Changes in the composition and content of lipids in the leaves of radish plants of different magnetic orientation induced by weak permanent magnetic field

The effect of weak permanent horizontal magnetic field (PMF) with the intensity of 403 A/m on the composition and content of polar and neutral lipids and their constituent FAs was investigated in the leaves of radish plants (Raphanus sativus L., var. radicula D.C.), cv. Rozovo-krasnyi s belym konchikom, which belong to two major types of magnetic orientation (TMO): North-South (NS) and West-East (WE), with the planes of the root grooves oriented along and across the magnetic meridian, respectively. In spring, PMF reduced the level of total lipids in the NS plants and elevated it in the WE plants; in autumn, the content of total lipids in the NS plants increased in the NS plants and decreased in the WE plants. In spring, the ratio between phospholipids and sterols, which indirectly points to enhanced fluidity of membrane lipid bilayer, increased in the plants of both TMOs, while in autumn, it increased only in the NS plants. In the control plants, the relative content of unsaturated FAs, including linolenic and linoleic acids, was greater in the WE plants than in the NS plants. PMF elevated the content of FAs in the leaves of the NS plants and did not affect their level in the WE plants. It was concluded that weak horizontal PMF differently (and sometimes oppositely) affected the content of lipids in the leaves of the NS and WE radish plants, apparently due to their different sensitivity to the effect of the magnetic field associated with their physiological status.