ABSTRACT
The main objective of this work is to study the effect of sulphur application and irrigation water quantity on some soil properties of the calcareous soils and to limit the suitable concentration to obtain satisfactory yield of faba beab under saline conditions. The study area (Tamyia district, Fayoum Governorate, Egypt) is characterized by a hot and dry climate in general with annual rainfall average of 8 mm/year, whereas the evaporation rates average ranging between 3.5 to10 mm/day. Faba bean (Vicia faba L.) was sown at 18 November 2010 and harvested at 26 April 2011. Total water consumed during faba bean growing season were 623.7 and747.2 m3/ fed for 100% and 120% irrigation treatments with increasing ranged between 3.5% and 3.7% in same sequence. Results showed that values of soil EC, pH and CaCO3 was improved as a result of both irrigation and S treatments. The improvement resulted in a gradual reduction of the studied soil properties by about 10.3%, 3.2%; 17.0% and 23.1%, 4.3%; 11.3% comparing S treated plot relative to the control plot at 100 and 120% irrigation treatments. Application S improved water content under studied soil constant and these increases were 8.8%, 11.8%, 8.3% and 16.9% for SP, FC, WP and AW, respectively relative to the control plots. Irrigation 100% had a positive effect on the drainable pores% which increased by about 7.0% comparing with 120% irrigation treatments. While hydraulic conductivity increased by about 16.4% and percentage of increase drainable pores was 14.0% and 21.4% for 100% and 120% irrigation treatments comparing 3rd layer with the 1st one, respectively. Increasing irrigation water from 100% to 120% resulted increasing in the studied macronutrients, N, P and K, by about 80.8%, 144.9% and 72.9%, respectively; while they increased in plant by about 118.8%, 132.8% and 62.2% as compared with the control one, respectively as a result of S application. Results showed that Na, Cl and Na/K ratio that increasing irrigation water caused increase by 2.02%, 11.11% for Na and Cl, while reduction in the ratio between Na and K was observed with value –15.7% as compared 120 with 100% irrigation treatments. S application cause slightly increases in Na content (3.55%) and moderately increases with Cl (34.38%), which led to decrease Na:K ratio by about 39.4%. Increasing irrigation water by 20%resulted in a gradual increase of both yield and water use efficiency (WUE) of faba bean plants compared with the control plants. Irrigation treatments significantly decreased the contents of proline in dry weight seed of faba bean gradually as a result of increase irrigation quantity (from 100% to 120%) and the reduction was 9.7%. While S addition decreased proline by about 15.9%. According to the interaction effect between irrigation and S application treatments, S improved proline content by about 20.4% and 11.2% relative to the control treatments under 100% and 120% irrigation treatments, respectively %.