bluuebunny/crossref_metadata_2025 huggingface dataset:
APPLICATION OF POLAROGRAPHY AND CONTROLLED POTENTIAL ELECTROLYSIS IN PEPTIDE SYNTHESIS
Authors: Capobianco Giulio , Vidali Giorgio
Published: August 2010

Electrolysis of amino acids and peptides protected on the amino function has been conducted.

In aqueous medium the nitro group of w‐nitro arginine and o‐nitro sulfenyl are selectively removed by means of controlled potential electrolysis, whereas phthaloyl, tosyl, formyl, acetoacetyl, xanthyl, benzyloxycarbonyl, t‐butoxycarbonyl are stable under the electrolytic condition employed.
SYNTHESIS OF AN ACTINOMYCIN ANALOG WITH SUBSTITUTED LACTONE OXYGENS
Authors: Meienhofer Johannes , Patel Ravindra P.
Published: August 2010

A synthesis of a lactam analog of actinomycin D is described in which the threonine residues have been replaced by L‐α, β‐diaminopropionic acid. The key reaction, cyclization of the pentapeptide intermediate, was carried by a nitrophenyl ester condensation between the proline and sarcosine residues. [I′, I′‐Bis (L‐α, β‐diaminopropionic acid)]‐actinomycin D exhibited potent antibacterial activity.
Initiation of a screening protocol for polyoma virus results in a decreased rate of opportunistic non‐BK viral disease after renal transplantation
Authors: Koleilat I. , Kushnir L. , Gallichio M. , Conti D.J.
Published: August 2010

I. Koleilat, L. Kushnir, M. Gallichio, D.J. Conti. Initiation of a screening protocol for polyoma virus results in a decreased rate of opportunistic non‐BK viral disease after renal transplantation. Transpl Infect Dis 2011: 13: 1–8. All rights reserved

Background. Polyoma BK virus nephropathy (PVN) is a leading cause of renal allograft injury and loss. The mainstay of treatment, as there are no target therapies approved by the US Food & Drug Administration, is reduction in immunosuppression. However, current approaches are shifting to screening for viremia as an indicator of oncoming nephropathy, with subsequent reduction in immunotherapy. We attempted not only to replicate these data but also to evaluate the utility of polyoma viremia as a surrogate marker for overimmunosuppression in general, thus allowing prevention not only of PVN but also of other viral opportunistic infections such as cytomegalovirus (CMV) and Epstein–Barr virus (EBV) disease.

Patients and methods. We conducted a retrospective cohort analysis of renal transplant recipients at our center. The historical controls (2003–2005, n=134) had received their allograft before the institution of a monthly serum polymerase chain reaction (PCR) polyoma screening protocol. The screened cohort received their allograft afterwards (2006–2008, n=134). Screening was performed using PCR techniques with prompt reduction in immunosuppression for viremic patients. The patients were followed for the development of PVN, acute rejection, renal allograft function, and survival.

Results. Polyoma viremia was noted in 16% of the screened population, with none developing PVN after prompt reduction of immunosuppression. Clearance of the viremia occurred by 6 months in 95% of the patients after reduction of immunotherapy. No patient in the screened group developed CMV or EBV disease. Of the controls, 7 (5%) developed PVN and 12 (9%) developed CMV or EBV disease, compared with none of the screened patients (P<0.05). The incidence of acute rejection was comparable between the groups (4% controls, 5% screened). No deleterious effects were noted on patient or allograft survival, allograft function (measured by serum creatinine), rates of fungal infection, or the rate of post‐transplant lymphoproliferative disorder in the screened patients.

Conclusions. Monthly PCR monitoring for BK viremia, together with a modest decrease in immunotherapy, is not only safe but also effectively prevents PVN and is associated with a significantly decreased rate of CMV and EBV disease in renal transplant patients. BK viremia may also serve as a surrogate marker for overimmunosuppression.
Prediction of low haemoglobin levels in whole blood donors
Authors: Baart A. M. , de Kort W. L. A. M. , Moons K. G. M. , Vergouwe Y.
Published: August 2010

Background and Objectives  Each year, a relevant proportion of whole blood donors is deferred from donation because of low haemoglobin (Hb) levels. Such temporary deferrals are demoralizing, and donors may never return for a donation. Reliable predictions of Hb levels may guide the decision whether donors can be invited for the next donation. In this study, a prediction model was developed for the risk of low Hb levels.

Materials and Methods  Individual data from 5191 whole blood donors were analysed; 143 donors had a low Hb level. Eleven candidate predictors were considered in logistic regression models to predict low Hb levels. The performance of the prediction model was studied with the receiver operating characteristic (ROC) curve. Internal validity was assessed with a bootstrap procedure.

Results  Strong predictors were sex, seasonality, Hb level measured at the previous visit, difference in Hb levels between the previous two visits, time since the previous visit, deferral at the previous visit, and the total number of whole blood donations in the past 2 years. Internal validation showed an area under the ROC curve of 0·87.

Conclusion  The developed prediction model provides accurate discrimination between donors with low and appropriate Hb levels. The model predictions may be valuable to determine whether donors can be invited for a next donation, or whether some interventions such as postponement of the invitation are warranted. Potentially, this could decrease the number of donor deferrals for low Hb levels.
Egg Colour Covaries with Female Expression of a Male Ornament in the Spotless Starling (Sturnus unicolor)
Authors: López‐Rull Isabel , Celis Patricia , Gil Diego
Published: August 2010

The sexually selected egg colour hypothesis (SSECH) proposes that egg colouration is as a post‐mating sexually selected signal of female phenotypic quality, maintained by a higher allocation of paternal care. Similarly, some female traits can reflect genetic quality or condition and males could use this information in mate choice or in modulating parental investment. In our study, we examined the correlation of individual variation in egg colouration with female expression of a male ornament and how male feeding covaried with these two female traits in the spotless starling, in which egg colour varies widely between clutches and where both sexes possess showy throat feathers that are age dependent and that may signal individual quality. According to the SSECH, high‐quality females (females with longer throat feathers) are expected to lay more colourful eggs than low‐quality females and males should modify their feeding behaviour accordingly. By means of a principal component analysis, we found that most of the variation in egg colouration was due to brightness differences, and in a lower proportion to chromatic variation. Chromatic variation reflected a ultraviolet (UV) vs. greenness trade‐off and was positively associated with throat feather length: females with larger throat feathers laid eggs with higher UV and lower green reflectance. However, egg brightness was not related to female feather length, as the SSECH would predict. Male feedings were positively related to female throat feather length and negatively related to chromatic variation, meaning that males contributed more to nests of females with long throat feathers who laid eggs with higher UV and lower green reflectance. In conclusion, our data provide mixed support for the SSECH: although egg chromatic variation was related to female expression of a male ornament and male parental care, we found no evidence that egg brightness was involved in these processes.
Wing Colour Properties do not Reflect Male Condition in the American Rubyspot (Hetaerina americana)
Authors: Contreras‐Garduño Jorge , Buzatto Bruno A. , Abundis Lizeth , Nájera‐Cordero Karla , Córdoba‐Aguilar Alex
Published: August 2010

Adult males of the American rubyspot (Hetaerina americana) dispute riverine territories where females arrive to mate. On the wing basis, these males bear a red pigmentation spot whose area correlates with territorial disputes and mating rate: males with larger spots are more successful. This is explained by the fact that spot size correlates with fat muscular reserves which fuel flight during territorial intrusions. To further our understanding of sexual selection acting on the spot, here we have examined possible differences in three spot colour properties (red chroma, hue and brightness) in three distinct adult male ages [young, middle‐aged (when males are more likely to defend a territory) and old], social status (territorial and non‐territorial in middle‐aged males), and under two potentially, energetically and costly situations: when faced with an immune challenge [comparing a nylon‐implanted male group vs. a non‐implanted male group in two ages, teneral (previous to colour formation) and middle‐aged] and low diet levels (comparing a male set of middle‐aged animals that received food ad libitum vs. a male set that received no food). Our results indicate no change in colour properties across any of these comparisons. Taken together, these and previous results suggest that only spot size but not the spot characteristics we measured here, is sexually selected in males of this species at least in terms of pre‐copulatory male–male competition. That some of these colour properties have been related to male condition in other calopterygid damselflies cannot be generalized to the American rubyspot.
Sources of Selection on Signal Timing in a Tree Frog
Authors: Höbel Gerlinde , Gerhardt H. Carl
Published: August 2010

Signal‐timing adjustment is common in communally signaling species, and there is large variation in signal‐timing formats found in nature. We conducted a survey of geographic variation in female signal‐timing preferences and male signaling behavior of a tree frog to test predictions of two hypotheses about the sources of selection acting on signal‐timing behavior. We found that female preferences are important in shaping male signal timing, affecting the absolute placement of signals relative to the temporal limits of female preferences. Variation in other signal characters, particularly signal period, also affects signal timing, albeit in a more complicated pattern: the influence of signal period on signal timing varied between populations. Overall, our findings indicate that the evolution of male signal‐timing behavior is strongly influenced by female preferences and by an interaction with other aspects of male signaling behavior such as male signal period.
Does the Complexity of the Task Influence Manual Laterality in De Brazza’s Monkeys (Cercopithecus neglectus)?
Authors: Schweitzer Cécile , Bec Philippe , Blois‐Heulin Catherine
Published: August 2010

We assessed the manual preferences of 12 De Brazza’s monkeys (Cercopithecus neglectus) in spontaneous feeding situations and in two different coordinated bimanual tasks that were not visually guided. We recorded the hand used by each subject for 22 spontaneous activities, hand and digits use while extracting peanut butter from a hollow tube (tube task) and the hand used to extract candies from hanging plastic balls (ball task). Spontaneous activities revealed individual manual preferences but no population‐level biases. For both experimental tasks, all subjects were lateralized in their hand use. We found a left bias at the group level for the tube task, but no group‐level asymmetry for the ball task. Experimental tasks induced greater strength of laterality than did spontaneous activities. Although the size of our sample did not allow us to draw any conclusions concerning manual preference at the population level, this study stresses the importance of coordinated bimanual tasks to reveal manual laterality in non‐human primates.
An Experimental Analysis of Spatial Position Effects on Foraging and Vigilance in Brown‐Headed Cowbird flocks
Authors: Fernández‐Juricic Esteban , Beauchamp Guy
Published: August 2010

Several observational studies have found that the costs and benefits of social foraging vary as a function of spatial position in the group. However, it is difficult to make mechanistic inferences because several confounding factors, such as food deprivation levels, food availability, neighbor distance, and group size can mask or amplify spatial position effects. We attempted to address experimentally the effect of spatial position on foraging and vigilance in a group, controlling for many confounding factors. We used enclosures that restricted physical but not visual interactions between brown‐headed cowbirds and manipulated spatial position, flock size, and neighbor distance. Pecking rate (number of pecks per trial duration) was not related with position, but instantaneous pecking rate (number of pecks per foraging bout duration) was higher at the edge. The proportion of time spent head‐up (scanning and food‐handling) was also higher at the edge. For pecking rate and proportion of time spent scanning, changes in neighbor distance influenced the behavior of edge birds to a lesser extent than central birds. These results suggest that cowbirds at the edge perceived greater predation risk and that during the limited foraging time available, edge birds tried to compensate by foraging at a faster rate.
The Influence of Tail Autotomy on the Escape Response of the Cape Dwarf Gecko, Lygodactylus capensis
Authors: Medger Katarina , Verburgt Luke , Bateman Philip W.
Published: August 2010

Tail autotomy as a defence against predators occurs in many species of lizard. Although tail autotomy may provide an immediate benefit in terms of survival it may nevertheless be costly due to other functions of the tail. For example, tail autotomy may affect the locomotory performance of lizards during escape. We investigated the influence of tail autotomy on the escape performance of the Cape Dwarf Gecko, Lygodactylus capensis, on a vertical and a horizontal surface. Autotomized geckos were significantly slower than intact geckos during vertical escape, whereas tail autotomy did not influence the horizontal escape speed. Backward falling of the autotomized geckos on the vertical platform may explain the reduced speed. In addition, tail autotomy did not significantly affect body curvature and stride length of the geckos. The observed decrease of escape speed on a vertical platform may influence the habitat use and behaviour of these geckos. Ecological consequences resulting from tail autotomy are discussed in light of these findings.
Mate Guarding in the Androdioecious Clam Shrimp Eulimnadia texana: Male Assessment of Hermaphrodite Receptivity
Authors: Weeks Stephen C. , Benvenuto Chiara
Published: August 2010

Precopulatory mate guarding primarily occurs when males encounter receptive females at a low enough rate that such females become a valuable resource once encountered. Such circumstances are common in aquatic crustaceans wherein females are only receptive for a short period directly after molting. In these species, males commonly mate guard by physically attaching themselves to their prospective mates for hours to days at a time. To be effective in mate guarding, males must be able to assess the time to receptivity in their mates, which is commonly via chemical cues associated with molting. Clam shrimp in the genus Eulimnadia exhibit mate guarding, but with an important variation: these species are mixtures of males and hermaphrodites (androdioecy) rather than males and females. Nonetheless, the mate guarding behaviors of these shrimp are much the same as in other aquatic crustaceans. In this study, three projects were undertaken to determine the ability of Eulimnadia texana males to assess hermaphroditic receptivity. Males were found to be unable to assess receptivity without physically contacting hermaphrodites. However, after physical contact, males spent a significantly greater amount of time guarding receptive relative to non‐receptive hermaphrodites. Additionally, male interest in mate guarding was highest during the period between the dropping of one clutch of eggs and the extrusion of the following clutch. Because this period is also associated with hermaphroditic molting, it is consistent with the notion that males cue into chemicals associated with molting to determine hermaphroditic receptivity. These findings are consistent with previous studies of mating behavior in this species, and we discuss their importance to future tests of optimal mate guarding planned for these shrimp.
The Bold and the Variable: Fish with High Heterozygosity Act Recklessly in the Vicinity of Predators
Authors: Vilhunen Sampsa , Tiira Katriina , Laurila Anssi , Hirvonen Heikki
Published: August 2010

Variation in the innate behavioral response to predation threat is often assumed to reflect genetic differences among the prey individuals. To date, no published results, however, exist that would offer explanation for the origin of this behavioral variation within populations. Using microsatellites as markers, we estimated the genetic variability of juvenile brown trout (Salmo trutta) individuals whose behavior had been individually recorded in a trade‐off situation where both predator chemical cues and food were present. Mean overall heterozygosity and the internal relatedness of fish associated significantly with their activity and foraging, so that the genetically more variable individuals showed more risk‐prone behavior under predation risk. No association between genetic variability and behavior was found in trials where predator odors were not present. These results were consistent over the three study populations of brown trout with different backgrounds, suggesting that the phenomenon is of general nature in this species. Of the possible mechanisms suggested to enable the existence of the positive association between neutral microsatellite variation and fitness‐related trait, the local effect hypothesis gained more support from our data than the general effect hypothesis.
Aerial Contests, Sexual Selection and Flight Morphology in Solitary Pompilid Wasps
Authors: Kemp Darrell J. , Alcock John
Published: August 2010

Aerial contest competition has proven to be a challenging phenomenon to interpret in many territorial insects. Because the duels often consist of elaborate and/or high speed ascending maneuvers, the hypothesis that they are settled due to asymmetries in flight performance is intuitively appealing. We evaluated this hypothesis by contrasting differences in known morphological determinants of flight performance between (1) residents vs. non‐residents of the territorial wasp, Hemipepsis ustulata and between (2) H. ustulata vs. a non‐territorial relative, Pepsis thisbe. In the first contrast, resident male H. ustulata were seen to be larger, and had a tendency for reduced wing loading, but they did not possess greater flight musculature or wing aspect ratios (i.e., more elongated wings) than their non‐resident counterparts. In the second contrast, male H. ustulata exhibited clearly greater flight musculature and greater sexual dimorphism in this parameter (males more muscular), and also exhibited a slight tendency for greater wing loading and smaller aspect ratios than males of the patrolling species P. thisbe. Interestingly, although size is linked with territorial success in H. ustulata, males of this species were not larger than male P. thisbe, nor did the former species exhibit greater sexual size dimorphism. These results do not support the hypothesis that the repeated ascending contests of H. ustulata require, and select for, a high acceleration design. However, the observed intraspecific patterns of flight musculature suggest that high acceleration is favored in males of the perching species, perhaps for the ability to intercept passing receptive females.
Is Territory Defence related to Plumage Ornaments in the King Penguin Aptenodytes patagonicus?
Authors: Viera Vanessa M. , Nolan Paul M. , Côté Steeve D. , Jouventin Pierre , Groscolas René
Published: August 2010

Colourful ornaments in monogamous birds may be directed at potential mates or other conspecifics to signal individual condition, reproductive status or fighting ability, especially in monogamous and territorial species. We investigated whether the size of the orange auricular patch may be an indicator of aggressiveness in the king penguin Aptenodytes patagonicus, a monogamous and territorial seabird. The relationship between auricular patch size and defence behaviour was explored relative to territory location (centre vs. periphery of the colony), period of reproduction (early vs. late), state of reproduction (incubation vs. brooding) and sex. The proportion of time spent in territorial defence and the rate of aggressive behaviours were positively correlated with auricular patch size, mainly because central birds were more aggressive than peripheral birds and also had larger patch sizes. The period of reproduction, state of reproduction and sex did not interact with patch size to affect aggressiveness. Our results suggest that the size of the auricular patch in king penguins may be a reliable signal allowing individuals to evaluate the quality of mates or competitors in terms of aggressiveness. Whether aggressiveness is directly linked to patch size or indirectly through body condition, however, remains to be determined. In any event, birds with larger patches seem to gain central territories in the colony, thereby increasing their reproductive success. Finally, our study adds to the growing evidence that the evolution of sexually monomorphic ornaments may stem from mutual sexual selection.
Scent‐marking and intrasexual competition in a cooperative carnivore with low reproductive skew
Authors: Müller Corsin A. , Manser Marta B.
Published: August 2010

Most mammals scent‐mark and a variety of hypotheses have been put forward to explain this behaviour. Differences in the main function of scent‐marking between species are likely to be related to differences in social systems. Here, we investigate the functions of scent‐marking in a cooperatively breeding carnivore. In the banded mongoose (Mungos mungo), individuals of both sexes commonly breed in their natal group and reproductive skew within groups is low. Using experimental scent‐mark presentations, we tested predictions of the intrasexual competition, self‐advertisement to potential mates and dominance assertion hypotheses. Both males and females responded more intensely to scent marks of same‐sexed than of opposite‐sexed individuals. Dominant individuals counter‐marked more than subordinate ones and males showed higher counter‐marking rates than females, but only marginally so. During oestrus, responses to scent marks were increased by both sexes. Our findings strongly indicate that scent‐marking in the banded mongoose primarily serves a purpose in intrasexual competition both between and within groups. Unlike in other social herpestids and some solitary rodents, we found little evidence for self‐advertisement. We suggest that the peculiar social system of the banded mongoose results in self‐advertisement losing importance in this species, shifting the main function of scent‐marking to intrasexual competition.
Hosts’ Responses to Parasitic Eggs: Which Cues Elicit Hosts’ Egg Discrimination?
Authors: Moskát Csaba , Székely Tamás , Cuthill Innes C. , Kisbenedek Tibor
Published: August 2010

Many hosts of the common cuckoo (Cuculus canorus) exhibit egg recognition, and reject parasitic eggs. How do hosts discriminate cuckoo eggs from their own? Hosts might be able to recognize their own eggs using the specific pigment pattern on the outer eggshell surface, which may serve as a cue for recognition. We tested if patterns of egg pigments (spottedness) contain this information by manipulating spot density of great reed warbler eggs (Acrocephalus arundinaceus). We also manipulated the colour of eggs when the original spot pattern remained the same. Spot density (approximately 15–75%) did not significantly affect rejection rate (8–20% rejection), but when spots fully covered the eggs, i.e. the eggshell was plain dark brown, rejection rate increased abruptly to 100%. A loglinear model revealed the significant influence of colour on rejection rates, although there was no interactive effect between spottedness and colour. Our results strongly support the differential use of egg markers in host’s egg discrimination, suggesting that spot density has limited importance compared to eggshell colour.
Song Variation in a Recently Founded Population of the Dark‐Eyed Junco (Junco hyemalis)
Authors: Newman Melissa M. , Yeh Pamela J. , Price Trevor D.
Published: August 2010

During natural colonization events, songs are expected to change as a result of both selection and drift‐like processes. We studied song variation within a small isolated population of dark‐eyed juncos, Junco hyemalis, which became established in an unusual environment on the University of California at San Diego (UCSD) campus in the early 1980’s, and compared this variation with the native range. At UCSD, the average repertoire size is 4.2 song types/male, which is similar to that in the native range. There is a low level of song‐type sharing across the population. Typically a male shares at least one song type with on average 40% of his neighbors, and song‐type sharing decreases rapidly with distance. Thus song‐type diversity is high, and in this respect appears similar to that in ancestral mountain populations. These results suggest a moderate to large number of males founded and/or subsequently immigrated into the UCSD population, but several selection mechanisms, if coupled with a high cultural mutation rate, may also favor high song‐type diversity. When combined with results from a previous study, songs are significantly shorter at UCSD than in the mountain population we studied. It appears that founder effects have not influenced the evolution of songs in this population. More generally, if song‐type diversity and other features of song result from various social and natural selection pressures, many of these pressures may have remained similar between the native and the recently established population.
The Use of Theory in Behavioural Research
Authors: Taborsky Michael
Published: August 2010

A survey of recent publications in behavioural biology suggests that research in this field often lacks a formal approach linking theory and empiricism, which implies that there is scope for improvement. Frequently, hypotheses guiding empirical work are merely based on plausibility arguments, which is not necessarily wrong and may be useful especially at the early stages of an investigation. Behavioural studies based on a theoretical framework usually test qualitative predictions from a general model either with data from natural situations or by experimental scrutiny. Rarely, a quantitative approach is used where a model is parameterized by existing data and therefore generates precise, testable predictions. In general, there is a lack of awareness that much more is to be learnt from a mismatch between predictions and data than from accordance. The latter is prone to cause the ‘pseudo‐proof fallacy’, which is widespread in behavioural ecology. Behavioural physiology, on the other hand, often suffers a lack of proper theoretical models. Much can be gained in both fields if empiricists and theoreticians collaborate more closely towards the ultimate aim – to unravel the mechanisms of behaviour at both, ultimate and proximate levels.
Effect of Enterobacter aerogenes on the Rhizosphere Microflora of Apple Trees*
Authors: Marchi A. , Utkhede R. S.
Published: August 2010

Fifty–seven fungi and 59 bacteria were isolated from soils collected from two apple orchards located in Kelowna and Summerland, British Columbia, Canada. Sixteen fungi and 35 bacteria, respectively, were significantly inhibited by the biological control agent Enterobacter aerogeness in a dual culture test. These results indicate that the antibiotic(s) produced by this organism has a wide spectrum of activity. This ability of E. aerogenes may protect apple trees from infection by other, soil microorganisms.
A Narrow Range of Wavelengths Active in Regulating Apothecial Development in Sclerotinia sclerotiorum
Authors: Thaning C. , Nilsson H.‐E.
Published: August 2010

Three Swedish and one Canadian isolate of Sclerotinia sclerotiorum were tested for apothecial formation in light of different wavelengths and for measuring light absorbance of macerated apothecia and apothecia filtrate in a spectrophotometer. The apothecial formation was recorded after keeping laboratory‐produced sclerotia under different light filters illuminated by True‐Lite fluorescent tubes. The experiments, performed at room temperature, demonstrated that normal apothecia developed only in light of wavelengths between 276 and 319 nm, and that macerated apothecia and apothecia filtrate absorbed light at the same wavelengths with a maximum absorbance at 310 nm. The stipes showed a clear positive phototropism in light that was not essential for apothecia development. indicating that there may be different photoreceptors for phototropism and photomorphogenesis. Negative phototropism of stipes occurred at certain wavelengths in yellow light.
Comparative Influence of Flavonoids on the Toxicity of Copper to Alternaria alternata
Authors: Park S. H. , Kwon O. S. , Choi C. W. , Kim C. ‐J.
Published: August 2010

Three flavonols, morin, rutin and quercetin, and a flavonone, naringenin, were in vitro tested for their influence on the toxicity of copper to Alternaria alternata. Copper sulphate (CuSO4) displayed dose‐dependent inhibition of fungal growth, resulting in a reduction in growth by one‐half at 0.07 mm. The addition of quercetin and morin conferred substantial protection against the inhibition of fungal growth by copper, whereas naringenin and rutin offered protection less effectively. Higher concentrations of copper could overcome the flavonoid effect, but the reduction of copper toxicity was more apparent in the presence of quercetin than morin. The metal chelating ability of quercetin was highly specific for copper among toxic metals such as Co, Ni, Zn, and Cd. The results show that the protection effect of the flavonoids against copper toxicity is highly dependent on the keto function and hydroxyl group substitution of the flavonoid skeleton.
Development of Erysiphe pisi (Powdery Mildew) on Normal and Albino Mutants of Pea (Pisum sativum L.)
Authors: Singh U. P. , Prithiviraj B. , Sarma B. K.
Published: August 2010

Early development of Erysiphe pisi (powdery mildew) was studied on normal peas (with chlorophyll), natural albino mutants (without chlorophyll) and on chimeric leaves of pea induced by ethyl methane sulphonate (EMS) under different light exposures. Different light regimes [continuous light; continuous darkness; short day (8 h light/16 h darkness); long day (16 h light/8 h darkness)] did not influence the early development of E. pisi on pea leaves. However, under continuous darkness a lower number of haustoria was observed in comparison with other treatments. Erysiphe pisi failed to develop on naturally developed complete albino leaves as well as on the albino parts of chimeric leaves induced by EMS treatment. A lesser number of appressoria and haustoria was observed on albino leaves. Results suggest that the presence of some nondiffusable chemical(s) in normal leaves of pea is essential for the establishment of successful biotrophy.
Characterization of a Strain ofTobacco Mosaic VirusfromPetunia
Authors: Alexandre M. A. V. , Soares R. M. , Rivas E. B. , Duarte L. M. L. , Chagas C. M. , Saunal H. , Van Regenmortel M. H. V. , Richtzehain L. J.
Published: August 2010

Petunia plants collected in São Paulo City, Brazil, showing yellow mosaic, were naturally infected by a virus of the genusTobamovirusidentified according to particle morphology and size, host range, physical properties and cytopathic effects. On the basis of serological properties, amino acid composition and nucleotide sequence of the coat protein gene, the virus isolate was identified as a new strain ofTobacco mosaic virus(TMV‐p). A conspicuous feature of this virus infection is the presence of virus‐like particles within the mitochondrial matrix. The data from phylogenetic analysis indicate that TMV‐p belongs to subgroup 1 of the genusTobamovirus.
Detection of Ralstonia solanacearum in Potato Tubers by Polymerase Chain Reaction
Authors: Pastrik K.‐H. , Maiss E.
Published: August 2010

A new polymerase chain reaction (PCR) assay was developed for the detection of Ralstonia solanacearum in potato tubers. The designed primers PS‐1/PS‐2 based on the sequence data of the 16S rRNA gene. Using the optimized PCR protocol, it was possible to detect R. solanacearum cells artificially added to concentrated potato extracts in the range of 1–10 colony‐forming units (CFU) per PCR reaction mixture (10–100 CFU/ml potato homogenate). No amplification products were obtained, when bacteria belonging to other species or genera were submitted to PCR under the same conditions. A total of 10 different DNA extraction methods were adapted for the isolation of R. solanacearum DNA from potato homogenates and were compared for their suitability as pre‐PCR procedures.
Potentiation of Phytoalexin Accumulation in Elicitor‐treated Epicotyls of Pea (Pisum sativum) by a Diacylglycerol Kinase Inhibitor
Authors: Toyoda K. , Kawahara T. , Ichinose Y. , Yamada T. , Shiraishi T.
Published: August 2010

When epicotyl tissues of pea were treated with a diacylglycerol (DAG) kinase inhibitor (R59022), enhanced induction of the phytoalexin accumulation occurred which was induced by fungal elicitor. The marked induction was associated with a sustained accumulation of phenylalanine ammonia‐lyase (PAL)‐mRNA and the consequent increase in PAL activity. These results suggest that inhibition of DAG breakdown leads to increased induction of phytoalexin accumulation and support the hypothesis that DAG kinase negatively regulates the signal transduction.
Immunolocalization of Tomato Mosaic Tobamovirus in Roots of Red Spruce Seedlings
Authors: Bachand G. D. , Castello J. D.
Published: August 2010

The objective of this study was to determine the location of tomato mosaic tobamovirus (ToMV) in red spruce (Picea rubens) seedling roots. Roots were collected from uninfected and infected spruce seedlings at biweekly intervals, fixed in formaldehyde‐glacial acetic acid‐50% ethanol (1 : 1 : 18), embedded in paraffin, sectioned, and tested by indirect immunofluorescence (IF). ToMV was detected by IF in infected, but not in uninfected red spruce roots. All seedlings that tested positive by IF had previously tested positive by enzyme‐linked immunosorbent assay. Fluorescence was observed most frequently 2 weeks after inoculation in cortical and epidermal cells, as well as in the lateral root primordia. The ToMV was not observed in vascular tissue, the root cap, or meristematic cells. Virus distribution was uneven, and occurred in localized, concatenated pockets, parallel to the axis of the apical meristem. In older seedlings, fluorescence was associated with irregular‐shaped vesicles in cortical cells.
Grouping of Binucleate Rhizoctonia Anastomosis Group D (AG‐D) Isolates into Subgroups I and II Based on Whole‐Cell Fatty Acid Compositions
Authors: Priyatmojo A. , Yamauchi R. , Kageyama K. , Hyakumachi M.
Published: August 2010

Whole‐cell fatty acid compositions of binucleate Rhizoctonia AG‐D (R. cerealis) isolates representing subgroups I [AG‐D (I)] and II [AG‐D (II)] obtained from various host plants were compared. Ten fatty acids including myristic (14 : 0), pentadecanoic (15 : 0), palmitic (16 : 0), palmitoleic (16 : 1 cis9), heptadecanoic (17 : 0), 9‐heptadecenoic (17 : 1 cis9), stearic (18 : 0), oleic (18 : 1 cis9), linoleic (18 : 2 cis9,12) and linolenic (18 : 3 cis9,12) were consistently present in all isolates of Rhizoctonia AG‐D. The major fatty acids found were palmitic, oleic and linoleic acids, comprising 88‐93% of the whole‐cell fatty acid content. The remaining fatty acids were present in smaller amounts ranging from 0.01 to 5.03% of the whole‐cell fatty acid content. Palmitic and oleic acids were present in approximately two and three times higher concentrations in isolates of AG‐D (I) than in isolates of AG‐D (II), respectively. On the other hand, linoleic acid was about two times lower in isolates of AG‐D (I) than in isolates of AG‐D (II). Principal component and cluster analyses of the percentage composition of fatty acids showed distinct separation between AG‐D (I) and AG‐D (II). The results indicated that fatty acid analysis is useful for differentiating AG‐D (I) and AG‐D (II) and supported previous differentiation of the two subgroups on the basis of cultural characteristics, pathogenicity and DNA analyses. In addition, a Rhizoctonia AG‐Q isolate from bentgrass and Rhizoctonia AG‐D isolates causing foot rot of wheat and stem rot of mat rush were grouped in AG‐D (I), based on the percentage composition of fatty acids.
Biological Control of the Grapevine Dieback Fungus Eutypa lata I: Screening of Bacterial Antagonists
Authors: Schmidt C. S. , Lorenz D. , Wolf G. A.
Published: August 2010

Antifungal bacterial strains were assayed for antagonistic activity towards the grapevine dieback fungus Eutypa lata in vitro and on grape wood. One hundred and twenty‐one of 188 isolates (64%) exhibited antagonistic activity towards E. lata in vitro (> 83% of the tested actinomycetes, Bacillus and Erwinia herbicola strains and 32% of the Pseudomonas strains). On autoclaved grape wood discs, liquid cultures from 24 of 76 selected bacterial strains (32%) caused at least 50% suppression of mycelial growth over a period of 2 weeks. Among these were two Bacillus subtilis, four E. herbicola, two Serratia plymuthica and 16 actinomycete isolates. One B. subtilis strain (B1α), two E. herbicola strains (JII/E2 and JII/E4) and one actinomycete (A123) showed the highest degree of antagonism (70‐100% control over a period of 4 weeks). In E. herbicola and the actinomycete A123 the cell‐free supernatant was the active fraction of the applied liquid culture (100% control); suspended cells showed no or limited effect. Conversely, in B. subtilis the cells were the decisive component (50‐70% control). Erwinia herbicola JII/E2 and B. subtilis B1α inhibited growth of six different E. lata isolates on wood significantly. The strong antagonistic effect of the four bacterial strains was confirmed by the measurement of fungal hydrolase activity (chitinase, protease, cellulase). Activities of fungal hydrolases were highly correlated with mycelial growth on wood (r > 0.88). In B. subtilis B1α antagonistic activity and ability to colonize grape wood was further demonstrated by cryo‐scanning electron microscopy.
Diffusion of Patulin in the Flesh of Pears Inoculated with Four Post‐harvest Pathogens
Authors: Laidou I. A. , Thanassoulopoulos C. C. , Liakopoulou‐Kyriakides M.
Published: August 2010

The fungi Penicillium expansum, Aspergillus flavus, Stemphylium vesicarium and Alternaria alternata were experimentally inoculated into pear fruits of cv. Abate fetel. The infected fruits were split longitudinally through the centre of lesions (5, 10, 15 and 20 mm in diameter) and were divided into four sections, from tissues below the lesions to tissues around the carpel area. The aforementioned fungi were isolated in different frequencies from all sections that included diseased and healthy tissues. Patulin was detected in the flesh of pears with lesions 10 mm in diameter when inoculated with P. expansum, S. vesicarium and A. alternata, but not with A. flavus. Mycotoxin concentrations surpassed the accepted maximum residue limit in all sections, even in apparently sound tissues. This is the first report of invasion of these fungi, as well as patulin diffusion into different depths of pear fruits.
Morphological and Physiological Differentiation among Vegetative Compatibility Groups of Verticillium dahliae in Relation to V. longisporum
Authors: Zeise K. , Tiedemann* A. von
Published: August 2010

Twenty‐four isolates of Verticillium dahliae from various geographic regions and host origins were assigned to vegetative compatibility groups (VCG) based on complementation between nitrate‐non‐utilizing (nit) mutants. The VCG assignment was associated with clearly distinguishable morphological and physiological characteristics. Most isolates of VCG 2B produced deep black colonies, small conidia (3.62 × 0.02 μ m), and spherical microsclerotia. They exhibited polyphenol oxidase (PPO) activity, high sporulation rate in shake cultures, fluorescence on sanguinarine‐amended PDA (snPDA) and excretion of dark pigment on Czapek Dox agar. The isolates assigned to VCG 4B had significantly longer conidia (4.73 × 0.04 μ m), spherical microsclerotia and white, fluffy colonies due to enhanced production of aerial mycelium. They excreted only traces of dark pigment, exhibited PPO activity, did not fluoresce on snPDA and had limited ability to sporulate in shake cultures. Except for lacking PPO activity the only heterokaryon self‐incompatible isolate (HSI) was similar to VCG 4B. Ten isolates of Verticillium longisporum from cruciferous hosts did not produce nit mutants. They had clearly longer conidia (7.41 × 0.05 μ m), formed elongate microsclerotia, and only poorly sporulated in shake cultures. They did not excrete dark pigment, lacked PPO, and failed to fluoresce on snPDA. The results indicate a clear morphological and physiological differentiation not only between the two species V. longisporum and V. dahliae but also among the VCGs of V. dahliae.
Four Spanish Isolates of Pear Decline Phytoplasma are Related to Other European Phytoplasmas of the Apple Proliferation Group *
Authors: Martin R. , Carazo G. , Arribas C. , Colino I. , Santiago R. , Blas C. De
Published: August 2010

A portion of about 1000 bp within the 16S rDNA of four pear decline (PD) symptomatic trees (two from Badajoz and two from Sevilla) was amplified by nested polymerase chain reaction (PCR) and directly sequenced. A sequence similarity search against the EMBL and GenBank nucleotide databases showed that they were most similar to two previously sequenced isolates of pear decline phytoplasma of German and Italian origin. In a phylogenetic analysis they clustered in a separate branch within the apple proliferation group. The four Spanish PD sequences were fully homologous to previously published primers R16F2n, primer forward (Ahrens and Seemüller. Phytopathology 82:828‐832, 1992) and PD probe. However, primers fPD, fU5 and R16F2 showed some mismatches with these sequences.
Germination and Survival of Fusarium graminearum Macroconidia as Affected by Environmental Factors
Authors: Beyer M. , Röding S. , Ludewig A. , Verreet J.‐A.
Published: August 2010

The effects of temperature (4–20°C), relative humidity (RH, 0–100%), pH (3–7), availability of nutrients (0–5 g/l sucrose) and artificial light (0–494 μmol/m2/s) on macroconidial germination of Fusarium graminearum were studied. Germ tubes emerged between 2 and 6 h after inoculation at 100% RH and 20°C. Incubation in light (205 ± 14 μmol/m/s) retarded the germination for approximately 0.5 h in comparison with incubation in darkness. The times required for 50% of the macroconidia to germinate were 3.5 h at 20°C, 5.4 h at 14°C and 26.3 h at 4°C. No germination was observed after an incubation period of 18 h at 20°C in darkness at RH less than 80%. At RH greater than 80%, germination increased with humidity. Germination was observed when macroconidia were incubated in glucose (5 g/l) or sucrose (concentration range from 2.5 × 10−4 to 5 g/l) whereas no germination was observed when macroconidia were incubated in sterile deionized water up to 22 h. Macroconidia germinated quantitatively within 18 h at pH 3–7. Repeated freezing (−15°C) and thawing (20°C) water agar plates with either germinated or non‐germinated macroconidia for up to five times did not prevent fungal growth after thawing. However, the fungal growth rate of mycelium was negatively related to the number of freezing events the non‐germinated macroconidia experienced. The fungal growth rate of mycelium was not significantly affected by the number of freezing events the germinated spores experienced. Incubation of macroconidia at low humidity (0–53% RH) suppressed germination and decreased the viability of the spores.
Biological Control of Black Rot (Xanthomonas campestris pv. campestris) of Cabbage in Tanzania with Bacillus strains
Authors: Massomo S. M. S. , Mortensen C. N. , Mabagala R. B. , Newman M.‐A. , Hockenhull J.
Published: August 2010

We evaluated the biocontrol efficacy of strains of Bacillus from Tanzania against the black rot pathogen, Xanthomonas campestris pv. campestris, in cabbage and the influence of the method of application under field conditions. The incidence and severity of black rot in the foliage, stems and heads of the highly susceptible cultivar, Copenhagen Market, were significantly reduced, especially when antagonists were applied through the roots as compared to application through the seeds or foliage (cotyledons). Promising antagonists included strains of B. cereus, B. lentimorbus and B. pumilus.
Genetic Variation Among Rhynchosporium secalis Populations of West Asia and North Africa as Revealed by RAPD and AFLP Analysis
Authors: Von Korff M. , Udupa S. M. , Yahyaoui A. , Baum M.
Published: August 2010

In order to study genetic variation among populations of Rhynchosporium secalis, 65 isolates were sampled from the West Asian and North African regions and used for polymerase chain reaction (PCR)‐based DNA marker analyses [namely random amplified polymorphism DNAs (RAPDs) and amplified fragment length polymorphisms (AFLPs)]. The study revealed that genetic diversity among and within populations accounted for 80 and 20%, respectively, of the total genetic diversity, indicating that the local field populations of R. secalis in West Asia and North Africa originated from genetically diverse source populations. Furthermore, high genetic similarity among isolates from the same location suggests that scald populations originated from a local founder population, possibly through rain‐splash‐dispersed conidia.
Detection of Aflatoxin in Aspergillus Species Isolated from Pistachio in Iran
Authors: Rahimi P. , Sharifnabi B. , Bahar M.
Published: August 2010

To estimate the incidence contamination of fresh pistachio nuts by aflatoxigenic fungi in Iran, nut samples were collected from pistachio orchards in Kerman, Rafsanjan and Isfahan regions. Out of the 200 Aspergillus isolates obtained, 11 species were identified as A. alliaceous, A. candidus, A. flavus, A. niger, A. niveus, A. ochraceus, A. parasiticus, A. tamari, A. terreus, A. unguis and A. wentii. For detection of aflatoxin production ability of the isolates, three target genes, namely aflR, aflJ, and omtB, used in PCR amplification. In all the examined cases, the degenerate primer designed for amplification of omtB gene, named omtBII, was able to amplify an expected 611 bp fragment in aflatoxigenic isolates in this study and yielded the same result as those obtained from TLC analysis and fluorescence ability by application of methylated β‐cyclodextrin in culture media. Using this procedure the significant incidence of aflatoxin‐producing aspergilli was confirmed in pistachio nuts produced in different regions of Iran. The results indicated that PCR method described here, in combination with fluorescence assay, is a reliable and simple confirmatory test for monitoring pistachio nuts contaminated with aflatoxinogenic aspergilli.