Plant Reproduction

, Volume 27, Issue 3, pp 121–127 | Cite as

High humidity partially rescues the Arabidopsis thaliana exo70A1 stigmatic defect for accepting compatible pollen

  • Darya Safavian
  • Muhammad Jamshed
  • Subramanian Sankaranarayanan
  • Emily Indriolo
  • Marcus A. Samuel
  • Daphne R. Goring
Original Article


We have previously proposed that Exo70A1 is required in the Brassicaceae stigma to control the early stages of pollen hydration and pollen tube penetration through the stigmatic surface, following compatible pollination. However, recent work has raised questions regarding Arabidopsis thaliana Exo70A1’s expression in the stigma and its role in stigma receptivity to compatible pollen. Here, we verified the expression of Exo70A1 in stigmas from three Brassicaceae species and carefully re-examined Exo70A1’s function in the stigmatic papillae. With previous studies showing that high relative humidity can rescue some pollination defects, essentially bypassing the control of pollen hydration by the Brassicaceae dry stigma, the effect of high humidity was investigated on pollinations with the Arabidopsis exo70A1-1 mutant. Pollinations under low relative humidity resulted in a complete failure of wild-type compatible pollen acceptance by the exo70A1-1 mutant stigma as we had previously seen. However, high relative humidity resulted in a partial rescue of the exo70A1-1 stigmatic papillar defect resulting is some wild-type compatible pollen acceptance and seed set. Thus, these results reaffirmed Exo70A1’s proposed role in the stigma regulating compatible pollen hydration and pollen tube entry and demonstrate that high relative humidity can partially bypass these functions.


Exo70A1 Compatible pollen acceptance Pollen hydration 



DS was supported by an Ontario Graduate Scholarship (OGS). This research was supported by grants from the Natural Sciences and Engineering Research Council of Canada to MAS and DRG, University start-up grants to MAS, and a Canada Research Chair to DRG.

Supplementary material

497_2014_245_MOESM1_ESM.pdf (154 kb)
Supplementary material 1 (PDF 153 kb)
497_2014_245_MOESM2_ESM.pdf (1.2 mb)
Supplementary material 2 (PDF 1263 kb)


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Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  • Darya Safavian
    • 1
  • Muhammad Jamshed
    • 2
  • Subramanian Sankaranarayanan
    • 2
  • Emily Indriolo
    • 1
  • Marcus A. Samuel
    • 2
  • Daphne R. Goring
    • 1
    • 3
  1. 1.Department of Cell and Systems BiologyUniversity of TorontoTorontoCanada
  2. 2.Department of Biological SciencesUniversity of CalgaryCalgaryCanada
  3. 3.Centre for the Analysis of Genome Evolution and FunctionUniversity of TorontoTorontoCanada

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