School of Agriculture, Food and Wine
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The School of Agriculture, Food & Wine provides a world-class concentration of scientific research, education and infrastructure on the Waite Campus with a smaller presence on the Roseworthy Campus. Research interests within the School include plant sciences, plant biotechnology, plant breeding, agronomy, soil science, integrated pest management, horticulture, viticulture, oenology, wine business, food science, and agricultural & resource economics.
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Item Metadata only The feeding behaviour of caterpillars (Manduca sexta) on tobacco and on artificial diet(Wiley, 1986) Reynolds, S.; Yeomans, M.; Timmins, W.Feeding behaviour of fifth instar tobacco hornworm caterpillars, Manduca sexta (Johansen) (Lepidoptera; Sphingidae), eating tobacco or artificial diet, is quantitatively described. The insects grow at the same rate on both foods. There is no daily rhythm of feeding behaviour. For most insects, feeding on either food occurs in bouts with the lengths of interfeed gaps and of feeding bouts appearing to be distributed randomly. However, in many insects there is a strong correlation between the length of a feeding period and that of the preceding non-feeding period. The proportion of time spent feeding on tobacco is much greater than on artificial diet. On tobacco, feeding periods are separated by shorter interfeed gaps than on the artificial diet, while the rate of bout initiation is similar on either food. On both tobacco and artificial diet, the proportion of time spent feeding increases as the fifth stadium proceeds. This is due to both longer feeding bouts and shorter gaps. The rate of food acquisition within bouts does not change during the stadium.Item Metadata only Beneficial arthropod behavior mediated by airborne semiochemicals. I. Flight behavior and influence of preflight handling of Microplitis croceipes (Cresson)(Plenum Publishers, 1986) Drost, Y.C.; Lewis, W.J.; Zanen, P.O.; Keller, M.A.Oriented responses of Microplitis croceipes (Cresson) to airborne odors of actively feedingHeliothis zea (Boddie) larvae were observed in a flight tunnel. The behavior of M. croceipes prior to and during sustained, oriented flights was videotaped and analyzed in detail. Preflight exposure of the parasitoid to feces and other components of the plant-host complex were found to be vital in effective flight behavior, while maturation of the parasitoid had little effect. The increased frequency of oriented flight that resulted from preflight exposure of a plant-host complex persisted for at least 24 hr.Item Metadata only A convenient synthesis of 5-alkylbicyclo[3.1.0]hexan-2-ones including the natural product sabina ketone(CSIRO Publishing, 1987) Hamon, D.P.; Shirley, N.J.Simple 5-alkylbicyclo[3.1.0]hexan-2-ones, including the natural product sabina ketone, can be prepared in four steps from aromatic ethers via Birch reduction, hydrogen chloride addition, hydrolysis and then base treatment of the resultant 4-chlorocyclohexanones.Item Metadata only Influence of leaf surfaces on movements by the hymenopterous parasitoid Trichogramma exiguum(Wiley, 1987) Keller, M.A.Walking speeds of female Trichogramma exiguum Pinto & Platner were fastest on maize and soybean (12 cm/min), intermediate on tomato (8 cm/min), and slowest on woolly mullein, Verbascum thapsus (3 cm/min). Similarly, rates of turning along the paths of walking T. exiguum were smallest on maize (median angle = 0° ± 15°), intermediate on soybean and tomato, and greatest on V. thapsus (median angle = 30° ± 15°). Leaf trichome density and morphology influenced walking behavior. Walking was slowed and flight initiation delayed for T. exiguum walking on Amaranthus hybridus leaves compared to either maize or filter paper. When inundative releases are conducted, the effects of plant surfaces on searching rates and arrestment should be considered in determining release rates of Trichogramma spp. = Les vitesses de marche, les taux de changement de direction et les taux d'envol sur divers substrats végétaux chez Trichogramma exiguum. La vitesse de marche a été déterminée en lâchant des individus sur chaque substrat végétal et en traçant leur parcours sur une plaque de verre placée à 9 mm au dessus du sujet. Les déviations angulaires de portions successives des tracés, longues de 1 mm, ont été utilisées pour mesurer les taux de changement de direction. Dans une deuxième expérience, des individus ont été lâchés au milieu d'une cercle de 40 mm de diamètre sur chaque substrat et les temps écoulés avant I'envol ou pour atteindre le bord du cercle à la marche ont servi à évaluer respectivement la propension au vol et la vitesse de déambulation. Les vitesses de marche ont été les plus rapides sur maïs et soja (12 cm/min), moyennes sur tomate (8 cm/min) et les plus lentes sur Verbascum thapsus (Scrophulariaceae) (3 cm/min). De le même façon, les angles de changement de direction au cours des marches effectuées par T. exiguum ont été plus petits sur maïs, moyens sur soja et tomate, et plus grands sur V. thapsus. Chez T. exiguum marchant sur des feuilles d'Amaranthus hybridus L. (Amaranthaceae), la marche a été plus lente et l'envol plus tardif que sur maīs ou papier filtre. Lors de lâchers inondatifs, les effets des surfaces végétales sur les vitesses d'exploration et d'arrêt devraient être pris en compte pour déterminer les vitesses de lâcher des Trichogramma spp.Item Metadata only Food intake, conversion efficiency, and feeding behaviour of tobacco hornworm caterpillars given artificial diet of varying nutrient and water content(Wiley, 1988) Timmins, W.; Bellward, K.; Stamp, A.; Reynolds, S.Fifth stadium tobacco hornworm caterpillars, Manduca sexta (L.), given artificial diet diluted to varying extents with either cellulose or water compensated for the food's reduced nutrient content by eating more of it. This compensation was, however, in most cases not sufficient to maintain normal growth rates. When the water content of the diet was reduced, the insects ate less than the usual fresh weight of food but maintained their intake of nutrients. Nevertheless, growth rate was impaired. The insects were better able to compensate for dilution of their food with water than with cellulose. The efficiency of conversion of ingested food (ECI) was decreased when the diet was adulterated with cellulose. At moderate dilution (50% nutrient) this was due mostly to decreased approximate digestibility (AD), but at greater dilution (25% and 10% nutrient content) the efficiency of conversion of digested food (ECD) was decreased. ECI was maintained when the water content of the diet was increased to give 50% nutrient concentration, but was decreased when water content was changed more radically (200%, 25% and 10% nutrient diets). This was due mostly to increased metabolic costs (decreased ECD) in all cases. The retention time of food in the gut was progressively decreased (i.e. speed of passage was increased) as nutrients were replaced by cellulose. By contrast, dilution of the diet with water resulted in only slight changes in retention time, except at extreme dilution (10% nutrient content) when retention time was reduced. Compensation of food intake was achieved by spending more (or less) time eating. Video analysis of feeding behaviour showed that there were significant changes in the length of feeding bouts and of interfeed gaps when caterpillars fed on diets of altered composition. For diets diluted with cellulose, changes in bout length and bout frequency contributed substantially to the increased time spent feeding on the adulterated food. For diets diluted with water, however, almost all of the compensatory change in behaviour was due to increased bout length, with bout frequency affected only slightly. This suggests that volumetric feedback contributes principally to the termination of feeding bouts in caterpillars, while nutrient flow may affect both the initiation and termination of feeding.Item Metadata only Beneficial arthropod behavior mediated by airborne semiochemicals. III. Influence of age and experience on flight chamber responses of Microplitis demolitor Wilkinson(Plenum Publishers, 1988) Herard, F.; Keller, M.A.; Lewis, W.J.; Tumlinson, J.H.Heliothis zea (Boddie) larvae fed cowpea seedlings produced volatile semiochemicals to which Microplitis demolitor Wilkinson responded in a wind tunnel. However, most M. demolitor females reared from H. zea larvae fed an artificial diet were not responsive at emergence to the same volatile semiochemicals. A preflight contact with frass from H. zea fed cowpea was needed to stimulate a response of sustained flight in a wind tunnel. The most consistent flight response was 7-10 days postemergence. Response resulting from both antennal and ovipositor contact with host frass during preflight stimulation was no better than from antennal contact alone. Chilling the parasitoid pupae rendered most of the emerging females unresponsive to volatile semiochemicals.Item Metadata only An asymmetric intramolecular alkylation to form a bicyclo[3.1.O]hexanone derivative(Royal Society of Chemistry, 1988) Hamon, D.P.; Shirley, N.J.The epoxy ketol (–)-2-hydroxymethyl-1-oxaspiro[2.5]octan-6-one (7b) isomerises with base to 1-(1,2-dihydroxy-1-methylethyl)bicyclo[3.1.0]hexan-4-one (5b) with high diastereoselectivity.Item Metadata only Beneficial arthropod behavior mediated by airborne semiochemicals. IV. Influence of host diet on host-oriented flight chamber responses of Microplitis demolitor Wilkinson(Plenum Publishers, 1988) Herard, F.; Keller, M.A.; Lewis, W.J.; Tumlinson, J.H.Microplitis demolitor Wilkinson were reared from Heliothis zea larvae fed either an artificial diet or a diet of cowpea seedlings. Responses of females from these two sources to semiochemicals from the insect host cowpea complex were compared in a flight tunnel. Very limited responses were obtained from females reared from hosts fed artificial diet unless they first had preflight contact with frass from plant-fed hosts. Female parasite is reared from plant-fed hosts were generally responsive without preflight contact. Contact with cocoons containing frass of the plant fed host at the time of emergence was an important source of stimulation. It increased their subsequent responsiveness to the volatile semiochemicals of the insect host-plant complex. The cocoons of females reared from artificial diet-fed hosts were apparently lacking plant chemicals that are vital to their subsequent responsiveness. Imprinting of the adults at time of emergence from the cocoon is strongly indicated.Item Metadata only Correlations between grain-yield and percentage grain moisture at harvest in ontario hybrid corn trials(Agricultural Institute of Canada, 1989) Mather, D.E.; Kannenberg, L.W.The correlation between hybrid corn (Zea mays L.) grain yield and percentage grain moisture at harvest was measured in Ontario performance trial data. Positive correlations were detected in mid- to full-season areas.Item Metadata only Opportunities for improvement in sheep and beef cattle production in the south east of South Australia(ASAP, 1990) Trengove, C.L.; 18th Biennial Conference of the Australian Society of Animal Production (Jul 1990 : Adelaide, South Australia); Judson, G.J.A random sample of 300 farms in the South East of South Australia was surveyed to determine current management practices and to identify areas where farm profitability could be improved. Eighty one percent of sheep flocks lambed during February - May, and 81% joined ewes for more than 8 weeks. Lambs were weaned more than 14 weeks after lambing in 62% of Merino flocks and more than 17 weeks after lambing in 43% of other breed flocks. No flocks were considered to have adequate worm control. Nearly all beef herds calved during January - May and 78% joined heifers and 83% joined cows for 12 weeks or longer. Less than 25% of herds monitored growth rates or pregnancy status. In most cattle herds worm drenching was excessive in adults and inefficient in yearlings. A conclusion from the survey is that reproductive management and worm control practices of both sheep and cattle can be improved in most flocks and herds. Altering management to a shorter joining, later lambing and earlier weaning in sheep would improve the efficiency of sheep production. For cattle, shorter mating periods for cows and heifers, earlier age of joining for heifers, and the joining of heifers 3-4 weeks earlier than cows would be widely beneficial.Item Metadata only Major gene control of tolerance of bread wheat (Triticum aestivum L.) to high concentrations of soil boron(Kluwer Academic Publishers, 1991) Paull, J.G.; Rathjen, A.J.; Cartwright, B.The genetic control of tolerance of wheat to high concentrations of soil boron was studied for five genotypes. Each genotype represented one of five categories of response to high levels of boron, ranging from very sensitive to tolerant. Tolerance to boron was expressed as a partially dominant character, although the response of an F1 hybrid, relative to the parents, varied with the level of boron applied. The F1 hybrids responded similarly to the more tolerant parent at low B treatments and intermediate to the parents at higher treatments. Ratios consistent with monogenic segregation were observed for the F2 and F3 generations for the combinations (WI*MMC) × Kenya Farmer, Warigal × (WI*MMC) and Halberd × Warigal. The three genes, Bo1, Bo2 and Bo3, while transgressive segregation between two tolerant genotypes, G61450 and Halberd, suggested a fourth locus controlling tolerance to boron.Item Metadata only ¹³C Chemical shifts and ¹³C-¹⁵N coupling constants of some ¹⁵N‐labelled bridgehead nitro compounds(Wiley, 1992) Della, E.W.; Janowski, W.K.; Kasum, B.; Kirkbride, P.K.; Shirley, N.J.Measurement of the ¹³C NMR spectra of the bridgehead nitro compounds 1a–5a has been performed. It is found that one‐bond ¹³C-¹⁵N coupling is not necessarily a reflection of the degree of s character of the bridgehead carbon exocyclic bonding orbital. Although the magnitude of vicinal coupling to the bridgehead carbon increases, in accordance with the number of three‐bond pathways available for transmission of spin information, coupling is actually reduced by opposing contributions from through‐space intramolecular orbital interactions.Item Metadata only Physiological mechanisms underlying the control of meal size in Manduca sexta larvae(Wiley, 1992) Timmins, W.; Reynolds, S.Fifth stadium larvae of the tobacco hornworm, Manduca sexta (L.), ate larger meals than usual when they had been deprived of food for periods of time longer than the usual intermeal interval (c. 45 min). Meal size increased with time since the last meal until 180 min, when it was about 3 times normal. There was no evidence of a role for volumetric feedback from the gut in controlling meal size. Injections of a paraffin oil/wax mixture, or of petroleum jelly (Vaseline) into the foregut, midgut or rectum failed to decrease meal size. Cutting the recurrent nerve failed to alter meal size compared to sham-operated controls (although both groups took smaller meals than unoperated controls). By contrast, injections of an extract of soluble nutrients from the diet into the midgut inhibited feeding in some insects and reduced subsequent meal size in others. Appropriate controls showed that these effects were not due to the volumetric or osmotic effects of the injections. These results imply that nutrient feedback plays an important role in controlling meal size in Manduca caterpillars, while volumetric feedback is probably unimportant.Item Metadata only Enhanced fetal growth in sheep administered progesterone during the first three days of pregnancy(Blackwell Scientific Publications, 1994) Kleeman, D.; Walker, S.; Seamark, R.Two experiments were conducted to determine whether administration of progesterone during early pregnancy affects fetal growth in sheep and if any effect is specific to the days of treatment. In the first experiment, Merino ewes were randomly allocated to four treatment groups and inseminated at a synchronized oestrus. Three groups received progesterone on days 1-3, 3-6 or 1-6 of pregnancy while the fourth group was untreated. Concentrations of progesterone in peripheral plasma increased (P < 0.05) in all treatment groups. Fetal growth (to day 74) was greater in all treatment groups than in the control group (P < 0.001) and was greatest when treatments started on day 1. Pregnancy rate was not affected by progesterone treatment on days 3-6, but was reduced (P < 0.05) when treatment began on day 1. In the second experiment, embryos that had been exposed to either a normal (control) or a high concentration of progesterone on days 1-3 were randomly transferred, within groups, to recipient ewes that had or had not been treated with progesterone on days 1-3. In another group, embryos were exposed to a high concentration of progesterone on days 1-3 and the oviducts of the ewe were ligated. An increase in fetal mass was observed in the recipient group that had been treated with progesterone (P < 0.01) but was not observed in the initial group treated with progesterone. A greater fetal mass was also obtained when embryos that had been ligated in the oviducts of ewes treated with progesterone (P < 0.05) were transferred.(ABSTRACT TRUNCATED AT 250 WORDS)Item Metadata only Response of juvenile Melaleuca halmaturorum to flooding: Management implications for a seasonal wetland, Bool Lagoon, South Australia(CSIRO, 1994) Denton, M.; Ganf, G.G.The response of M. halmaturorum was measured to determine the ability of juvenile plants to survive flooding and to examine how this influenced plant growth. Seedlings and one- and two-year-old plants were flooded to 0% (control), 50% or 100% of their initial height for periods of three to 14 weeks, followed by an eight-week recovery period. Only 22% of seedlings survived five weeks of 100% coverage, but these died during the recovery period. The older plants survived the flooding treatments well, but as duration increased so survival through the recovery period declined. After 100% coverage for six weeks followed by the recovery period, only 29% survived. Stem linear extension rates corresponding to these survival rates were used to predict the survival of juvenile M. halmaturorum in Bool Lagoon, South Australia. The results showed that, with the current water regime, natural recruitment would occur only at the highest elevation but that this could be improved by planting older, taller plants at lower elevations. Indices of growth showed that flooded plants performed poorly compared with the controls as duration and percentage of coverage increased. The data suggested that coverage inhibited plant growth during the flood period, but there was a further, interactive response to duration that became apparent after the post-flood recovery period. An interpretation of these results is that M. halmaturorum in its juvenile stages is intermediate between a flood-sensitive and a flood-tolerant species because it is able to recover from short floods of three weeks or less but performs poorly if floods exceed six to nine weeks.Item Metadata only Occurrence of anthocyanin pigments in berries of the white cultivar Muscat Gordo Blanco (Vitis vinifera L.)(Australian Society of Viticulture & Oenology, 1995) Gholami, Mansour; Coombe, B. G.Rose coloration of skin was observed to sometimes develop late during ripening on the normally white grape berries of cv. Muscat Gordo Blanco. The nature of the pigment was investigated by HPLC analysis of skin extracts of single berries. The predominant anthocyanin was identified as cyanidin-3-glucoside with minor amounts of delphinidin- and peonidin-3-glucosides. This composition resembles the skin composition of coloured, small-seeded muscat cultivars which it also resembles by the monoterpene composition of the juice. The pigments occurred only in berries with levels of total soluble solids in excess of 24°Brix in the juice and such berries tended to have smaller fresh weight. Berry pigmentation occurred on vines with various root systems. The specific conditions under which pigment developed in Muscat Gordo berries may offer a useful tool in the study of anthocyanin biosynthesis.Item Metadata only In vivo growth of a murine lymphoma cell line alters regulation of expression of Hsp72(American Society for Microbiology, 1995) Davidson, Sean; Hoj, Peter Bordier; Gabriele, Tim; Anderson, Robin L.We have identified a murine B-cell lymphoma cell line, CH1, that has a much-diminished capacity to express increased levels of heat shock proteins in response to heat stress in vitro. In particular, these cells cannot synthesize the inducible 72-kDa heat shock protein (HSP72) which is normally expressed at high levels in stressed cells. We show here that CH1 fails to transcribe HSP72 mRNA after heat shock, even though the heat shock transcription factor, HSF, is activated correctly. After heat shock, HSF from CH1 is found in the nucleus and is phosphorylated, trimerized, and capable of binding the heat shock element. We propose that additional signals which CH1 cells are unable to transduce are normally required to activate hsp72 transcription in vitro. Surprisingly, we have found that when the CH1 cells are heated in situ in a mouse, they show normal expression of HSP72 mRNA and protein. Therefore, CH1 cells have a functional hsp72 gene which can be transcribed and translated when the cells are in an appropriate environment. A diffusible factor present in ascites fluid is capable of restoring normal HSP72 induction in CH1 cells. We conclude that as-yet- undefined factors are required for regulation of the hsp72 gene or, alternatively, that heat shock in vivo causes activation of hsp70 through a novel pathway which the defect in CH1 has exposed and which is distinct from that operating in vitro. This unique system offers an opportunity to study a physiologically relevant pathway of heat shock induction and to biochemically define effectors involved in the mammalian stress response.Item Metadata only FKBP39, a Drosophila member of a family of proteins that bind the immunosuppressive drug FK506(Elsevier, 1995) Theopold, Ulrich; Dal Zotto, Laura; Hultmark, Dan; School of Agriculture, Food and Wine : Plant and Food ScienceItem Metadata only Molecular evolution of plant β-glucan endohydrolases(Blackwell Scientific Publishers, 1995) Hoj, Peter Bordier; Fincher, Geoffrey B.