Analysis Of Wetted Soil For Determination Optimal Irrigation Duration, Discharge Rate And Design Of Drippers Around The Trunk Under 'Tommy Atkins' Mango In Zabid Valley, Tihamah – Yemen

Abstract

Mango is a major fruit crop in Tihamah plain, the most irrigation practices are basin irrigating with low efficiency, 1% only of croups area used modern methods (bubbler, and drib irrigation). Effective of drip irrigation depend several vectors such as determination of crop requirement water, duration irrigation, dripper discharge and system  of distribution of drippers around the trunk, wetted volume at the  root zone. This work aims to determination the best of irrigation duration, discharge rate and distribution of drippers around the trunk under 'Tommy Atkins' mango. The experiment was carried out during October 2016 in a farm, heigh above sea level 127m, located at zabid valley in the southern part of Tihama plain in the west of Yemen. properties of climatical and physical of soil were studies and salinity of water irrigation, three treatments were done, 2d, 4d- 20 cm and 4d- 40 cm, water applied was 80 l for tree treatment and for discharge were used 8, 16 and 32 lph for each treatment, tree irrigation duration were evaluated with each discharge 10 h for 8lph , 5h for 16 lph , 2.5 h for 32 lph. ETC/ day was estimated, hydraulic and physic properties of soil were studded.  Several parameters were evaluated, volume water content, coefficient of uniformity, wetted volume of effective root area and percentage wetted. Results shows, the treatment of 4d- 40 cm with discharge 8 plh and irrigation duration 10h was the best treatment which percentage wetted reached to 100%, witch wetted volume of effective root zone recorded 6m3, average water content reached 26% and coefficient of uniformity are reached to 87%.  also the discharge of 16 lph with duration irrigation 5h can be used for drip irrigation to mango tree, percentage wetted reached 83%. Saved water reached to 68% compared traditional irrigation. Iso- volumetric water content line in the soil profile was done.