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Microsporidia are naturally occurring fungal-related parasites that can infect nearly all animal hosts, but their biocontrol potential of insect pests is routinely overlooked in agriculture and forestry. This research brings the first report describing the natural occurrence of a microsporidium causing disease in field-collected populations of the invasive eucalyptus snout beetle, Gonipterus platensis (Coleoptera: Curculionidae), a major destructive pest of eucalyptus plantations in Brazil. Adult beetles were collected during field surveys in commercial eucalyptus plantations in southern Brazil to be examined and dissected with typical symptoms to verify presence of microsporidian spores in haemolymph. From 14 plantations in different sites, the natural infection occurrence in these populations ranged from 0 to 65%, while a lab colony exhibited an infection incidence of 70%. Spore density in haemolymph of symptomatic insects averaged 2.1 (± 0.4) × 107 spores/beetle. Symptoms in infected adults were identified by an abnormal abdomen with malformation of the second pair of wings, impairing their flight activity. Electron transmission microscopy of the pathogen showed morphological features similar to species belonging to the genus Nosema or Vairimorpha. Phylogenetic analysis of the full-length small subunit ribosomal RNA gene suggests this pathogen's placement in the genus Vairimorpha, but with a sequence identity of ~ 94% with the nearest neighbours. The low level of sequence identity suggests this pathogen may represent a novel taxon in the genus and further requires whole genome sequencing for definitive taxonomic resolution. These findings provide insights on the natural occurrence of this novel pathogen of this invasive pest in Eucalyptus plantations in Brazil. Further studies are needed to determine potential of this microsporidium in the design of conservative or augmentative biological control programs for this invasive pest. [ABSTRACT FROM AUTHOR]

Calonectria leaf blight, caused by Calonectria pteridis, is currently one of the main foliar diseases in eucalypt plantations in Brazil. In warm and high rainfall regions, the disease can be a limiting factor for eucalypt production when planting susceptible genotypes. The most effective method for controlling this disease in the field is the use of resistant genotypes, which requires knowledge of the genetic variability and aggressiveness of the pathogen population for effective deployment of plant resistance. This work evaluated the genetic diversity and aggressiveness of C. pteridis populations obtained from infected eucalypt plants in Monte Dourado (Pará state) and Imperatriz (Maranhão state), Brazil. To study the genetic diversity, 16 ISSR primers were tested, five of which amplified polymorphic, reproducible and informative bands. Thirty‐one closely related genotypes were identified from 84 isolates studied, indicating that the population has a low genetic diversity. The aggressiveness of seven isolates, selected according to geographic origin and their clustering in the ISSR‐based dendogram, was determined by inoculation of a hybrid Eucalyptus grandis × E. urophylla clone under controlled conditions. Disease severity was assessed by both measuring the percentage of plant defoliation and assigning a score according to a diagrammatic scale of symptoms. A high correlation between the two evaluation methods was observed, which revealed significant differences in aggressiveness among the isolates. The diagrammatic scale is recommended for disease evaluation because results are obtained much faster, before the occurrence of severe defoliation. No correlation between clustering in the ISSR‐based phylogenetic analysis and aggressiveness was observed. [ABSTRACT FROM AUTHOR]

South African commercial forestry plants mainly Eucalyptus, Pinus and Acacia species. Invertebrate pests play a significant role in the establishment phase of these exotic trees. Whitegrubs, in particular, are known to affect seedling survival during this period. Their pest status and community structure patterns associated with slash and weed management regimes were recently reported for Acacia mearnsii in the KwaZulu-Natal (KZN) province. We tested whether the effects of these regimes were congruent over a wider region (the South African summer-rainfall forestry area), including whitegrubs found on Eucalyptus and Pinus species, or if there were other possible factors that better explained the patterns of assembly. Seventeen trials were established in the KZN and Mpumalanga (MP) provinces from which whitegrubs were collected once a month for a period of one year. Multivariate analyses were performed to determine whitegrub prevalence, distribution, pest ranking and community structure patterns. Sixteen whitegrub morphospecies were found of which Maladera sp. 3, Pegylis sommeri, Schizonycha affinis, Maladera sp. 2, Adoretus ictericus, Maladera sp. 1, and the unknown M8, M12 and M14 had a high pest status with an accumulative prevalence of ∼99%. Maladera sp. 3 was the most prevalent and widespread species. It was also the most important species attacking E. grandis and P. patula, whereas P. sommeri and S. affinis were the most important whitegrubs on A. mearnsii. Clustering analyses showed two spatial (regional [2× clusters] and locality [10×]) and one silvicultural (slash and weed management [9×]) patterns of whitegrub assembly. As expected, the slash and weed management clustered the whitegrub communities in the forestry area. However, the two regional clusters (KZN-Midlands, MP-South and KZN-Coastal) were preferred because they visually represented the whitegrub community distribution with a listing of high-status whitegrub species. This was meaningful enough to suggest the possible implementation of site-specific and practical control strategies. [ABSTRACT FROM AUTHOR]

Ethiopia introduced Eucalyptus spp. in 1895. The most widely planted Eucalyptus species in Ethiopia include E. camaldulensis, E. globulus, E. grandis and E. saligna. Eucalyptus camaldulensis is widely planted between 1250 and 2800 m above sea level, where warm conditions prevail. In recent years, insect infestation has occurred in this species. The aim of this study was to identify the causative agent of this infestation in central Ethiopia. It was found that Glycaspis brimblecombei infested leaves of E. camaldulensis for the first time in our study areas. So far, no infestation of G. brimblecombei has occurred in other Eucalyptus species. In addition to the regular reconnaissance survey on existence and dissemination of G. brimblecombei infestation to other host Eucalyptus spp., the situation strongly urges the country to introduce and employ biological control agents against this threat to the plantations of E. camaldulensis in Ethiopia in order to avoid substantial economic losses to Eucalyptus growers in the country. [ABSTRACT FROM AUTHOR]

The family of Cryphonectriaceae (Diaporthales) includes many important tree pathogens, such as those that cause severe cankers on Eucalyptus trees. Recently, stem canker and cracked bark were observed on 8-yearold Eucalyptus grandis x E. urophylla trees in a plantation in southern China. Fruiting structures typical of Cryphonectriaceae fungi were observed on the surface of the diseased tissues. In this study, the isolated fungi were identified based on DNA sequence analyses and morphological characteristics, and their pathogenicity was tested on three Eucalyptus clones. DNA sequence comparisons of the internal transcribed spacer (ITS) regions (including the intervening 5.8S nrRNA gene), two regions of (S-tubulin (BT2/BT1), and partial translation elongation factorl-a (!TEF-la), indicated that these isolates represent Celoporthe syzygii and one previously undescribed species. The undescribed species was also morphologically distinct from the other species of Celoporthe. The new species was described and named C. cerciana sp. nov. The results of this study based on the ITS, BT2/BT1, and TEF-la sequences indicated that more than one haplotype was isolated from the same Eucalyptus tree. The findings of a previous study, whereby C. eucalypti was isolated from the same plantation as that of this study, revealed the high species diversity of Celoporthe within a single plantation, which is associated with a single Eucalyptus sp. in southern China. The results further suggested that hybridization may occur between C. syzygii and C. eucalypti. In addition to the Eucalyptus trees, C. syzygii was also isolated from native Melastoma candidum in the same Eucalyptus plantation. The inoculation results showed that these fungi isolated from E. grandis x E. urophylla and M. candidum are pathogenic to all three tested E. grandis hybrid clones. Significant differences in tolerance were observed between the tested Eucalyptus clones, suggesting that disease-tolerant Eucalyptus genotypes can be selected for disease management. [ABSTRACT FROM AUTHOR]

The eucalyptus brown looper, Thyrinteina arnobia (Stoll, 1782) (Lepidoptera: Geometridae), is the main lepidopteran defoliator of eucalyptus plantations in Brazil. Outbreaks of this insect pest are common in Brazil and can affect the productivity of planted forests severely. T. arnobia caterpillars from a laboratory colony with viral infection symptoms were analyzed by electron microscopy that revealed polyhedral occlusion bodies (OBs) with several icosahedral virus particles embedded. Analysis of its genetic material showed ten segments of dsRNA, which confirmed this virus as a possible member of the genus Cypovirus . Phylogenetic analysis of the whole genome sequence revealed its close relationship with other isolates of Cypovirus 14 species and according to these results we proposed the name Thyrinteina arnobia cypovirus 14 (TharCPV-14) for this new virus isolate. Further research will be necessary in order to analyze the potential of this virus as a biopesticide. [ABSTRACT FROM AUTHOR]

Despite the importance of invasive pests, few studies address the costs and benefits of the strategies used to control them. The present work assesses the economic impact of the Eucalyptus snout beetle, Gonipterus platensis , and the benefits resulting from its biological control with Anaphes nitens in Portugal, over a 20-year period. Comparisons were made between the real situation (with A. nitens ) and three scenarios without biological control: 1) replacement of Eucalyptus globulus by resistant eucalypts; 2) insecticide use; and 3) offset of yield losses by imported wood. A cost-benefit analysis was performed to evaluate a programme that aimed to accelerate A. nitens establishment. Although A. nitens provides adequate pest control in several regions, 46% of the area planted with eucalypts is affected by the beetle, causing wood losses of 648 M euros over 20 years. Losses in the three hypothetical scenarios were estimated at 2451 M-7164 M euros, resulting in benefits from biological control of 1803 M–6516 M euros, despite the fact that only partial success was achieved. Anticipating biological control by just one, two, or three years resulted in benefit-cost ratios of 67, 190, and 347, respectively. Because nonmarket values were not accounted for, these figures are likely underestimated. [ABSTRACT FROM AUTHOR]

Background: Leaf blight caused by Calonectria spp. is one of the most destructive diseases to affect Eucalyptus nurseries and plantations. These pathogens mainly attack Eucalyptus, a tree with a diversity of secondary metabolites employed as defense-related phytoalexins. To unravel the fungal adaptive mechanisms to various phytoalexins, we examined the genome of C. pseudoreteaudii, which is one of the most aggressive pathogens in southeast Asia. Results: A 63.7 Mb genome with 14,355 coding genes of C. pseudoreteaudii were assembled. Genomic comparisons identified 1785 species-specific gene families in C. pseudoreteaudii. Most of them were not annotated and those annotated genes were enriched in peptidase activity, pathogenesis, oxidoreductase activity, etc. RNA-seq showed that 4425 genes were differentially expressed on the eucalyptus(the resistant cultivar E. grandis×E.camaldulensis M1) tissue induced medium. The annotation of GO term and KEGG pathway indicated that some of the differential expression genes were involved in detoxification and transportation, such as genes encoding ABC transporters, degrading enzymes of aromatic compounds and so on. Conclusions: Potential genomic determinants of phytoalexin detoxification were identified in C. pseudoreteaudii by comparison with 13 other fungi. This pathogen seems to employ membrane transporters and degradation enzymes to detoxify Eucalyptus phytoalexins. Remarkably, the Calonectria genome possesses a surprising number of secondary metabolism backbone enzyme genes involving toxin biosynthesis. It is also especially suited for cutin and lignin degradation. This indicates that toxin and cell wall degrading enzymes may act important roles in the establishment of Calonectria leaf blight. This study provides further understanding on the mechanism of pathogenesis in Calonectria. [ABSTRACT FROM AUTHOR]

Seed predation can cause substantial seed losses and influence plant population dynamics, but the impact depends on the extent to which populations are limited by seed availability or favorable microsites for recruitment. Harvester ants are the dominant post-dispersal seed predators in Australia’s tropical savannas, and their abundance and foraging efficiency, as well as the availability of seed and microsites, are affected by fire history. We undertook a predator-exclusion experiment to examine the interactive effects of fire history (no fire compared with annual burning over 5 years) and seed predation by ants on seedling establishment of the dominant savanna tree, Eucalyptus miniata, in northern Australia. Despite its large seed size, the rate of removal (~ 20-60%) was similar or higher than typically reported for eucalypts, although it was lower than that recorded for the smaller seeds of the co-occurring E. tetrodonta. Seed predation rates were twice as high in annually burnt compared to unburnt sites, but there was no significant difference in the proportion of seedlings that emerged from the initial seed available. Seedling emergence in both regimes was low, representing < 7% of seed available after harvesting. About one-third of emergent seedlings were still alive during the middle of the following dry season. Our results indicate that seedling recruitment in E. miniata is limited by both seed supply and microsite availability. However, seed predation by ants reduces the likelihood of seedling establishment from low to virtually zero, which suggests that it plays a potentially important role in the population dynamics of savanna eucalypts. [ABSTRACT FROM AUTHOR]

Eucalyptus species are indigenous toAustralia but arenowgrown worldwide due to their fast growth rate and various uses as timber and fuel wood. Insect pests of Eucalyptus have since followed their host and, in most cases, leaving behind the natural enemies which usually regulate them below economic injury. This is the case with Glycaspis brimblecombei and Leptocybe invasa which are now resident in most parts of the world including Zimbabwe. Damage as a result of the two pests currently poses a threat to reforestation efforts to provide alternative sources of firewood for curing tobacco. The objective of this study was to determine the distribution of the two pests as well as assess the possibility of managing L. invasa through biological control by releasing and recovering successive generations of the natural enemy Selitrichodes neseri in selected L. invasa-infested areas. Surveys were therefore carried out in Zimbabwe and GPS coordinates for pest presence recorded and used to determine the current distribution and future projections of the two pests using Maximum Entropy (maxent) ecological niche modelling. In preliminary studies to manage L. invasa, the natural wasp enemy S. neseri was released in Eucalyptus plantations and recovery studies done to establish their perpetuation in the field. Based on temperature and precipitation averages for Zimbabwe, the model predicted widespread distribution of the two pests especially in Mashonaland West, Bulawayo, Harare, Midlands province and parts of Manicaland province. This predicted range was projected to shrink due to climate change by the year 2055. In terms of relative contribution in predicting the distribution of the occurrence data, the three most important variables were mean annual temperature (39 %), mean temperature coolest month (18.3%)and annual moisture index (18 %). The performance of the model was high, with an AUC value of 0.884. Selitrichodes neseri wasps were recovered in infested Eucalyptus samples 4–6 generations after the initial release, indicating a high possibility of the natural enemy being able to establish in the future. Our findings are therefore important in understanding the current and projected distribution of both L. invasa and G. brimblecombei in Zimbabwe and formulating management measures for the two pests. [ABSTRACT FROM AUTHOR]

Summary: In June 2016, pot‐grown Eucalyptus gunnii plants showing typical symptoms of powdery mildew disease were found in a greenhouse in Korea. Morphological characteristics of the anamorph and molecular sequence analyses of the ITS regions and 28S rDNA verified the fungus as Erysiphe alphitoides, which is known as common and widespread powdery mildew on Quercus spp. Although E. alphitoides has been reportedly associated with powdery mildew diseases of tropical trees and shrubs other than Quercus spp., this is the first finding of E. alphitoides on a Eucalyptus tree worldwide. [ABSTRACT FROM AUTHOR]

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Numerous species in the Cryphonectriaceae have been recorded on the Myrtales and many of these are economically important pathogens of Eucalyptus. Some species have also recently been shown to be endophytes of native Myrtaceae and to have undergone host jumps to infect Eucalyptus species established as exotics in plantations. Recent surveys in the GuangDong and HaiNan Provinces of South China reveal the presence of a species of Cryphonectriaceae associated with cankers on trees of Lagerstroemia speciosa (Lythraceae, Myrtales). Fungal structures were observed on the surface of dead bark covering cankers and on branch stubs. Multigene phylogenetic analyses were conducted based on DNA sequence comparisons of the partial LSU gene, ITS region of the nuclear ribosomal RNA gene and two regions of the β-tubulin ( BT) gene. The results revealed the presence of a previously undescribed genus and species in the Cryphonectriaceae. The fungus is described here as Chrysomorbus lagerstroemiae gen. et sp. nov. Inoculation tests showed that it is an aggressive pathogen on L. speciosa and that it can also infect Eucalyptus. [ABSTRACT FROM AUTHOR]

A computer-based tool (PRONTI; Priority Ranking Of Non-Target Invertebrates) has been developed to assist the selection of invertebrate species for risk-assessment testing with entomophagous biological control agents (BCAs). PRONTI was used to produce a prioritised list of taxa for host-range testing with the braconid parasitoid Eadya daenerys, a potential BCA for the eucalypt pest, Paropsis charybdis. The resulting list was compared with a list developed using traditional species selection methods. Seven of the nine species on the traditional list were in the PRONTI top 20. The remaining two species (Agasicles hygrophila and Cassida rubiginosa) may not have been selected if the PRONTI tool had been used. These two species were on the traditional list because they are in the same family as the target and are considered valuable BCAs. Alternative BCAs were prioritised by PRONTI. The other 13 taxa prioritised by PRONTI were not on the traditional list: the taxa are little- known natives in the target subfamily or sister subfamily but larvae are presumed to be root-feeders, whereas target larvae are leaf-feeders. PRONTI can support the traditional approach by providing transparent evidence to support the selection (or rejection) of non- target species for host-range testing. [ABSTRACT FROM AUTHOR]

Eucalyptus dieback is a physiological disorder characterized by lesions on the apex of the branches and the death of the shoot apex. Some clones are considered tolerant to this disorder, although, up to now, there are no reports on the use of phenotypic markers for selecting tolerant material. The use of phenotypic markers may contribute to an efficient selection, where the estimation of genetic parameters of the candidate markers are essential to knowledge of the population structure, the genetic potential and effectiveness of markers as selection criteria. In this study, we estimated the genetic parameters of morphological and nutritional markers in 13 commercial eucalyptus clones aiming early selection of tolerant genotypes to eucalyptus dieback. Estimates of the genetic parameters of all characteristics were obtained by the mixed model methodology, REML (Restricted Maximum Likelihood)/BLUP (Best Linear Unbiased Prediction) procedure. Water deficit, one of the factors that promote this disorder, was simulated in eucalyptus cuttings conducted in a greenhouse. Simulated water stress was carried out for 12 weeks by applying polyethylene glycol at different concentrations and by limiting water applied to seedlings. In order to select the most promising markers, 34 morphological and nutritional variables were evaluated for early selection and discrimination of genotypes tolerant to eucalyptus dieback and water deficit. Among the 34 evaluated characteristics, plant height, stem diameter, height increment, leaf area, N, K and B, exhibited significant heritability and high accuracy (greater than 70%). Promising phenotypic markers were identified for early selection of genotypes tolerant to water deficit and eucalyptus dieback. Tolerant clones were pooled and correctly discriminated from the susceptible ones under stressful conditions by the use of seven phenotypic markers in REML/BLUP analysis, selection index ranking and graphic dispersion analysis. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the decay potential of fungi isolated from plantations of Eucalyptus spp. for biological stump removal. Therefore, an accelerated decay test was performed with fungi isolated from stumps of Eucalyptus spp.: Phanerochaete chrysosporium , Cladosporium sp., Penicillium sp., Penicillium implicatum , Resinicium confertum , Trichoderma citrinoviride and Acremonium sp. Chemical analysis of the decayed wood was performed on samples submitted to the most degrading fungi. A field test on eucalyptus stumps, with two methods of inoculation and covering, was performed to evaluate the stumps deterioration by the isolated fungi. Acremonium sp., Cladosporium sp. and P. chrysosporium showed the highest potential in the accelerated decay test. Chemical analysis of the decayed wood indicated the selectivity of fungi for lignin. No significant variations were observed in the field test compared to the control stumps. Biological stump removal shows both environmental and economic potential and needs to be thoroughly studied. [ABSTRACT FROM AUTHOR]

We report the association of Cristulariella moricola (Hino) Redhead with a zonate leaf spot on Eucalyptus benthamii (Myrtaceae). We observed the disease outbreak across a series of experimental E. benthamii plantings in Barnwell County, South Carolina, USA in October 2015. The disease caused nearly complete foliar necrosis of most trees in one experimental planting, but disease incidence remained at low levels (<10% of foliage affected in most trees) in other plantings. Disease development coincided with periods of extended rainfall, which has also been observed in outbreaks of zonate leaf spot caused by C. moricola in other tree species. [ABSTRACT FROM AUTHOR]

Rust is a major Eucalyptus spp. disease, which is especially damaging for early-stage plants. The aim of this study was to verify the pre-infection process of Austropuccinia psidii (A. psidii) in the leaves of three phenological stages of Eucalyptus clones with different resistance levels. Plants from the hybrids of Eucalyptus urophylla × Eucalyptus grandis (E. grandis) with variable levels of resistance to this disease were used. The pathogen was inoculated in vitro on abaxial leaf discs of first, third, and fifth leaf stages and maintained under conditions suitable for disease development. Subsequently, samples from these discs were collected 24 and 120 h after inoculation and processed using scanning electron microscopy analysis. No symptoms were seen in any leaf stage of the resistant clone. Additionally, a low incidence of A. psidii germination (1.3–2%) and appressoria (0–0.5%) in three leaf stages was observed. However, the first leaf stage of the susceptible clone presented germination of large numbers of urediniospores (65%) with appressoria (55%) and degradation of the cuticle and wax. From the third stage, the percentage of germinated urediniospores (<15%) and appressoria (<2%) formation of this clone decreased. Protrusions on the leaf surface, associated with the pathogen, were observed on the first and third leaf stages of the resistant clone and on the fifth stage of the susceptible clone, suggesting a possible defensive plant reaction. [ABSTRACT FROM AUTHOR]

The Botryosphaeriaceae are opportunistic pathogens mostly of woody plants, including Eucalyptus . These fungi can cause cankers and die-back diseases on non-native Eucalyptus trees in South African plantations. Botryosphaeriaceae were isolated from diseased and asymptomatic twigs and leaves from 20 Eucalyptus spp. grown in a Pretoria, South Africa arboretum and its surroundings. The isolates were initially grouped based on conidial morphology and Internal Transcribed Spacer (ITS) rDNA PCR-RFLP profiles. They were further identified using DNA sequence data for the ITS rDNA and translation elongation factor 1-α (TEF-1α) gene regions and tested for pathogenicity. Five species were identified including Botryosphaeria dothidea and four Neofusicoccum species namely Neofusicoccum parvum ; N. cryptoaustrale and N. ursorum that were recently described from plant tissues collected as a part of the current study; and Neofusicoccum eucalypti (Winter) Maleme, Pavlic & Slippers comb. nov. The latter species is recorded for the first time on Eucalyptus in South Africa. Most of the identified species were collected from the leaves of 17 different Eucalyptus spp. Neofusicoccum parvum was most commonly isolated (72% of all isolates) followed by B. dothidea species complex (17%). With exception of N. parvum which was isolated from majority of Eucalyptus spp. the other species were isolated from limited number of Eucalyptus species indicating host-preferences. All the isolated Botryosphaeriaceae species produced lesions on inoculated Eucalyptus grandis plants that were significantly larger than those associated with the controls. [ABSTRACT FROM AUTHOR]

The management of Hylesia nanus Walker (Lepidoptera: Saturniidae), a defoliator of Eucalyptus species (Myrtales: Myrtaceae), was evaluated on the northern coast of Bahia State, Brazil, by performing 3 connected experiments: (1) monitoring of H. nanus moths by using light traps; (2) biological control of H. nanus pupae by releasing the endoparasitoid Palmistichus elaeisis Delvare & La Salle (Hymenoptera: Eulophidae); and (3) chemical control of H. nanus larvae with 1 spraying of bifenthrin + etilenoxi. The light traps effectively assisted the monitoring and control of H. nanus moths, with a mean population peak (± SE) of 801 ± 438 individuals collected per trap in a 23 d nocturnal period. Palmistichus elaeisis was recovered from the H. nanus pupae 96 h post release, with a parasitism rate of 23 ± 3%, indicating an ability to parasitize and contribute to insect suppression. Release of this parasitoid can be integrated with monitoring using light traps. Chemical control was highly effective against the last instar H. nanus larvae, with only 11 ± 3 larval survivors per tree trunk 24 h post spraying. Thus, the monitoring of moths by using light traps, control of pupae by releasing P. elaeisis, and chemical control of last instar larvae are methods that could be integrated into a management plan for H. nanus. [ABSTRACT FROM AUTHOR]

The effects of Teratosphaeria leaf disease ( TLD) on Eucalyptus globulus are varied, and it is currently poorly understood whether infection by TLD can cause long-term growth effects. Such information would greatly assist disease management and pruning regimes on E. globulus plantation sites, resulting in both financial and ecological benefits. Two trials were established to quantify the effects of TLD on long-term growth. The first was a 2-year fungicide exclusion trial that aimed to determine initial growth losses between trees treated with fungicide and untreated trees. It was found that tree growth was not affected until a threshold value of 20% damage was reached. Volume was reduced by 17% between treated and untreated trees over the course of the 2-year trial. The second trial, a 5-year growth study, used differentially affected adjacent stands (one infected and the other unaffected) to look at the longer term effects of more severe defoliation (44-60%) caused by an epidemic of TLD. Results recorded 5 years after the epidemic showed that trees recovered to regain normal growth trajectories after the epidemic, but growth was retarded by ca. 1.2 years for both height and diameter compared with that of the adjoining unaffected stand. As the growth of trees was not permanently reduced by the epidemic, it is concluded that the financial impacts of TLD are more likely to be associated with the loss of income resulting from extensive branch death in the lower crown after leaf and stem infection, which makes the affected stands not suitable for pruning and hence prevents them from being managed as a higher value solid wood crop. [ABSTRACT FROM AUTHOR]

Ralstonia solanacearum sensu lato causes bacterial wilt in many economically important agronomic crops and tree species. Eucalyptus is one of the recorded hosts but, despite the losses to forestry, little is known regarding the disease. The aim of this study was to identify the Ralstonia species that are associated with bacterial wilt of Eucalyptus trees growing in different parts of the world. Phylotyping, sequevar and multilocus sequence analysis were used to identify and determine the genetic diversity of the available isolates. The isolates obtained from Africa and Asia grouped in phylotype I, and those isolates from South America in phylotype II. Following the recent reclassification of R. solanacearum sensu lato, these results show that there are two Ralstonia species associated with bacterial wilt of Eucalyptus, namely, R. solanacearum and R. pseudosolanacearum. The isolates from South America represented R. solanacearum, while those from Africa and Asia were R. pseudosolanacearum. Analysis of the endoglucanase ( egl), transcriptional regulator ( hrpB) and DNA mismatch repair ( mutS) gene regions supported this finding. In addition, one previously unidentified sequevar was identified using partial endoglucanase ( egl) gene sequence analysis of those isolates obtained from Colombia. This study raises questions regarding the aetiology of the two Ralstonia species found on Eucalyptus, their importance relating to quarantine, potential impact and management of the disease with which they are associated. [ABSTRACT FROM AUTHOR]

Thaumastocoris peregrinus(Hemiptera: Thaumastocoridae), the bronze bug, is among the many species of insect pests affecting commercialEucalyptusforests in Brazil.T. peregrinusreduces the photosynthetic ability of trees and in some cases can lead to the complete death of trees. This research aims to assess the potential of freely available medium-resolution Landsat 8 imagery in predicting and mapping attacks caused by the bronze bug inEucalyptusplantations in Brazil using partial least squares discriminant analysis (PLS-DA). The PLS-DA model selected three principal components with a cross-validated error rate of 0.248 for the prediction and mapping of attackedT. peregrinusstands. Important bands were selected from the PLS-DA model using variable importance in the projection (VIP). The VIP bands predicted healthy and attacked stands with an accuracy of 76.7 percent on an independent validation dataset. This study demonstrates the potential of freely available medium-resolution Landsat OLI imagery as an alternative to often expensive high-resolution datasets to successfully characterize and mapT. peregrinusattacks in plantation forests in Brazil. [ABSTRACT FROM PUBLISHER]

Eucalyptus leaf blight caused by Calonectria spp. is a serious disease in Eucalyptus seedling and plantations. However, the molecular mechanisms of the infection process and pathogenesis of Calonectria to Eucalyptus is not well-studied. In this study, we analyzed the transcriptomes of C. pseudoreteaudii at three stages of Eucalyptus leaf infection, and in mycelium grown in potato dextrose broth using Illumina RNA-Seq technology. We identified 161 differentially expressed genes between C. pseudoreteaudii from leaf and mycelium grown in potato dextrose broth. GO and KEGG enrichment analyses of these genes suggested that they were mainly involved in oxidoreductase activity, hydrolase activity, and transmembrane transporter activity. Most of the differentially expressed genes at the early infection stage were upregulated. These upregulated genes were mainly involved in cell wall hydrolysis and toxin synthesis, suggesting a role for toxin and cell wall hydrolases in the establishment of Calonectria leaf blight. Genes related to detoxification of phytoalexins were continually upregulated during infection. The candidate effectors and putative pathogenicity determinants identified in this study will help in the functional analysis of C. pseudoreteaudii virulence and pathogenicity. [ABSTRACT FROM AUTHOR]

Co-evolved plant pathogens play an important role in shaping natural ecosystems. However, plants used in agriculture and forestry have been distributed globally, and their associated pathogens have moved with them. Eucalypts constitute the largest component of global hardwood plantations, and they are increasingly plagued by numerous pathogens, all of which are inconsequential in the native forests. Eucalypts provide a particularly interesting model to study tree diseases because plantations have been established in countries where these trees are exotic but also in Australia adjacent to native eucalypt forests. These situations present opportunities for pathogen movement between the two systems. We present seven different scenarios considering pathogen movement, important disease epidemics, and biosecurity risks, illustrated with examples of well-known eucalypt pathogens and research largely from our laboratories. The overview shows that vigilant biosecurity is required to protect the biodiversity of native forests and the sustainability of eucalypt plantations. [ABSTRACT FROM AUTHOR]

Teratosphaeria destructans and T. viscida are serious pathogens causing leaf, bud and shoot blight diseases of Eucalyptus plantations in the subtropics and tropics of South-East Asia (T. destructans) and North Queensland, Australia (T. viscida). During disease surveys in northern Western Australia and the Northern Territory of Australia, symptoms resembling those of T. destructans were observed on young and adult leaves of native and plantation Eucalyptus spp. and its hybrids. Phylogenetic studies revealed Teratosphaeria species associated with these symptoms are new taxonomic novelties described here as T. novaehollandiae and T. tiwiana spp. nov. Isolates from previous records of T. destructans recorded in Australia were re-examined and based upon the phylogenetic evidence are reassigned to these new taxa. We conclude that T. destructans is absent from Australia. [ABSTRACT FROM AUTHOR]

The objective of this experiment was to evaluate the effect of priming on the germination of Eucalyptus urophylla and of hybrid E. urophylla × E. grandis seeds under salt stress. Two osmotic potentials (-1.0 and -1.5 MPa) were tested, using PEG 6000 for 1 and 3 days. After priming, seeds were germinated under salt stress in a NaCl solution at 0.0 (control), -0.5, -0.75 and -1.0 MPa potentials, at 25 °C. Seed germination and germination speed index decreased as the water potential of the germination medium decreased. However, E. urophylla was more tolerant to salt stress; it showed a higher germination percentage under all tested potentials, when compared to the hybrid. The osmotic conditioning at -1.0 MPa for three days was more effective when E. urophylla x E. grandis was germinated in a salt solution at -1.0 MPa, indicating that this treatment was more effective in inducing tolerance to salt stress. [ABSTRACT FROM AUTHOR]

Fipronil is an insecticide used for termite control in forest plantations. Although pest species need to be restricted, the effects on non-target termites are unknown. The effects of fipronil application on the termite community composition, species richness and functional group diversity were assessed in four different treatment plots (new eucalyptus plantations respectively treated and untreated with fipronil; naturally regenerating secondary forest and the parent native Brazilian savanna) at three different times (90 days before and 90 and 180 days following) clonal seedling planting. A total of 53 termites species belongs to families Termitidae and Rhinotermitidae were collected. The mean richness of termite species differed significantly among the treatments and times. Grass feedings showed the highest overall richness in the plot under natural regeneration 90 days before planting. Soil feedings had higher richness in the control treatment (native savanna) and in the plot under regeneration at 180 days after planting. No significant differences in richness of wood feedings termites were detected in any comparison. Termite assemblage composition in the new eucalyptus plantations did not differ between the fipronil-treated and fipronil-untreated plots. [ABSTRACT FROM AUTHOR]

The article offers information on South African Eucalyptus' non-native infecting insect pests. Topics discussed include introduction of non-native insects through transportation of goods across the countries and cultivated regions' global homogenisation; reporting of six different species of pests like Glycaspis brimblecombei Moore, Ophelimus maskelli Ashmead and Psyllaephagus bliteus Riek; life history and feeding information of all the pests; and their impact on forestry industry.

Leptocybe invasa is a recently introduced forest pest, responsible for significant economic loss in Eucalyptus spp. plantations worldwide. The obj ective of this work is to report its presence in Uruguay, providing data of its distribution and biology. A survey for galls was conducted from 2013 to 2015. The presence of galls was confirmed in 15 out of 35 surveyed points and four out of 157 traps. Eucalyptus benthamii was recorded as a new host. Three periods of emergence were observed. Life cycle was completed only in E. tereticornis,E. camaldulensis andE. grandis. [ABSTRACT FROM AUTHOR]

In the mid-1970s, Mozambique embarked on several forestry projects to promote and establish large plantation areas with eucalypt trees. The planted species includedCorymbia citriodora,Eucalyptus camaldulensis,E. salignaandE. tereticornis. Similar to other regions of the world, pests and pathogens pose a significant threat to eucalypt plantations in Mozambique, but little is known regarding the diseases of trees in the country. The aim of this study was to provide the first detailed consideration of the possible disease problems affecting plantation- grown eucalypt species in the central and northern provinces of Mozambique. Isolates of fungal pathogens were obtained from material displaying disease symptoms collected during two field surveys conducted in 2010 and 2011. Representative fungal isolates were identified using DNA sequence data. Stem canker diseases caused by fungi in the Botryosphaeriaceae, Cryphonectriaceae and Teratosphaeriaceae, as well as leaf spots caused by species ofCalonectria,Pilidiella,PilidiumandPhakopsora myrtacearumwere commonly encountered. Their relative importance to the future of planation forestry in Mozambique is discussed. [ABSTRACT FROM PUBLISHER]

Chrysoporthe austroafricana (Cryphonectriaceae) is a damaging canker pathogen on Eucalyptus species in Southern Africa. Recent studies have shown that the fungus occurs on native Syzygium species and that it has apparently undergone a host range expansion from these native trees to infect non-native Eucalyptus . The aim of this study was to consider whether Chr. austroafricana and other Cryphonectriaceae might exist as endophytes in native Myrtaceae, providing a source of inoculum to infect non-native Myrtales. Healthy branches were collected from Myrtaceae in Mozambique, incubated in florist foam, allowed to dry gradually and monitored for the appearance of fruiting bodies resembling species in the Cryphonectriaceae. Isolates were identified based on DNA sequence data. Two species in the Cryphonectriaceae were obtained, representing the first evidence that species in the Cryphonectriaceae occur as endophytes on native Myrtales, thus providing a source of inoculum to infect non-native and susceptible trees. This has important implications regarding the movement of planting stock used by ornamental tree and forestry enterprises. [ABSTRACT FROM AUTHOR]

1. Foliar colour changes with age and, as a consequence, reflects the internal physiology of leaves. Anthocyanins are 'red' pigments known for their photoprotective role in young leaves and have been suggested to influence the host-finding behaviour of insect herbivores. The existence of colour vision in some species of Eucalyptus-feeding psyllid provides evidence for the possibility of them being able to locate and select leaves based on their age. 2. The preferences of three psyllid species, namely Anoeconeossa bundoorensis, Glycaspis brimblecombei, and Ctenarytaina bipartita, for leaf colours were tested using live leaves of different age, presented without olfactory cues. Changes in foliar pigment concentrations and relationships with amino acid composition in these psyllid's hosts, namely Eucalyptus camaldulensis and Eucalyptus kitsoniana, were studied to consider the adaptive significance of selecting leaves based on their age. 3. The preference for and attraction to young, anthocyanic leaves of two red-sensitive psyllid species ( A. bundoorensis and G. brimblecombei) were demonstrated, whilst the green-yellow-sensitive species ( C. bipartita) was shown to discriminate between young 'yellow' and older 'green' leaves. Age-related variation in leaf colour was positively correlated with greater availability of essential amino acids. 4. This study presents a unique example of herbivore attraction to 'red' leaves and strong evidence for reliance on colour vision in insect orientation at the within-host level. [ABSTRACT FROM AUTHOR]

Calonectria leaf blight ( CLB), caused by Calonectria pteridis, is a major foliar disease of eucalypt plantations in warm and high rainfall regions in Brazil. The use of resistant genotypes is the best method for disease control in the field, so identification of sources of resistance is strategic for the long-term genetic breeding programmes of eucalypt. In this study, resistance of 13 species of Eucalyptus and 3 species of Corymbia to CLB was evaluated by spray inoculation of a spore suspension (1 × 104 conidia ml−1) of the pathogen, under controlled conditions. Eucalyptus brassiana, E. saligna, E. scias and E. agglomerata were the most resistant, while E. robusta, E. urophylla, E. camaldulensis, E. longirostrata and C. toreliana were moderately resistant and E. cloeziana, E. pellita, E. tereticornis, E. pilularis, C. maculata, E. grandis, E. dunnii and C. citriodora were the most susceptible. The broad inter and intraspecific variability of the species tested demonstrates the potential for introgression of resistance genes into valuable genotypes as a strategy for the breeding programmes and commercial plantation of eucalypt. [ABSTRACT FROM AUTHOR]

The Eucalyptus pathogen Quambalaria eucalypti has been reported from several subtropical and tropical countries of the Southern Hemisphere. During the course of a nationwide monitoring programme aimed at the detection of pathogens in commercial eucalypt plantations in Portugal, Q. eucalypti was found affecting Eucalyptus globulus. The identity of the pathogen was confirmed by sequence analyses of the internal transcribed spacer ( ITS) region of the rDNA operon, as well as morphological characteristics. Quambalaria eucalypti is widespread throughout the eucalypt-producing areas of Portugal. Pathogenicity studies revealed that different host genotypes showed various degrees of susceptibility to the pathogen. To our knowledge, this is the first report of Q. eucalypti on Eucalyptus spp. in Portugal and in the Northern Hemisphere. [ABSTRACT FROM AUTHOR]

Outbreaks of a rust disease in eucalypt forestry plantations and nurseries in Kenya, Mozambique and South Africa occurred between 2009 and 2014. The pathogen was identified using morphology and molecular phylogenetic analyses as an undescribed species in the Phakopsoraceae. A systematic study, based on nuclear ribosomal DNA, showed that it is a species of Phakopsora, herein named Phakopsora myrtacearum sp. nov. This new species of rust is the second validly described species on Eucalyptus, along with Puccinia psidii. Phakopsora myrtacearum is distinguished from P. psidii by leaf symptoms, morphology of the urediniospores and distinct phylogenetic placement. Phakopsora myrtacearum has been found on three species of Eucalyptus in Kenya, Mozambique and South Africa, and it may have future negative implications for commercial forestry in these areas. [ABSTRACT FROM AUTHOR]

Puccinia psidii sensu lato (s.l.) is the causal agent of eucalyptus and guava rust, but it also attacks a wide range of plant species from the myrtle family, resulting in a significant genetic and physiological variability among populations accessed from different hosts. The uredospores are crucial to P. psidii dissemination in the field. Although they are important for the fungal pathogenesis, their molecular characterization has been poorly studied. In this work, we report the first in-depth proteomic analysis of P. psidii s.l. uredospores from two contrasting populations: guava fruits (PpGuava) and eucalyptus leaves (PpEucalyptus). NanoUPLC-MSE was used to generate peptide spectra that were matched to the UniProt Puccinia genera sequences (UniProt database) resulting in the first proteomic analysis of the phytopathogenic fungus P. psidii. Three hundred and fourty proteins were detected and quantified using Label free proteomics. A significant number of unique proteins were found for each sample, others were significantly more or less abundant, according to the fungal populations. In PpGuava population, many proteins correlated with fungal virulence, such as malate dehydrogenase, proteossomes subunits, enolases and others were increased. On the other hand, PpEucalyptus proteins involved in biogenesis, protein folding and translocation were increased, supporting the physiological variability of the fungal populations according to their protein reservoirs and specific host interaction strategies. [ABSTRACT FROM AUTHOR]

Plantation forestry in Colombia is based mainly on non-native species of Pinus and Eucalyptus. Since 2008, a disease with symptoms similar to those of dothistroma needle blight ( DNB) has been found affecting large areas planted to Pinus spp. The aim of this study was to identify the causal pathogen as well as to document the levels of disease incidence and severity. Isolates from each of three forestry zones, collected from different host species, were compared based on rDNA sequence of the ITS regions. These were conclusively identified as Dothistroma septosporum, one of two Dothistroma spp. known to cause DNB. Susceptibility was greatest on low elevation Pinus tecunumanii followed by Pinus kesiya and Pinus oocarpa. Pinus maximinoi and high elevation P. tecunumanii showed tolerance to D. septosporum. The disease incidence in the different zones varied significantly with the North zone being the most severely affected. This constitutes the first report of disease distribution and susceptibility of hosts, as well as the first consideration of the relative importance of D. septosporum in Colombia. [ABSTRACT FROM AUTHOR]

Ceratocystis wilt caused by Ceratocystis fimbriata is currently one of the most important diseases affecting Eucalyptus in Brazil. This disease is controlled by planting resistant clones; however, possible variability in the pathogen population may compromise the selection of resistant genotypes. Therefore, this study aimed to evaluate the aggressiveness of C. fimbriata isolates obtained from Eucalyptus spp, as well as their cultural characteristics and genetic variation of their ITS rDNA gene region. We found a significant isolate × clone interaction, with the isolate RM35 being the most aggressive and presenting a broader spectrum of aggressiveness, causing greater xylem discoloration on a larger number of clones. This isolate is the most suitable for artificial inoculations focusing on the selection of resistant materials. Clones CLR-236 and CLR-212 were identified as the most resistant and clones CLR-223 and CLR-240 as the most susceptible and those that are recommended as reliable comparators in artificial inoculations. All isolates were morphologically similar and differed from C. fimbriata from sweet potato by the formation of a wide mouth endoconidiophore that produces doliform endoconidia. According to the culture media and temperature applied, the most favourable conditions for mycelial growth were observed using malt extract agar (MEA) and temperatures ranging from 24 to 26°C. There was no correlation between sporulation and aggressiveness. Great variation in ITS sequences was observed, and a total of five ITS genotypes were identified among the ten isolates tested. [ABSTRACT FROM AUTHOR]

Species of Lasiodiplodia are important pathogens of a wide variety of plants covering a wide geographical distribution. These fungi can be associated with different symptoms such as stem cankers, shoot blights, fruit rots, dieback and gummosis. Diseases caused by Lasiodiplodia were surveyed on Eucalyptus urophylla × grandis, Polyscias balfouriana and Bougainvillea spectabilis in a nursery in southern China. Based on morphology characteristics and phylogenetic analyses of ITS rDNA sequences and translation elongation factor 1-alpha (TEF-1 α) gene regions, four species of Lasiodiplodia were identified. Lasiodiplodia theobromae was identified from E. urophylla × grandis, P. balfouriana and B. spectabilis. L. hormozganensis, L. iraniensis and L. pseudotheobromae were identified from B. spectabilis. To our knowledge, with the exception of L. theobromae on E. urophylla × grandis, this study represents the first report of these fungi on the host plants. Pathogenicity tests showed that all Lasiodiplodia spp. obtained in this study are virulent to E. urophylla × grandis and B. spectabilis, and L. theobromae was virulent to P. balfouriana. [ABSTRACT FROM AUTHOR]

Hyperparasitoids can impede the establishment of primary parasitoid biological control agents or limit their control capacity. Although modern quarantine practices generally prevent hyperparasitoids being introduced with biological control agents, introductions can occur via natural pathways or accidentally with incoming passengers and cargo. In New Zealand, Baeoanusia albifunicle Girault is a self-introduced hyperparasitoid of Enoggera nassaui Girault, an intentionally introduced control agent of the eucalypt pest Paropsis charybdis Stål. A self-introduced primary parasitoid, Neopolycystus insectifurax (Girault), also parasitises P. charybdis in New Zealand. We assessed B. albifunicle biology to better understand its potential to disrupt P. charybdis control. It was determined that B. albifunicle is an obligate solitary hyperparasitoid with a longer lifespan, lower fecundity and longer generation time than its host. The hyperparasitoid reduced effective parasitism by E. nassaui to <10% in the lab, indicating it may limit control of the first P. charybdis generation by slowing spring population growth. It was confirmed that N. insectifurax is not hyperparasitised by B. albifunicle and therefore has some potential to substitute for any hyperparasitoid-driven decline in E. nassaui . [ABSTRACT FROM AUTHOR]

Leptocybe invasa, the blue gum chalcid, is a well-known pest of Eucalyptus globally. Since it was first observed in the Mediterranean and Middle East in 2000, it has spread to other countries where Eucalyptus have been planted. Efforts to control it have included the release of a number of larval and pupal parasitoids. This report serves as the first record of the presence of Quadrastichus mendeli in South Africa, a parasitoid originally released as a biological control agent of L. invasa in Israel. The interactions and potential impacts on the other insects in the L. invasa galls will need to be investigated. [ABSTRACT FROM AUTHOR]

Thaumastocoris peregrinus is a sap-feeding insect native to Australia that has become a serious global pest of Eucalyptus species. To date, T. peregrinus has been found in more than 10 countries across Europe, Africa, South America and Oceania., In the present study, we used the climate modelling software climex (Hearne Scientific Software Pty Ltd, Australia) to predict the potential distribution of T. peregrinus globally and in New Zealand. climex parameters were based on experimental data obtained in the present study and from records collated from the insect's native and invasive distribution., The model of the potential native geographical distribution closely agrees with the known distribution of T. peregrinus and predicts potential expansion into more tropical areas of Australia. In New Zealand, the predicted potential distribution of T. peregrinus matches its current distribution and predicts that, if a suitable host is present, the species will be able to establish in most of the North Island and in northern and eastern regions of the South Island., Globally, the model predicts that many of the world's temperate, Mediterranean and subtropical areas are climatically suitable for establishment of T. peregrinus. This predicted distribution closely matches the global distribution of eucalypt plantations, which are essential for the establishment of this pest., climex projections of potential suitability for T. peregrinus reported in the present study may prove useful for risk assessments and for the identification of areas susceptible to invasion by this pest. [ABSTRACT FROM AUTHOR]

Zimbabwe embarked on plantingEucalyptusspecies in the early 1900s. Based on a robust breeding programme, it has become a major source of seed for other countries in and outside Africa. Tree health surveys conducted onEucalyptusin some east and southern African countries over the past two decades have revealed several important fungal diseases that were previously not known in the region, but little is known regarding these problems in Zimbabwe. The aim of this study was to identify importantEucalyptusdiseases across Zimbabwe's agroclimatic regions. Morphological characteristics and DNA sequence data were used to identify pathogens collected to species level. Widespread stem canker diseases, caused by species belonging to the Botryosphaeriaceae and Teratosphaeriaceae, and leaf spot diseases caused by fungi in the Capnodiales, were identified. Armillaria root and stem rot was restricted to a single site in the Eastern Highlands. Fungi that could cause canker or blue stain of timber were isolated from recently harvested stumps and included species ofCeratocystisandOphiostoma. This study is the first to identifyEucalyptuspathogens to species level in Zimbabwe and we report for the first time the presence of the stem canker pathogenT. gauchensisin southern Africa. The results will provide a foundation for the formulation of future disease management strategies in the country. [ABSTRACT FROM PUBLISHER]

This study aimed to elucidate the infection process of Botrytis cinerea on eucalypt leaves. Tests were conducted to evaluate the influence of leaf side (adaxial or abaxial), leaf age and luminosity on conidial germination, appressorium formation and grey mould (GM) severity. The adaxial and abaxial surfaces of detached eucalypt leaves were inoculated with a conidial suspension of B. cinerea and kept under constant light or dark. Subsequently, the adaxial surface of young and old leaves was inoculated and kept in the dark. To evaluate the percentage of conidia germination and appressorium formation, leaf samples were collected 6 hours after inoculation (hai), clarified (alcohol and chloral hydrate) and evaluated under a light microscope. The severity of GM was assessed 10 days after inoculation. For scanning electron microscopy analysis, samples were collected from 2 to 168 hai. A higher percentage of conidia germination (92%) and GM severity (21%) occurred on the adaxial surfaces of leaves kept in the dark. There was no statistical difference between the surfaces of young and old leaves for conidia germination. No appressorium was formed by B. cinerea. The GM severity on young leaves (17.3%) was 34 times higher than on old leaves (0.5%). The micrographs showed germinating conidia emitting 1-4 germ tubes in samples at 4 hai. The fungus penetration occurred through intact leaf surfaces, and both extra- and intracellular colonization of the mesophyll cells by the hyphae of the pathogen were observed at 120 hai. Sporulation occurred on the adaxial and abaxial surfaces (macronematous conidiophores) and below the epidermis (micronematous conidiophores). [ABSTRACT FROM AUTHOR]

Two eucalypt-feeding psyllids (Hemiptera: Psylloidea: Aphalaridae): the eucalypt shoot psyllid, Blastopsylla occidentalis Taylor and the red gum lerp psyllid, Glycaspis brimblecombei Moore are reported from Israel for the first time. Both species belong to Spondyliaspidinae, a subfamily of jumping plant lice that feed generally on Myrtaceae, mainly eucalypts. The psyllids were collected from Eucalyptus camaldulensis Dehnh., a dominant eucalypt species in Israel. A summary of the global distribution and the host trees of the two psyllids are provided and their potential threat to eucalypts in Israel is discussed. Diagnostic information to distinguish between the two psyllids is presented, with an identification key for the adults of six eucalypt-feeding psyllid species in the Western Palearctic region. [ABSTRACT FROM AUTHOR]

The pre-release risk assessment, a recommended practice in biological control programmes, was carried out before introducing Closterocerus chamaeleon (Girault), a eulophid parasitoid of the eucalypt gall maker Ophelimus maskelli (Ashmead) (Hymenoptera, Eulophidae), in Sicily, Italy. We evaluated its host specificity in laboratory small arena no-choice tests on six non-target hosts, using O. maskelli as a control species. The non-target species fit with at least one of the following criteria: a) common geographical origin; b) ecological or behavioural affinities with the target host; c) concealed habit of the preimaginal stages; d) taxonomic affinity; e) taxonomic affinity with hosts of congeneric parasitoids of the candidate agent; and f) presence in Italy/Sicily. Closterocerus chamaeleon performed an oviposition sequence of 10 recognisable behaviours, always leading to parasitization when exposed to O. maskelli. The same behaviour sequence was carried out on the gall maker Leptocybe invasa Fisher et La Salle, the only non-target species living on Eucalyptus, but just until Step 6, i.e. until ovipositor extraction and insertion, and never until egg-laying. All of the other non-target hosts were ignored. Furthermore, the adult parasitoid longevity was assessed in three rearing conditions: 1) no food/no parasitisation permitted; 2) food/no parasitisation permitted; and 3) food provided after parasitisation. Adult wasp longevity was significantly higher in treatment 2 (21.1 days ± 4.1 SE) than in treatment 1 (3.6 days ± 0.5 SE) or 3 (3.8 days ± 0.6 SE). Laboratory tests carried out in this study on C. chamaeleon indicated high host selection ability, later confirmed by our post-release field data. [ABSTRACT FROM AUTHOR]

Novel species of fungi described in the present study include the following from Malaysia: Castanediella eucalypti from Eucalyptus pellita, Codinaea acacia from Acacia mangium, Emarcea eucalyptigena from Eucalyptus brassiana, Myrtapenidiella eucalyptorum from Eucalyptus pellita, Pilidiella eucalyptigena from Eucalyptus brassiana and Strelitziana malaysiana from Acacia mangium. Furthermore, Stachybotrys sansevieriicola is described from Sansevieria ehrenbergii (Tanzania), Phacidium grevilleae from Grevillea robusta (Uganda), Graphium jumulu from Adansonia gregorii and Ophiostoma eucalyptigena from Eucalyptus marginata (Australia), Pleurophoma ossicola from bone and Plectosphaerella populi from Populus nigra (Germany), Colletotrichum neosansevieriae from Sansevieria trifasciata, Elsinoë othonnae from Othonna quinquedentata and Zeloasperisporium cliviae (Zeloasperisporiaceae fam. nov.) from Clivia sp. (South Africa), Neodevriesia pakbiae, Phaeophleospora hymenocallidis and Phaeophleospora hymenocallidicola on leaves of a fern (Thailand), Melanconium elaeidicola from Elaeis guineensis (Indonesia), Hormonema viticola from Vitis vinifera (Canary Islands), Chlorophyllum pseudoglobossum from a grassland (India), Triadelphia disseminata from an immunocompromised patient (Saudi Arabia), Colletotrichum abscissum from Citrus (Brazil), Polyschema sclerotigenum and Phialemonium limoniforme from human patients (USA), Cadophora vitícola from Vitis vinifera (Spain), Entoloma flavovelutinum and Bolbitius aurantiorugosus from soil (Vietnam), Rhizopogon granuloflavus from soil (Cape Verde Islands), Tulasnella eremophila from Euphorbia officinarum subsp. echinus (Morocco), Verrucostoma martinicensis from Danaea elliptica (French West Indies), Metschnikowia colchici from Colchicum autumnale (Bulgaria), Thelebolus microcarpus from soil (Argentina) and Ceratocystis adelpha from Theobroma cacao (Ecuador). Myrmecridium iridis (Myrmecridiales ord. nov., Myrmecridiaceae fam. nov.) is also described from Iris sp. (The Netherlands). Novel genera include (Ascomycetes): Budhanggurabania from Cynodon dactylon (Australia), Soloacrosporiella, Xenocamarosporium, Neostrelitziana and Castanediella from Acacia mangium and Sabahriopsis from Eucalyptus brassiana (Malaysia), Readerielliopsis from basidiomata of Fuscoporia wahlbergii (French Guyana), Neoplatysporoides from Aloe ferox (Tanzania), Wojnowiciella, Chrysofolia and Neoeriomycopsis from Eucalyptus (Colombia), Neophaeomoniella from Eucalyptus globulus (USA), Pseudophaeomoniella from Olea europaea (Italy), Paraphaeomoniella from Encephalartos altensteinii, Aequabiliella, Celerioriella and Minutiella from Prunus (South Africa). Tephrocybella (Basidiomycetes) represents a novel genus from wood (Italy). Morphological and culture characteristics along with ITS DNA barcodes are provided for all taxa. [ABSTRACT FROM AUTHOR]

The genus Ramularia includes numerous phytopathogenic species, several of which are economically important. Ramularia eucalypti is currently the only species of this genus known to infect Eucalyptus by causing severe leaf-spotting symptoms on this host. However, several isolates identified as R. eucalypti based on morphology and on nrDNA sequence data of the ITS region have recently been isolated from other plant hosts, from environmental samples and also from human clinical specimens. Identification of closely related species based on morphology is often difficult and the ITS region has previously been shown to be unreliable for species level identification in several genera. In this study we aimed to resolve this species-complex by applying a polyphasic approach involving rphology, multi-gene phylogeny and matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS). Six partial genes (ITS, ACT, TEF1-α, HIS3, GAPDH and RPB2) were amplified and sequenced for a total of 44 isolates representing R. eucalypti s.lat. and closely related species. A multi-gene Bayesian phylogenetic analysis and parsimony analysis were performed, and both the resulting trees showed significant support for separation of seven species in R. eucalypti s.lat., including two previously described (R. eucalypti and R. miae), four novel species here described (R. haroldporteri, R. glennii, R. mali and R. plurivora) and one undescribed Ramularia species (sterile). Additionally, Mycosphaerella nyssicola is newly combined in Ramularia as R. nyssicola. Main mass spectra (MSPs) of several R. eucalypti s.lat. strains were generated using MALDI-TOF MS and were compared through a Principal Component Analysis (PCA) dendogram. The PCA dendrogram supported three clades containing R. plurivora, R. glenni /R. mali and R. eucalypti /R. miae. Although the dendrogram separation of species differed from the phylogenetic analysis, the clinically relevant strains were successfully identified by MALDI-TOF MS. [ABSTRACT FROM AUTHOR]

To identify and implement Puccinia psidii control strategies, it is essential to understand the role of environmental factors on rust-disease development and spread among eucalypt ( Eucalyptus spp.) plantations. In this study, we evaluated the wind dispersal of P. psidii urediniospores and the progress of eucalypt rust in a field trial in Brazil. Urediniospores of P. psidii were trapped in a Burkard® spore trap from July 2004 to June 2005. To evaluate the progress of eucalypt rust, plots were established in March 2002 using a clonal hedge scheme. The incidence of both branches and leaves with rust was assessed weekly from February 2003 to October 2005. Disease progress was studied using time-series analysis. Urediniospores were trapped on 77% of the days sampled. The highest average urediniospore concentration was detected from July to November, and most of the urediniospores (58%) were trapped at night. Urediniospore concentration was negatively correlated with rainfall, light intensity, minimum, average and maximum temperatures and wind speed, whereas urediniospore concentration was positively correlated with leaf-wetness duration and relative humidity. From December 2004 to June 2005, average urediniospore concentration was 0.22 spores m−3 air h−1 and had no correlation with meteorological data. The highest average urediniospore concentration was associated with a combination of low average temperature, low light intensity, low wind speed, high relative humidity and high leaf wetness, which reflect conditions observed at night. The disease incidence was positively correlated with the urediniospores trapped at 12 days prior to disease assessment. According to the models obtained by the time series, a seasonal yearly effect was found on rust progress. Using our models, we were also able to forecast disease incidence up to 3 months after the last field assessment. [ABSTRACT FROM AUTHOR]