J. Jpn. Soc. Soil Phys.
No. +*2, p. /+* ,**2¤¥¦§*ῌ¨©ª«¬**ῌ­ª®¯**ῌ°±²³**
Detection of Plant Adaptation Responses to Saline Environment
in Rhizosphere Using Microwave Sensing
Takashi SHIMOMACHI*, Chiaki KOBASHIKAWA**, Hiroaki TANIGAWA** and Emi OMODA*** Faculty of Environmental Studies, Nagasaki University,+ῌ+. Bunkyo-machi, Nagasaki 2/,ῌ2/,+, Japan** Graduate School of Science and Technology, Nagasaki University,+ῌ+. Bunkyo-machi, Nagasaki 2/,ῌ2/,+, JapanAbstract
The physiological adaptation responses in plants to environmental stress, such as water stressand salt stress induce changes in physicochemical conditions of the plant, since formation ofosmotic-regulatory substances can be formed during the environmental adaptation responses.
Strong electrolytes, amino acids, proteins and saccharides are well-known as osmoregulatorysubstances.

Since these substances are ionic conductors and their molecules are electricallydipolar, it can be considered that these substances cause changes in the dielectric properties of theplant, which can be detected by microwave sensing.

The dielectric properties (*.- to - GHz),

water content and water potential of plant leaves which reﬂect the physiological condition of theplant under salt stress were measured and analyzed. Experimental results showed the potentialof the microwave sensing as a method for monitoring adaptation responses in plants under salineenvironment and that suggested the saline environment in rhizosphere can be detected noninvasively and quantitatively by the microwave sensing which detects the changes in complex
dielectric properties of the plant.
Key words : plant, adaptation response, salt stress, complex permittivity, microwave

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dielectric spectrum of vegetation Part + : Ex-trol in Biol., .- : --῏.+.

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