| Summary: | 碩士 === 國立臺灣大學 === 園藝暨景觀學系 === 105 === Calcium (Ca) and phosphorus (P) are essential elements for plant growth and development. Calcium functions in maintaining structures of cell membrane and cell wall, and also serves as an important second messenger. Phosphorus is involved in the regulation of several physiological and biochemical processes, and is also an important component of cell membrane. Tomato (Solanum lycopersicum L.) is an important economic crop worldwide. Blossom-end rot (BER), a Ca related physiological disorder, had led to serious financial loss in tomato commercial production areas around the world. A lot of factors may lead to occurrence of BER, such as insufficient uptake of calcium, unbalanced partition of Ca within the cell, etc. Recent studies showed that when the transgenic plant overexpressed sCAX1 (small cation exchanger 1, a Ca2 + / H+ antiporter), more Ca2+ transport into vacuole, lower apoplastic Ca concentration and thus occurrence of BER were observed. By studying the effects of applying different concentrations of calcium and phosphate fertilizers to plants with trickle fertigation, this research intended to explore the effects of Ca and P on BER incidence and Ca transport-related genes expression. The results showed that in ‘King Kong 2’ immature-green stage fruits (15 days after pollination, 15 DAP), BER incidence and severity were not altered by high and low Ca concentration treatments, whereas high Ca concentration treatment reduced expression levels of most Ca transport-related genes. In ‘King Kong 2’ mature-green stage fruits (45 DAP), high Ca concentration treatment significantly reduced BER incidence and severity, and reduced expression levels of most Ca transport-related genes. BER incidence and severity of 15 DAP and 45 DAP fruit of other cultivars were not significantly altered by Ca treatment, whereas high Ca concentration treatment reduced expression levels of most Ca transport-related genes. In comparison to low P concentration treatment, high P concentration treatment reduced BER incidence and severity of ‘Taiwan Seed ASVEG #15’ red stage fruits as well as expression levels of ATPase 4, ATPase 7 and ATPase 8. BER incidence was low in ‘Mei Huei’ and ‘CLN2460L’, so that the effect of high P concentration treatment on BER incidence and severity could not be easily observed, while high P concentration treatment reduced expression levels of ATPase 4 and ATPase 7. Above results indicated that both high Ca and high P concentration treatments reduced BER incidence and severity of ‘King Kong 2’ and ‘Taiwan Seed ASVEG #15’, probably due to reduced expressions of Ca transport-related genes.
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