symptoms on the affected plants included general stunting, small leaves, formation of excessive buds, and aborted seed pods. In the same region, two other diseases, one in sweet pepper (Capsicum annuum) fields and another affecting passion fruit (Passiflora edulis) vines, were also found. Symptoms on sweet pepper plants included unusually dark green leaves, some of which exhibited a rugose symptom with a zigzag pattern to the midvein, and purple vein discoloration. Passion fruit vines exhibited bud proliferation. Collectively, symptoms resembled those commonly attributed to phytoplasmal infections. Total nucleic acid was extracted from veinal tissues of leaves or buds (soybean). A nested PCR assay using primer pair P1/P7 followed by R16F2n/R16R2 (1) was employed for the detection of putative phytoplasmas that might be associated within symptomatic plants. All seven symptomatic plants (three soybean, three sweet pepper, and one passion fruit) tested, but not healthy controls, yielded positive results. Restriction fragment length polymorphism (RFLP) analysis of nested PCR products using restriction enzymes AluI, BfaI, HhaI, MseI, and RsaI indicated that the three diseases were associated with a very similar or identical phytoplasma. RFLP patterns and sequence analysis of cloned 16S rDNAs (GenBank Accession Nos. FJ226068–FJ226073) revealed that the phytoplasma shared less than 97.5% sequence homology with all previously classified phytoplasmas, and, as such, represents a new taxon most closely related to 16SrXII group (1) strains. To our knowledge, this is the first report of a new phytoplasma associated with diseases of soybean, sweet pepper, and passion fruit in Costa Rica. Reference: (1) I.-M. Lee et al. Int. J. Syst. Bacteriol. 48:1153, 1998.
First Report of Soybean Pod and Stem Blight Caused by Diaporthe phaseolorum var. sojae in Taiwan
Authors: Chen C. H. , Wang T. C. , Seo M. J. 
Published: January 2009

Genera, Diaporthe and Phomopsis, from an important pathogenic complex of soybean (Glycine max) throughout the world, cause reductions in plant stands, yield, and seed health and quality (1). In a study of the Diaporthe/Phomopsis complex in Taiwan in March 2008, four stem samples with black fruiting structures in linear rows on senescent soybean were collected from the research fields at AVRDC, Shanhua, Tainan, Taiwan. Unidentified fungal isolates were obtained by surface disinfection of infected stems and plating excised tissues on potato dextrose agar (PDA). Colonies of the isolates showed ropelike white mycelia with yellowish tonalities. Small and scattered black stromata were observed frequently in the medium. Mutic pycnidia were found solitarily or aggregated in conidiomata on PDA plates after 10 days of incubation at 24°C with a 12-h photoperiod with near-UV light. All isolates produced α-conidia that measured 8.78 × 3.32 (7.00 to11.00 × 3.00 to 4.00) μm, and sporadically, β-conidia of 30.58 × 0.85 (26.00 to 33.00 × 0.60 to 1.20) μm. Perithecia were not observed in the collected stem samples or the fungal cultures on PDA. Restriction fragment length polymorphism patterns of the PCR products amplified by ITS4 and ITS5 primers for all isolates were identical to the patterns reported for Diaporthe phaseolorum var. sojae (3). Thus, all isolates were identified as D. phaseolorum var. sojae on the basis of morphologic and genetic characteristics (2,3). Pathogenicity was confirmed through inoculations during the V2 growth stage of soybean seedlings by atomizing conidial suspensions (1 × 107 α-conidia/ml) of each isolate on soybean seedlings as well as by injecting the inoculum into soybean stems separately. Four plants in each of three replications were inoculated for each method and six noninoculated plants served as controls. Plants were incubated in a growth chamber at 25°C and maintaining relative humidity at 100% by a humidifier for 48 h in darkness; thereafter, plants were maintained in the greenhouse at temperatures ranging from 23 to 34°C. Seven days after inoculation, red-brown leaf spots and coalescent lesions were observed on seedlings atomized by inoculum suspensions, as well as brown lesions and black pycnida in linear rows observed on plants inoculated by stem injection. No symptoms were observed on noninoculated plants. The fungal isolates obtained from inoculated soybeans were morphologically identical to those used as inoculum. The pathogenicity test was repeated twice. To our knowledge, this is the first explicit report identifying the causal agent of soybean pod and stem blight in Taiwan. The vouchers of infected specimens are available at AVRDC-The World Vegetable Center. Reference: (1) R. P. Mulrooney. Plant Dis. 70:600, 1988. (2) R. N. Pioli et al. Phytopathology 93:136, 2003. (3) A. W. Zhang et al. Phytopathology 88:1306, 1998.
First Report of Avocado sunblotch viroid in Avocado from Michoacán, México
Authors: De La Torre-A R. , Téliz-Ortiz D. , Pallás V. , Sánchez-Navarro J. A. 
Published: January 2009

The State of Michoacán, México cultivates approximately 100,000 ha of avocados (Persea americana M.) (4). During a survey from 2006 to 2007 in cv. Hass avocado groves in Tingambato County, in the State of Michoacán, deep yellow spots and streaks, which sometimes became necrotic or reddish, were observed on the skin of fruits and the pulp of the fruit also showed big yellow spots. Some young shoots developed fine, yellow streaks, and leaves of symptomatic trees sometimes showed irregular, white-to-yellow spots. These symptoms were similar to those recorded for Avocado sunblotch viroid (ASBVd) (3). To determine if ABSVd was associated with these symptoms, total RNA extracted (1) from the skin and pulp of symptomatic and asymptomatic fruits and also from leaves and bark of shoots from five trees collected in a commercial plot in Tingambato County was tested by a one-step reverse transcription (RT)-PCR protocol using one primer pair to amplify specifically the complete ASBVd genome sequence (3). All 30 samples of skin and pulp of fruits, leaves, and cortex of shoots from symptomatic trees yielded two PCR fragments with estimated sizes of 250 and 500 base pairs (bp) corresponding to the putative monomeric and dimeric forms of ASBVd, respectively. The 500-bp RT-PCR fragments obtained from the different samples were purified from an agarose gel and cloned. The 249-bp nucleotide sequence of the ASBVd genomic monomer was determined using the clones from the fruit skin from sample Arb No. 3 (GenBank Accession No. EU888588), pulp from sample Arb No. 5 (GenBank Accession No. EU888590), leaves from samples Arb No. 15 (GenBank Accession No. EU888589) and Arb No. 8 (GenBank Accession Nos. EU888591 and EU888592), and cortex of shoots from sample Arb No. 16 (GenBank Accession Nos. EU888593, EU888594, EU888595, EU888596, and EU888597). BLAST analysis of the ASBVd sequences showed a range of 98 to 100% nucleotide identity to ASBVd sequences (GenBank Accession Nos. AF404064, AF404051, or AF229821). A clone of the Michoacán ASBVd (GenBank Accession No. EU888593) was used to synthesize a Dig-High Prime-UTP-T7 (Roche, Mannheim, Germany) fluorescent riboprobe complementary to the ASBVd plus strand to perform a dot-blot analysis as described previously (2). All ASBVd samples positive by RT-PCR gave a strong signal in the dot-blot analysis. This riboprobe will be used to index the ASBVd in other commercial avocado groves in Michoacán. To our knowledge, this is the first report of ASBVd in Michoacán, México. References: (1) D. J. Mackenzie et al. Plant Dis. 81:222, 1997. (2) J. A. Sánchez-Navarro et al. Plant Pathol. 47:780, 1998. (3) R. J. Schnell et al. Plant Dis. 81:1023, 1997. (4) D. Téliz and A. Mora. El aguacate y su Manejo Integrado. Mundiprensa, Mexico City, 2007.
Individual experience and evolutionary history of predation affect expression of heritable variation in fish personality and morphology
Authors: Dingemanse Niels J , Van der Plas Fons , Wright Jonathan , Réale Denis , Schrama Maarten , Roff Derek A , Van der Zee Els , Barber Iain 
Published: January 2009

Predation plays a central role in evolutionary processes, but little is known about how predators affect the expression of heritable variation, restricting our ability to predict evolutionary effects of predation. We reared families of three-spined sticklebackGasterosteus aculeatusfrom two populations—one with a history of fish predation (predator sympatric) and one without (predator naive)—and experimentally manipulated experience of predators during ontogeny. For a suite of ecologically relevant behavioural (‘personality’) and morphological traits, we then estimated two key variance components, additive genetic variance (VA) and residual variance (VR), that jointly shape narrow-sense heritability (h2=VA/(VA+VR)). Both population and treatment differentially affectedVAversusVR, henceh2, but only for certain traits. The predator-naive population generally had lowerVAandh2values than the predator-sympatric population for personality behaviours, but not morphological traits. Values ofVRandh2were increased for some, but decreased for other personality traits in the predator-exposed treatment. For some personality traits,VAandh2values were affected by treatment in the predator-naive population, but not in the predator-sympatric population, implying that the latter harboured less genetic variation for behavioural plasticity.Replication and experimental manipulation of predation regime are now needed to confirm that these population differences were related to variation in predator-induced selection. Cross-environment genetic correlations (rA) were tight for most traits, suggesting that predator-induced selection can affect the evolution of the same trait expressed in the absence of predators. The treatment effects on variance components imply that predators can affect evolution, not only by acting directly as selective agents, but also by influencing the expression of heritable variation.
Constitutive Repression and Activation of Auxin Signaling in Arabidopsis
Authors: Li Hanbing , Cheng Yan , Murphy Angus , Hagen Gretchen , Guilfoyle Tom J. 
Published: January 2009

Abstract
Aux/IAA proteins are proposed to be transcriptional repressors that play a crucial role in auxin signaling by interacting with auxin response factors and repressing early/primary auxin response gene expression. In assays with transfected protoplasts, this repression was previously shown to occur when auxin concentrations in a cell are low, and derepression/activation was observed when auxin concentrations are elevated. Here we show that a stabilized version of the Arabidopsis (Arabidopsis thaliana) IAA17 repressor, when expressed constitutively or in a specific cell type in Arabidopsis plants, confers phenotypes similar to plants with decreased auxin levels. In contrast, a stabilized version of IAA17 that was converted to a transcriptional activator confers phenotypes similar to plants with increased auxin levels, when expressed under the same conditions in Arabidopsis plants. Free auxin levels were unchanged compared to control (DR5:β-glucuronidase), however, in the seedlings expressing the IAA17 repressor and activator. These results together with our previous results carried out in transfected protoplasts suggest that the hormone auxin can be bypassed to regulate auxin signaling in a cell-autonomous manner in plants.
Myc down‐regulation affects cyclin D1/cdk4 activity and induces apoptosis via Smac/Diablo pathway in an astrocytoma cell line
Authors: Amendola D.  , De Salvo M.  , Marchese R.  , Falzacappa C. Verga  , Stigliano A.  , Carico E.  , Brunetti E.  , Moscarini M.  , Bucci B.  
Published: January 2009

Abstract  Objectives:  We investigated the antiproliferative effect of Myc down‐regulation via cell proliferation inhibition, cell cycle perturbation and apoptosis in two human astrocytoma models (T98G and ADF) steadily expressing an inducible c‐myc Anti‐sense RNA.Materials and methods:  Cell growth experiments were performed using the trypan blue dye exclusion test and cell cycle analysis was evaluated by flow cytometry. Cell cycle molecules were detected by Western blot analysis, co‐immunoprecipitation and reverse transcription–polymerase chain reaction assays.Results:  We showed that Myc down‐regulation in astrocytoma cells led to G1 accumulation and an inhibition of cell proliferation characterized by S phase delay. Co‐immunoprecipitation experiments detected formation of inactive cyclin D1/cdk4 complexes as evaluated by presence of an active unphosphorylated form of retinoblastoma protein, the best characterized target substrate for cyclin D1/cdk4 complex, in ADF pINDc‐myc anti‐sense 7 cells. We also found that either p57Kip2 “apice” or p27Kip1 “apice” inhibitors bound to cyclin D1/cdk4 complex, thus, suggesting that they cooperated to inhibit the activity of cyclin D1/cdk4. Moreover, c‐Myc down‐regulation led to activation of the apoptotic mitochondrial pathway, characterized by release of cytochrome c and Smac/Diablo proteins and by reduction of c‐IAP levels through activation of proteasome‐mediated protein degradation system.Conclusions:  Our results suggest that c‐Myc could be considered as a good target for the study of new approaches in anticancer astrocytoma treatment.
Using an algorithmic model to reveal individually variable movement decisions in a wintering sea duck
Authors: Oppel Steffen , Powell Abby N. , Dickson D. Lynne 
Published: January 2009

SummaryMany migratory birds are assumed to remain fairly stationary during winter. However, recent research indicates that mid‐winter movements are evident in a variety of bird species, and the factors causing individuals to move are poorly understood.We examined the winter movements of 95 individual king eiders (Somateria spectabilis, L.) tracked with satellite transmitters in the Bering Sea between 2002 and 2006 to explore whether environmental factors such as day length, location, sea ice, and habitat quality could explain the occurrence of winter movements longer than 50 km.We used a novel algorithmic random forest model to assess the importance of variables predicting whether a bird remained or departed from a wintering site.We found extremely high individual variability in winter movement decisions by king eiders, and the individual bird was the most important variable followed by location, date, and sea ice concentration.We conclude that individual strategies exist that interact with environmental conditions to form multiple movement patterns.While a minor proportion of winter movements may be forced by environmental conditions, we propose that many winter movements may be of an exploratory nature where individuals aim to acquire information about alternative wintering sites that may enhance their survival probability at some point in time when environmental fluctuation renders their preferred wintering site unsuitable.
Panbiogeographical study of hagfishes: an anachronistic analysis
Authors: Briggs J. C. 
Published: January 2009

AbstractIn a recent paper by M. J. Cavalcanti and V. Gallo, ‘Panbiogeographical analysis of distribution patterns in hagfishes (Craniata: Myxinidae)’ (Journal of Biogeography, 2008, 35, 1258–1268), the authors studied the biogeography of an ancient fish family (Myxinidae) in the hope that the contemporary distributions of the species would reveal their past history and that of the ocean basins where they reside. In order to accomplish this task, there are several criteria that should have been met: (1) the ages of the taxa utilized (species) would have to be old enough to reflect the history of the areas where they are found, (2) the identification of the species as listed in the databases would have to be accurate, (3) the geographical locations indicated on the figures would have to be consistent with the statements in the text, and (4) the significance of the vicariant patterns would have to depend on evidence pertaining to the ages of such patterns. Unfortunately, it appears that none of these conditions has been met. It seems apparent that faith in an antiquated method of analysis led to neglect of the necessary steps in the analysis. This leaves little justification for publication of the paper, except to show that hagfishes are very widely distributed.
Structural equation modelling detects unexpected differences between bryophyte and vascular plant richness along multiple environmental gradients
Authors: Spitale Daniel , Petraglia Alessandro , Tomaselli Marcello 
Published: January 2009

AbstractAim  The aim of this study was to develop and evaluate a structural equation model explaining the species richness of bryophytes and vascular plants along multiple environmental gradients. Our primary interests in developing this model were: (1) to evaluate the effect of tree canopy along an altitudinal gradient on bryophyte and vascular plant richness; (2) to determine to what extent lithology was able to explain richness in the two groups of plants; (3) to assess whether anthropogenic disturbances decrease richness; and (4) to explore, comparing competing models, the causal links connecting spring area, discharge and spring complexity and to assess how these variables are related to richness.Location  Eighty‐six springs were sampled in the south‐eastern Alps of Italy, from the lowlands to high‐mountain regions, and on different lithologies.Methods  A structural equation model (SEM) was used to test certain hypotheses about the direct and indirect effects of altitude, canopy, lithology, disturbance, spring complexity, discharge and spring area on bryophyte and vascular plant richness. Competing models were evaluated and bootstrap simulation was used to determine the stability of parameter estimates.Results  SEM analysis made it possible to disentangle the different effects of canopy and lithology on bryophyte and vascular plant richness: for the former it was demonstrated that the increased richness with altitude was related primarily to lithology, whereas the latter increased because of the reduction of canopy cover. In addition, the model predicted that spring discharge determined the size of the spring area and even the complexity of the spring; these latter two variables influenced to different degrees both bryophyte and vascular plant richness. Anthropogenic disturbances affected the richness of bryophytes more than that of the vascular plants.Main conclusions  Our study demonstrates that several similarities in the patterns of bryophyte and vascular plant richness are in fact induced by different environmental variables.
The panbiogeograpy of hagfishes: a reply to Briggs’s anachronistic criticism
Authors: Cavalcanti Mauro J. 
Published: January 2009

Abstract Briggs’s (2009) criticisms of Cavalcanti & Gallo’s (2008) panbiogeographical study of hagfishes are shown to be either supportive of the criticized paper’s main findings or trivial, arising from an incomplete understanding of the panbiogeographical method and synthesis and of methodological prejudice against this conceptual framework.
Evaluation of pollination syndromes in Antillean Gesneriaceae: evidence for bat, hummingbird and generalized flowers
Authors: Martén‐Rodríguez Silvana , Almarales‐Castro Abel , Fenster Charles B. 
Published: January 2009

Summary

Current views about the predominance of generalization of pollination systems have stimulated controversy concerning the validity of pollination syndromes. In order to assess the extent to which floral characters reflect selection by the most important pollinators we evaluated pollination syndromes in a florally diverse plant group, the tribe Gesnerieae, a monophyletic plant radiation from the Antillean islands.
The study species include representatives of three groups of floral phenotypes, two of which chiefly correspond to ornithophilous and chiropterophilous syndromes. The third group includes subcampanulate flowers (characterized by a corolla constriction above the nectar chamber) with combinations of traits not fitting classic pollination syndromes.
Pollination systems were characterized for 19 Gesnerieae species in five Antillean islands between 2003 and 2007 and supplemented with observations of four Gesneriaceae species from Costa Rica. Pollinator visitation and frequency of contact with anthers or stigmas were used to calculate an index of pollinator importance. Eleven floral traits including morphology, phenology and rewards were used to assess clustering patterns in phenotype space.
Multidimensional scaling analysis of floral traits resulted in two clusters comprising: (i) tubular, red to yellow‐flowered species with diurnal anthesis, (ii) bell‐shaped‐flowered species; two groups of floral phenotypes were evident within the latter cluster, campanulate nocturnal and subcampanulate flowers. Correlations between pollinator importance values and floral axes revealed strong associations with the expected pollinators, hummingbirds for tubular flowers, and bats for campanulate flowers; subcampanulate‐flowered species had generalized pollination systems including bats, hummingbirds and insects. Discriminant analysis of the multivariate set of floral traits correctly classified 19 out of 23 species into the predicted pollination categories.
Synthesis. This study provides support for classic hummingbird and bat pollination syndromes, demonstrating the importance of pollinator‐mediated selection in the floral diversification of Antillean Gesnerieae. However, there was evidence for generalized pollination systems in species characterized by a unique morphological trait (corolla constriction), but with variable combinations of other floral traits. These findings suggests that floral phenotypes might also evolve under selection by various functional groups of pollinators, and underscores the importance of considering the presence and effectiveness of all floral visitors in pollination studies.