Percentage in-vitro conidial germination of inaequalis was inversely related to the log conidial concentration. The filtrate from a conidial suspension of inaequalis was shown to inhibit conidial germination. Ferrous iron was shown to reduce conidial germination. Anthranillic acid reversed the inhibitory action of ferrous iron and enhanced germination of conidial suspensions not containing additional iron. Continuous rolling or ''pre-treatment" of conidial suspensions of V. inaequalis used for inoculum increased levels of infection. It was suggested that this improvement may be a result of higher numbers of germinated conidia present on the leaf surface. Pre-treatment of inocula was adopted as a standard inoculation technique. Symptom expression was studied under two categories :- i) Effect on seedling growth (stunting/promotion) ii) Foliar symptoms (total disease expression score - TDE) Stunting and TDE values were correlated to lesion number and positively correlated to inoculum concentration. High inoculum concentrations caused stunting and low ones resulted in growth promotion. Similar responses were found with all apple varieties tested. Experimental evidence was presented to support the hypotheses :- 1) Conidia only produce stunting. 2) The filtrate from a pre-treated conidial suspension of V. inaequalis contained a factor which induced growth promotion of apple seedlings. Washing pre-treated conidia with GDW immediately before inoculation enhanced stunting of apple seedlings. Foliar sprays of the pre-treatment filtrate promoted seedling growth, concentrating it further enhanced promotion. The factor responsible was resistant to boiling, suggesting it to be non-protein but after standing for 24 h lost its ability to promote growth. Bioassays of the filtrate for IAA and cytokinins were negative. A dock leaf disk test was positive for gibberellins. Analysis of the filtrate using mass spectrometry indicated the presence of high molecular weight ions but it was not possible to identify any particular fragment or conclude whether these could be responsible for growth enhancement. It is suggested that the filtrate acts by increasing cell elongation rather than cellular proliferation. Use of the fungicides dodine and captan produced a host response to infections by inaequalis ranging from stunting to growth promotion. The potential of pre-treatment and symptom assessment for use as a fungicide screening technique was demonstrated. It was suggested that summation of the ranked scores for TDE and phytotoxic stunting provided an accurate assessment of a chemical's suitability for further testing.

The British Columbia Apple industry, primarily located in the Southern Interior of the province, has undergone varying levels of tree removal and replanting as growers attempt to maximize profits. This study models their behaviour by using econometrics in a supply response model. The economic environment of the fruit industry is described. The variables affecting acreage responses to removals and replanting of new and traditional apple varieties are estimated using Ordinary Leased Squares in three separate equations. Data are pooled and aggregated at the regional level. Several versions of the original model are run to test for robustness of the variables and of the original model. The econometric models illustrated that the plantings of new varieties increases when expected profits from vintage trees decline. However, planting and removals of traditional varieties are positively related to excepted profits from vintage trees and this does not follow apriori expectations. More striking in the model is the regional differences and their responsiveness to removals and replanting. Regions with younger, better educated farmers replant to new varieties at a faster rate than other regions. Replant programs are shown to have a negative effect on the rate of replanting. These programs maintain basic criteria for their eligibility to funding and seemingly decreased the acres replanted. Increasing the monetary value of the replant grants results in the effect of increasing the acreage of traditional varieties being planted. Policy implications are examined in a post modelling analysis. The effects of top loading subsidy effects are shown to have decreased the acreage of trees replanted over time. These effects are shown to cause a dead weight loss to society of approximately $13 million over 20 years. / Land and Food Systems, Faculty of / Graduate

In order to prevent enzymatic oxidation of phenols during the centrifugal extraction of juice from apple purée, a sulfite or ascorbic acid treatment followed by blanching has been proposed. However, juice from blanched puree is more turbid and difficult to clarify than juice processed without blanching. In order to better understand the effect of blanching on juice turbidity as well as to provide more information concerning the effect of cultivar, post-harvest storage and enzyme treatment on juice quality, the chemical and physical properties of apple juice and apple juice particulate from fresh and stored McIntosh, Red Delicious and Spartan apples processed with and without enzyme digestion and with and without blanching were examined. Analysis of juice included measurement of: soluble solids, total sugars (by HPLC), sucrose, glucose, fructose, sorbitol, pH, titratable acidity, total acidity (by HPLC), citric acid, galacturonic acid, malic acid, quinic acid, succinic acid, pectin (as anhydrogalacturonic acid by HPLC) and turbidity (as absorbance at 600 nm). Analysis of particulate included measurement of dry matter weight, pectin, protein and zeta potential as well as thin sectioning, negative staining and shadow casting transmission electron microscopy. Chemical analysis of apple juice showed that the levels of organic acids, sugars and soluble pectin differed between cultivars. However, no varietal differences were observed in the chemical or microscopic analysis of cloud material. Blanching of apple puree, on the other hand, increased apple juice turbidity by increasing the amount of particulate suspended in the juice. Furthermore, blanching stabilized suspended particulate by what appeared to be the formation of a protective colloid which prevented particle aggregation through electrostatic repulsion. Post-harvest apple storage also resulted in changes to juice particulate, which were observed as gel formation during juice storage at 0°C and as a web-like aspect in the microscopic appearance of juice particulate. Treatment of apple purée with Ir-gazyme 100 decreased juice turbidity, resulting in the concomitant decrease in both the level of soluble juice pectin and the amount of suspended cloud material. Use of enzyme treatment and blanching in the processing of apple juice was demonstrated by stepwise discriminant analysis to allow production of four unique apple juice products. / Land and Food Systems, Faculty of / Graduate

My Diploma Thesis is aimed to clarify the position of the Apple Incorporated in the world economy, as well as expectations and anticipations for future. I decided to write about Apple not only because it's one of the leading company in the technology Market, but because interest to its production is increasing day by day, making it highly competitive. Coming to the content of my work: It consists of 3 chapters, with several subchapters being included into each chapter. The first chapter is an overview of the company's history, showing step by step its growth, rise and fall periods, first computers and production. As all the history of Apple existence is connected with the name of Steve Jobs, I decided to express my opinion about Post-Steve Jobs era. Second chapter consists of PEST,SWOT,Competitor and product analysis of the company's product, where iPhone, Ipad and Mac were analyzed. and the third and last chapter reveals vision and mission of the company,its preferences, values, finishing with very positive note, such as the short overview of the most successful products of the company.

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The life history of the aphidophagous syrphid fly, Heringia calcarata (Loew), a specialist predator of woolly apple aphid, Eriosoma lanigerum (Hausmann), was studied in Virginia from 2001 to 2003, under field and laboratory conditions. Pronounced differences in the chorionic sculpting of eggs of Eupeodes americanus (Wiedemann), Syrphus rectus Osten Sacken, and H. calcarata were documented. These differences can be used to separate these aphidophagous hover flies. Gross morphological descriptions of all life stages of H. calcarata were reported and the duration of the developmental period of all life stages was quantified. The phenology and relative abundance of H. calcarata was studied in the field using water pan traps, sticky traps, emergence traps, sentinel trees, and destructive sampling of aphid colonies. Sentinel trees with woolly apple aphid colonies were most effective for phenological studies, and showed that female H. calcarata were present in apple orchards from April through September. Emergence traps revealed that H. calcarata adults emerge from the duff or soil beneath apple trees. Prey specialization of H. calcarata on woolly apple aphid was studied using no-choice and choice feeding bioassays and oviposition patterns in the field. Feeding studies compared the consumption of three, temporally sympatric aphid pests of apple: spirea aphid, Aphis spiraecola Patch, rosy apple aphid, Dysaphis plantaginea (Passerini), and woolly apple aphid. Compared with spirea aphid or rosy apple aphid, a pure diet of woolly apple aphid resulted in significantly higher larval survivorship and weight, and a significantly shorter developmental period. Naïve, neonate larvae exhibited a marked preference for woolly apple aphid. Weekly counts of hatched and unhatched syrphid eggs revealed that H. calcarata was present only in woolly apple aphid colonies, where it was the most abundant hover fly species. Our data indicate that H. calcarata is a specialist predator of the woolly apple aphid in the apple ecosystem in Virginia. / Master of Science

High pressure (HP) processing, a novel technology, has excellent potential for non-thermal preservation of apple juice, the largest consumed fruit juice in North America. The objective of this research was to evaluate the application of HP treatment for inactivation of enzymes and destruction of microorganisms in apple juice. HP inactivation kinetics of selected enzymes (amylase, pectin methyl esterase and polyphenol oxidase) and microorganisms [Leuconostoc mesenteroides, Pichia membranaefaciens and Zygosaccharomyces badii, Escherichia coli (29055) and Escherichia coli (O157:H7)] in apple juice were evaluated under various test conditions (100--400 MPa, 0--60 min and 6--40°C) using a central composite design of experiments. The enzymes selected were of importance in apple juice preparation and/or storage stability of the processed juice. Microorganisms included those that are responsible for spoilage and/or public health concern as well as those that are indicative of unsanitary handling conditions. / Enzyme inactivation and microbial destruction due to pressure followed a dual-effect model consisting of a pressure pulse effect (PE) and a subsequent semi-logarithmic (first order) inactivation during the pressure hold-time. In general, results showed that inactivation of enzymes and destruction of microorganisms was more prominent at higher-pressure levels, higher temperature and longer treatment times, and at lower pH levels of juice. Pressure pulse effect was dependent on pressure level, with higher PE achieved at higher pressures. During the pressure-hold, as expected, the associated decimal reduction times (D values) decreased with an increase in pressure. Pressure dependency of D values was well described by the conventional death time model. The pressure resistance of enzymes and microorganisms varied, but complete inactivation of enzymes and destruction of microorganisms was possible with the combination of lower pH, higher pressure and higher temperatures. / Commercial PME from a citrus source was more pressure sensitive than PME from microbial source. Spoilage bacteria (L. mesenteroides) were more pressure resistant than the yeasts. E. coli enumerated on an enrichment media (supporting both injured and healthy cells) showed larger survivors and a greater resistance than on a more selective media. An increasing number of cells got injured than killed with the application of pressure treatment until they were all finally injured or killed. High-pressure treatment (pulse at 400 MPa or by holding about 10 min at 350 MPa and 30°C) resulted in complete destruction of the pathogenic microorganism E. coli (O157:H7) ensuring the public health safety of the process.