Cental Soil Salinity Research Institute, Karnal-132 001.
Comparison of sodium content and 8 other elements (K, Ca, Mg, P, Zn, Cu, Mn and Fe) and associated schorching symptoms in the leaves have been examined in various 1977–78 plantations of mango, guava and ber at different locations. EC of irrigation water being used at these sites varied from 424 to 1986 micromhos/cm and adjusted SAR from 1.8 to 22.5, However at a given site same quality of irrigation water is being used for the three species. In another set of orchards, soils varied from normal (SAR 0.5) to sodic (SAR 23) whereas irrigations waters were normal. Mango accumulated 2\ to 3 times more Na as compared to guava and ber both in old as well as young leaves. Leaf schorching was common in mango, rare in guava and practically absent in ber. Use of sodic water (adjusted SAR 22.5) increased Na content in the foliage of mango 3 to 5| folds over the use of normal waters (adjusted SAR 1.8). However similar increase of Na contents in the leaves of guava and ber did not occur whether soil was sodic or sodic waters are being used for irrigation. Age of the leaf is an important factor determining Na, K, Ca, P, Mn and Fe contents. Use of sodic water did not make the soil sodic possibly because of high leaching during rainy season. Even then leaf schorching was common at these sites. Schorched leaves were found to have high Na concentrations which may be attributed to its uptake along with water fluxes as mass flow. Hence leaf analysis should be used as a diagnostic criteria of specific ion toxicity.
