Impact of Amino Acids and Humic Substances Application on Some Soil Chemical Properties Along with Nutritional Status and Productivity of Wheat Grown under Saline Conditions

Abstract

A field experiment was carried out on saline sandy clay loam soil at Gelbana Village District Sahl-el Tina, North Sinai Governorate, Egypt during two successive winter seasons (2013/2014 and 2014/2015) to study the effect of amino acids (A) , humic substances (H) and amino humate (AH) on soil chemical properties along with nutritional status and productivity of wheat grown under salinity stress condition, using a complete randomized block design with three replicates. The soil was irrigated from El-SalamCanal (a mixture of Nile and agricultural drainage water) .Two rates of amino acids (5Lfed-1) and (10 Lfed-1) along with two rates of humic substances (5Lfed-1) and (10 Lfed-1) as well as two rates of amino humate (5Lfed-1) and(10 Lfed-1) were applied. Results indicated that pH values of the soil after harvesting were slightly decreased as affected by all studied treatments for both tested seasons. Values of EC and ESP were, however, positively affected being with lowest EC values recorded in presence of humic substances (H2) treatment at both tested seasons. Positive response was detected for each of CEC, O.M, nutrient availability in soil after harvesting as well as content of (N,P and K) for straw and grains, the second rate of amino acid (A2) giving the highest values of available N followed by the second rate of amino humate (AH2); as well as the high rate of humic substances (H2) was more responded for increasing P , K availability followed by the second rate of amino humate (AH2). Generally, applied treatments increased significantly soil micronutrients (Fe,Mn,Zn and Cu) availability as compared to control treatment at both studied seasons; increasing the rate of applied amino acids and humic substances caused a significant gradual increase for both studied seasons under investigation. Amino humate (AH2) treatment gave the highest values of (N, P and K) content of grains and straw for wheat at both studied seasons as compared to (AH1) treatment. K/ Na ratio increased gradually by increasing the rate of applied treatments; such positive effect of both tested seasons may be arranged in descending order : amino-humate2> amino acid 2> humic sub. 2 > amino-humate1> amino acid 1> humic sub 1 as compared to control. Increasing the rate each of amino acids and humic substances caused a significant gradual increase in straw and grains of wheat for both studied seasons ; humic sub.( H2 ) was superior as compared with amino acid (A1 ) which was the inferior. The application of humic sub.(H2) recorded a relatively superior in yield percentage components of wheat crop as compared to control. Amino humate 2 was effective on both yield components of straw and grains as compared to ( amino humate1) for both studied season. Protein and proline content s increased significantly in presence of both amino acids and humic substances along with their combination (amino humate ) as compared to control , the high rate of amino acids (A2) being more effective. Leaf total chlorophyll content (A, B and A+B) increased gradually by increasing the rate of applied treatments, high rate of amino acids (A2) being superior as compared to control and other treatments.