Population genetic structure of the brown tiger prawn, Penaeus esculentus, in tropical northern Australia

Eight polymorphic microsatellite loci were analysed in six population samples from four locations of the Australian endemic brown tiger prawn, Penaeus esculentus. Tests of Hardy-Weinberg equilibrium were generally in accord with expectations, with only one locus, in two samples, showing significant deviations. Three samples were taken in different years from the Exmouth Gulf. These showed no significant heterogeneity, and it was concluded that they were from a single panmictic population. A sample from Shark Bay, also on the west coast of Australia, showed barely detectable differentiation from Exmouth Gulf (F (ST) = 0 to 0.0014). A northeast sample from the Gulf of Carpentaria showed low (F (ST) = 0.008) but significant differentiation from Moreton Bay, on the east coast. However, Exmouth Gulf/Shark Bay samples were well differentiated from the Gulf of Carpentaria/Moreton Bay (F (ST) = 0.047-0.063). The data do not fit a simple isolation by distance model. It is postulated that the east-west differentiation largely reflects the isolation of east and west coast populations that occurred at the last glacial maximum when there was a land bridge between north-eastern Australia and New Guinea.

Constructing a new individual-based model of phosphine resistance in lesser grain borer (Rhyzopertha dominica): do we need to include two loci rather than one?

In this article, we describe and compare two individual-based models constructed to investigate how genetic factors influence the development of phosphine resistance in lesser grain borer (R. dominica). One model is based on the simplifying assumption that resistance is conferred by alleles at a single locus, while the other is based on the more realistic assumption that resistance is conferred by alleles at two separate loci. We simulated the population dynamic of R. dominica in the absence of phosphine fumigation, and under high and low dose phosphine treatments, and found important differences between the predictions of the two models in all three cases. In the absence of fumigation, starting from the same initial frequencies of genotypes, the two models tended to different stable frequencies, although both reached Hardy-Weinberg equilibrium. The one-locus model exaggerated the equilibrium proportion of strongly resistant beetles by 3.6 times, compared to the aggregated predictions of the two-locus model. Under a low dose treatment the one-locus model overestimated the proportion of strongly resistant individuals within the population and underestimated the total population numbers compared to the two-locus model. These results show the importance of basing resistance evolution models on realistic genetics and that using oversimplified one-locus models to develop pest control strategies runs the risk of not correctly identifying tactics to minimise the incidence of pest infestation.

The Introduction of Transgenes to Control Blackheart in Pineapple: Biolistics Vs Agrobacterium Transformation, in 'Contributing to a Sustainable Future'

Techniques for the introduction of transgenes to control blackheart by particle bombardment and Agrobacterium co-transformation have been developed for pineapple cv. Smooth Cayenne. Polyphenol oxidase (PPO) is the enzyme responsible for blackheart development in pineapple fruit following chilling injury. Sense, anti-sense and hairpin constructs were used as a means to suppress PPO expression in plants. Average transformation efficiency for biolistics was approximately 1% and for Agrobacterium was approximately 1.5%. These results were considered acceptable given the high regeneration potential of between 80-90% from callus cultures. Southern blot analysis revealed stable integration of transgenes with lower copy number found in plants transformed with Agrobacterium compared to those transformed by biolistics. Over 5000 plants from 55 transgenic lines are now undergoing field evaluation in Australia

Kirramyces viscidus sp. nov., a new eucalypt pathogen from tropical Australia closely related to the serious leaf pathogen, Kirramyces destructans

Kirramyces destructans is a serious pathogen causing a leaf, bud and shoot blight disease of Eucalyptus plantations in the subtropics and tropics of South-East Asia. During surveillance of eucalypt taxa trials in northern Queensland, symptoms resembling those of K. destructans were observed on Eucalyptus grandis and E. grandis × E. camaldulensis. Phylogenetic and morphological studies revealed that the Kirramyces sp. associated with these symptoms represents a new taxon described here as K. viscidus sp. nov., which is closely related to K. destructans. Plantation assessments revealed that while E. grandis from the Copperload provenance, collected in northern Queensland, recovered from disease, E. grandis × E. camaldulensis hybrids from South America were highly susceptible to infection by K. viscidus and are not recommended for planting in northern Queensland. Preliminary results suggest the fungus probably originates from Australia. K. viscidus is closely related to K. destructans and causes a disease with similar symptoms, suggesting that it could seriously damage Australian eucalypt plantations, especially those planted off-site.

Host-plant resistance and biopesticides: Ingredients for successful integrated pest management (IPM) in Australian sorghum production

There are two major pests of sorghum in Australia, the sorghum midge, Stenodiplosis sorghicola (Coquillett), and the corn earworm, Helicoverpa armigera (Hübner). During the past 10 years the management of these pests has undergone a revolution, due principally to the development of sorghum hybrids with resistance to sorghum midge. Also contributing has been the adoption of a nucleopolyhedrovirus for the management of corn earworm. The practical application of these developments has led to a massive reduction in the use of synthetic insecticides for the management of major pests of sorghum in Australia. These changes have produced immediate economic, environmental and social benefits. Other flow-on benefits include providing flexibility in planting times, the maintenance of beneficial arthropods and utilisation of sorghum as a beneficial arthropod nursery, a reduction in midge populations and a reduction in insecticide resistance development in corn earworm. Future developments in sorghum pest management are discussed.

Host plant resistance in grain crops and prospects for invertebrate pest management in Australia: An overview

An integrated pest management (IPM) approach that relies on an array of tactics is adopted commonly in response to problems with pesticide-based production in many agricultural systems. Host plant resistance is often used as a fundamental component of an IPM system because of the generally compatible, complementary role that pest-resistant crops play with other tactics. Recent research and development in the resistance of legumes and cereals to aphids, sorghum midge resistance, and the resistance of canola varieties to mite and insect pests have shown the prospects of host plant resistance for developing IPM strategies against invertebrate pests in Australian grain crops. Furthermore, continuing advances in biotechnology provide the opportunity of using transgenic plants to enhance host plant resistance in grains.

Ocean dispersal modelling for propagules of pond apple (Annona glabra L.)

Pond apple invades riparian and coastal environments with water acting as the main vector for dispersal. As seeds float and can reach the ocean, a seed tracking model driven by near surface ocean currents was used to develop maps of potential seed dispersal. Seeds were ‘released’ in the model from sites near the mouths of major North Queensland rivers. Most seeds reach land within three months of release, settling predominately on windward-facing locations. During calm and monsoonal conditions, seeds were generally swept in a southerly direction, however movement turns northward during south easterly trade winds. Seeds released in February from the Johnstone River were capable of being moved anywhere from 100 km north to 150 km south depending on prevailing conditions. Although wind driven currents are the primary mechanism influencing seed dispersal, tidal currents, the East Australian Current, and other factors such as coastline orientation, release location and time also play an important role in determining dispersal patterns. In extreme events such as tropical cyclone Justin in 1997, north east coast rivers could potentially transport seed over 1300 km to the Torres Strait, Papua New Guinea and beyond.

Australian gall-inducing scale insects on Eucalyptus: revision of Opisthoscelis Schrader (Coccoidea, Eriococcidae) and descriptions of a new genus and nine new species.

We revise the genus Opisthoscelis Schrader, and erect the genus Tanyscelis gen. n. with Opisthoscelis pisiformis Froggatt as its type species. Species of both genera induce sexually dimorphic galls on Eucalyptus (Myrtaceae) in Australia, with Opisthoscelis subrotunda Schrader also in Papua New Guinea. We synonymise the following taxa (junior synonym with senior synonym): Opisthoscelis fibularis Froggatt, syn. n. with Opisthoscelis spinosa Froggatt; Opisthoscelis recurva Froggatt, syn. n. with Opisthoscelis maculata Froggatt; Opisthoscelis globosa Froggatt, syn. n. (=Opisthoscelis ruebsaameni Lindinger) with Opisthoscelis convexa Froggatt; and Opisthoscelis mammularis Froggatt, syn. n. with Opisthoscelis verrucula Froggatt. We transfer seven Opisthoscelis species to Tanyscelis as Tanyscelis conica (Fuller), comb. n., Tanyscelis convexa (Froggatt), comb. n., Tanyscelis maculata (Froggatt), comb. n., Tanyscelis maskelli (Froggatt), comb. n., Tanyscelis pisiformis (Froggatt), comb. n., Tanyscelis spinosa (Froggatt), comb. n., and Tanyscelis verrucula (Froggatt), comb. n. We redescribe and illustrate the adult female of each named species of Opisthoscelis for which the type material is known, as well as the first-instar nymph of the type species of Opisthoscelis (Opisthoscelis subrotunda) and Tanyscelis (Opisthoscelis pisiformis). We describe four new species of Opisthoscelis: Opisthoscelis beardsleyi Hardy & Gullan, sp. n., Opisthoscelis thurgoona Hardy & Gullan, sp. n., Opisthoscelis tuberculata Hardy & Gullan, sp. n., and Opisthoscelis ungulifinis Hardy & Gullan, sp. n., and five new species of Tanyscelis: Tanyscelis grallator Hardy & Gullan, sp. n., Tanuscelis megagibba Hardy & Gullan, sp. n., Tanyscelis mollicornuta Hardy & Gullan, sp. n., Tanyscelis tripocula Hardy & Gullan, sp. n., and Tanyscelis villosigibba Hardy & Gullan, sp. n. We designate lectotypes for Opisthoscelis convexa, Opisthoscelis fibularis, Opisthoscelis globosa Froggatt, Opisthoscelis maculata, Opisthoscelismammularis, Opisthoscelis maskelli, Opisthoscelis pisiformis, Opisthoscelis recurva, Opisthoscelis serrata, Opisthoscelis spinosa, and Opisthoscelis verrucula. As a result of our taxonomic revision, Opisthoscelis has six species and Tanyscelis has 12 species. We describe the galls of females for all 18 species and galls of males for 10 species of Opisthoscelis and Tanyscelis, and provide photographs of the galls for most species. A key to the adult females of the species of both genera is included.

Teratosphaeria pseudoeucalypti, new cryptic species responsible for leaf blight of Eucalyptus in subtropical and tropical Australia

Sub-tropical and tropical plantations of Eucalyptus grandis hybrids in eastern Australia have been severely affected by anamorphs of Teratosphaeria (formerly Kirramyces) causing a serious leaf blight disease. Initially the causal organism in Queensland, Australia, was identified as Teratosphaeria eucalypti, a known leaf parasite of endemic Eucalyptus spp. However, some inconsistencies in symptoms, damage and host range suggested that the pathogen in Queensland may be a new species. Isolates of T. eucalypti from throughout its known endemic range, including Queensland and New Zealand, where it is an exotic pathogen, were compared using multiple gene phylogenies. Phylogenetic studies revealed that the species responsible for leaf blight in Queensland represents a new taxon, described here as Teratosphaeria pseudoeucalypti. While the DNA sequence of T. pseudoeucalypti was more similar to T. eucalypti, the symptoms and cultural characteristics resembled that of T. destructans. The impact of this disease in central Queensland has increased annually and is the major threat to the eucalypt plantation industry in the region.

Fungal Planet description sheets: 128-153

Novel species of microfungi described in the present study include the following from Australia: Catenulostroma corymbiae from Corymbia, Devriesia stirlingiae from Stirlingia, Penidiella carpentariae from Carpentaria, Phaeococcomyces eucalypti from Eucalyptus, Phialophora livistonae from Livistona, Phyllosticta aristolochiicola from Aristolochia, Clitopilus austroprunulus on sclerophyll forest litter of Eucalyptus regnans and Toxicocladosporium posoqueriae from Posoqueria. Several species are also described from South Africa, namely: Ceramothyrium podocarpi from Podocarpus, Cercospora chrysanthemoides from Chrysanthemoides, Devriesia shakazului from Aloe, Penidiella drakensbergensis from Protea, Strelitziana cliviae from Clivia and Zasmidium syzygii from Syzygium. Other species include Bipolaris microstegii from Microstegium and Synchaetomella acerina from Acer (USA), Brunneiapiospora austropalmicola from Rhopalostylis (New Zealand), Calonectria pentaseptata from Eucalyptus and Macadamia (Vietnam), Ceramothyrium melastoma from Melastoma (Indonesia), Collembolispora aristata from stream foam (Czech Republic), Devriesia imbrexigena from glazed decorative tiles (Portugal), Microcyclospora rhoicola from Rhus (Canada), Seiridium phylicae from Phylica (Tristan de Cunha, Inaccessible Island), Passalora lobeliaefistulosis from Lobelia (Brazil) and Zymoseptoria verkleyi from Poa (The Netherlands). Valsalnicola represents a new ascomycete genus from Alnus (Austria) and Parapenidiella a new hyphomycete genus from Eucalyptus (Australia). Morphological and culture characteristics along with ITS DNA barcodes are also provided. © 2012 Nationaal Herbarium Nederland & Centraalbureau voor Schimmelcultures.

New distribution and lure records of Dacinae (Diptera: Tephritidae) from Queensland, Australia, and description of a new species of Dacus Fabricius

New distribution records for 42 species of fruit flies (Diptera: Tephritidae: Dacinae) in Queensland are presented, resulting from exotic fruit fly monitoring from 1996 to 2011. Summaries of previously known Australian distributions are provided. Fruit flies were collected at cue lure and methyl eugenol traps and reared from host fruit. No new distributions south of Townsville were recorded for the economic species Bactrocera frauenfeldi (Schiner, 1868), Bactrocera kraussi (Hardy, 1951) and Bactrocera musae (Tryon, 1927). Minor range extensions are noted for Bactrocera neohumeralis (Hardy, 1951) and Bactrocera tryoni (Froggatt, 1897). Bactrocera jarvisi (Tryon, 1927) is recorded being weakly attracted to cue lure in Queensland and the first lure record (one specimen from cue lure) is provided for Dacus (Mellesis) petioliforma (May, 1956). Taxonomic issues with Bactrocera melanothoracica Drew (1989) and Bactrocera unirufa Drew (1989) are discussed. Dacus (Neodacus) coenensis sp. n. is described and illustrated from Cape York Peninsula.

Western white gum (plantations)

Western white gum produces a hard, heavy, durable and attractive timber that is potentially suitable for construction, appearance products and round timber products. It is no longer harvested from natural stands but is a productive plantation tree in Queensland. It is highly suitable for low rainfall areas in northern Australia and is frost and drought hardy, has good form and reasonable growth rates. It is generally unknown in either national or international markets.

Genomic deletions and mutations resulting in the loss of eight genes reduce the in vivo replication capacity of Meleagrid herpesvirus 1

Meleagrid herpesvirus 1 (MeHV-1 or turkey herpesvirus) has been widely used as a vaccine in commercial poultry. Initially, these vaccine applications were for the prevention of Marek’s disease resulting from Gallid herpesvirus 2 infections, while more recently MeHV-1 has been used as recombinant vector for other poultry infections. The construction of herpesvirus infectious clones that permit propagation and manipulation of the viral genome in bacterial hosts has advanced the studies of herpesviral genetics. The current study reports the construction of five MeHV-1 infectious clones. The in vitro properties of viruses recovered from these clones were indistinguishable from the parental MeHV-1. In contrast, the rescued MeHV-1 viruses were significantly attenuated when used in vivo. Complete sequencing of the infectious clones identified the absence of two regions of the MeHV-1 genome compared to the MeHV-1 reference sequence. These analyses determined the rescued viruses have seven genes, UL43, UL44, UL45, UL56, HVT071, sorf3 and US2 either partially or completely deleted. In addition, single nucleotide polymorphisms were identified in all clones compared with the MeHV-1 reference sequence. As a consequence of one of the polymorphisms identified in the UL13 gene, four of the rescued viruses were predicted to encode a serine/threonine protein kinase lacking two of three domains required for activity. Thus four of the recovered viruses have a total of eight missing or defective genes. The implications of these findings in the context of herpesvirus biology and infectious clone construction are discussed.

Genomic deletions and mutations resulting in the loss of eight genes reduce the in vivo replication capacity of Meleagrid herpesvirus 1

Meleagrid herpesvirus 1 (MeHV-1 or turkey herpesvirus) has been widely used as a vaccine in commercial poultry. Initially, these vaccine applications were for the prevention of Marek’s disease resulting from Gallid herpesvirus 2 infections, while more recently MeHV-1 has been used as recombinant vector for other poultry infections. The construction of herpesvirus infectious clones that permit propagation and manipulation of the viral genome in bacterial hosts has advanced the studies of herpesviral genetics. The current study reports the construction of five MeHV-1 infectious clones. The in vitro properties of viruses recovered from these clones were indistinguishable from the parental MeHV-1. In contrast, the rescued MeHV-1 viruses were significantly attenuated when used in vivo. Complete sequencing of the infectious clones identified the absence of two regions of the MeHV-1 genome compared to the MeHV-1 reference sequence. These analyses determined the rescued viruses have seven genes, UL43, UL44, UL45, UL56, HVT071, sorf3 and US2 either partially or completely deleted. In addition, single nucleotide polymorphisms were identified in all clones compared with the MeHV-1 reference sequence. As a consequence of one of the polymorphisms identified in the UL13 gene, four of the rescued viruses were predicted to encode a serine/threonine protein kinase lacking two of three domains required for activity. Thus four of the recovered viruses have a total of eight missing or defective genes. The implications of these findings in the context of herpesvirus biology and infectious clone construction are discussed.

Responses of fruit flies (Tephritidae: Dacinae) to novel male attractants in north Queensland, Australia, and improved lures for some pest species

Male fruit fly attractants, cue-lure and methyl eugenol (ME), have been successfully used for the last 50 years in the monitoring and control of Dacini fruit flies (Bactrocera and Dacus species). However, over 50% of Dacini are non-responsive to either lure, including some pest species. A new lure, zingerone, has been found to weakly attract cue- and ME-responsive species in Malaysia. In Australia it attracted a weakly cue-responsive minor pest Bactrocera jarvisi (Tryon) and three non-responsive' species. Similar compounds were tested in Queensland and attracted cue- and ME-responsive species and two non-responsive' species. In this study, 14 novel compounds, including raspberry ketone formate (RKF) (Melolure) and zingerone, were field tested in comparison with cue-lure and ME at 17 sites in north Queensland. The most attractive novel lures were isoeugenol, methyl-isoeugenol, dihydroeugenol and zingerone. Several non-responsive' species responded to the new lures: Bactrocera halfordiae (Tryon), a species of some market access concern, was most attracted to isoeugenol; B.barringtoniae (Tryon), B.bidentata (May) and B.murrayi (Perkins) responded to isoeugenol, methyl-isoeugenol and dihydroeugenol; two new species of Dacus responded to zingerone. Bactrocera kraussi (Hardy), a cue-responsive minor pest in north Queensland, was significantly more attracted to isoeugenol than cue-lure. The cue-responsive D.absonifacies (May) and D.secamoneaeDrew were significantly more attracted to zingerone than cue-lure. Bactrocera yorkensisDrew & Hancock, a ME-responsive species was significantly more attracted to isoeugenol, methyl-isoeugenol and dihydroeugenol than ME. The preferential response to RKF or cue-lure was species specific. Six species were significantly more attracted to RKF, including the pests B.tryoni (Froggatt), B.frauenfeldi (Schiner) and minor pest B.bryoniae (Tryon); eight species were significantly more attracted to cue-lure including the pest B.neohumeralis (Hardy). These findings have significance in the search for optimal male lures for pest species elsewhere in the world.