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Bibliography: leaves 89-104. / vi, 104 leaves, [15] 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. / In this study an EMS-mutated Arabidopsis mutant pho2, which accumulates Pi in leaves, was used to study Pi uptake and transport by comparing it to wild-type seedlings. The study aimed to define the physiological lesions in pho2 mutant and to obtain evidence regarding the function of the PHO2 gene in P nutrition in higher plants. Accumulation of Pi in leaves of pho2 was found to reside in the symplast and was not related to Zn-deficiency. The physiology of the pho2 mutant is consistent with either a block in Pi transport in phloem from shoots to roots or an inability of shoot cells to regulate internal Pi concentration. Southern block analysis revealed that the two transporter genes, APT1 and APT2 were not responsible for the pho2 mutant. Data from the mapping of the PHO2 gene along with information from the Arabidopsis genome sequencing will form the basis for cloning the PHO2 gene in the future. / Thesis (Ph.D.)--University of Adelaide, Dept. of Plant Science, 1999

Typescript (photocopy) / xx, 170 leaves : ill. (part col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Agricultural Biochemistry and Soil Science, 1978

The measurement of phosphorus which is available to plants is a problem closely related to the forms and amounts of phosphorus present in soils. The fractionation of soil phosphorus, based on a series of extractions, is a procedure that has been utilized by many investigators. In this study, this scheme was utilized in an attempt to improve and evaluate the effectiveness of some methods employed in the measurement of available phosphorus to plants. / Ph. D.

A loblolly pine phosphorus fertilization trial was evaluated 20 years after establishment on a Tatum silt loam in the Virginia Piedmont. Triple superphosphate (TSP) was applied at 160 kg P/ha and ground rock phosphate (GRP) was applied at both 160 kg P/ha and 670 kg P/ha. Lime (4.48 T/ha) was applied with and without the TSP treatment. Tree growth was not significantly affected by treatment and foliar phosphorus levels were above 0.10% indicating that a deficiency was not the immediate growth limiting factor. Double-acid-extractable soil phosphorus critical levels established for the Coastal Plain do not appear useful for diagnosing tree requirements for this Piedmont soil. A critical level of 1.0 ppm double-acid-extractable phosphorus would be more applicable to this soil. GRP was more effective than TSP after 20 years at increasing phosphorus uptake, probably due to a slower dissolution rate and the inclusion of F-ions which reacted with soil Al to reduce phosphorus fixation. Although an increase in the A horizon pH persisted for 20 years, there was no increase in phosphorus uptake as a direct response to this higher pH. Liming may have some long-term merit when applied in conjunction with a water soluble phosphorus fertilizer such as TSP by reducing the transformations of applied phosphorus to unavailable forms. / Master of Science

A greenhouse study was initiated to asses P uptake, growth, colonization, total mycorrhizal P levels, and mycorrhizal polyphosphate levels in loblolly pine seedlings colonized with different ectomycorrhizal fungi and grown in a Piedmont soil. The pine seedlings were inoculated with one of four species of fungi (Scleroderma aurantium, Pisolithus tinctorius, Thelephora terrestris, and Rhizopogon roseolus). Uninoculated trees served as a control. The seedlings were grown in pots containing a Cecil sandy clay loam amended with one of the following: 75% sand, 25% sand, enamended, 56 kg P ha⁻¹, 112 kg P ha⁻¹. They were harvested ten months after planting. Shoot lengths, root lengths, biomass, and total P of all plant parts including mycorrhizae were determined. Mycorrhizae of T terrestris and S aurantium were analyzed for polyphosphates, and amended soils were analyzed before planting and after harvest for double-acid extractable Al, Fe, and P. Each fungus changed postharvest extractable P, Fe, and Al differently in the soil amendments. Seedlings colonized with S. aurantium were larger, contained more P, and had a higher degree of mycorrhizal colonization. There was no significant differences in growth among seedlings colonized with the other three fungi, but all colonized seedlings were significantly larger and contained more P than uncolonized seedlings. Soil amendments had no effect on the total levels of mycorrhizal P. Mycorrhizae of S. aurantium increased polyphosphate levels with increasing available P in the soil amendments. The pattern of polyphosphate accumulation in T. terrestris among the soil treatments was less definitive. Accumulation of foliar P was affected by the interaction of soil and mycorrhizal treatments. Control seedlings were P deficient in all soil treatments although foliar P increased as soil P increased. The accumulation of foliar P seemed to reflect the ability of each symbiont to survive, uptake P, and transfer it to the seedling. Seedlings colonized with S. aurantium were P deficient in sand-amended soils, while seedlings colonized with R. roseolus were P deficient in fertilized soils. Seedlings colonized with either P. tinctorius or t. Terrestris increased foliar P with the addition of sand the addition of P. This study indicates that S. aurantium is adapted to Piedmont soils such as the Cecil, is able to extract more of the vast amount of unavailable P present in these soils, and hence stimulate growth and P levels in loblolly pine. / Ph. D.

Zhang Siyi. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 97-109). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstract --- p.iii / List of Tables --- p.vii / List of Figures --- p.viii / List of Abbreviations --- p.x / Chapter Chapter 1: --- General Introduction --- p.1 / Chapter Chapter 2: --- Literature Review --- p.3 / Chapter 2.1 --- Phosphorus and higher plants --- p.3 / Chapter 2.1.1 --- Phosphorus is a macronutrient in higher plants --- p.3 / Chapter 2.1.2 --- The forms of phosphorus in plant cells --- p.3 / Chapter 2.1.3 --- Phosphorus compartments and pools in plant cells --- p.6 / Chapter 2.2 --- The acquisition of phosphorus in higher plants --- p.8 / Chapter 2.2.1 --- The forms of phosphorus absorbed by higher plants --- p.8 / Chapter 2.2.2 --- Soil phosphorus bioavailability --- p.9 / Chapter 2.2.3 --- Uptake and transportation of phosphorus --- p.10 / Chapter 2.3 --- Adaptive responses of higher plants to phosphorus deficiency --- p.11 / Chapter 2.3.1 --- Phosphorus homeostasis --- p.12 / Chapter 2.3.2 --- Enhancement of phosphorus uptake --- p.14 / Chapter 2.3.3 --- Phosphorus scavenging and recycling --- p.16 / Chapter 2.4 --- Regulation of gene expression under phosphorus starvation --- p.18 / Chapter 2.5 --- Acid phosphatase and purple acid phosphatase in plants --- p.22 / Chapter 2.5.1 --- Acid phosphatases --- p.22 / Chapter 2.5.2 --- Purple acid phosphatase (PAP) --- p.26 / Chapter Chapter 3: --- Hypothesis --- p.31 / Chapter Chapter 4: --- Materials and Methods --- p.33 / Chapter 4.1 --- Materials --- p.33 / Chapter 4.1.1 --- Chemicals --- p.33 / Chapter 4.1.2 --- Plant materials --- p.33 / Chapter 4.1.3 --- Plasmid vectors and bacterial strains --- p.33 / Chapter 4.1.4 --- DNA sequencing --- p.34 / Chapter 4.1.5 --- Softwares: --- p.34 / Chapter 4.2 --- Methods: --- p.35 / Chapter 4.2.1 --- Survey of PAP occurrence in higher plants --- p.35 / Chapter 4.2.2 --- Determination of multi-gene family and gene copy number of PAPin tomato genome --- p.40 / Chapter 4.2.3 --- Effect of environmental Pi on the morphology of tomato and APase induction --- p.43 / Chapter 4.2.4 --- PAP expression in tomato seedlings growing at different Pi concentrations --- p.46 / Chapter 4.2.5 --- Genomic library construction and PAP promoter isolation --- p.48 / Chapter 4.2.6 --- PAP promoter activity assay by transient expression of reporter gene..… --- p.52 / Chapter Chapter 5: --- Results --- p.56 / Chapter 5.1 --- Identification of PAP gene in higher plants --- p.56 / Chapter 5.1.1 --- Design of primers and total RNA extraction --- p.56 / Chapter 5.1.2 --- RT-PCR --- p.57 / Chapter 5.1.3 --- Further investigation of PAP homologous sequences in monocotyledons --- p.60 / Chapter 5.2 --- Determination of multi-gene family and gene copy number of tomato PAP gene (TPAP 1) --- p.62 / Chapter 5.2.1 --- Determination of TPAP 1 copy number --- p.62 / Chapter 5.2.2 --- Determination of tomato PAP multi-gene family --- p.63 / Chapter 5.3 --- Effect of environmental phosphorus on the morphology of tomato seedling and APase induction --- p.66 / Chapter 5.3.1 --- Morphological changes of tomato seedlings under phosphorus starvation --- p.66 / Chapter 5.3.2 --- Acid phosphatase assays --- p.72 / Chapter 5.4 --- The phosphorus-regulated expression of tomato PAP --- Northern blot analysis --- p.74 / Chapter 5.5 --- Genomic library construction and PAP promoter isolation --- p.76 / Chapter 5.6 --- PAP promoter sequence --- p.79 / Chapter 5.7 --- Promoter activity assay through transient expression of reporter gene --- p.84 / Chapter 5.7.1 --- Effect of untranslation region of PAP gene --- p.84 / Chapter 5.7.2 --- Assay of PAP promoter activities regulated by phosphorus --- p.85 / Chapter Chapter 6: --- Discussion --- p.88 / Chapter 6.1 --- The wide occurrence and high conservation of plant PAP --- p.88 / Chapter 6.2 --- Tomato as a model plant and the organization of PAP gene in genome --- p.89 / Chapter 6.3 --- Morphological changes of tomato under phosphorus starvation and the induction of APase --- p.90 / Chapter 6.4 --- Regulation of PAP in tomato --- p.92 / Chapter 6.5 --- Isolation of PAP promoter --- p.92 / Chapter 6.6 --- Assay of PAP promoter activity --- p.93 / Chapter 6.7 --- Future perspectives --- p.94 / Chapter Chapter 7: --- Conclusion --- p.95 / References --- p.97

Suen Pui Kit. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 154-168). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstract --- p.iii / List of Figures --- p.vii / List of Tables --- p.ix / List of Abbreviations --- p.x / Chapter Chapter 1: --- Introduction --- p.1 / Chapter Chapter 2: --- Literature Review --- p.3 / Chapter 2.1 --- Phosphorus and Plants --- p.3 / Chapter 2.1.1 --- Importance of phosphorus --- p.3 / Chapter 2.1.2 --- Phosphorus is a limiting nutrient --- p.3 / Chapter 2.2 --- Responses of Plants to Phosphate Deficiency --- p.4 / Chapter 2.2.1 --- Morphological changes of plants during phosphate deficiency --- p.5 / Chapter 2.2.1.1 --- Modification of the root system --- p.5 / Chapter 2.2.1.2 --- Symbiotic association of roots with mycorrhiza --- p.6 / Chapter 2.2.2 --- Maintenance of phosphate levels in plants during phosphate deficiency --- p.7 / Chapter 2.2.2.1 --- Phosphate homeostasis in plants --- p.7 / Chapter 2.2.2.2 --- "Enhancement of Pi scavenging, recycling and uptake" --- p.9 / Chapter 2.2.2.3 --- Pi-limited metabolism --- p.11 / Chapter 2.2.3 --- Hormones and phosphate starvation responses --- p.12 / Chapter 2.2.4 --- Regulation of gene expression during phosphate starvation --- p.14 / Chapter 2.2.4.1 --- The pho regulon in bacteria and yeast --- p.14 / Chapter 2.2.4.2 --- The coordination of phosphate starvation induced genes in plants --- p.19 / Chapter 2.2.4.3 --- Signaling phosphate starvation --- p.19 / Chapter 2.2.4.4 --- Phosphite and phosphate starvation --- p.21 / Chapter 2.2.4.5 --- Transcriptional regulation during phosphate starvation --- p.22 / Chapter 2.3 --- Acid Phosphatases in Higher Plants --- p.26 / Chapter 2.3.1 --- Enzymatic properties of acid phosphatases --- p.26 / Chapter 2.3.2 --- Localization and function of acid phosphatases --- p.27 / Chapter 2.3.3 --- Expression of acid phosphatases --- p.28 / Chapter 2.4 --- Purple Acid Phosphatases --- p.29 / Chapter 2.4.1 --- Properties of purple acid phosphatases --- p.29 / Chapter 2.4.2 --- Regulation and expression of plant purple acid phosphatase --- p.32 / Chapter 2.5 --- Tomato Purple Acid Phosphatases --- p.33 / Chapter 2.6 --- Promoter Analysis --- p.35 / Chapter 2.6.1 --- Structure of an eukaryotic promoter --- p.35 / Chapter 2.6.2 --- Promoter analysis by deletion mapping --- p.37 / Chapter 2.6.3 --- The computational approaches in promoter analysis --- p.38 / Chapter 2.6.4 --- Transient expression assay and transgenic expression assay --- p.39 / Chapter 2.7 --- Transcriptional Regulation of Tomato Purple Acid Phosphatase Expression --- p.40 / Chapter 2.8 --- Hypothesis --- p.41 / Chapter Chapter 3: --- Materials and Methods --- p.43 / Chapter 3.1 --- Introduction --- p.43 / Chapter 3.2 --- Materials --- p.44 / Chapter 3.2.1 --- Chemicals --- p.44 / Chapter 3.2.2 --- Plant materials --- p.44 / Chapter 3.2.3 --- Plasmid vectors and bacterial strains --- p.44 / Chapter 3.2.4 --- Primers design --- p.45 / Chapter 3.2.5 --- Confirmation of sequence fidelity --- p.46 / Chapter 3.3 --- Cloning of the TPAP1 Promoter Fragments --- p.46 / Chapter 3.3.1 --- Genomic DNA extraction --- p.46 / Chapter 3.3.1.1 --- Materials --- p.46 / Chapter 3.3.1.2 --- Procedures --- p.47 / Chapter 3.3.2 --- Cloning strategy of TPAP1 promoter --- p.47 / Chapter 3.3.3 --- TPAP1 promoter cloning --- p.48 / Chapter 3.3.3.1 --- Long-distance PCR --- p.48 / Chapter 3.3.4 --- Chimeric gene constructs --- p.48 / Chapter 3.3.4.1 --- Chimeric gene construction for particle bombardment --- p.51 / Chapter 3.3.4.2 --- Chimeric gene construction for tobacco transformation --- p.51 / Chapter 3.4 --- Transient Expression Assay of the TPAP1 Promoter Fragments --- p.54 / Chapter 3.4.1 --- TPAP1 promoter activity assay --- p.54 / Chapter 3.4.2 --- Preparation of MS culture medium --- p.54 / Chapter 3.4.3 --- Growing tomato seedlings in MS liquid medium --- p.56 / Chapter 3.4.4 --- Biolistic bombardment --- p.56 / Chapter 3.4.5 --- GUS histochemcial staining --- p.57 / Chapter 3.4.5.1 --- Materials --- p.57 / Chapter 3.4.5.2 --- Procedures --- p.57 / Chapter 3.5 --- Transgenic Assay of the TPAP1 Promoter Fragments --- p.58 / Chapter 3.5.1 --- Materials for tobacco transformation --- p.58 / Chapter 3.5.2 --- Agrobacterium tumefaciens preparation --- p.58 / Chapter 3.5.3 --- Tobacco transformation and regeneration --- p.59 / Chapter 3.5.4 --- Promoter activity analysis --- p.60 / Chapter 3.5.4.1 --- Materials --- p.60 / Chapter 3.5.4.2 --- Procedures --- p.60 / Chapter 3.5.5 --- Southern blot analysis --- p.61 / Chapter 3.5.6 --- RNA isolation --- p.61 / Chapter 3.5.6.1 --- Materials --- p.61 / Chapter 3.5.6.2 --- Procedures --- p.61 / Chapter 3.5.7 --- Northern blot analysis --- p.62 / Chapter 3.6 --- Biochemical Analysis of Acid Phosphatase Activities --- p.63 / Chapter 3.6.1 --- Excretion of acid phosphatase into the environment --- p.63 / Chapter 3.6.2 --- Growing tomato seedlings in MS medium --- p.63 / Chapter 3.6.3 --- Acid phosphatase activity assay by p-nitrophenyl phosphate --- p.64 / Chapter 3.6.4 --- Activity-gel detection --- p.65 / Chapter 3.6.4.1 --- Materials --- p.65 / Chapter 3.6.4.2 --- Procedures --- p.65 / Chapter 3.7 --- "Sequence Analysis of the TPAP1 gene, cDNA and promoter" --- p.66 / Chapter 3.7.1 --- Isolation of TPAPl cDNA --- p.66 / Chapter 3.7.1.1 --- Rapid amplification of cDNA ends (RACE) --- p.66 / Chapter 3.7.1.2 --- RT-PCR --- p.67 / Chapter 3.7.2 --- Isolation of TPAP1 gene --- p.67 / Chapter 3.7.2.1 --- PCR amplification of the TPAP1 gene --- p.67 / Chapter 3.7.2.2 --- TPAP1 gene sequence determination --- p.68 / Chapter 3.7.3 --- Sequence analysis --- p.69 / Chapter 3.8 --- Statistical analysis --- p.70 / Chapter Chapter 4: --- Results --- p.72 / Chapter 4.1 --- "Cloning of the TPAP1 Promoter Fragments, Gene and cDNA" --- p.72 / Chapter 4.1.1 --- TPAP1 promoter fragment constructs --- p.72 / Chapter 4.1.2 --- TPAP1 cDNA cloning --- p.72 / Chapter 4.1.3 --- TPAP1 gene cloning --- p.72 / Chapter 4.2 --- "Sequence analysis of the TPAP1 promoter, gene, cDNA and predicted amino acid sequence" --- p.76 / Chapter 4.2.1 --- "The DNA sequence of the TPAP1 promoter, gene and cDNA" --- p.76 / Chapter 4.2.2 --- Properties of TPAP1 cDNA and protein --- p.83 / Chapter 4.2.3 --- Identification of potential metal ligating residues on TPAP1 --- p.85 / Chapter 4.2.4 --- Phylogenetic relationship of TPAPl to other plant PAPs --- p.86 / Chapter 4.2.5 --- Sequence comparison of 5'UTR ofTPAPl and NtPAP12 --- p.89 / Chapter 4.3 --- APase Activity Assay --- p.90 / Chapter 4.3.1 --- p-NPP APase activity assay --- p.90 / Chapter 4.3.2 --- Activity-gel detection --- p.90 / Chapter 4.4 --- "Comparison of TPAP 1, IAP，SAP 1 and SAP2" --- p.96 / Chapter 4.5 --- Potential Cis-acting Regulatory Elements (CAREs) on the TPAP1 Promoter --- p.100 / Chapter 4.5.1 --- Search for potential CAREs --- p.100 / Chapter 4.5.2 --- Functions of CAREs --- p.100 / Chapter 4.6 --- Transient Expression Analysis --- p.102 / Chapter 4.6.1 --- Biolistic bombardment of TPAP1 promoter fragments into tomato roots --- p.102 / Chapter 4.7 --- Transgenic Expression Analysis --- p.104 / Chapter 4.7.1 --- Transformation of tobacco --- p.104 / Chapter 4.7.2 --- Northern and RT-PCR analysis of GUS expression --- p.110 / Chapter 4.7.3 --- GUS activity analysis --- p.114 / Chapter 4.7.4 --- Histochemical staining of GUS --- p.123 / Chapter Chapter 5: --- Discussions --- p.135 / Chapter 5.1 --- Properties ofTPAPl --- p.135 / Chapter 5.1.1 --- "Structure of the TPAP1 promoter, gene and cDNA" --- p.135 / Chapter 5.1.2 --- Potential flmction(s) ofTPAPl --- p.135 / Chapter 5.1.3 --- The potential relationship between TPAP1 and NtPAP12 --- p.137 / Chapter 5.2 --- Induction of Secretory APases during Pi Starvation --- p.137 / Chapter 5.3 --- Putative Protein Encode by theTPAP 1 cDNA --- p.138 / Chapter 5.4 --- Promoter Analysis of TPAP1 --- p.140 / Chapter 5.4.1 --- Construct preparation --- p.140 / Chapter 5.4.2 --- Potential CAREs located on the TPAP1 promoter --- p.141 / Chapter 5.4.3 --- Transient expression analysis --- p.142 / Chapter 5.4.4 --- Transgenic expression analysis --- p.143 / Chapter 5.4.4.1 --- Northern analysis and RT-PCR analysis of GUS expression --- p.143 / Chapter 5.4.4.2 --- GUS activity analysis --- p.143 / Chapter 5.4.4.3 --- Histochemical staining of GUS --- p.145 / Chapter 5.5 --- Hypothetical Model for TPAP1 Promoter Activities --- p.146 / Chapter 5.5.1 --- Model for expression level --- p.146 / Chapter 5.5.2 --- Models for spatial expressions --- p.148 / Chapter 5.6 --- Future Perspectives --- p.150 / Chapter Chapter 6: --- Conclusions --- p.152 / References --- p.154