Abstract

                                Rotry (1946) as quoted by McKelvy et al (1953) declared rightly that phosphorus is the bottleneck of world's hunger. Acid soils as those found in the Nilgiris pose an economic problem, due to the undesirable nature of the transformation phosphorous undergoes in acid soils. The applied phosphorus is rapidly fixed as insoluble and unavailable compounds. The native reserve of phosphorus also remains unavailable due to the acid conditions which prevent the sesquioxidic phosphates from being released as phosphorus in available forms, as is possible in a limed soil. The magnitude of this problem of phosphorus unavailability can be seen from the abnormal rate of 214 lb of P₂O, in the Nanjanad mixture used extensively on the Nilgiris, though a normal potato crop removes on an average 40 lb P₂O, per acre. Detailed information regarding the phosphorus fixation problem in Nilgiris is not available. Therefore, a detailed study of the tract is indispensable to supply information on this aspect.

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