Lecture16GrowthRegulatorsCytokinin

Hypocotyl growth cell callus growth chlorophyll

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: inin oxidase (most tissues) – Conjugation • Cytokinin glucosides – seeds use this as a store of cytokinin Plant Growth Substances - Cytokinin Detection • Bioassays – Soybean hypocotyl growth* – Cell (callus) growth – Chlorophyll retention in detached leaves • Chemical identification and characterization – Gas chromatography Plant Growth Substances - Cytokinin Detection • Bioassays – Soybean hypocotyl growth – Cell (callus) growth* – Chlorophyll retention in detached leaves it is that little stem that grows up • Chemical identification and characterization – Gas chromatography http://4e.plantphys.net/images/ Plant Growth Substances - Cytokinin Detection • Bioassays – Soybean hypocotyl growth – Cell (callus) growth – Chlorophyll retention in detached leaves* • Chemical identification and characterization – Gas chromatography Plant Growth Substances - Cytokinin Low cytokinin High cytokinin Physiological Effects • Stimulate cell division http://4e.plantphys.net/ Plant Growth Substances - Cytokinin Physiological Effects • Delay senescence • Delay breakdown of chlorophyll in detached leaves* • Stimulate nutrient mobilization – Promotes transport of many solutes from older parts of the leaf into treated zone basically cytokinin delays the loss of cell division/growth, it delays the breakdown of chlorophyll in detached leaves, it stimulates nutrient mobilization, basically promotes the transport of solutes from the older leaves to treated zone parts of the leaf. 0.45 mg Chlorophyll per g tissue loss of growth 0.4 +BAP 0.35 0.3 0.25 Control 0.2 0.15 0.1 0.05 0 0 1 Plant Growth Substances - Cytokinin 2 3 4 Time (days) 5 6 7 8 Physiological Effects also stimulates nutrients translocation. if you radio label this Amino Acid. you can see where it goes. Sur • Delay senescence • Delay breakdown of chlorophyll in detached leaves • Stimulate nutrient mobilization* Surfactant lowers the Surface tension. it changes the source sink dynamic. no cytokinin so no movement – Promotes transport of many solutes from older parts of the leaf into treated zone Plant Growth Substances - Cytokinin source sink Cytokinin-Auxin Interactions • In vitro culture – Tobacco pith experiments • High cytokinin-auxin ratio formation of shoots • Low cyt...
View Full Document

This document was uploaded on 01/17/2014.

Ask a homework question - tutors are online