Root partial contact with localized organic matter increased 59Fe uptake and alleviated lime-induced chlorosis of young apple trees

Correction of lime-induced chlorosis (LIC) was examined in potted apple (Malus pamila Mill) trees. Manure, as a lime-free organic matter, was added to a calcareous soil by two methods. In the first method, about 1.4 percent of soil was substituted with manure in an auger hole near the tree (localized-placement treatment). Also radioactive iron (59Fe) was added to the hole as a tracer. In the second method, the same amount of manure and 59Fe, were added to the surface soil (surface mixed treatment). The effects of these two methods on some plant parameters were compared with the control treatment which received only 59Fe on the soil surface. Localized-placement, significantly increased root surface area and dry weight near the holes, leaf length, leaf chlorophyll content, leaf iron specific activity (59Fe),and maximum potential efficiency of photosystem II (PS II) of dark adapted leaves, but decreased leaf Fe content. Therefore, results suggests that apple LIC could be corrected by improving localized root growth and development, without using iron fertiliser.