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A sequential imaging system using a flat bed scanner interfaced to a personal computer was developed to study seed germination and vigor. The utility of the system was demonstrated in studies relating aspects of seed vigor in impatiens seed lots and for dormancy release in two woody perennials. Impatiens seed lots were kept in storage for 6 months to obtain a range in vigor levels. The ability to see differences at the individual seed level was possible because of the development of the sequential imaging system. It was observed that seeds deteriorated both under optimum 4OC as well as 25OC storage conditions. It was determined that both germination rate and seedling growth rate were appropriate measures of seed vigor. As untreated and primed seed lots were aged, germination percentage was negatively correlated with germination rate and positively correlated with seedling growth. However, there was a lack of correlation between germination rate and seedling growth on an individual seed basis. The data suggests that germination rate and seedling growth rate appear to be measuring different aspects of vigor. Sequential imagery also showed subtle changes in seed and seedling growth as seeds came out of dormancy that would not be detectable otherwise. This technique revealed changes in seed morphology that were previously not documented for seeds with physical dormancy. The current study furthered the utility of the imaging system by the development of sequential imaging that allows for samples to be collected hourly without technician input. This permitted very accurate determinations of germination rate and seedling growth on a single seed basis.

Early evidence for the importance of legumes in nutrition is limited by difficulties in the identification and interpretation of pulse remains from archaeological contexts. The main aims of this work are to seek in a detailed survey of legume seed micromorphology, criteria that can be used i) for the identification of species and, ii) as evidence of cultivation. Assessment of the role of SEM in archaeobotany is a supplementary aim. Archaeological evidence of pulses in the Old World is first reviewed, followed by the rationale for the selection of members of the tribe Vicieae as the species researched. The second part of the thesis is a background study of the Vicieae and its four major genera Vicia, Lathyrus, Lens and Pisum. Brief accounts of their taxonomy, seed morphology and geographical distribution are followed by an examination of traditional Old World systems of pulse agronomy. Chapter three concerns the material and methods of research. The results are described qualitatively in chapter four, and following multivariate analysis in chapters five and six. The seventh chapter describes some miscellaneous procedures. The eighth chapter is a discussion of the results. Identifications down to species level using seed micromorphology are restricted to certain taxa, contrary to some published reports; but allocation of specimens to a higher taxonomic rank, using an array of criteria, is usually more realistic. Most useful characters are found in features in the hilar region. Clear evidence of cultivation has only been observed in the genus Pisum. Using SEM, similar data may be recorded equally in fresh seeds and fragments of charred archaeological specimens. It is concluded that seeds of the Vicieae usually do not exhibit sufficient morphological differences for species identification. Evidence for cultivation may rather be sought in biochemical changes that facilitate control of the germinationin seeds of cultigens. Future research into pulse biochemistry and agronomy is anticipated.

The effect of drying corn, rice and wheat seed in two stages was studied, using germinability as a measure of quality. For the first stage, fluidised bed dryer (FBD) and spouted bed dryer (SBD) were used to dry seed from 20-25%wb to 18%wb while in-store dryer (ISO) was used in the second stage for drying from 18%wb to below 14%wb. The drying air temperature range of 40-80??C was studied for the first stage while 18-30??C and relative humidity 60-70% were for the second stage. It was found that dryer type, drying temperature, initial moisture content of seeds and drying time had significant effects on the seed germination. From the result, the drying air temperature of 40??C was safe for corn and rice in FBD while 60??C was acceptable for wheat. In SBD, the 40??C was the maximum drying temperature for rice and wheat without quality deterioration. Meanwhile the second stage drying in an ISD under all specified conditions was safe. In this work, the thin-layer drying models were developed. The results showed that the modified Page's model and modified two-compartment model were the best-fitted models with the root mean square (RMS) of the differences between the predicted moisture ratio and the measured values below 0.03. Besides, the existing ISD simulation program provided the RMS of 0.3, 1.1, and 0.9%wb for corn, rice and wheat respectively. The germination models for FBD and SBD were also developed. As a result, the modified Giner's models 1&2 were the best-fitted models for FBD with the RMS of the differences between predicted and measured germination percentages of 7.9, 4.2 and 3.4% for corn, rice and wheat while the modified Giner's models 2&3 were for SBD with the RMS of 5.5 and 6.1% for rice and wheat respectively. The comparison between FBD and SBD revealed that FBD had faster drying rate while SBD consumed less energy. Ultimately, the energy cost analysis showed that single-stage drying in a fixed bed dryer using ambient condition consumed less energy than two-stage drying using a FBD and ISD but lower energy cost must be weighed against the faster drying rate, flexibility, portable design, and product uniformity of FBD.

Thesis (PhD) -- Macquarie University, School of Biological Sciences, 1988. / Bibliography: leaves 112-121. / General introduction to seed priming -- Water relations of tomato seed germination -- Water relations to tomato seeds during priming -- Water relations of germinating primed tomato seeds -- Histological study of tomato seed germination and priming -- Endosperm weakening during germination and priming of tomato seeds -- General discussion -- References. / It is the aim of this thesis to examine hypotheses regarding the prevention of radicle emergence during priming and of the enhancement of germination following priming. This work should identify the control sites in the processes of radicle emergence and their modification during priming. -- For the most part these hypotheses are underlain by an analysis of germination as a special case of plant cell expansion. A study of cell expansion requires an understanding of the water relations of the tissues involved. Therefore, the sequence of events during the germination of tomato seeds was first examined through a water relations study then the changes caused by priming were examined. -- The study of the water relations of germinating tomato seeds revealed that the seeds came into Ψ equilibrium with the imbibitional solution, whereas, the embryo was measured at much lower Ψ. There was no evidence of a lowering of embryo Ψπ nor of an increase in embryo Ψp prior to radicle emergence. The embryo Ψ measurements need to be interpreted with caution for they are ex situ measurements and thus do not directly measure these properties in the seed. It is unlikely that a large ΔΨ could be maintained within the seed during imbibition. Thus the existence of a large seed to embryo Ψp can be inferred from these measurements. The moisture release isotherm of the excised embryo confirmed this inference. The endosperm tissue enclosing the embryo was found to restrict the hydration level of the embryo prior to its emergence. As the embryo was capable of expansive growth prior to radicle emergence, it was concluded that the weakening of the endosperm controlled radicle emergence in tomato seeds. -- During priming the tomato seeds were in Ψ equilibrium with the priming solution, but the embryo was not. As the embryo was capable of growth after 2 days of the 6 day priming treatment, it was concluded that radicle emergence was prevented by the maintenance of the endosperm restraint. Germinating primed seeds did not display a marked plateau during imbibition. Both seed and embryo water contents were higher than those of non-primed seeds. However, embryo Ψ and Ψπ were lower than those of embryos from non-primed seeds, eventhough embryo Ψπ measurements during priming had not revealed significant lowering. The relative growth rate of seedlings from primed seeds was higher than that of non-primed seeds for the first 12 h after radicle emergence. / The endosperm of tomato seeds consisted of two distinct cell types found in separate locations within the seed. At the micropylar end of the seed the endosperm cells had thin walls, whereas those in the rest of the seed had thickened walls. The outer walls of outermost endosperm cells in the rest of the seed had massively thickened walls whereas these were lacking from the outer cells of the micropylar region. -- All cells, except those of the root cap, contained protein bodies. The protein bodies of the micropylar region endosperm cells were seen to breakdown to form vacuoles prior to radicle emergence. The protein bodies in other cells did not appear to change prior to this time. During priming protein body breakdown was more extensive in the micropylar region endosperm cells and vacuole formation also occurred in the radicle. After radicle emergence the cells of the radicles from primed seeds were found to be about 50% larger than those of the radicles from non-primed seeds. -- Endosperm weakening preceded radicle emergence in tomato seeds. Slower germinating seeds within the population had higher values for endosperm resistance. Endosperm weakening during priming resulted in values for endosperm resistance which were lower than those measured from a population of germinating non-primed seeds. Germinating primed seeds had resistances which were similar to those of priming seeds. It was concluded that a final rapid endosperm weakening step may be necessary for radicle emergence to occur. -- These studies have shown that tomato seeds prime because the endosperm does not weaken sufficiently to permit expansion of the radicle. The mechanism by which some endosperm weakening was permitted, but the final weakening for radicle emergence was prevented was not identifiable. Priming advanced the timing of radicle emergence by improving the rate of water uptake by the seeds; by eliminating the time necessary for the loosening of embryo cell walls and by permitting the completion of the first step of the endosperm weakening process. Enbryos from primed seeds had improved cell wall extensibilities which permitted higher relative growth rates during the first 12 h after radicle emergence. / Mode of access: World Wide Web. / x, 121 leaves, 4 leaves of plates ill

Thesis (Ph.D.)--University of Adelaide, School of Earth and Environmental Sciences, Discipline of Soil and Land Systems, 2004. / "November 2004" Includes bibliographical references (leaves 182-189). Also available online.

Thesis (Ph.D.)--University of Adelaide, School of Earth and Environmental Sciences, Discipline of Soil and Land Systems, 2004? / Includes bibliographical references. Also available in print form.

Thesis (Ph. D.)--Antioch University New England, 2008. / Title from PDF t.p. (viewed Feb. 19, 2009). "A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy Environmental Studies at Antioch University New England 2008"--The title page. Advisor: Beth A. Kaplin, Ph. D. Includes bibliographical references (p. 122-123).

Inaug.-Diss.--Göttingen. / Lebenslauf.

Thesis (M.S.)--West Virginia University, 2005 / Title from document title page. Document formatted into pages; contains viii, 108 p. : ill. Includes abstract. Includes bibliographical references.