The Plant Circadian Clock Regulates Biotic Stress Resistance and Defense Hormone Levels

dc.contributor.advisorBraam, Janeten_US
dc.contributor.committeeMemberLwigale, Peter Yunjuen_US
dc.contributor.committeeMemberMasiello, Caroline A.en_US
dc.contributor.committeeMemberMatthews, Kathleen S.en_US
dc.contributor.committeeMemberOlson, John S.en_US
dc.creatorGoodspeed, Danielleen_US
dc.date.accessioned2014-08-26T21:42:10Zen_US
dc.date.available2014-08-26T21:42:10Zen_US
dc.date.created2013-12en_US
dc.date.issued2013-11-21en_US
dc.date.submittedDecember 2013en_US
dc.date.updated2014-08-26T21:42:10Zen_US
dc.description.abstractDiverse life forms have evolved internal clocks enabling them to monitor time and thereby anticipate the daily environmental changes caused by the earth’s rotation. The plant circadian clock regulates expression of about one-third of the Arabidopsis genome, yet the physiological relevance of this regulation is not fully understood. Here we show that the circadian clock, acting with hormone signals, provides selective advantage to plants through anticipation of and enhanced defense against herbivory and pathogen infection. I found that plants entrained in-phase with the herbivore Trichoplusia ni (T. ni) are more resistant than plants entrained out-of-phase. Similarly, when plants are inoculated with Botrytis cinerea (B. cinerea), the time-of-day at which the inoculation initially occurred significantly affects the rate of infection. Both the circadian clock and jasmonates are required for resistance to herbivory and time-of-day resistance to pathogen infection. Jasmonate and salicylate accumulation is circadian regulated, and accumulation patterns are in opposite phase to each other. I also demonstrate that the circadian clock of post-harvest cabbage (Brassica oleracea) is entrainable by light-dark cycles and results in enhanced herbivore resistance. In addition, entrainment of Arabidopsis plants and post-harvest cabbage causes cyclical accumulation of metabolites that function in plant defense. Finally, I show that the phenomenon of post-harvest entrainment and enhanced herbivore resistance is widespread among diverse crops. The evolution of the plant circadian clock not only provides a strong physiological advantage in pest defense but also can enhance the nutritional value of plant-derived food.en_US
dc.format.mimetypeapplication/pdfen_US
dc.identifier.citationGoodspeed, Danielle. "The Plant Circadian Clock Regulates Biotic Stress Resistance and Defense Hormone Levels." (2013) Diss., Rice University. <a href="https://hdl.handle.net/1911/76735">https://hdl.handle.net/1911/76735</a>.en_US
dc.identifier.urihttps://hdl.handle.net/1911/76735en_US
dc.language.isoengen_US
dc.rightsCopyright is held by the author, unless otherwise indicated. Permission to reuse, publish, or reproduce the work beyond the bounds of fair use or other exemptions to copyright law must be obtained from the copyright holder.en_US
dc.subjectCircadian clocken_US
dc.subjectJasmonatesen_US
dc.subjectBiotic stressen_US
dc.subjectHerbivoryen_US
dc.subjectCell biologyen_US
dc.titleThe Plant Circadian Clock Regulates Biotic Stress Resistance and Defense Hormone Levelsen_US
dc.typeThesisen_US
dc.type.materialTexten_US
thesis.degree.departmentBiochemistry and Cell Biologyen_US
thesis.degree.disciplineNatural Sciencesen_US
thesis.degree.grantorRice Universityen_US
thesis.degree.levelDoctoralen_US
thesis.degree.nameDoctor of Philosophyen_US
Files
Original bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
Thesis 2013 DMG.pdf
Size:
3.76 MB
Format:
Adobe Portable Document Format
License bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
license.txt
Size:
955 B
Format:
Plain Text
Description: