FIELD TRIAL OF AZADIRACHTA INDICA (L.) A. JUSS. UNDER HIGHLY SALINE WATER IRRIGATION AT ARID SANDY COASTAL REGION OF PAKISTAN

Abstract

In a field trial at sandy arid coastal land of Bhawani (Gaddani Coast, Baluchistan) Azadirachta indica (L.) A. Just., plants irrigated with highly saline (EC;10.0-15.3 dS.rn-') and sodic (irrigation quality: C.Sz; SAR: c. 28) underground water exhibited relative inhibition of growth in height during winter months. Such inhibition was more conspicuous in stem diameter of the treated plants which was overcome after rainfall (100mm) in April with no difference in height or stem diameter after one year of post-transplantation growth. Saline water irrigation induced no significant change in foliar concentration of moisture, chlorophyll, protein, praline and cations such as Na', IC*, and Mg". Ca" content declined by 41.78% in leaf. Saline irrigation sub¬stantially increased salt content in the upper profile of soil with SAR just on and beyond the critical value, whereas, rainfall (c. 100mm) during April washed down the salts thus reducing the salt content to the same level as tl.at in the virgin soil.