Intra-specific variation for host plant use in Helicoverpa armigera (Hubner) (Lepidoptera : Noctuidae) : implications for management

The polyphagous moth Helicoverpa armigera (Hübner) is one of the world's most important agricultural pests. A number of existing approaches and future designs for management of H. armigera rely on the assumption that moths do not exhibit either genetically and/or non-genetically based variation for host plant utilization. We review recent empirical evidence demonstrating that both these forms of variation influence host plant use in this moth. The significance of this variation in H. armigera in relation to current and future pest management strategies is examined. We provide recommendations on future research needs and directions for sustainable management of H. armigera, under a framework that includes consideration of intra-specific variation for host use relevant in this and other similar pest species.

Variability in odour reception in the peripheral sensory system of Helicoverpa armigera (Hubner) (Lepidoptera : Noctuidae)

Mixtures of single odours were used to explore the receptor response profile across individual antennae of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae). Seven odours were tested including floral and green-leaf volatiles: phenyl acetaldehyde, benzaldehyde, β-caryophyllene, limonene, α-pinene, 1-hexanol, 3Z-hexenyl acetate. Electroantennograms of responses to paired mixtures of odours showed that there was considerable variation in receptor tuning across the receptor field between individuals. Data from some moth antennae showed no additivity, which indicated a restricted receptor profile. Results from other moth antennae to the same odour mixtures showed a range of partial additivity. This indicated that a wider array of receptor types was present in these moths, with a greater percentage of the receptors tuned exclusively to each odour. Peripheral receptor fields show variation in the spectrum of response within a population (of moths) when exposed to high doses of plant volatiles. This may be related to recorded variation in host choice within moth populations as reported by other authors.

Host location behaviour in the desert caterpillar, Heliothis punctifera

The host location behaviour of foraging caterpillars has received little attention, despite the wealth of theoretical and empirical studies that have been directed at this behavioural trait in adult Lepidoptera. Here, we study caterpillars of the moth Heliothis punctifera Walker (Lepidoptera: Noctuidae), which inhabits the arid inland desert areas of Australia. Caterpillars of this species consume many flowerheads before completing development and can be observed moving across the sand in search of new hosts. Consequently, if host location behaviour favours attraction to certain plant species, it might be expected to influence the distribution and abundance of caterpillars in the field. We present field data showing that H. punctifera caterpillars are unevenly distributed throughout mixed patches of two of its host species, with a higher abundance on Senecio gregorii F. Muell., the annual yellow top, compared to Myriocephalus stuartii (F. Muell. & Sond.) Benth., the poached egg daisy (both Asteraceae). Using laboratory studies, we test whether this distribution may, in part, be due to host location behaviour of caterpillars. Our results show that caterpillars exhibit a preference for locating S. gregorii in their pre- and post-contact foraging behaviour. In addition, our results provide evidence that feeding history plays a role in host location behaviour in this insect. We propose that key features of the desert environment and the ecology of H. punctifera would favour adaptations to host location behaviour by immatures.

A comparison of patient matched meibum and tear lipidomes

Purpose. To quantify the molecular lipid composition of patient-matched tear and meibum samples and compare tear and meibum lipid molecular profiles. Methods. Lipids were extracted from tears and meibum by bi-phasic methods using 10:3 tertbutyl methyl ether:methanol, washed with aqueous ammonium acetate, and analyzed by chipbased nanoelectrospray ionization tandem mass spectrometry. Targeted precursor ion and neutral loss scans identified individual molecular lipids and quantification was obtained by comparison to internal standards in each lipid class. Results. Two hundred and thirty-six lipid species were identified and quantified from nine lipid classes comprised of cholesterol esters, wax esters, (O-acyl)-x-hydroxy fatty acids, triacylglycerols, phosphatidylcholine, lysophosphatidylcholine, phosphatidylethanolamine, sphingomyelin, and phosphatidylserine. With the exception of phospholipids, lipid molecular profiles were strikingly similar between tears and meibum. Conclusions. Comparisons between tears and meibum indicate that meibum is likely to supply the majority of lipids in the tear film lipid layer. However, the observed higher mole ratio of phospholipid in tears shows that analysis of meibum alone does not provide a complete understanding of the tear film lipid composition.

The role of biological extracellular matrix scaffolds in vascularized three-dimensional tissue growth in vivo

An in vivo murine vascularized chamber model has been shown to generate spontaneous angiogenesis and new tissue formation. This experiment aimed to assess the effects of common biological scaffolds on tissue growth in this model. Either laminin-1, type I collagen, fibrin glue, hyaluronan, or sea sponge was inserted into silicone chambers containing the epigastric artery and vein, one end was sealed with adipose tissue and the other with bone wax, then incubated subcutaneously. After 2, 4, or 6 weeks, tissue from chambers containing collagen I, fibrin glue, hyaluronan, or no added scaffold (control) had small amounts of vascularized connective tissue. Chambers containing sea sponge had moderate connective tissue growth together with a mild "foreign body" inflammatory response. Chambers containing laminin-1, at a concentration 10-fold lower than its concentration in Matrigel™, resulted in a moderate adipogenic response. In summary, (1) biological hydrogels are resorbed and gradually replaced by vascularized connective tissue; (2) sponge-like matrices with large pores support connective tissue growth within the pores and become encapsulated with granulation tissue; (3) laminin-containing scaffolds facilitate adipogenesis. It is concluded that the nature and chemical composition of the scaffold exerts a significant influence on the amount and type of tissue generated in this in vivo chamber model.

The infectivity and host range of Orgyia anartoides nucleopolyhedrovirus

The painted apple moth (PAM), Teia anartoides (Walker) (Lepidoptera: Lymantriidae) made a recent incursion into New Zealand. A nucleopolyhedrovirus (NPV), Orgyia anartoides NPV (OranNPV), originally isolated from PAM in Australia, was tested for its pathogenicity to PAM and a range of non-target insect species found in New Zealand, to evaluate its suitability as a microbial control for this insect invader. Dosage-mortality tests showed that OranNPV was highly pathogenic to PAM larvae; mean LT50 values for third instars ranged from 17.9 to 8.1 days for doses from 102 to 105 polyhedral inclusion bodies/larva, respectively. The cause of death in infected insects was confirmed as OranNPV. Molecular analysis established that OranNPV can be identified by PCR and restriction digestion, and this process complemented microscopic examination of infected larvae. No lymantriid species occur in New Zealand; however, the virus had no significant effects on species from five other lepidopteran families (Noctuidae, Tortricidae, Geometridae, Nymphalidae and Plutellidae) or on adult honeybees. Thus, all indications from this initial investigation are that OranNPV would be an important tool in the control of PAM in a future incursion of this species into New Zealand.

Resistance or covert infection : baculovirus studies re-examined

Recently, Boots & Begon (1993) described the development of resistance to granulosis virus (GV) (Baculoviridae) infection in the moth Plodia interpunctella, following prolonged exposure to virus in laboratory cultures. Resistant insects exhibited reduced fitness in other respects, namely slower development and reduced egg viability, compared to control insects. These results were interpreted as pleiotropic effects of selection at the loci controlling resistance. Similar results have been described in a previous study: Fuxa & Richter (1989) used artificial selection to increase resistance to nuclear polyhedrasis virus (NPV) (Baculoviridae) infection in the moth Spodoptera frugiperda. The resulting gain in resistance they interpreted as the result of an increase in the frequency of alleles conferring resistance. Again, resistant insects exhibited maladaptive traits compared to controls, including a shorter adult life span, reduced number of eggs and reduced egg viability. In both studies the suggestion is made that selection against maladaptive traits will result in a decline in resistance, once selection for resistance is removed. Boots & Begon (1993) described a decrease in development time (towards that of control insects) within two generations of removing selection for resistance. Fuxa & Richter (1989) describe a decrease in resistance, so that within two generations of relaxing selection, previously resistant lines were not significantly more resistant than control insects. . .

A lucky break : contingency in the storied worlds of prickly pear

In July 1926, the science behind biological control transitioned from an experimental method to a trusted policy tool in invasive species management. In local storytelling, historical writing and scientific analysis, the ‘lucky’ discovery of the South American Cactoblastis cactorum moth was a watershed moment for scientists concerned with prickly pear, Opuntia and Nopalea spp. Within 10 years, Queensland declared itself pest free. Overnight success is the climax in this tale's narrative arc. Articulating this introduction as a ‘lucky break’ worked to stabilize the narrative of human control in the agricultural environments of post-colonial Queensland, and, in doing so, consolidated biological control as critical management technique. I argue that ‘luck’ elides the assemblage of elements and actors necessary to enable this change, allowing settlers to distance themselves from the responsibility for disruptions associated with nineteenth-century plant transfers. To challenge the rhetorical function of luck, three episodes of contingency are discussed: (1) transnational mobility of things and knowledge, (2) the unpredictable adaptation of insect diet, and; (3) human vectors in industrialized insect–plant complexes. There are important distinguishing differences between luck and contingency, which I frame as a critical analytical tool for understanding the political role of non-humans, in the storied worlds of science in prickly pear land.

Identification of the sources of primary organic aerosols at urban schools : a molecular marker approach

Children are particularly susceptible to air pollution and schools are examples of urban microenvironments that can account for a large portion of children’s exposure to airborne particles. Thus this paper aimed to determine the sources of primary airborne particles that children are exposed to at school by analyzing selected organic molecular markers at 11 urban schools in Brisbane, Australia. Positive matrix factorization analysis identified four sources at the schools: vehicle emissions, biomass burning, meat cooking and plant wax emissions accounting for 45%, 29%, 16% and 7%, of the organic carbon respectively. Biomass burning peaked in winter due to prescribed burning of bushland around Brisbane. Overall, the results indicated that both local (traffic) and regional (biomass burning) sources of primary organic aerosols influence the levels of ambient particles that children are exposed at the schools. These results have implications for potential control strategies for mitigating exposure at schools.

Closed Systems

Closed Systems was an exhibition of sculptural works held at MetroArts, Brisbane in the group exhibition 'Platform 2012' curated by Jan Manton. My contribution to the group show was a series of 13 bronze sculptures, produced using a lost-wax casting process. Each form was derived from a sapling that had been manipulated so that branches and roots were interconnected. The resulting 'looped' forms evoked notions on narcissism, self-absorption and introversion. The works were subsequently exhibited at the National Arts School in Sydney as part of the Kodak Minolta Art Prize (2013).

Drying characteristics and quality of grape under physical pretreatment

Grape drying is a slow and energy intensive process because the waxy peel has low permeability to moisture. Therefore, peel chemical and physical pretreatments are considered before drying in order to facilitate water diffusion. However, they cause heterogeneity in the waxes removal and problems during shelf-life. In this paper an alternative abrasive pretreatment of grape peel, for enhancing the drying rate and preserving the samples, was applied to Red Globe grapes. Convective drying experiments were carried out at 40-70 Centigrade and at 2.3 m/s air velocity. The effect of wax abrasive pretreatment on the drying kinetics and quality parameters of raisins was investigated. The results were compared with those of samples pretreated by dipping in alkaline ethyl oleate solution and untreated grapes. All the dried samples are darker than fresh one and shrunked. The samples pretreated by peel abrasion and dried at 50 centigrade showed the lowest color changes, less shrinkage and the best rehydration capacity. The drying kinetics and shrinkage curves were also analyzed using some commonly available empirical models.

15 Artists 2014

15 Artists 2014 was a group exhibition of 2D and 3D works held at the Redcliffe City Art Gallery between October 23 - December 6, 2014. My contribution to the group show was a collective series of 10 soft sculptures entitled Organs Without Bodies. These works were composed of latex, plaster, wool, thread, wax and rosin. I seek through my art practice to transform bodily affect into concrete knowledge. My primary motivation can be described as a relational and ethical attempt to find balance between the erotic and the aggressive. These objects are outcomes from an ongoing creative meditation of the simultaneity of dichotomies: inside and outside, cognition and emotion, past and present, connection and differentiation, the erotic and the aggressive. Each of these can be perceived separately with a penetrating focus of attention, yet all are contained within the 'space' of an expansive bodily-felt sense of awareness.