ABSTRACT
This chapter begins with a brief discussion of basic plant biology and physiology, emphasizing topics important to senescence. It examines the mechanism of senescence in plants and look at factors that initiate senescence. The chapter considers plant senescence and focuses primarily on aspects of plant biology that differ from animal biology. Genetically engineering plants to delay or prolong plant senescence results in improved nutrient content of seeds and fruits and increased crop yields. The chapter discusses cytokinins, abscisic acid, ethylene, salicylic acid, and jasmonates have all been shown to be important in plant senescence, and their roles in senescence. Plant senescence evolved somewhat differently. Plant senescence, although causing the death of the plant or plant parts, is not a by-product of genes selected for reproduction or a chance event that leads to age-related decline in physiological function. The vast majority of plant cells are postmitotic, and most research has focused on the mechanism underlying senescence in these cells.
