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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Pursuing quality wine in South Australia : materials, markets, valuations

Brice, Jeremy January 2014 (has links)
This thesis presents an ethnography of the processes and practices through which Australian grape and wine producers attempt to produce, and to assess, quality and value in the materials with which they work. Drawing on participant observation research conducted within two wine companies in South Australia – one owned by a multinational beverage conglomerate, one a family-owned boutique winery – this thesis engages with three overarching questions, which engage with the concerns of agro-food studies and of social studies of markets. First, how – and with what economic effects – are the sensory qualities of materials made to matter within the Australian wine industry? Second, how do grape and wine producers pursue wine quality in a more-than-human world, and in what ways might their endeavours problematise extant theorisations of economic agency? Finally, what might be the consequences of Australian wine producers’ recent engagements with principles of grape and wine quality centred upon geographical origin? In response to these questions, this thesis explores time-reckoning and value production in viticultural practice, the pricing of winegrapes during a fungal disease epidemic, the commercial relationships convened through the production of large-volume mass-market wine blends, and Australian wine producers’ recent attempts to produce ‘wines from somewhere.’ These empirical engagements lead it to argue that the qualification and valuation practices deployed within the Australian wine industry do not simply affect the qualities and prices of grapes and wines. They also shape economic agencies and vulnerabilities, organise and value commercial relationships among grape growers and wine producers, and reassemble the economic geographies of Australian grape production. This thesis concludes that because different ways of pursuing quality enact these phenomena in different ways, much may depend not only upon how successfully, but also upon how – through what techniques, practices, and associations – quality is pursued.
2

Effects of pre-flowering conditions of temperature and light on flower and berry development in model grapevines

Ebadi, Ali. January 1996 (has links) (PDF)
Copies of author's previously published articles inserted. Bibliography: leaves 143-167. Temperature may affect fruit-set in grapevines through its effect on the development of the flowers up to flower opening and on pollination, be it on the germination of the pollen and the growth of the pollen tube, or on the post-fertilisation growth of the ovule.
3

Effects of pre-flowering conditions of temperature and light on flower and berry development in model grapevines / by Ali Ebadi.

Ebadi, Ali January 1996 (has links)
Copies of author's previously published articles inserted. / Bibliography: leaves 143-167. / xvi, 176 leaves, [17] leaves of plates : ill. (chiefly col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Temperature may affect fruit-set in grapevines through its effect on the development of the flowers up to flower opening and on pollination, be it on the germination of the pollen and the growth of the pollen tube, or on the post-fertilisation growth of the ovule. / Thesis (Ph.D.)--University of Adelaide, Dept. of Horticulture, Viticulture and Oenology, 1996
4

The reproductive biology of grapevines: factors that affect flowering and fruitset.

Longbottom, Mardi L. January 2007 (has links)
Molybdenum experiments: In Australia young Merlot vines sometimes suffer from vegetative disorders such as slow, zigzagged growth and leaf distortion. Merlot is also particularly known as a low- and inconsistent-yielding grape variety. Previous research showed that when foliar applications of molybdenum (Mo) were applied to Merlot vines the vegetative symptoms improved. More recently, when sodium molybdate was applied to Mo-deficient Merlot, yield improved; a function of increased bunch weight brought about by bigger berries. It has also been reported that at high concentrations, molybdenum might be detrimental to yield. Experiments were conducted on own-rooted Merlot (clone D3V14) vines in commercial vineyards in the Adelaide Hills (Hills) and at McLaren Vale, South Australia. Effects of molybdenum deficiency on the vegetative growth and yield of Vitis vinifera cv. Merlot: The aims of the current study were to: a) elucidate the mechanism by which molybdenum affects yield of Merlot; b) to monitor the effects of Mo-treatment on the balance between vine reproductive and vegetative growth; c) to monitor the residual effects of Mo-treatment on growth and yield of Merlot and; d) to determine whether high concentrations of molybdenum are detrimental to yield. Three rates of sodium molybdate were applied to vines in springtime (control = 0g, rate 1 = 0.101g and rate 2 = 0.202g sodium molybdate per vine). Vine molybdenum status was measured prior to treatment and again at flowering time using petiole, shoot tip and inflorescence analysis. The effects on vegetative growth were monitored at veraison, during dormancy and at budburst in the seasons following Mo-treatment. At flowering time, pollen vitality, pollen tube growth and flower structure were examined. Bunch number per vine, fruitset, berry weight and berry composition were measured at harvest. In the Hills, the controls had adequate molybdenum however, at McLaren Vale petiolar molybdenum concentration fell within the suggested deficiency range of 0.05-0.09 mg/kg in the petioles at flowering time. No visual symptoms of Mo-deficiency were observed on the experimental vines. At McLaren Vale, Mo-treatment reduced pruning weight and improved vine balance. Mo-treated vines in the Hills and at McLaren Vale were affected by delayed budburst in the season following Mo-treatment irrespective of their Mo-status. However, no seasonal carryover of molybdenum could be detected in tissue analysis at flowering time. Juice total soluble solids, pH and titratable acidity were not affected by Mo-treatment at McLaren Vale or in the Hills. However, juice from Mo-treated vines in the Hills had a significantly higher concentration of molybdenum than the controls. At McLaren Vale there was no significant difference in juice molybdenum concentration between treatments. In the Hills, yield was not affected by Mo-treatment. However, Mo-treated vines at McLaren Vale had significantly higher yields (approximately double) than the Mo-deficient controls. Bunch number per vine was not affected by Mo-treatment, either in the year that treatments were applied or in the following season. However, bunches from Mo-treated vines had significantly better fruitset resulting in more berries per bunch. Berry weight was affected by Mo-treatment in one season only. Yield was not detrimentally affected on vines that received the higher rate of sodium molybdate. In the Hills, Mo-treatment did not affect pollen numbers, pollen vitality or pollen tube growth. At McLaren Vale, where the controls were Mo-deficient, pollen vitality was not affected by Mo-treatment. However, pollen tube growth was significantly enhanced by Mo-treatment. Significantly more pollen tubes penetrated the ovules from Mo-treated vines and a higher proportion of ovaries had at least one penetrated ovule. Structural observations revealed that a significantly higher proportion of ovules from Mo-deficient vines were defective. The absence of an embryo sac in those ovules is probably the cause of pollen tube growth inhibition and subsequent poor fruitset. Effects of mode of pollination on yield of Merlot and the interacting effects of sodium molybdate sprays: Pollination experiments were conducted on field-grown own-rooted Merlot (clone D3V14) vines in commercial vineyards in the Adelaide Hills and at McLaren Vale in 2003-04 and in 2004-05. Inflorescences were supplied with supplementary Merlot pollen (self-pollination), with pollen from another variety (cross-pollination) or they were left to pollinate naturally (open pollination). In the Hills, mode of pollination did not affect fruitset or berry weight. In 2003-04 fruitset increased significantly at McLaren Vale when inflorescences were cross-pollinated with Semillon. Applying supplementary Merlot pollen also tended to improve fruitset, however none of the treatments affected berry weight. In 2004-05 there was no significant difference between treatments. These results indicate that Merlot may be a poor producer of pollen and may suffer from self-incompatibility. Given the significant improvements in yield gained by spring foliar applications of sodium molybdate to Mo-deficient Merlot vines, in 2005-06 a reciprocal experiment was conducted to separate the effects of Mo-treatment and mode of pollination on the male and female flower parts. The aims of this experiment were to: a) determine whether the male or female reproductive organs are more important in determining the success of fruitset of Merlot and; b) determine which remedial measure, Mo-treatment or pollination, is more effective at overcoming poor fruitset. Supplementary pollination treatments—cross-pollination (Semillon); self-pollination (Mo-deficient pollen); self-pollination (Mo-treated pollen) and; open-pollination—were applied to Mo-treated and Mo-deficient vines. Cross-pollinating Mo-deficient vines with Semillon significantly improved fruitset of Merlot compared to other pollination treatments on those vines, however applying molybdenum to the vines in springtime was more effective at improving fruitset. Within the Mo-treated vines the effects of supplementary pollination on fruitset were not thought to be of any practical significance. The results of this experiment provide further evidence that Mo-deficiency affects the female flower parts more than the male reproductive organs of Merlot. The occurrence of ‘star’ flowers in Australia: In 2003 faulty flowers were discovered on Canada Muscat grown in the Coombe Vineyard at the University of Adelaide’s Waite Campus. The Canada Muscat flowers opened from the top in ‘star’ formation in contrast to normal grape flowers, which shed the calyptra from its base. Star flowers were reported in French literature in the late 1800s. They were reported to as a symptom of a ‘disease’ that caused ‘coulure’, the cure for which was vine removal. The current report is the first known report of star flowers occurring in Australia. Through dissemination of the news of this discovery, several star flower variants were found in other varieties in South Australia. The association of star flowers with poor berry development and the frequency of the occurrence of star flowers suggest that this flower aberration may be affecting yield to a greater extent than previously recognised. This study provides a detailed description of two types of star flowers: those that occur in response to environmental conditions and those that occur every season. Other star flower variants are also documented. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1280856 / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2007
5

The reproductive biology of grapevines: factors that affect flowering and fruitset.

Longbottom, Mardi L. January 2007 (has links)
Molybdenum experiments: In Australia young Merlot vines sometimes suffer from vegetative disorders such as slow, zigzagged growth and leaf distortion. Merlot is also particularly known as a low- and inconsistent-yielding grape variety. Previous research showed that when foliar applications of molybdenum (Mo) were applied to Merlot vines the vegetative symptoms improved. More recently, when sodium molybdate was applied to Mo-deficient Merlot, yield improved; a function of increased bunch weight brought about by bigger berries. It has also been reported that at high concentrations, molybdenum might be detrimental to yield. Experiments were conducted on own-rooted Merlot (clone D3V14) vines in commercial vineyards in the Adelaide Hills (Hills) and at McLaren Vale, South Australia. Effects of molybdenum deficiency on the vegetative growth and yield of Vitis vinifera cv. Merlot: The aims of the current study were to: a) elucidate the mechanism by which molybdenum affects yield of Merlot; b) to monitor the effects of Mo-treatment on the balance between vine reproductive and vegetative growth; c) to monitor the residual effects of Mo-treatment on growth and yield of Merlot and; d) to determine whether high concentrations of molybdenum are detrimental to yield. Three rates of sodium molybdate were applied to vines in springtime (control = 0g, rate 1 = 0.101g and rate 2 = 0.202g sodium molybdate per vine). Vine molybdenum status was measured prior to treatment and again at flowering time using petiole, shoot tip and inflorescence analysis. The effects on vegetative growth were monitored at veraison, during dormancy and at budburst in the seasons following Mo-treatment. At flowering time, pollen vitality, pollen tube growth and flower structure were examined. Bunch number per vine, fruitset, berry weight and berry composition were measured at harvest. In the Hills, the controls had adequate molybdenum however, at McLaren Vale petiolar molybdenum concentration fell within the suggested deficiency range of 0.05-0.09 mg/kg in the petioles at flowering time. No visual symptoms of Mo-deficiency were observed on the experimental vines. At McLaren Vale, Mo-treatment reduced pruning weight and improved vine balance. Mo-treated vines in the Hills and at McLaren Vale were affected by delayed budburst in the season following Mo-treatment irrespective of their Mo-status. However, no seasonal carryover of molybdenum could be detected in tissue analysis at flowering time. Juice total soluble solids, pH and titratable acidity were not affected by Mo-treatment at McLaren Vale or in the Hills. However, juice from Mo-treated vines in the Hills had a significantly higher concentration of molybdenum than the controls. At McLaren Vale there was no significant difference in juice molybdenum concentration between treatments. In the Hills, yield was not affected by Mo-treatment. However, Mo-treated vines at McLaren Vale had significantly higher yields (approximately double) than the Mo-deficient controls. Bunch number per vine was not affected by Mo-treatment, either in the year that treatments were applied or in the following season. However, bunches from Mo-treated vines had significantly better fruitset resulting in more berries per bunch. Berry weight was affected by Mo-treatment in one season only. Yield was not detrimentally affected on vines that received the higher rate of sodium molybdate. In the Hills, Mo-treatment did not affect pollen numbers, pollen vitality or pollen tube growth. At McLaren Vale, where the controls were Mo-deficient, pollen vitality was not affected by Mo-treatment. However, pollen tube growth was significantly enhanced by Mo-treatment. Significantly more pollen tubes penetrated the ovules from Mo-treated vines and a higher proportion of ovaries had at least one penetrated ovule. Structural observations revealed that a significantly higher proportion of ovules from Mo-deficient vines were defective. The absence of an embryo sac in those ovules is probably the cause of pollen tube growth inhibition and subsequent poor fruitset. Effects of mode of pollination on yield of Merlot and the interacting effects of sodium molybdate sprays: Pollination experiments were conducted on field-grown own-rooted Merlot (clone D3V14) vines in commercial vineyards in the Adelaide Hills and at McLaren Vale in 2003-04 and in 2004-05. Inflorescences were supplied with supplementary Merlot pollen (self-pollination), with pollen from another variety (cross-pollination) or they were left to pollinate naturally (open pollination). In the Hills, mode of pollination did not affect fruitset or berry weight. In 2003-04 fruitset increased significantly at McLaren Vale when inflorescences were cross-pollinated with Semillon. Applying supplementary Merlot pollen also tended to improve fruitset, however none of the treatments affected berry weight. In 2004-05 there was no significant difference between treatments. These results indicate that Merlot may be a poor producer of pollen and may suffer from self-incompatibility. Given the significant improvements in yield gained by spring foliar applications of sodium molybdate to Mo-deficient Merlot vines, in 2005-06 a reciprocal experiment was conducted to separate the effects of Mo-treatment and mode of pollination on the male and female flower parts. The aims of this experiment were to: a) determine whether the male or female reproductive organs are more important in determining the success of fruitset of Merlot and; b) determine which remedial measure, Mo-treatment or pollination, is more effective at overcoming poor fruitset. Supplementary pollination treatments—cross-pollination (Semillon); self-pollination (Mo-deficient pollen); self-pollination (Mo-treated pollen) and; open-pollination—were applied to Mo-treated and Mo-deficient vines. Cross-pollinating Mo-deficient vines with Semillon significantly improved fruitset of Merlot compared to other pollination treatments on those vines, however applying molybdenum to the vines in springtime was more effective at improving fruitset. Within the Mo-treated vines the effects of supplementary pollination on fruitset were not thought to be of any practical significance. The results of this experiment provide further evidence that Mo-deficiency affects the female flower parts more than the male reproductive organs of Merlot. The occurrence of ‘star’ flowers in Australia: In 2003 faulty flowers were discovered on Canada Muscat grown in the Coombe Vineyard at the University of Adelaide’s Waite Campus. The Canada Muscat flowers opened from the top in ‘star’ formation in contrast to normal grape flowers, which shed the calyptra from its base. Star flowers were reported in French literature in the late 1800s. They were reported to as a symptom of a ‘disease’ that caused ‘coulure’, the cure for which was vine removal. The current report is the first known report of star flowers occurring in Australia. Through dissemination of the news of this discovery, several star flower variants were found in other varieties in South Australia. The association of star flowers with poor berry development and the frequency of the occurrence of star flowers suggest that this flower aberration may be affecting yield to a greater extent than previously recognised. This study provides a detailed description of two types of star flowers: those that occur in response to environmental conditions and those that occur every season. Other star flower variants are also documented. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1280856 / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2007

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