Responses of the weed parthenium hysterophorus (Asteraceae) to the stem Gall-inducing Weevil Conotrachelus albocinereus (Coleoptera: Curculionidae)
- Authors: Florentine, Singarayer , Westbrooke, Martin , Dhileepan, Kunjithapatham
- Date: 2002
- Type: Text , Journal article
- Relation: Entomologia Generalis Vol. 26, no. 3 (2002), p. 195-206
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- Description: A slem-galling weevil COT/o/rad,e/us alboeinereus Fiedler 1940 from Argentina is being field released to regulate populations of the weed Parlhenium hysterophorus in Queensland, Australia since 1995. In this paper we report the tissue and metabolic responses in P hyslerophorus in the context of the biology and feeding behaviour of the weevil. C albocinereus induces elliptical galls often on the main shoot axes and rarely on the terminal and axillary mcristems of the host plant. From oviposition through gall maturation, the structure and metabolism of the host-plant tissues. especially at the gall region, change continuously to accommodate pressure inflicted by the feeding larva. The host plant shows re-dirtttion of its vital metabolites to the gall, and to the lTlCtaplasitd cells of nutrition in particular. In mature galls. the pith parenchyma elements tum lignified. Larval feeding fractures the vertical continuity of vascular tissues, which affects the host plant's overall metabolism As the larva tunnels the shoot eolulTVl. it places the frass at the fissured vascular sites. That activity initialcs n«rosis and eventual death of the living eells of the vascular tissue complex. Such a development induces water.logging stress in the gall and the evapotranspirauonal system displays contrasting responses. Pennanenl1y closed Siomatal apertures and abnonnally inflated substomatal chambers indicate that P hYSleropltorus suffers moisture-stress with cecidogenesis. The larval performance triggers moisture inundation in the galled shoot and this appears to be an advantage in using this weevil in the control of P hyslerop/rorus.
- Description: C1
- Description: 2003004175
Dietary characteristics of Emus (Dromaius novaehollandiae) in semi-arid New South Wales, Australia, and dispersal and germination of ingested seeds
- Authors: Dunstan, Heath , Florentine, Singarayer , Calvino-Cancela, Maria , Westbrooke, Martin , Palmer, Grant
- Date: 2013
- Type: Text , Journal article
- Relation: Emu Vol. 113, no. 2 (2013), p. 168-176
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- Description: The Emu (Dromaius novaehollandiae) eats a wide range of seeds and other plant material but little is known of the seeds eaten and dispersed in arid Australia. This study aimed to determine the species of seed and fruits eaten by Emus through the year and investigate the effect of the passage of seeds through the Emu gut on seed germination. Emu scats were opportunistically collected in all seasons of 2005 at Nanya Research Station, western New South Wales. Seeds of 29 plant species were retrieved, identified and counted from 221 scats. Seeds of perennial species, such as Belah (Casuarina pauper), Ruby Saltbush (Enchylaena tomentosa), Common Emu-bush (Eremophila glabra) and Nitre-bush (Nitraria billardierei), predominated. Seed composition of scats was more diverse in summer than in winter, autumn and spring. Seeds of Common Emu-bush, Berrigan (Eremophila longifolia) and Sweet Quandong (Santalum acuminatum) showed no germination after passage through the gut. Ruby Saltbush and Nitre-bush showed very low germination rates. The Emu is a generalist feeder, capable of ingesting and dispersing large numbers of plant species. Through high seed consumption and long gut-retention time, Emus could potentially play a significant role in long-distance dispersal of seeds and, through such dispersal, in the vegetation dynamics of arid Australia. © 2013 Bird Life Australia.
- Description: 2003011097
Winter diet of introduced red deer (Cervus elaphus) in woodland vegetation in Grampians National Park, western Victoria
- Authors: Roberts, Cathryn , Westbrooke, Martin , Florentine, Singarayer , Cook, Simon
- Date: 2015
- Type: Text , Journal article
- Relation: Australian Mammalogy Vol. 37, no. 1 (2015), p. 107-112
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- Description: Although red deer (Cervus elaphus) have the potential to play a major role in influencing the structure and composition of vegetation, little is known about the dietary preferences of red deer in Australia. In the Grampians National Park, Victoria, where there is a large, established red deer population, there has been concern over the condition of woodlands, with lack of perennial seedling recruitment observed. We estimated the diets of 12 red deer using macroscopic sorting techniques. We examined rumen contents of seven male and five female red deer from four woodland Ecological Vegetation Classes, which indicate that they act as intermediate feeders. A wide variety of plants were ingested, with evergreen tree species, small trees and woody shrubs making up a large proportion of the diet, along with grasses. This study found that red deer show significantly different dietary intake due to sex, with females consuming a diet much higher in grasses, while males consume more trees and shrubs. These findings have implications for the management of red deer populations within the park and broader implications for their effects on Australian ecosystems.