1 / 16

Flowering time control in Arabidopsis - The relationship between phyllochron and flowering time

Department of Agronomy, KSU. 2002 ASA Meeting. Flowering time control in Arabidopsis - The relationship between phyllochron and flowering time. Z. Dong, S. M. Welch Agronomy Dept., Kansas State Univ. Department of Agronomy, KSU. Arabidopsis thaliana. Introduction.

varick
Download Presentation

Flowering time control in Arabidopsis - The relationship between phyllochron and flowering time

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Department of Agronomy, KSU 2002 ASA Meeting Flowering time control in Arabidopsis -The relationship between phyllochron and flowering time Z. Dong, S. M. WelchAgronomy Dept., Kansas State Univ.

  2. Department of Agronomy, KSU Arabidopsis thaliana Introduction • A member of the Brassicaceae, the mustard family • Main characteristics: • Rapid generation time • Thousands of seeds • Morphologically simple • Small genome size – 25,000 genes • Widely used in molecular genetics, developmental biology

  3. Department of Agronomy, KSU Objectives Objective • Two concepts that are common in crop modeling have not been studied in Arabidopsis • Phyllochron interval • Flowering developmental rates

  4. Department of Agronomy, KSU Some Standard Measures Methodology • Growing degree days • Photothermal time (Masle et al., 1989) • Days after planting / emergence

  5. Autonomouspathway Photoperiod pathway CircadianClock Temperature Cold Light FPA CRY2 GI Vernalizationpathway FVE PHYB CO FCA FLC Gibberellinpathway FT SOC1 The FLC allele in the Ler background is nearly a loss of function mutation LFY Adopted from various literature Department of Agronomy, KSU Methodology

  6. Department of Agronomy, KSU Growth Chamber Experiments Methodology • Seven flowering time mutants and wild type, Ler, were used • 2 x 2 factorial CR design • Temperature: 16, 24oC • Photoperiod: 8, 16 hr. light/day • Daylength and temperature were recorded • Leaf number and flowering time were observed

  7. Department of Agronomy, KSU Estimation of Base Temperature -Least Variability Method Results

  8. Department of Agronomy, KSU Estimation of Base Temperature -RLA vs. Mean Temperature Results • Tb=-b/a, here a and b are the intercept & the slope of the straight line, respectively • Tb values estimated from RLA are unreasonable

  9. Department of Agronomy, KSU Estimation of Base Temperature -DRF vs. Mean Temperature Results • Calculate Tb by data from inductive DL & non-inductive DL • Results are better than those from the previous two methods

  10. Department of Agronomy, KSU Estimation of Phyllochron Results • RLA is the slope of the straight line • Phyllochron is the inverse of RLA Trt 1Ler Trt 1LerTb=0 Trt 1LerTb=0

  11. Department of Agronomy, KSU Define Developmental Unit Results ki = DU/day for treatment i Pj = Phyllochron for genotype j bj = Intercept for genotype j LNij(D) = Leaf number at day D for genotype j in treatment i

  12. Department of Agronomy, KSU Developmental Unit for Treatments Results

  13. Department of Agronomy, KSU Relationship among DU and T and DL Results • DU is closely dependent on temperature and photoperiod but not their interaction (R2=0.886)

  14. Department of Agronomy, KSU Results Ler

  15. Department of Agronomy, KSU - fca-6 - fpa-2 - fve-2 - co-6 - fha-1 - gi-6 - phyB-1 - Ler Results

  16. Department of Agronomy, KSU Conclusion Conclusion • Estimates of Tb are unreasonable in situations where fundamental genetic control networks are compromised • Linear relationships exist between leaf number and time (DU, DAP, GDD, or PTT) • A DU system can be defined with constant phyllochron intervals across environments for each genotype • In this system developmental units (DU) are linearly related to temperature and photoperiod • The relationship between rate of leaf appearance and flowering developmental rate is weak (-0.1789)

More Related