IMPACT OF BUBBLER DISCHARGE AND IRRIGATION WATER QUANTITY ON HYDRAULIC PERFORMANCE EVALUATION AND MAIZE BIOMASS YIELD

Abstract

The aim of current research work is studying the effect of two bubbler irrigation discharges (BD) were: a) 8 LPH and b) 12 LPH, and different water quantity treatments from evapotranspiration (ET): 100%, 75%, 50% on uniformity coefficient (UC%), emission uniformity (EU%) and coefficient of variation (CV%), maize (Zea mays-L., HF-10 Varity) grain and Hay yield. The experiment design is split in randomized complete block with three replicates. So, field experiment for one growing season (2014) was conducted in sandy soil at the Agricultural Research and Production Station of National Research Centre, El- Nubaria, Elbehira Governorate, Egypt. Irrigation water was added in order to compensate for ET of maize. Obtained data could be summarized as follow: Parameters under study could be ranked in following descending orders: 8 LPH>12 LPH and 100>75>50 for bubbler discharge treatments, except for CV%. Investigated bubbler discharge (8 and 12 LPH), increase operating pressure head, getting improvement in UC%, EU% and decreasing CV values. With respect to BD and ET% effect on UC, EU%, maize hay yield, and significant difference at the 1 % level between all mean values of bubblers and ET% treatments were obtained. The interaction effects of the investigated factors, the highest and lowest values of maize hay yield were recorded under 8 LPH X 100% and 12 LPH X 50% ET treatments. These attained results were attributed to the improvement in hydraulic parameters of UC%, EU% and CV Also the Irrigation treatments of 100 and 75% from ET were covered water requirements and also recorded convergent results in values which means that the quantity of water added (which is the difference between the 100-75% =25% ET). It's amount, in excess of the plant required under the current conditions of the experiment. So it can be recommended to using 75% for saving 25% from water requirements under bubbler irrigation system using 8 LPH bubbler.