BI111 Lecture Notes - Lecture 27: Jasmonate, Auxin, Gibberellin
Document Summary
Plant growth and development: to understand diversity of plant structures and life histories, need to understand role that signal response pathways play in their growth and development. Jasmonate and oligosaccharins regulate growth and have roles in plant defense. Synthesized primarily in shoot apical meristem and young stems and leaves: promotes elongation of cells, governs growth responses to light and gravity. Auxin effects on stems: frequently promotes axial elongation of stems, maintains apical dominance, inhibits growth of lateral meristems (branching, promote fruit development (cell division), inhibit leaf abscission delay in senescence. Abscission zone: form because of an increase in auxin. In roots, promote root initiation, growth of pre-existing roots, lateral branching of roots, formation of adventitious roots: only present at high concentration, at high concentrations, growth is inhibited. Inhibition means you essentially starve the plant: monicots are less affected by inhibition by auxins than eudicots, e. g. herbicide sprayed on lawn kills eudicots but not monicots.
