938 resultados para Lepidostrobus xinjiangensis sp. nov.


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Mortality of calves born to provisioned mothers is identified in the literature as an issue of concern in dolphin provisioning programs. Wild dolphin provisioning at Tangalooma, Moreton Island, Australia has been occurring since 1992. Each evening, up to eight dolphins are provided with fish in a regulated provisioning program. In this paper, calf survival at the Tangalooma provisioning program is reported and contrasted with that from wild populations and from a similar provisioning program at Monkey Mia, Western Australia. At Tangalooma, the calf survival rate is 100%, including both orphaned and first-born calves, both of which are expected to have relatively low survival rates. Possible explanations for the high calf survival rate are explored. These include site attributes such as isolated location and high water quality, aspects of foraging ecology likely to benefit calves of provisioned mothers, and the management regime used in the provisioning program (e.g., duration and timing of provisioning; quality of provisioned fish).

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Genetic variation among 29 isolates of Fusarium oxysporum f.sp. zingiberi (Foz) collected from diseased ginger rhizome in production regions throughout Queensland was analysed using DNA amplification fingerprinting (DAF). Eight isolates of other Fusarium species and/or formae speciales were included for comparative analysis. Within the Foz isolates, three haplotypes were identified based on 17 polymorphic bands generated with five primers. Two groups showed very little genetic variation (98.6% similarity), whereas the third single isolate was quite distinct in terms of its molecular profile (77.2% similarity). Genetic similarity among the Fusarium solani, F. oxysporum f.sp. lycopersici and F. oxysporum f.sp. cubense races 1, 3 and 4 isolates compared well with the published literature.

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Aecidium sp. (Pucciniaceae) on Marsdenia sp. is reported for the first time from Australia.

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Parthenium (Parthenium hysterophorus L.), a major weed causing economic, environmental, and human and animal health problems in Australia and several countries in Asia, Africa, and the Pacific, has been a target for biological control in Australia since the mid-1970s. Nine species of insects and two rust fungi have been introduced as biological control agents into Australia. These include Carmenta sp. nr ithacae, a root feeding agent from Mexico. The larvae of C. sp. nr ithacae bore through the stem-base into the root where they feed on the cortical tissue of the taproot. During 1998-2002, 2,816 larval-infested plants and 387 adults were released at 31 sites across Queensland, Australia. Evidence of field establishment was first observed in two of the release sites in central Queensland in 2004. Annual surveys at these sites and nonrelease sites during 2006-2011 showed wide variations in the incidence and abundance of C. sp. nr ithacae between years and sites. Surveys at three of the nine release sites in northern Queensland and 16 of the 22 release sites in central Queensland confirmed the field establishment of C. sp. nr ithacae in four release sites and four nonrelease sites, all in central Queensland. No field establishment was evident in the inland region or in northern Queensland. A CLIMEX model based on the native range distribution of C. sp. nr ithacae predicts that areas east of the dividing range along the coast are more suitable for field establishment than inland areas. Future efforts to redistribute this agent should be restricted to areas identified as climatically favorable by the CLIMEX model.

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Crop models for herbaceous ornamental species typically include functions for temperature and photoperiod responses, but very few incorporate vernalization, which is a requirement of many traditional crops. This study investigated the development of floriculture crop models, which describe temperature responses, plus photoperiod or vernalization requirements, using Australian native ephemerals Brunonia australis and Calandrinia sp. A novel approach involved the use of a field crop modelling tool, DEVEL2. This optimization program estimates the parameters of selected functions within the development rate models using an iterative process that minimizes sum of squares residual between estimated and observed days for the phenological event. Parameter profiling and jack-knifing are included in DEVEL2 to remove bias from parameter estimates and introduce rigour into the parameter selection process. Development rate of B. australis from planting to first visible floral bud (VFB) was predicted using a multiplicative approach with a curvilinear function to describe temperature responses and a broken linear function to explain photoperiod responses. A similar model was used to describe the development rate of Calandrinia sp., except the photoperiod function was replaced with an exponential vernalization function, which explained a facultative cold requirement and included a coefficient for determining the vernalization ceiling temperature. Temperature was the main environmental factor influencing development rate for VFB to anthesis of both species and was predicted using a linear model. The phenology models for B. australis and Calandrinia sp. described development rate from planting to VFB and from VFB to anthesis in response to temperature and photoperiod or vernalization and may assist modelling efforts of other herbaceous ornamental plants. In addition to crop management, the vernalization function could be used to identify plant communities most at risk from predicted increases in temperature due to global warming.

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A survey of the Australian barley powdery mildew (Blumeria graminis f. sp. hordei) population was conducted in 2010 and 2011. Three hundred and sixty-two isolates of the pathogen were collected from 18 locations across all six states of Australia. Thirty-two barley differentials were used and 11 genotypes were able to differentiate the population with virulence frequencies varying from 14.5 % to 96.6 %. Twenty-seven pathotypes were detected. Fifteen of them were found in both years and they represented 92.0 % of all isolates examined. No virulence was found on a further 16 major genes for resistance (Mla1, Mla3, Mla6, Mla7, Mla9, Mla10, Mla12, Mla13, Mla23, MlaN81, Mlh, MlLa, Mlp1, Ml(IM9), Ml(St) and mlo) indicating a relatively simple population and the ready availability of diverse sources of resistance. This paper reports the powdery mildew virulences present in Australia, provides intelligence for future resistance breeding and sets a basis for further virulence studies.

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Since 1992, wild dolphin provisioning has occurred on a nightly basis at Tangalooma, a resort located on Moreton Island, Australia. Each evening at dusk up to 12 bottlenose dolphins (Tursiops sp.) are provided with fish in a regulated provisioning program. Since July 1998, biologists managing the program have documented 23 occurrences of "gift giving," when several of the provisioned dolphins have offered wild-caught cephalopod or fin fish species to staff members. The characteristics of each of these events are presented, and we explore the relationships between these events and their temporal patterns, and the age and sex of the dolphins involved. We also consider the behavioral explanations for the "gift giving," including prey sharing, play, and teaching behaviors, which have previously been described for cetaceans and other higher mammals. Gift giving may occur either as a discreet behavior (that may be a sequel to one or more other behaviors such as play or food preparation), or as a part of other behaviors, such as play and/or food sharing. It is most likely a manifestation of the particular relationship between the provisioned dolphins and the human participants in the provisioning. Gift giving has become an established but infrequent part of the culture of the provisioned dolphins at Tangalooma. © ISAZ 2012 Printed in the UK.

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Calonectria ilicicola, Gliocladiopsis sp. and Ilyonectria liriodendri were isolated from diseased roots of young avocado trees. Pathogenicity studies with seedlings of three avocado cultivars, Velvick, Hass and Reed, demonstrated that Calonectria ilicicola is a severe root rot pathogen, reducing the biomass of healthy roots, and reducing plant height over time. Calonectria ilicicola was re-isolated from diseased roots. Ilyonectria liriodendri and Gliocladiopsis sp. were not pathogenic and plant height was increased after Gliocladiopsis sp. amendment compared to all other treatments in trials with cvs Velvick and Hass.

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Harknessiaceae is introduced as a new family in the ascomycete order Diaporthales to accommodate species of Harknessia with their Wuestneia-like teleomorphs. The family is distinguished by having pycnidial conidiomata with brown, furfuraceous margins, brown conidia with hyaline, tube-like basal appendages, longitudinal striations, and rhexolytic secession. Six species occurring on Eucalyptus are newly introduced, namely H. australiensis, H. ellipsoidea, H. pseudohawaiiensis, and H. ravenstreetina from Australia, H. kleinzeeina from South Africa, and H. viterboensis from Italy. Epitypes are designated for H. spermatoidea and H. weresubiae, both also occurring on Eucalyptus. Members of Harknessia are commonly associated with leaf spots, but also occur as saprobes and endophytes in leaves and twigs of various angiosperm hosts.

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Fusarium oxysporum f. sp. cubense (Foc), causal agent of fusarium wilt of banana, is among the most destructive pathogens of banana and plantain. The development of a molecular diagnostic capable of reliably distinguishing between the various races of the pathogen is of key importance to disease management. However, attempts to distinguish isolates using the standard molecular loci typically used for fungal phylogenetics have been complicated by a poor correlation between phylogeny and pathogenicity. Among the available alternative loci are several putative effector genes, known as SIX genes, which have been successfully used to differentiate the three races of F. oxysporum f. sp. lycopersici. In this study, an international collection of Foc isolates was screened for the presence of the putative effector SIX8. Using a PCR and sequencing approach, variation in Foc-SIX8 was identified which allowed race 4 to be differentiated from race 1 and 2 isolates, and tropical and subtropical race 4 isolates to be distinguished from one another.

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Fusarium wilt of strawberry, incited by Fusarium oxysporum f. sp. fragariae (Fof), is a major disease of the cultivated strawberry (Fragaria xananassa) worldwide. An increase in disease outbreaks of the pathogen in Western Australia and Queensland plus the search for alternative disease management strategies place emphasis on the development of resistant cultivars. In response, a partial incomplete diallel cross involving four parents was performed for use in glasshouse resistance screenings. The resulting progeny were evaluated for their susceptibility to Fof. Best-performing progeny and suitability of progenies as parents were determined using data from disease severity ratings and analyzed using a linear mixed model incorporating a pedigree to produce best linear unbiased predictions of breeding values. Variation in disease response, ranging from highly susceptible to resistant, indicates a quantitative effect. The estimate of the narrow-sense heritability was 0.49 +/- 0.04 (SE), suggesting the population should be responsive to phenotypic recurrent selection. Several progeny genotypes have predicted breeding values higher than any of the parents. Knowledge of Fof resistance derived from this study can help select best parents for future crosses for the development of new strawberry cultivars with Fof resistance.

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An examination of ex-type and authentic cultures of 34 species of Bipolaris and Curvularia by phylogenetic analysis of four loci (EF-1α, GAPDH, ITS and LSU) resulted in nine new combinations in Curvularia, as well as new synonymies for some species of Bipolaris and Curvularia. Lectotypes are designated for Bipolaris secalis and Curvularia richardiae, and an epitype is designated for Curvularia crustacea. A new monotypic genus, Johnalcornia, is introduced to accommodate Bipolaris aberrans, which clusters sister to the newly described Porocercospora. Johnalcornia differs morphologically from this taxon by producing distinctive conidia-like chlamydospores as well as comparatively thick-walled, geniculate conidiophores, with conidiogenous cells that have conspicuous scars. Johnalcornia further differs from related genera by forming the second conidial septum in the apical cell.

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Cultures originally identified as Drechslera australiensis, from seeds of Chloris gayana in Japan, were the basis for Tsuda and Ueyama's new combination, Bipolaris australiensis, and its associated sexual morph Pseudocochliobolus australiensis. By studying ex-type materials of both Drechslera australiensis, which was originally isolated from seeds of Oryza sativa in Australia, and Pseudocochliobolus australiensis, we show by morphological and molecular phylogenetic analysis that these two specimens represent different species. Taxonomic confusion is resolved by the transfer of Pseudocochliobolus australiensis to Curvularia tsudae comb. nov. et nom. nov., together with a revised synonymy for Curvularia australiensis. © 2014 The Mycological Society of Japan.

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Cultures originally identified as Drechslera australiensis, from seeds of Chloris gayana in Japan, were the basis for Tsuda and Ueyama's new combination, Bipolaris australiensis, and its associated sexual morph Pseudocochliobolus australiensis. By studying ex-type materials of both Drechslera australiensis, which was originally isolated from seeds of Oryza sativa in Australia, and Pseudocochliobolus australiensis, we show by morphological and molecular phylogenetic analysis that these two specimens represent different species. Taxonomic confusion is resolved by the transfer of Pseudocochliobolus australiensis to Curvularia tsudae comb. nov. et nom. nov., together with a revised synonymy for Curvularia australiensis.

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This greenhouse study investigated the efficacy of acibenzolar-S-methyl (Bion®) treatment of lower leaves of passionfruit, (Passiflora edulis f. sp. flavicarpa), on Passionfruit woodiness disease and activities of two pathogenesis-related proteins, chitinase and β-1,3-glucanase after inoculation with passionfruit woodiness virus (PWV). All Bion® concentrations reduced disease symptoms, but the concentration of 0.025 g active ingredient (a.i.)/l was the most effective, reducing disease severity in systemic leaves by 23, 29 and 30 compared with water-treated controls at 30, 40 and 50 days post inoculation (dpi) with PWV, respectively. Correspondingly, relative virus concentration as determined by DAS-ELISA in the upper, untreated leaves (new growth) above the site of inoculation at 50 dpi was reduced by 17 and 22 in plants treated with 0.025 and 0.05 g a.i./l, respectively. Bion® treatment and subsequent inoculation with PWV increased chitinase and β-1,3-glucanase activities in the new leaves above the site of inoculation at 30 dpi with PWV. It was concluded that optimal protective Bion® treatment concentrations were 0.025 and 0.05 g a.i./l.