Greenhouse and field experiments were conducted with maleic hydrazide and gibberellic acid on the British Sovereign variety of strawberry at the University of British Columbia. Treatment with maleic hydrazide resulted in an increase in number of leaves and crowns per plant and an increase in mother plant vigour over control plants which were allowed to runner freely. In these respects the maleic hydrazide-treated plants responded similarly to those which had had their runners removed by hand. Length of runners and number of runner plants were effectively reduced. Top-root ratio on a fresh weight basis was decreased as a result of suppression of total top growth but there was no effect on root growth. Chemical analysis of plant tops 16 days after treatment with maleic hydrazide indicated increases in the percentages of dry weight, ash, sugar, starch (fresh weight) and in the carbohydrate-nitrogen ratio; and a decrease in the percentage of total nitrogen (dry weight). No change in total dry weight of tops was recorded. Field applications of 10 ounces of maleic hydrazide (active ingredient) per acre did not give adequate results with four applications at three-week intervals. Three applications at 25 ounces per acre at three-week intervals gave excellent runner control and mother plant vigour was equal to that of plants receiving hand runner removal. Two applications at 40 ounces per acre gave very good runner control hut mother plants were not as vigorous as those receiving three applications at the 25-ounce per acre rate. No effect of gibberellic acid application was noted on numbers of leaves, crowns, runners or flowers. Increase in fresh weight of tops, no change in roots and increase in top-root ratio were recorded 16 days after treatment, while total dry weight of tops was not affected. Two months after treatment, no effects were observed on fresh weight of tops, roots or top-root ratio. Flower truss emergence and flowering were hastened but did not result in earlier maturation of fruit. The percentage of fruit-set was reduced resulting in a reduction of weight of crop. Size of berry was also reduced. Other effects of gibberellic acid were an increase in sugar content of fruit when it was applied shortly before berry maturity and increases in length of peduncle and petiole if applied when these structures were making active growth. Chemical analysis of plant tops 16 days after treatment indicated decreases in the percentage of dry matter, sugar, starch (fresh weight) and in carbohydrate-nitrogen ratio. There was no change in the percentage of ash and nitrogen (dry weight) in plant tops. / Land and Food Systems, Faculty of / Graduate

No description available.

No description available.

No description available.

Graduation date: 1936

Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references. Also available on the World Wide Web.

Call number: LD2668 .T4 1979 S53 / Master of Science

Call number: LD2668 .T4 1958 B87 / Master of Science

Strawberries are a popular fruit with a pleasing color and flavor. However, its delicate tissue and high sugar content makes it highly perishable with visible mold. In this study, we have attempted to test feasibility of different edible coatings for extending shelf life of ‘Chandler’ strawberries subjected to simulated vibrations of local transportation. Six types of coatings were compared based on the quality of treated berries. Curcumin and limonene were used as natural antimicrobials and coatings were prepared from their liposomes and were over-coated with methyl cellulose. One set of each coating type were subjected to the simulated vibration of local transportation. The vibrated samples had lower shelf life than non-vibrated samples, indicating a robust coating which remains intact during road vibrations is required. Based on the number of berries with visible mold, limonene liposomes showed significantly lower fungal growth compared to the control on the 14th day of storage. Titratable acidity and total phenolic contents were also found to be higher in limonene-coated strawberries compared to other coatings. From the findings, further study of liposome coatings of limonene with different particle size and concentration of the lipid bilayer was necessary to characterize the liposome for an effective application in strawberries. To this regard, another study was done with the aim to develop and characterize alginate and limonene liposomes as edible coating materials and to determine their efficacy in shelf life extension and maintaining quality parameters of ‘Chandler’ strawberries. Alginate solution (1.5% w/v) and limonene liposomes prepared from 80% lecithin and 20% PDA were used as edible coating materials. Fungal decay percentage, total yeast and mold counts, headspace atmosphere analysis, total soluble solids, pH, titratable acidity, total anthocyanin content and total phenolics were analyzed to assess fruit quality during 14 days at 4ºC of storage. Days of storage were found to be significant in maintaining the quality of the strawberries. Among the coating types, strawberries coated limonene liposomes were found to be significantly effective in maintaining the lesser respiration rate, lower the change in pH (3.9), and had higher total anthyocyanin (43.849) content during storage. Thus, limonene liposomes were found to be useful for extending the shelf life and maintaining quality of strawberry fruits.

Typescript (photocopy). / Digitized by Kansas Correctional Industries