Effects of Salinity Levels on Visual Symptoms of Agroforestry Tree Species

Abstract

Tolerance of eight agroforestry tree species (Acacia nilotica Linn. willd, Azadirachta indica A. Juss, Dalbergia sissoo Roxb, Dalbergia latifolia Roxb., Gmelina arborea Linn., Leucaena leucocephala (Lam)de Wit., Prasopis cineraria Druce and Prosopis iuliflore DC.) to soil salinity was evaluated under pot culture conditions on clayey soil. Four different salt levels viz., 0, 2.5, 3.5 and 6.5 ds/m were created by employing NaCI, CaCI₂ and MgSo₄ in the ratio of 5:3:2. An examination of visual symptoms on the seedlings grown in S2 salinity level (3.5 ds/m) indicated that Dalbergia sissoo Roxb, Dalbergia latifolia Roxb. showed leaf chlorosis along with stunted root growth and in Gmelina arborea linn., severe leaf necrosis along with stunted root growth was observed. In S3 salinity level (6.5 ds/m) complete destruction of shoot and root system occurred in Dalbergia sissoo Roxb, Dalbergia latifolia Roxb. and Gmelina arborea linn., while other tree species namely A. nilotica, A. indica, L. leucocephala, P cineraria and P juliflora showed normal growth with slight reduction in number of leaves, shoot and root length.