Sporulation is a process of differentiation that allows capable cells to go into a dormant and resistant stage of life. To become active again, the spores must germinate into vegetative cells. One key process in spore germination is hydrolysis of the cortex peptidoglycan. This process has been studied in a variety of sporulating species; however, it has not been studied in <i>Bacillus anthracis</i>. A clear understanding of cortex degradation may provide information that will allow for better cleanup of spore contaminated sites. The structure of cortex peptidoglycan of <i>Bacillus anthracis</i> was characterized. The peptidoglycan of the dormant spores was extracted, digested with Mutanolysin, and analyzed using HPLC to determine the structure. The analyses revealed that the cortex peptidoglycan of <i>B. anthracis</i> was very similar to other <i>Bacillus sp.</i>. Spores were stimulated to germinate and cortex peptidoglycan was extracted and analyzed at various times. <i>Bacillus anthracis</i> appeared to hydrolyze its cortex more rapidly than other <i>Bacillus </i>species. While the spores of three species release the spore solute dipicolinic acid and resume metabolism at similar rates, the <i>B. anthracis </i> spores released 75% their cortex material within 10 minutes while the other species released only 20% in the same time frame. This suggests that the <i>B. anthracis</i> spore coats are more permeable to cortex fragments than those of the other species, or that <i>B. anthracis</i> rapidly cleaves the cortex into smaller fragments. Novel cortex fragments analyzed during <i>B. anthracis</i> germination were produced by a glucosaminidase; however, additional studies need to be performed for confirmation. / Master of Science

Abstract Weather conditions during the growing season are determining the size and quality of the Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) seed crop in northern areas. Pathogens, fungi, and insects also have an effect on seed crops. The varying quality of seeds from forest stands and seed orchards does not full fill the germination requirements of tree nurseries. Multi-phase pre-treatment are therefore used in forest tree seed centres to improve seed lots quality. The main objectives of this study were to analyse long-term variation in the size and quality of Scots pine seed crops in Northern Finland. Determine the impact of fungal injuries on the structures of Norway spruce seeds. To detect changes in the germination capacity and rate of Norway spruce seeds during pre-treatment phases and to determine the impacts of short-term and long-term storage on the germination of treated seeds. The study found that in most years, regeneration of Scots pine in Northern Finland is limited by quantity as well as quality the seed crop. The long-term average of the Scots pine seed crop was 77seeds/m2 and the long-term average expected germination percentage was 61%. Aeciospores of the inlad spruce cone rust Chrysomyxa pirolata (Körnicke) Wint. were found to form inside Norway spruce seeds, destroying the nucellar layers and reducing germination of seeds. In general, the germination capacity and rate of Norway spruce seeds increased during pre-treatment phases. The germination capacity of seeds increased about 30% and the rate by more than 40% during pre-treatment. During long-term storage the germination capacity and rate of pre-treated Scots pine seeds were preserved better in frozen storage than in cool storage. It was found that pre-treated Scots pine forest stand seeds can be stored for several years in frozen conditions. The germination capacity and rate of pre-treated orchard seeds were effected significantly more than those from forest stands. It is therefore recommended that Scots pine seeds from orchards be stored without pre-treatment. The germination capacity and rate of treated Norway spruce seeds from orchards was not significantly different after one year of storage.

Call number: LD2668 .T4 1961 S66

Call number: LD2668 .T4 1984 H46 / Master of Science

published_or_final_version / Botany / Master / Master of Science

Chickpea (Cicer Arietinum) was germinated for different lengths of time to determine the influence of germination on the functional and nutritional properties of this legume. Chemical analysis of the flours showed a very significant increase in vitamin C and in lysine during germination. Vitamin C values ranged from 1.2 to 15.6 mg/100 g and lysine from 10.5 to 13.5 g/100g of protein for the intact and the 48 hr-germinated chickpea, respectively. Starch content decreased 15.5% and soluble sugars increased 20% after only 24 hr of germination. Germination decreased trypsin inhibitor activity by 28%. Chickpea and 24 hr germinated chickpea were used as ingredients in the preparation of several products. Germination increased acceptability in some of these products by modifying their rheological and sensory properties. Seed germination enhanced significantly the nutritional quality of chickpea protein. Protein efficiency ratio associated with the germinated chickpea diets compared favorably to that obtained with the casein diet. Protein digestibility decreased as germination time increased. Essential amino acid availability did not change after 24 hr of germination, but small decreases were observed after 48 hr. Protein and starch were studied separately to determine their influence on the observed modifications. No significant changes were found in the concentration of proteins in germinated chickpea even after 72 hr of germination as indicated by densitometry scans of SDS-PAGE patterns. Starch was isolated from intact and germinated chickpeas and characterized by several of its physicochemical properties and its susceptibility to alpha-amylase hydrolysis. Germination increased substantially starch digestibility and modified some of the physico-chemical properties of starch. Scanning electron microscopy (SEM) showed no apparent differences between starches except for a tendency of the germinated chickpea starch to clump. These results suggest that changes in texture, consistency and other physical parameters observed on the germinated chickpea-based products may be attributed mostly to starch.

This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.

Experiments were conducted to determine if there was a residual effect of the experimental plant growth regulator Ortho XE-1019, (E)-(P-chlorophenyl)-4,4-dimethyl-2-1,2,4-triazol-l-yl)-l-penten-3-01, remaining in Deltapine 50 and 90 cottonseed obtained at three harvest dates from experiments run at the University of Arizona Marana and Maricopa Agricultural Centers in 1986. Commercial DPL 50 seed were treated with XE-1019 in a second experiment. Several growth characteristics were measured including dry weights after 7 and 12 days. Hypocotyl length was not significantly different between treatments after 12 days of growth, with one exception, nor between dates of harvest for DPL 90 and DPL 50. Other measurements sometimes had statistical differences which were more academic but would be of little consequence in obtaining a satisfactory field stand. A significant reduction of hypocotyl length resulted when seed was directly treated with XE-1019 and would result in poor emergence. Results indicated that the use of XE-1019 as a plant growth regulator on cotton would not have significant residual responses on early seedling growth of Deltapine 90 and Deltapine 50 when the resulting seed are used for planting seed in the next generation.

Nine cycles of recurrent selection for germination salt tolerance in alfalfa (Medicago sativa L.) were compared with their parental cultivar, 'Mesa-Sirsa'. Test seeds were produced in the same season and locale. Cycle 9 and Mesa-Sirsa showed 90% and 2.5% germination, respectively, in a -1.7 MPa NaCl medium. Cycle 8 germinated more vigorously compared to Mesa-Sirsa in stressed and non-stressed environments. Selection also enhanced germination speed and radicle length. Fresh seed and one year old seed showed similar percent germination. Scarification decreased germination in a saline solution. Mesa-Sirsa and Cycle 8 displayed the same pattern of water uptake in a salt solution. Salinity decreased water uptake in Cycle 8 and Mesa-Sirsa compared to the control. Cycle 8 and Mesa-Sirsa contained 7% galactomannan and 3.2% stachyose. Galactomannan was not an important factor in seed salt tolerance. Seed protein content was stable throughout the cycles of selection. Selection for germination salt tolerance in alfalfa significantly affected the percentage of seed amino acids.

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