Hormonal and Environmental Regulation of Seed Germination Rates

种子萌发是植物生命周期的关键阶段， 在生态和农业方面， 内源激素和环境因素。 定量 数学模型已被开发来表征响应 脱落酸（阿坝）、赤霉素（GA）和 水势（psi）。 番茄的单基因突变 （Lycopersicon esculentum Mill.）导致阿坝缺乏 或GA对休眠、发芽率和 对减小的psi的敏感性。 这个项目将利用这些突变体 在数学模型提供的框架内的基因型 以确定控制发芽的生化过程。 当胚乳细胞层与胚根相对时， 顶端变弱并分开以允许胚扩展。 细胞壁 胚乳组织中的水解作用及其与 将研究发芽率。 番茄的成分 胚乳细胞壁将被表征，底物， 产品，和酶参与细胞壁水解将是 鉴定，以及细胞壁水解与组织的关系 弱化将在突变体和野生型中进行批判性分析 种子 种子萌发数学描述的扩展 生理和生化水平提供了一个强大的新的 用于研究工厂中调节控制的集成的方法 发展

Seed germination is a critical phase of the plant life cycle, both ecologically and agriculturally, and is sensitive to both endogenous hormones and environmental factors. A quantitative mathematical model has been developed to characterize the responses of seed germination to abscisic acid (ABA), gibberellins (GA), and water potential (psi). Single-gene mutations in tomato (Lycopersicon esculentum Mill.) resulting in deficiencies of ABA or GA have contrasting effects on dormancy, germination rates, and sensitivity to reduced psi. This project will utilize these mutant genotypes within the framework provided by the mathematical model to identify the biochemical processes controlling germination. Germination occurs when endosperm cell layers opposite the radicle tip weaken and separate to allow embryo expansion. Cell wall hydrolysis in this endosperm tissue and its relationship to germination rates will be investigated. The composition of tomato endosperm cell walls will be characterized, the substrates, products, and enzymes involved in cell wall hydrolysis will be identified, and the relationship of cell wall hydrolysis to tissue weakening will be critically analyzed in mutant and wild-type seeds. Extending the mathematical description of seed germination to the physiological and biochemical levels provides a powerful new method for studying the integration of regulatory controls in plant development.