Weak static magnetic fields increase the speed of circumnutation in cucumber (Cucumis sativus L.) tendrils

Abstract

Abstract. Tendrils are thread-like organs whose function is to support the stems of many species of climbing plants. Tendrils naturally move (circumnutate) in space. Individual tendrils of cucumber (Cucumis sativus L.) 'Poinset' had the vertical component of their mean velocity vector of circumnutation changed when exposed to a range of weak static magnetic fields between 1 and 16 mT. The speed (modulus) of the velocity vector was significantly increased (p = 0.016) in the vicinity of a magnet, but its direction did not show a definite trend with respect to the magnet. Although cucumber tendrils bear static positive charges, they did not behave as charged bodies do in a magnetic field, neither did they show a magnetotropic response. In fact, tendrils showed a nastic response to magnetism. Magnetic fields affected some processes underlying the movement of circumnutation, but no clear interpretation of them can be given presently on the basis of the known effects of magnetism on plants. It is clear that cucumber tendrils, because of some inherent susceptibility to magnetism or their particular size and shape, are very sensitive to relatively low static magnetic field strengths.

Circumnutation of Arabidopsis thaliana inflorescence stems

“…It was demonstrated that circumnutation is influenced by various external stimuli including gravity, temperature, mechanical stress and static magnetic fields (Zachariassen et al 1987, Zachariassen and Johnsson 1988, Ginzo and Décima 1995, AndersonBernadas et al 1997, Schuster and Engelmann 1997, Hatakeda et al 2003, Stolarz et al 2003, however, a clear relationship between irradiance and circumnutation has not been demonstrated. The aim of the present paper was to study the influence of irradiance on the circumnutation using Arabidopsis inflorescence stems A. thaliana (L.) Heynh, ecotype Columbia was used in this study.…”

“…There has been many reports about circumnutation, but how to evaluate circumnutating plant organs is not strictly defined. Some of the investigators used the organ's tip loci as index (Ginzo and Décima 1995, Anderson-Bernadas et al 1997, Shabala and Newman 1997, Hatakeda et al 2003, Stolarz et al 2003, some measured periods of one circumnutation (Spurný 1975, Caré et al 1998) and some measured curvature changes (Zachariassen and Johnsson 1988) for analyzing circumnutating organ. In the present study, we measured the curvature development and the nutation frequency as indices of circumnutating inflorescence stems.…”

Alternating magnetic field effects on yield and plant nutrient element composition of strawberry (Fragaria x ananassa cv. camarosa)

“…Tarakanova (1969) reported undesired effects of a high intensity MF. Although several studies have been conducted on effects of static MF on plants (Danilov et al, 1994;Ginzo & Decima, 1995;Samy, 1998;Yano et al, 2001), the effects of alternating MF has not been well documented. Also, the effects of alternating MF on the yield and plant nutrient element composition of leaves of strawberry are not well known.…”

Circumnutations: results from recent experiments on Earth and in space

“…(x) An interesting observation that needs to be quanti®ed and biophysically studied is the change of circumnutation speed of cucumber hypocotyls in the presence of a static magnetic ®eld of a magnitude of about 1 to 15 mT (Ginzo and De cima 1995). This ®eld strength is, of course, higher than that of the Earth's magnetic ®eld, typically of the order of 50 lT.…”