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Updated: Mar 14, 2026
12:18
A Strategy to Validate the Role of Callose-mediated Plasmodesmal Gating in the Tropic Response
Published on: April 17, 2016
10.8K
The Cholodny-Went theory does not explain hydrotropism.
Doron Shkolnik1, Hillel Fromm1
1Department of Molecular Biology & Ecology of Plants, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, 69978 Israel.
Summary
Plant roots exhibit hydrotropism, growing towards water. This response does not involve auxin, challenging the Cholodny-Went theory and suggesting inter-cellular signaling mechanisms.
Area of Science:
- Plant biology
- Plant physiology
- Developmental biology
Background:
- Plants optimize water uptake through root growth modulation, a process known as hydrotropism.
- Unlike gravitropism and phototropism, hydrotropism is not explained by auxin redistribution according to the Cholodny-Went theory.
Purpose of the Study:
- To investigate the signaling mechanisms underlying hydrotropism in plant roots.
- To explore alternative pathways to the Cholodny-Went theory for tropic responses.
Main Methods:
- Review of existing literature on plant hydrotropism.
- Discussion of potential signaling molecules and pathways involved in water potential sensing.
Main Results:
- Hydrotropism is independent of the phytohormone auxin.
- Abscisic acid, calcium, and reactive oxygen species are implicated in a dynamic signaling system for hydrotropism.
Conclusions:
- Root hydrotropism relies on inter-cellular signaling pathways.
- The Cholodny-Went theory does not adequately explain the mechanisms of hydrotropism.
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