Effect of Mulching and Drip Irrigation on Water Use Efficiency and Vegetative Growth of Mango under Small Tree System

Abstract

Mango orchards in Pakistan are mostly irrigated using the basin flood method. A considerable quantity of water is lost from basins and channels through evaporation and seepage. During 2020-21, a study was conducted at Mango Small tree system located in MNS University of Agriculture Multan to examine the effect of drip irrigation systems flow rate and mulching in a split-plot design with two treatments and four replications. Main plot treatments consisted of four drip irrigation systems: Loop, single line drippers, bubbler and double line drippers. Moreover, subplots comprised two levels of mulching: no mulch and organic mulch (hay grass). The plants were irrigated by Drip irrigation on daily basis through Loop drippers of two liters per hour liter per hour (lph), single online line drippers of four lph, bubbler of two hundred lph and double online drippers of four lph discharge capacity from November to March. The drip system at a flow rate of four lph and treated with organic mulch recorded the maximum water use efficiency (6.46 kgha-1mm-1), stomatal conductance (140, 25 mmol-1m-2s-1), sub stomatal conductance (65 mmol-1m-2s-1), leaf photosynthetic rate (6.11 mmol-1m-2s-1) and leaf transpiration rate (1.84 mgm-2s-1). The plant height and scion girth did not show significant differences with changes in water flow rate and organic mulches. The maximum soil temperature (38○ C) was recorded in the non-mulched plot. The application of organic mulches not only enhanced the water use efficiency (WUE) and transpiration rate but also improved chlorophyll contents and the number of flushes.