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1.
J Agric Food Chem ; 60(38): 9562-6, 2012 Sep 26.
Article in English | MEDLINE | ID: mdl-22950817

ABSTRACT

The volatile compounds emitted from uninfested apple seedlings, cv. Royal Gala, and apple seedlings infested with generalist herbivore Epiphyas postvittana larvae were sampled using headspace collection and analyzed by gas chromatography-mass spectrometry. Nine additional compounds were only detected in infested apple seedlings [including benzyl alcohol, (E)-ß-ocimene, benzyl cyanide, indole, (E)-nerolidol, and four unidentified compounds]. Infested apple seedlings produced larger amounts of (Z)-3-hexenyl acetate, linalool, 4,8-dimethyl-1,3(E),7-nonatriene, methyl salicylate, ß-caryophyllene, germacrene D, (E,E)-α-farnesene, and (Z)-3-hexenyl benzoate than uninfested plants. Female parasitoids flew exclusively upwind to infested and not to uninfested apple seedlings in wind tunnel choice tests and preferred infested leaflets in still air, even after the removal of larvae. The attraction of a parasitoid to infested apple seedlings in the laboratory and in the field to apple and many other plants in at least six families supports considerable generality of the tritrophic signaling process.


Subject(s)
Malus/metabolism , Malus/parasitology , Moths/parasitology , Volatile Organic Compounds/analysis , Acetates/analysis , Acyclic Monoterpenes , Alkenes/analysis , Animals , Behavior, Animal , Feeding Behavior , Female , Gas Chromatography-Mass Spectrometry , Hymenoptera , Larva , Monoterpenes/analysis , Odorants/analysis , Seedlings/metabolism , Seedlings/parasitology , Sesquiterpenes/analysis , Trees
2.
J Chem Ecol ; 35(6): 656-63, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19444522

ABSTRACT

This work was undertaken to identify floral compound(s) produced by honeysuckle flowers, Lonicera japonica (Thunberg), that mediate the attraction of New Zealand flower thrips Thrips obscuratus (Crawford). Volatiles were collected during the day and night and analyzed by gas chromatography-mass spectrometry (GC-MS) to determine their emission over these two periods. Nine compounds were identified in the headspace; the main compound was linalool, and the other compounds were germacrene D, E,E-alpha-farnesene, nerolidol, cis-jasmone, cis-3-hexenyl acetate, hexyl acetate, cis-hexenyl tiglate, and indole. There was a quantitative difference between day and night volatiles, with cis-3-hexenyl acetate, hexyl acetate, cis-hexenyl tiglate, and cis-jasmone emitted in higher amounts during the day compared to the night. When the compounds were tested individually in field trapping experiments, only cis-jasmone attracted New Zealand flower thrips in a significant number. In another field trapping experiment, cis-jasmone caught similar numbers of New Zealand flower thrips compared to a floral blend formulated to mimic the ratios of the compounds emitted during the day, while catch with the night-emitted floral blend was not significantly different from the control. Subsequently, two field trapping experiments were conducted to determine the optimal attraction dose for cis-jasmone, a range of 1-100 mg loaded onto a red rubber stopper was tested, and the highest catches were in traps baited with 100 mg loading. A higher range of 100-1000 mg loaded into polyethylene vials was tested, and the highest catch was in traps baited with 500 mg. In another experiment aimed at comparing the attraction efficacy of cis-jasmone with the two other known thrips attractants (ethyl nicotinate and p-anisaldehyde), ethyl nicotinate showed the highest trap catch followed by cis-jasmone. A smaller number of Thrips tabaci (Lindeman) was attracted to traps baited with cis-jasmone. These results suggest that cis-jasmone might act as a kairomone that mediates the attraction of New Zealand flower thrips to the flowers of the Japanese honeysuckle.


Subject(s)
Cyclopentanes/pharmacology , Flowers/chemistry , Lonicera/chemistry , Oxylipins/pharmacology , Animals , Cyclopentanes/chemistry , Cyclopentanes/isolation & purification , Gas Chromatography-Mass Spectrometry , Insect Control/methods , Insecta/physiology , Oxylipins/chemistry , Oxylipins/isolation & purification , Time , Volatile Organic Compounds/chemistry , Volatile Organic Compounds/isolation & purification , Volatile Organic Compounds/pharmacology
3.
J Chem Ecol ; 34(12): 1602-9, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19034574

ABSTRACT

Disruption of Argentine ant trail following and reduced ability to forage (measured by bait location success) was achieved after presentation of an oversupply of trail pheromone, (Z)-9-hexadecenal. Experiments tested single pheromone point sources and dispersion of a formulation in small field plots. Ant walking behavior was recorded and digitized by using video tracking, before and after presentation of trail pheromone. Ants showed changes in three parameters within seconds of treatment: (1) Ants on trails normally showed a unimodal frequency distribution of walking track angles, but this pattern disappeared after presentation of the trail pheromone; (2) ants showed initial high trail integrity on a range of untreated substrates from painted walls to wooden or concrete floors, but this was significantly reduced following presentation of a point source of pheromone; (3) the number of ants in the pheromone-treated area increased over time, as recruitment apparently exceeded departures. To test trail disruption in small outdoor plots, the trail pheromone was formulated with carnuba wax-coated quartz laboratory sand (1 g quartz sand/0.2 g wax/1 mg pheromone). The pheromone formulation, with a half-life of 30 h, was applied by rotary spreader at four rates (0, 2.5, 7.5, and 25 mg pheromone/m(2)) to 1- and 4-m(2) plots in Volcanoes National Park, Hawaii. Ant counts at bait cards in treated plots were significantly reduced compared to controls on the day of treatment, and there was a significant reduction in ant foraging for 2 days. These results show that trail pheromone disruption of Argentine ants is possible, but a much more durable formulation is needed before nest-level impacts can be expected.


Subject(s)
Ants/drug effects , Ants/physiology , Behavior, Animal/drug effects , Pheromones/pharmacology , Aldehydes/pharmacology , Animals , Feeding Behavior/drug effects , Locomotion/drug effects , Walking
4.
J Econ Entomol ; 101(3): 720-7, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18613571

ABSTRACT

The flowers of Canada thistle, Cirsium arvense (L.), attract a wide range of insects, including pollinators and herbivorous species. This attraction is primarily mediated by floral odor, which offers potential for developing generic insect attractants based on odor. In this study, we have analyzed the chemical composition of the volatiles produced by Canada thistle flowers. Nineteen floral compounds were identified in the headspace, including phenylacetaldehyde (55%), methyl salicylate (14%), dimethyl salicylate (8%), pyranoid linalool oxide (4.5%), and benzaldehyde (3.5%). Other minor compounds include benzyl alcohol, methylbenzoate, linalool, phenylethyl alcohol, furanoid linalool oxide, p-anisaldehyde, 2,6-dimethyl-1,3,5,7-octatetraene, benzylacetate, benzyl tiglate, (E,E)-alpha-farnesene, benzyl benzoate, isopropyl myristate, and 2-phenylethyl ester benzoic acid. The relative attractiveness of various doses of the main floral volatile compound phenylacetaldehyde (i.e., 10, 100, 200, and 400 mg) was tested for insect attraction. Both the total catch and the biodiversity of insect species trapped increased as the loading of phenylacetaldehyde increased. Volatiles were chosen from the odors from the flowers of Canada thistle and formulated and tested in the field. An 11-component blend was the most attractive of several floral blends tested. These findings indicate that chemical components of flower odors of Canada thistle can serve as a generic insect attractant for monitoring of invasive pest species.


Subject(s)
Cirsium/parasitology , Flowers/chemistry , Insecta/physiology , Odorants , Pheromones , Animals , Cirsium/chemistry , Insecta/classification , Insecta/pathogenicity , Oils, Volatile/analysis , Species Specificity
5.
J Agric Food Chem ; 53(4): 953-8, 2005 Feb 23.
Article in English | MEDLINE | ID: mdl-15713004

ABSTRACT

The volatile compounds emanating from four fermented sugar baits, palm sugar, golden cane syrup, port wine, and molasses, were isolated by headspace sampling and analyzed by gas chromatography-mass spectrometry. Three classes of compounds including esters, alcohols, and aromatic compounds were identified in the headspace of the four fermented sugar baits. There was a high degree of qualitative similarity between the headspace contents of the four fermented sugar baits, although quantitatively they varied considerably. Ethyl acetate, 3-methylbutanol, ethyl hexanoate, 2-phenylethanol, ethyl octanoate, ethyl (E)-4-decenoate, ethyl decanoate, and ethyl dodecanoate were the major compounds identified in the headspace of the four fermented sugar baits. The efficacy of the four fermented sugar baits was investigated in field trapping experiments. Fermented palm sugar and golden cane syrup were superior in attracting significant numbers of moths as compared to port wine and molasses. Fermented molasses was the least attractive among the four baits. Over 90% of the insects caught were noctuids with Graphania mutans and Tmetolophota spp. being the main noctuids captured (over 55%) in the four fermented sugar baits. Male and female G. mutans were equally attracted to the four sugar baits. A number of tortricid species were also trapped.


Subject(s)
Carbohydrates , Fermentation , Lepidoptera/physiology , Pheromones , Alcohols/analysis , Animals , Esters/analysis , Gas Chromatography-Mass Spectrometry , Moths/physiology , Odorants/analysis , Volatilization
6.
Aust N Z J Ophthalmol ; 22(1): 59-63, 1994 Feb.
Article in English | MEDLINE | ID: mdl-7518686

ABSTRACT

We report three cases of the use of tissue plasminogen activator (TPA) to aid the surgical removal of subretinal haemorrhage. All patients had choroidal neovascular membranes secondary to age-related macular degeneration. The technique involved infusing a sterile solution of TPA through a small retinotomy and irrigating out the dissolved clot. The visual acuity improved in the first patient from a preoperative 6/36 to 6/18 five weeks after surgery, but subsequently deteriorated to 6/60 after six months from a new choroidal neovascular membrane (CNVM), remaining 6/60 at nine months after surgery. The second patient's visual acuity improved from count fingers to 6/24 three weeks after surgery, but subsequently deteriorated to 6/60 after four months from a new CNVM, remaining 6/60 at nine months after surgery. The third patient's visual acuity improved from count fingers to 6/36 and remains stable at 6/36, eight months after surgery. Although long-term prognosis remains guarded, these early results suggest that TPA may have a role in the management of subretinal haemorrhage.


Subject(s)
Retinal Hemorrhage/surgery , Tissue Plasminogen Activator/therapeutic use , Aged , Choroid/blood supply , Combined Modality Therapy , Female , Fundus Oculi , Humans , Macular Degeneration/complications , Male , Neovascularization, Pathologic/etiology , Prognosis , Retinal Hemorrhage/etiology , Retinal Hemorrhage/therapy , Tissue Plasminogen Activator/administration & dosage , Visual Acuity , Vitrectomy
7.
Aust N Z J Ophthalmol ; 14(1): 75-8, 1986 Feb.
Article in English | MEDLINE | ID: mdl-3754452

ABSTRACT

Though vitrectomy results in the general population are being well established, the results in children particularly of amblyopic age are still largely unknown. This paper details the results in 44 children aged one month to 13 years, of whom 28 were seven years of age or less. The most frequent indication for vitrectomy was penetrating ocular trauma (61%). Of the total 44 cases, 28 (63%) were rendered unilaterally aphakic, 18 of these being less than 7 years old. Improvement in vision occurred in 34 (77%) of the 44 patients, and 10 (23%) remained unchanged. In the 18 children aged one month to seven years who became unilaterally aphakic, 11 (61%) improved and seven (39%) remained unchanged. The management of amblyopia and contact lenses in children is stressed. These results indicate that vitreous surgery plays a significant role in the restoration of vision in children.


Subject(s)
Vitrectomy , Adolescent , Amblyopia/surgery , Cataract Extraction , Child , Child, Preschool , Eye Foreign Bodies/surgery , Eye Injuries/surgery , Humans , Infant , Infant, Newborn , Lens, Crystalline/injuries , Lens, Crystalline/surgery , Retinal Diseases/surgery , Retinopathy of Prematurity/surgery , Visual Acuity , Wounds, Penetrating
8.
Aust J Ophthalmol ; 10(2): 135-40, 1982 May.
Article in English | MEDLINE | ID: mdl-6896641

ABSTRACT

Over a four year period three hundred and thirty-nine (339) "at risk" premature neonates were examined, and sixty-five (65) cases of acute R.L.F. (19%) were detected. The overall observed incidence of acute R.L.F. in these surviving babies under 1000 gms birthweight was 47%, in those whose birthweight was 1001-1500 gms the incidence was 22%. The incidence of acute R.L.F., in those babies whose birthweight was greater than 1501-2000 gms was 4.0%. Most of the cases of acute R.L.F. that were detected occurred in those infants with a birth weight less than 1500 gms. Seventy-eight per cent (78%) of these cases of acute R.L.F. were mild and resolved spontaneously. Severe cases occurred only in those babies with a very low birthweight (less than 1100 gms). Active treatment with cryopexy or photocoagulation was undertaken in 15 eyes of 9 infants. Thirteen (13) of the fifteen (15) eyes treated resolved, and there were no blind patients in the series at the end of the study.


Subject(s)
Cryosurgery , Light Coagulation , Retinopathy of Prematurity/surgery , Acute Disease , Birth Weight , Humans , Infant , Infant, Newborn , Infant, Premature , Retinopathy of Prematurity/diagnosis , Retinopathy of Prematurity/epidemiology
9.
Med J Aust ; 1(6): 275-80, 1981 Mar 21.
Article in English | MEDLINE | ID: mdl-7017357

ABSTRACT

The incidence of retrolental fibroplasia (RLF, retinopathy of prematurity) is increasing, as more premature infants of lower birth weight are surviving. Currently, about 17% of premature neonates at risk will develop this condition, although in 85% of these cases it will undergo spontaneous resolution. This paper reviews our current knowledge and management of RLF, and aims to remind us that sophisticated monitoring techniques have not eliminated the problems of hyperoxia.


Subject(s)
Retinopathy of Prematurity , Diagnosis, Differential , Humans , Infant , Infant, Low Birth Weight , Infant, Newborn , Retinopathy of Prematurity/diagnosis , Retinopathy of Prematurity/etiology , Retinopathy of Prematurity/therapy , Risk
11.
Aust J Ophthalmol ; 8(1): 29-33, 1980 Feb.
Article in English | MEDLINE | ID: mdl-7387542

ABSTRACT

Wagner's disease is an uncommon, progressive hereditary vitreoretinal degenerative disease with multiple ocular manifestations, often resulting in severe visual incapacitation in young adults due to formation of cataracts and retinal detachment. The purpose of this paper is to review the clinical features of this disease, and to present a Queensland family with this condition.


Subject(s)
Retinal Degeneration/genetics , Vitreous Body , Adolescent , Adult , Cataract/complications , Diagnosis, Differential , Eye Diseases/genetics , Female , Genes, Dominant , Humans , Male , Pedigree , Refractive Errors/complications , Retinal Degeneration/complications , Retinal Degeneration/physiopathology , Syndrome , Vision, Ocular
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